# kb

id: anil-potti-20260505-2
file: data/en.wikipedia.org/wiki/Anil_Potti-2.md
category: reference
title: Anil Potti
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Anil_Potti
date_saved: 2026-05-05T09:30:55.346672+00:00
instance: kb-cron
parent: anil-potti-20260505-0
summary:
"A Genomic Approach to Colon Cancer Risk Stratification Yields Biologic Insights into Therapeutic Opportunities" This article was published by PNAS. Gene expressions could allow the researchers to see if tumours are uniform throughout. This could also be used with Colon Cancer. They also can help predict how a person will respond to treatment and improve prognosis. The authors said they wanted to retract this article because "…we have been unable to reproduce certain key experiments described in the paper regarding validation and use of the colon cancer prognostic signature. This includes the validation performed with dataset E-MEXP-1224, as reported in Fig. 2A, as well as the generation of prognostic scores for colon cancer cell lines, as reported in Fig. 4…" "Validation of Gene Signatures that Predict the Response of Breast Cancer to Neoadjuvant Chemotherapy" This article was published in Lancet Oncology. This study involved patients with oestrogen-receptor-negative breast cancer. The researchers wanted to confirm their previous studies of gene-expression signatures in predicting the effects of chemotherapeutic drugs. The article was retracted because the validity of the results was beginning to be questioned and because predictions were made off of the Nature Medicine article that was retracted. "Genomic Signatures to Guide


id: project-alpha-hoax-20260505-0
file: data/en.wikipedia.org/wiki/Project_Alpha_(hoax)-0.md
category: reference
title: Project Alpha (hoax)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Project_Alpha_(hoax)
date_saved: 2026-05-05T09:30:56.533475+00:00
instance: kb-cron
parent: project-alpha-hoax-20260505-0
summary:
Project Alpha was an effort by magician James Randi to test the quality of scientific rigor of a well-known test of paranormal phenomena. In the late 1970s, Randi contacted the newly established McDonnell Laboratory for Psychical Research ("MacLab") with suggestions on how to conduct tests for paranormal phenomena. At the same time, two teenage boys (Steve Shaw, later known as Banachek, and Mike Edwards) independently contacted the McDonnell Laboratory and volunteered as subjects for such tests from 1979 to 1982. They quickly proved to exhibit a range of paranormal abilities far and away better than the other subjects of the experiment. The lab began leaking reports of the pair's capabilities, which were in fact simple magic tricks. When rumors of the test subjects' connection to Randi reached Peter Phillips, head of the MacLab, he instituted tighter protocols for the experiments; the two subjects' results declined sharply. In 1983, Randi held a press conference to expose the deception in the wake of Project Alpha, as there were a number of controversies about the ethics of interference in scientific research and the validity of paranormal research as it then existed. It remains a watershed event in the field of parapsychology. == McDonnell


id: project-alpha-hoax-20260505-1
file: data/en.wikipedia.org/wiki/Project_Alpha_(hoax)-1.md
category: reference
title: Project Alpha (hoax)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Project_Alpha_(hoax)
date_saved: 2026-05-05T09:30:56.533475+00:00
instance: kb-cron
parent: project-alpha-hoax-20260505-0
summary:
== Steven Shaw and Michael Edwards == When the establishment of the laboratory was announced, Mike Edwards, 18, and Steven Shaw, 17, now known as Banachek, both magicians, each contacted Randi independently with a plan. They proposed to use their skills to deceive the researchers with tricks during the first stages of the investigations. They were chosen as test subjects and the hoax began. The project had originally started with spoon bending, so the two quickly developed a way to accomplish this. Contrary to one of the caveats Randi noted in his letter, the test setup included not one, but many and various spoons, labeled with paper on a loop of string instead of any sort of permanent marking. When starting to bend a spoon, the two magicians would complain the labels were in the way and remove them. They would then simply switch the labels when putting them back and wait. The spoons were measured before and after the experiment, and since all sorts of spoons were used, simply switching the labels would produce different measurements, causing the scientist to believe that something paranormal had occurred. In other cases, they would drop one of the spoons in their lap


id: project-alpha-hoax-20260505-2
file: data/en.wikipedia.org/wiki/Project_Alpha_(hoax)-2.md
category: reference
title: Project Alpha (hoax)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Project_Alpha_(hoax)
date_saved: 2026-05-05T09:30:56.533475+00:00
instance: kb-cron
parent: project-alpha-hoax-20260505-0
summary:
Phillips decided to release a research brief at a workshop of the Parapsychological Association Convention in August 1981. According to the researchers' official version, in preparation Phillips also wrote to Randi to ask for a tape of fake metal-bending, which was to be shown alongside the recording of Shaw and Edwards. The researchers were looking for critical input from the parapsychology community and afterward released a revised abstract that reflected the received criticism. After the Project Alpha announcements in the press, Randi wrote to the lab again and stated that it was entirely possible the two were magicians using common sleight of hand to fool the researchers. He also started to leak stories that the two were his plants. The story had been widely circulated by the time the meeting was held the next month. Upon returning from the meeting, Phillips immediately changed the test protocols; Shaw and Edwards found that they were no longer able to fool the experimenters so easily, and in most cases, unable to fool them at all. During this time the lab started releasing additional reports that seriously toned down the success rate. In their own words, "We did not conclude that they must be


id: red-mercury-20260505-0
file: data/en.wikipedia.org/wiki/Red_mercury-0.md
category: reference
title: Red mercury
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Red_mercury
date_saved: 2026-05-05T09:30:57.782261+00:00
instance: kb-cron
parent: red-mercury-20260505-0
summary:
Red mercury is a discredited substance, most likely a hoax perpetrated by con artists who sought to take advantage of gullible buyers on the black market for arms. These con artists described it as a substance used in the creation of nuclear weapons; because of the secrecy surrounding nuclear weapons development, it is difficult to disprove their claims completely. However, all samples of alleged "red mercury" analyzed in the public literature have proven to be well-known, common substances of no interest to weapons makers. == History == References to red mercury first appeared in major Soviet and western media sources in the late 1980s. The articles were never specific as to what exactly red mercury was, but nevertheless claimed it was of great importance in nuclear bombs, or that it was used in the building of boosted fission weapons. Almost as soon as the stories appeared, people started attempting to buy it. At that point, the purported nature of the substance started to change, and eventually turned into anything the buyer happened to be interested in. As New Scientist reported in 1992, a Lawrence Livermore National Laboratory report outlined that: When red mercury first appeared on the international black market


id: red-mercury-20260505-1
file: data/en.wikipedia.org/wiki/Red_mercury-1.md
category: reference
title: Red mercury
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Red_mercury
date_saved: 2026-05-05T09:30:57.782261+00:00
instance: kb-cron
parent: red-mercury-20260505-0
summary:
== Analysis == Several common mercury compounds are indeed red, such as mercury sulfide (from which the bright-red pigment vermilion was originally derived), mercury(II) oxide (historically called red precipitate), and mercury(II) iodide. No use for any of these compounds in nuclear weapons has been publicly documented. "Red mercury" could also be a code name for a substance that contains no mercury at all. A variety of different items have been chemically analyzed as putative samples of "red mercury" since the substance first came to the attention of the media, but no single substance was found in these items. A sample of radioactive material was seized by German police in May 1994. This consisted of a complex mixture of elements, including about 10% by weight plutonium, with the remainder consisting of 61% mercury, 11% antimony, 6% oxygen, 2% iodine and 1.6% gallium. The reason why somebody had assembled this complex mixture of chemicals is unknown; equally puzzling was the presence of fragments of glass and brush bristles, suggesting that someone had dropped a bottle of this substance and then swept it up into a new container. In contrast, an analysis reported in 1998 of a different "red mercury" sample concluded that


id: red-mercury-20260505-2
file: data/en.wikipedia.org/wiki/Red_mercury-2.md
category: reference
title: Red mercury
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Red_mercury
date_saved: 2026-05-05T09:30:57.782261+00:00
instance: kb-cron
parent: red-mercury-20260505-0
summary:
=== Red mercury as a ballotechnic === Samuel T. Cohen, the "father of the neutron bomb", claimed for a long time that red mercury is a powerful explosive-like chemical known as a ballotechnic. The energy released during its reaction is allegedly enough to directly compress the secondary without the need for a fission primary in a thermonuclear weapon. He claimed that he learned that the Soviet scientists perfected the use of red mercury and used it to produce a number of softball-sized pure fusion bombs weighing as little as 10 lb (4.5 kg), which he claimed were made in large numbers. He went on to claim that the reason this is not more widely known is that elements within the US power structure are deliberately suppressing or hiding information due to the frightening implications such a weapon would have on nuclear proliferation. Since a red mercury bomb would require no fissile material, it would seemingly be impossible to protect against its widespread proliferation given current arms control methodologies. Instead of trying to do so, they simply claim it does not exist, while acknowledging its existence privately. Cohen also claimed that when President Boris Yeltsin took power, he secretly authorized the


id: red-mercury-20260505-3
file: data/en.wikipedia.org/wiki/Red_mercury-3.md
category: reference
title: Red mercury
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Red_mercury
date_saved: 2026-05-05T09:30:57.782261+00:00
instance: kb-cron
parent: red-mercury-20260505-0
summary:
=== Saudi Arabia === In April 2009 it was reported from Saudi Arabia that rumors that Singer sewing machines contained "red mercury" had caused the prices of such machines to massively increase in the Kingdom, with some paying up to SR200,000 for a single machine which could previously have been bought for SR200. Believers in the rumor claimed that the presence of red mercury in the sewing machines' needles could be detected using a mobile telephone; if the line cut off when the telephone was placed near to the needle, this supposedly proved that the substance was present. In Medina there was a busy trade in the sewing machines, with buyers seen using mobile phones to check the machines for red mercury content, while it was reported that others had resorted to theft, with two tailors' shops in Dhulum broken into and their sewing machines stolen. At other locales, there were rumors that a Kuwait-based multinational had been buying up the Singer machines, while in Al-Jouf, the residents were led to believe that a local museum was buying up any such machines that it could find, and a number of women appeared at the museum offering to sell their Singer


id: charles-redheffer-20260505-0
file: data/en.wikipedia.org/wiki/Charles_Redheffer-0.md
category: reference
title: Charles Redheffer
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Charles_Redheffer
date_saved: 2026-05-05T09:30:58.927602+00:00
instance: kb-cron
parent: charles-redheffer-20260505-0
summary:
Charles Redheffer was an American inventor who claimed to have invented a perpetual motion machine. First appearing in Philadelphia, Redheffer exhibited his machine to the public, charging high prices for viewing. When he applied to the government for more money, a group of inspectors were sent to examine the machine. It was discovered the machine was actually powered by a device Redheffer claimed was powered by the machine. Redheffer moved to New York City and set up a similar scam after rebuilding his machine. However, an engineer detected that it was a fake by listening to its unsteady motions at an exhibition. He discovered that the machine was operated by a man using a crank in a room on the floor above. Redheffer returned to Philadelphia. He later claimed to have created another machine, but refused to demonstrate it to anyone. He managed to get a patent for his machine in 1820, but after this his fate is unknown. == Personal life == Little has been recorded about Redheffer's life, other than his connection to the hoax. According to one source, he was from Germantown in Philadelphia, but most sources simply state that he appeared in Philadelphia with his machine.


id: scott-reuben-20260505-0
file: data/en.wikipedia.org/wiki/Scott_Reuben-0.md
category: reference
title: Scott Reuben
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Scott_Reuben
date_saved: 2026-05-05T09:31:00.148714+00:00
instance: kb-cron
parent: scott-reuben-20260505-0
summary:
Scott S. Reuben (born 1958) is an American anesthesiologist who falsified data heralding the benefits of the Pfizer pain medication Celebrex while downplaying its negative side effects. He was Professor of Anesthesiology and Pain Medicine at Tufts University in Boston, Massachusetts and chief of acute pain at Baystate Medical Center in Springfield, Massachusetts from February 1991 until 2009 when he was sentenced to prison for healthcare fraud. Reuben was considered to be a prolific and influential researcher in pain management, and his purported findings altered the way millions of patients are treated for pain during and after orthopedic surgeries. Reuben has now admitted that he never conducted any of the clinical trials on which his conclusions were based "in what may be considered the longest-running and widest-ranging cases of academic fraud." Scientific American has called Reuben the medical equivalent of Bernie Madoff, the former NASDAQ chairman who was convicted of orchestrating a $65-billion Ponzi scheme. == Background == Reuben was educated at Columbia University. He graduated from medical school at the State University of New York at Buffalo in 1985 and undertook his anesthesiology residency at Mount Sinai Medical Center in New York City. Reuben fell under suspicion when Baystate


id: rhinogradentia-20260505-0
file: data/en.wikipedia.org/wiki/Rhinogradentia-0.md
category: reference
title: Rhinogradentia
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Rhinogradentia
date_saved: 2026-05-05T09:31:01.299956+00:00
instance: kb-cron
parent: rhinogradentia-20260505-0
summary:
Rhinogradentia is a fictitious order of extinct shrew-like mammals invented by German zoologist Gerolf Steiner. Members of the order, known as rhinogrades or snouters, are characterized by a nose-like feature called a "nasorium", which evolved to fulfill a wide variety of functions in different species. Steiner also created a fictional persona, naturalist Harald Stümpke, who is credited as author of the 1961 book Bau und Leben der Rhinogradentia (translated into English in 1967 as The Snouters: Form and Life of the Rhinogrades). According to Steiner, it is the only remaining record of the animals, which were wiped out, along with all the world's Rhinogradentia researchers, when the small Pacific archipelago they inhabited sank into the ocean due to nearby atomic bomb testing. Successfully mimicking a genuine scientific work, Rhinogradentia has appeared in several publications without any note of its fictitious nature, sometimes in connection with April Fools' Day. == Background == Rhinogradentia, their island home of Hy-yi-yi, zoologist Harald Stümpke, and a host of other people, places, and documents are fictional creations of Gerolf Steiner (1908–2009), a German zoologist. Steiner is best known for his fictional work as Stümpke, but he was an accomplished zoologist in his own right. He


id: rhinogradentia-20260505-1
file: data/en.wikipedia.org/wiki/Rhinogradentia-1.md
category: reference
title: Rhinogradentia
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Rhinogradentia
date_saved: 2026-05-05T09:31:01.299956+00:00
instance: kb-cron
parent: rhinogradentia-20260505-0
summary:
== Publication history == Steiner's books as Stümpke have been translated into other languages, sometimes crediting other names based on the country of publication. "Harald Stümpke", "Massimo Pandolfi", "Hararuto Shutyunpuke", and "Karl D. S. Geeste" are pseudonyms. Translator names are real. Stümpke, Harald (1957). Bau und Leben der Rhinogradentia. Stuttgart: Gustav Fischer Verlag. ISBN 3-437-30083-0. OCLC 65616734. Stümpke, Harald (1962). Anatomie et Biologie des Rhinogrades — Un Nouvel Ordre de Mammifères (Trans. Robert Weill). Paris: Masson. ISBN 978-2-10-005449-7. OCLC 46829688. Stümpke, Harald (1967). The Snouters: Form and Life of the Rhinogrades (Trans. Leigh Chadwick). Garden City, NY: The Natural History Press. OCLC 436148. Pandolfi, Massimo (1992). I Rinogradi di Harald Stümpke e la zoologia fantastica (Trans. Achaz von Hardenberg). Padua: Franco Muzzio. ISBN 88-7021-485-0. OCLC 875787215. Shutyunpuke, Hararuto (1997). Bikōri: atarashiku-hakken-sareta-honyūrui-no-kōzō-to-seikatsu. Tokyo: Hakuhinsha. ISBN 4-938706-19-9. OCLC 76500640. Geeste, Karl D. S. (1988). Stümpke's Rhinogradentia: Versuch einer Analyse. Stuttgart: Gustav Fischer Verlag. ISBN 3-437-30597-2. OCLC 28345723. == Legacy == Rhinogradentia is considered one of the best known biological hoaxes and scientific jokes and Steiner's pseudonymous works on the subject continue to be reprinted and translated. The first edition did not explicitly state that it was a hoax. Following the publication of


id: sch-n-scandal-20260505-0
file: data/en.wikipedia.org/wiki/Schön_scandal-0.md
category: reference
title: Schön scandal
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Schön_scandal
date_saved: 2026-05-05T09:31:02.514203+00:00
instance: kb-cron
parent: sch-n-scandal-20260505-0
summary:
German physicist Jan Hendrik Schön (born August 1970 in Verden an der Aller, Lower Saxony, West Germany) briefly rose to prominence after a series of apparently successful experiments with semiconductors that were discovered later to be fraudulent. Before he was exposed, Schön had received the Otto-Klung-Weberbank Prize for Physics and the Braunschweig Prize in 2001, as well as the Outstanding Young Investigator Award of the Materials Research Society in 2002, all of which were later rescinded. He was also supposed to receive the William L. McMillan Award from the University of Illinois in 2002, but due to the intervention of Daniel C. Ralph of Cornell University (who was on the committee of the McMillan Award), Schön was never given the award. The scandal provoked discussion in the scientific community about the degree of responsibility which coauthors and reviewers of scientific articles bear in cases of scientific misbehavior. The discussion mainly concerned whether peer review, traditionally designed to find errors and determine relevance and originality of articles, should also be required to detect deliberate fraud. == Beginning of fame == Schön's topic of research was condensed matter physics and nanotechnology. He received his PhD from the University of Konstanz in 1997.


id: sch-n-scandal-20260505-1
file: data/en.wikipedia.org/wiki/Schön_scandal-1.md
category: reference
title: Schön scandal
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Schön_scandal
date_saved: 2026-05-05T09:31:02.514203+00:00
instance: kb-cron
parent: sch-n-scandal-20260505-0
summary:
== Allegations and investigation == Soon after Schön published his work on single-molecule semiconductors, others in the physics community alleged that his data contained anomalies. Julia Hsu and Lynn Loo originally noticed problems with Schön's paper describing the assembly of molecular transistors while attempting to patent research concerning lithography, realizing that Schön had duplicated some numbers. Hsu and Loo had attempted initial experiments to gather evidence for their patent but relied on the scientific outcomes of Schön's work. It was not until April 19, 2002, when Loo and Hsu were meeting with their patent lawyer John McCabe, that they noticed the duplicated data. Hsu and Loo both contacted Robert Willett, who then contacted one of his old postdoctoral students, Lydia Sohn, telling her to look out for a correction in one of Schön's papers. Sohn, then of Princeton University, noticed that two experiments carried out at very different temperatures had identical noise. When the editors of Nature mentioned this to Schön, he claimed to have accidentally submitted the same graph twice. Paul McEuen of Cornell University then found the same noise in a paper describing a third experiment. More research by McEuen, Sohn, Loo, and other physicists revealed a number


id: sch-n-scandal-20260505-2
file: data/en.wikipedia.org/wiki/Schön_scandal-2.md
category: reference
title: Schön scandal
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Schön_scandal
date_saved: 2026-05-05T09:31:02.514203+00:00
instance: kb-cron
parent: sch-n-scandal-20260505-0
summary:
J. H. Schön; S. Berg; Ch. Kloc; B. Batlogg (2000). "Ambipolar Pentacene Field-Effect Transistors and Inverters". Science. 287 (5455): 1022–3. Bibcode:2000Sci...287.1022S. doi:10.1126/science.287.5455.1022. PMID 10669410. (Retracted, see doi:10.1126/science.298.5595.961b, PMID 12416506) J. H. Schön; Ch. Kloc; R. C. Haddon; B. Batlogg (2000). "A Superconducting Field-Effect Switch". Science. 288 (5466): 656–8. doi:10.1126/science.288.5466.656. PMID 10784445. S2CID 37783357. (Retracted, see doi:10.1126/science.298.5595.961b, PMID 12416506) J. H. Schön; Ch. Kloc; B. Batlogg (2000). "Fractional Quantum Hall Effect in Organic Molecular Semiconductors". Science. 288 (5475): 2338–40. doi:10.1126/science.288.5475.2338. PMID 17769842. (Retracted, see doi:10.1126/science.298.5595.961b, PMID 12416506) J. H. Schön; Ch. Kloc; A. Dodabalapur; B. Batlogg (2000). "An Organic Solid State Injection Laser". Science. 289 (5479): 599–601. Bibcode:2000Sci...289..599S. doi:10.1126/science.289.5479.599. PMID 10915617. (Retracted, see doi:10.1126/science.298.5595.961b, PMID 12416506) J. H. Schön; Ch. Kloc; B. Batlogg (2000). "A Light-Emitting Field-Effect Transistor". Science. 290 (5493): 963–6. Bibcode:2000Sci...290..963S. doi:10.1126/science.290.5493.963. PMID 11062124. (Retracted, see doi:10.1126/science.298.5595.961b, PMID 12416506) J. H. Schön; Ch. Kloc; H. Y. Hwang; B. Batlogg (2001). "Josephson Junctions with Tunable Weak Links". Science. 292 (5515): 252–4. doi:10.1126/science.1058812. PMID 11303093. S2CID 38719808. (Retracted, see doi:10.1126/science.298.5595.961b, PMID 12416506) J. H. Schön; A. Dodabalapur; Ch. Kloc; B. Batlogg (2001). "High-Temperature Superconductivity in Lattice-Expanded C60". Science. 293 (5539): 2432–4. Bibcode:2001Sci...293.2432S. doi:10.1126/science.1064773. PMID 11533443. S2CID 28759665. (Retracted, see doi:10.1126/science.298.5595.961b, PMID


id: sch-n-scandal-20260505-3
file: data/en.wikipedia.org/wiki/Schön_scandal-3.md
category: reference
title: Schön scandal
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Schön_scandal
date_saved: 2026-05-05T09:31:02.514203+00:00
instance: kb-cron
parent: sch-n-scandal-20260505-0
summary:
J. H. Schön; Z. Bao (2002). "Organic insulator/semiconductor heterostructure monolayer transistors". Applied Physics Letters. 80 (2): 332. Bibcode:2002ApPhL..80..332S. doi:10.1063/1.1431697. S2CID 95860889. J. H. Schön; Ch. Kloc; A. Dodabalapur; B. Crone (2001). "Grain boundary transport and vapor sensing in α-sexithiophene". Applied Physics Letters. 79 (24): 3965. Bibcode:2001ApPhL..79.3965S. doi:10.1063/1.1423787. J. H. Schön; C. Kloc (2001). "Charge transport through a single tetracene grain boundary". Applied Physics Letters. 78 (24): 3821. Bibcode:2001ApPhL..78.3821S. doi:10.1063/1.1379986. J. H. Schön; C. Kloc (2001). "Organic metal–semiconductor field-effect phototransistors". Applied Physics Letters. 78 (22): 3538. Bibcode:2001ApPhL..78.3538S. doi:10.1063/1.1376666. J. H. Schön; C. Kloc; B. Batlogg (2000). "Efficient photovoltaic energy conversion in pentacene-based heterojunctions". Applied Physics Letters. 77 (16): 2473. Bibcode:2000ApPhL..77.2473S. doi:10.1063/1.1318234. J. H. Schön; C. Kloc; B. Batlogg (1999). "Reversible gas doping of bulk α-hexathiophene". Applied Physics Letters. 75 (11): 1556. Bibcode:1999ApPhL..75.1556S. doi:10.1063/1.124753. J. H. Schön; Ch. Kloc; R. A. Laudise; B. Batlogg (1998). "Surface and bulk mobilities of oligothiophene single crystals". Applied Physics Letters. 73 (24): 3574. Bibcode:1998ApPhL..73.3574S. doi:10.1063/1.122828. The retraction notice from March 20, 2003, in Advanced Materials mentions concerns about another article written by Schön: J. H. Schön; C. Kloc; Z. Bao; B. Batlogg (2000). "Electron Transport in Fluorinated Copper-Phthalocyanine". Advanced Materials. 12 (20): 1539–1542. doi:10.1002/1521-4095(200010)12:20<1539::AID-ADMA1539>3.0.CO;2-S. == See


id: scigen-20260505-0
file: data/en.wikipedia.org/wiki/SCIgen-0.md
category: reference
title: SCIgen
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/SCIgen
date_saved: 2026-05-05T09:31:03.709962+00:00
instance: kb-cron
parent: scigen-20260505-0
summary:
SCIgen is a paper generator that uses context-free grammar to randomly generate nonsense in the form of computer science research papers. Its original data source was a collection of computer science papers downloaded from CiteSeer. All elements of the papers are formed, including graphs, diagrams, and citations. Created by scientists at the Massachusetts Institute of Technology, its stated aim is "to maximize amusement, rather than coherence." Originally created in 2005 to expose the lack of scrutiny of submissions to conferences, the generator subsequently became used, primarily by Chinese academics, to create large numbers of fraudulent conference submissions, leading to the retraction of 122 SCIgen generated papers and the creation of detection software to combat its use. == Sample output == Opening abstract of Rooter: A Methodology for the Typical Unification of Access Points and Redundancy: Many physicists would agree that, had it not been for congestion control, the evaluation of web browsers might never have occurred. In fact, few hackers worldwide would disagree with the essential unification of voice-over-IP and public/private key pair. In order to solve this riddle, we confirm that SMPs can be made stochastic, cacheable, and interposable. == Prominent results == In 2005, a paper generated by


id: scigen-20260505-1
file: data/en.wikipedia.org/wiki/SCIgen-1.md
category: reference
title: SCIgen
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/SCIgen
date_saved: 2026-05-05T09:31:03.709962+00:00
instance: kb-cron
parent: scigen-20260505-0
summary:
==== In journals ==== Students at Iran's Sharif University of Technology published a paper in Elsevier's Journal of Applied Mathematics and Computation. The students wrote under the surname "MosallahNejad", which translates literally from Persian language (in spite of not being a traditional Persian name) as "from an Armed Breed". The paper was subsequently removed when the publishers were informed that it was a joke paper. Mikhail Gelfand published a translation of the "Rooter" article in the Russian-language Journal of Scientific Publications of Aspirants and Doctorants in August 2008. Gelfand was protesting against the journal, which was apparently not peer-reviewed and was being used by Russian PhD candidates to publish in an "accredited" scientific journal, charging them 4,000 Rubles to do so. The accreditation was revoked two weeks later. (See Dissernet for related information.) Springer Science+Business Media and IEEE were also the subject of similar pranks. === Spoofing Google Scholar and h-index calculators === Refereeing performed on behalf of the Institute of Electrical and Electronics Engineers has also been subject to criticism after fake papers were discovered in conference publications, most notably by Labbé and a researcher using the pseudonym of Schlangemann. Cyril Labbé from Grenoble University demonstrated the vulnerability of


id: skvader-20260505-0
file: data/en.wikipedia.org/wiki/Skvader-0.md
category: reference
title: Skvader
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Skvader
date_saved: 2026-05-05T09:31:04.854490+00:00
instance: kb-cron
parent: skvader-20260505-0
summary:
The skvader (pronounced [ˈskvɑ̌ːdɛr]) is a Swedish fictional creature that was constructed in 1918 by the taxidermist Rudolf Granberg and is permanently displayed at the museum at Norra Berget in Sundsvall. It has the head, forequarters and hindlegs of a European hare (Lepus europaeus), and the back, wings and tail of a female wood grouse (Tetrao urogallus). It was later jokingly given the Latin name Tetrao lepus pseudo-hybridus rarissimus L. The term has taken on a general meaning of two disparate elements put together, often conveying a sense of a less fortunate such combination. == Name == The name is a combination of two words, explained by the Svenska Akademiens ordbok (Dictionary of the Swedish Academy) as being from the "prefix skva- from skvattra (quack or chirp), and the suffix -der from tjäder (wood grouse)". == Origins == The skvader originates from a tall tale hunting story told by a man named Håkan Dahlmark during a dinner at a restaurant in Sundsvall in the beginning of the 20th century. To the amusement of the other guests, Dahlmark claimed that he in 1874 had shot such an animal during a hunt north of Sundsvall. On his birthday in 1907, his housekeeper


id: andriy-slyusarchuk-20260505-0
file: data/en.wikipedia.org/wiki/Andriy_Slyusarchuk-0.md
category: reference
title: Andriy Slyusarchuk
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Andriy_Slyusarchuk
date_saved: 2026-05-05T09:31:06.020817+00:00
instance: kb-cron
parent: andriy-slyusarchuk-20260505-0
summary:
Andriy Tykhonovych Slyusarchuk (Ukrainian: Андрі́й Ти́хонович Слюсарчу́к, born 10 May 1971) is a Ukrainian mnemonist who has claimed to be a general aviation pilot, psychotherapist, Doctor of Science in medicine, psychiatrist, psychologist and neurosurgeon. He has performed brain surgery throughout Ukraine in state and municipal hospitals. Slyusarchuk has been employed by the V. Chornovol Lviv State Institute of Modern Technology and Management, the Kyiv National University of Construction and Architecture, the P.L. Shupyk National Medical Academy of Postgraduate Education, and the A. P. Romodanov Institute of Neurosurgery. He has lectured at the Lviv Polytechnic, and worked for the government of Ukraine as an adviser to Oleksandr Turchynov. Slyusarchuk claimed to have set several world records in mnemonics by memorizing data and figures (such as pi) and performing complex calculations in his mind. Because of this, he came to be known as "Doctor Pi". Slyusarchuk defrauded two Ukrainian presidents: Viktor Yushchenko and Viktor Yanukovych. The Verkhovna Rada (the Ukrainian Parliament) referred to his activities as "the largest-scale fraud in Ukraine's 20 years of independence". On 14 February 2014, the Sykhiv Raion Court sentenced Slyusarchuk to eight years in prison. == Education and career == Slyusarchuk's education began in an institutional school


id: andriy-slyusarchuk-20260505-1
file: data/en.wikipedia.org/wiki/Andriy_Slyusarchuk-1.md
category: reference
title: Andriy Slyusarchuk
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Andriy_Slyusarchuk
date_saved: 2026-05-05T09:31:06.020817+00:00
instance: kb-cron
parent: andriy-slyusarchuk-20260505-0
summary:
== Biography == The details of Andriy Slyusarchuk's life were uncovered through investigative journalism. Slyusarchuk was born in Zhytomyr, Ukraine on 10 May 1971. His 21-year-old mother, Natalia Tykhonovna Slyusarchuk of Zhytomyr, left her newborn son at a maternity home. She did not know the name of the father of her child, and Slyusarchuk's middle name was recorded on his birth certificate as "Tykhonovych" (the masculine version of Natalia Slyusarchuk's patronymic). He was hospitalized at the Zhytomyr psychiatric hospital eight times between 1974 and 1987. From 1980 to 1987 (second to eighth grade) Slyusarchuk lived and studied at an institutional school for young orphans in the town of Hryshkivtsi in Berdychiv Raion, receiving a certificate for the completion of his education there. Nearly all the documents pertaining to his education at the school were later destroyed; his birth date became 19 May 1974 on some documents, yielding negative results for official inquiries about his time at the school. From 1987 to 1989, Slyusarchuk studied in the 208th group at the inter-regional Higher Vocational School of Railway Transport in Kozyatyn, Vinnytsia Oblast, to become a plasterer-tiler-facing worker. On 2 October 1989, according to order No. 31, he was transferred to the


id: andriy-slyusarchuk-20260505-2
file: data/en.wikipedia.org/wiki/Andriy_Slyusarchuk-2.md
category: reference
title: Andriy Slyusarchuk
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Andriy_Slyusarchuk
date_saved: 2026-05-05T09:31:06.020817+00:00
instance: kb-cron
parent: andriy-slyusarchuk-20260505-0
summary:
It was followed by "The First Victims of Pseudo-professor Pi", "Pseudo-doctor Slyusarchuk Kills People", "The Cheap Tricks of Professor Pi", "The New Victims of the Pseudo-Doctor", "Pseudo-doctor Slyusarchuk is in a Trap", "Pseudo-doctor Slyusarchuk Buried His Mother Alive", "The Pseudo-Doctor Sows New Deaths", "It is Just a Shock. The Pseudo-doctor Kills the Child of a Priest", "The Pi Record is Cancelled", "The Pi Record is Falsified," "The Secret Protectors of Doctor Pi", "The Pseudo-Doctor Again Picked Up a Scalpel", "The Perverts of Minister Tabachnyk", "The Pseudo-Doctor, Sex and Drugs", "The Grave Sin of Minister Tabachnyk", "Three More New Victims of the Pseudo-Doctor" (a video), "The New Attitude of Doctor Pi", "The Intelligentsia of the Lviv Oblast Demand that Tabachnyk, Who is an Accessory of Doctor Pi, Be Relieved of His Position", "The Computer Operator of Doctor Pi Speaks Out", "New Actions Brought Against the Pseudo-Doctor", "A New Death in the Case of Doctor Pi", "The Millions of Doctor Pi Against Ekspres", "The Inquest Breaks the Action Brought Against Doctor Pi", "Doctor Pi is Ignorant of Even Arithmetic", "Doctor Pi Took Up to Tens of Thousands". After the Ekspres articles were published, criminal complaints were again brought against Slyusarchuk. On 14


id: andriy-slyusarchuk-20260505-3
file: data/en.wikipedia.org/wiki/Andriy_Slyusarchuk-3.md
category: reference
title: Andriy Slyusarchuk
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Andriy_Slyusarchuk
date_saved: 2026-05-05T09:31:06.020817+00:00
instance: kb-cron
parent: andriy-slyusarchuk-20260505-0
summary:
=== Biography based on Slyusarchuk's own interviews === According to a birth certificate shown by him to journalists, Slyusarchuk was born in the village of Tuğ in the Hadrut Rayon of the Nagorno-Karabakh Autonomous Oblast of the Azerbaijan Soviet Socialist Republic. His father was Mushegyan Vartan Aramovich, an ethnic Armenian. His mother, a Ukrainian, was Ruslana Tykhonovna Slyusarchuk. The Hadrut Rayon civil registry reportedly changed his birth details to his mother's by request in 1984, and he became Andriy Tykhonovych Slyusarchuk. Slyusarchuk said that he graduated from a secondary school in Vinnytsia at the age of nine. His parents, medical professionals (his mother a pediatrician and his father a cardiac surgeon), died in a car accident the year he graduated from secondary school. During the 1980s he was subjected to punitive psychiatry, physically abused and sent to a psychiatric hospital where he was tied to a bed, given psychoactive drugs and injected with sulfozin. When the psychiatrists asked him which books he was reading, Slyusarchuk said that he was reading medical literature and works by Ivan Pavlov and Vladimir Lenin. He was sent to an institution for the mentally-ill children. Slyusarchuk was placed in a Soviet orphanage where he was


id: andriy-slyusarchuk-20260505-4
file: data/en.wikipedia.org/wiki/Andriy_Slyusarchuk-4.md
category: reference
title: Andriy Slyusarchuk
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Andriy_Slyusarchuk
date_saved: 2026-05-05T09:31:06.020817+00:00
instance: kb-cron
parent: andriy-slyusarchuk-20260505-0
summary:
== Mnemonics and hypnosis == Slyusarchuk claimed to have set records for memorizing large amounts of digital data, sequences of geometric figures, words and other information, including one million digits of the figure pi. By 2008, he claimed to have memorized two million decimal places of pi and about 7,000 volumes of text; by the following year, his claim had increased to 15,000 volumes. By June 2009 Slyusarchuk claimed to have set a record by memorizing the first 30 million decimal places of pi, which were printed in 20 volumes of text. He claimed to have memorized 200 million decimal places of pi by October 2010. None of the claimed pi records appear on the Pi World Ranking list. Slyusarchuk was known for his hypnotic skill; he claimed the ability to hypnotize people to feel no pain when burned. On a TV show, he hypnotized students of the L'viv University of Modern Technology (Львівський державний інститут новітніх технологій та управління ім. В. Чорновола) into believing that the onions they ate were apples. Slyusarchuk demonstrated hypnosis of a salesman who accepted a ₴1 bill, thinking it was a ₴500 bill. His televised demonstration of chess-position memory (memorizing all pieces on 80


id: andriy-slyusarchuk-20260505-5
file: data/en.wikipedia.org/wiki/Andriy_Slyusarchuk-5.md
category: reference
title: Andriy Slyusarchuk
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Andriy_Slyusarchuk
date_saved: 2026-05-05T09:31:06.020817+00:00
instance: kb-cron
parent: andriy-slyusarchuk-20260505-0
summary:
On 6 October 2011 the Lviv newspaper Ekspres published its first article critical of Slyusarchuk, "The Sensational Exposure of Pseudo-Professor Pi", accusing him of forgery and fraud and investigating him in subsequent articles. Three weeks later, the newspaper published a letter from the Russian National Research Medical University saying that Slyusarchuk had not studied at the university. On 10 January 2012 the newspaper released a video of brain surgery performed by Slyusarchuk, surrounded by assistants in an operating room; in the video, he wiped his scalpel with cotton wool before incising the patient's brain. On 14 March Ekspres published an interview with Andriy Novosad, who told reporters that he wrote a computer program which Slyusarchuk tested with radio equipment for the pi demonstrations and created articles which were published in Slyusarchuk's name. After the Ekspres articles attracted widespread publicity Slyusarchuk denied the accusations in interviews for other media sources, saying that he had applied to the General Prosecutor of Ukraine to clarify the situation and disprove the Ekspres allegations. On 14 November 2011, the Ukrainian police detained him on suspicion of forgery and fraud. During the investigation, senior officials of the Ministry of Education and Science, Youth and Sport of


id: andriy-slyusarchuk-20260505-6
file: data/en.wikipedia.org/wiki/Andriy_Slyusarchuk-6.md
category: reference
title: Andriy Slyusarchuk
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Andriy_Slyusarchuk
date_saved: 2026-05-05T09:31:06.020817+00:00
instance: kb-cron
parent: andriy-slyusarchuk-20260505-0
summary:
== Conviction and sentencing == In the Verkhovna Rada, Slyusarchuk's activities were called "the largest-scale fraud in the 20 years of Ukrainian independence". According to the Ukrainian Independent Information Agency, his defrauding of government agencies is unprecedented. In 2012, Ukrainsky Medychny Chasopys (Ukrainian Medical Journal) published the outcome of his case entitled, "Head doctors who let the person without medical training into operating room should be held criminally responsible." In the article, Ukrainian psychiatrist Semyon Gluzman expressed the opinion that Slyusarchuk skillfully took advantage of poor security; if he had chosen a lower-profile specialty, he might have succeeded. According to Gluzman, Ukraine has hundreds of people with the degree of Doctor of Sciences with expertise comparable to Slyusarchuk's. In the journal, Doctor of Science Olga Bogomolets wrote that the admission of a person without medical training to an operating room violated laws clearly regulating who can practice medicine, when and where; a hospital supervising physician who violates the law must be held accountable. On 14 February 2014, the Sykhiv Raion Court sentenced Slyusarchuk to eight years in prison after finding him guilty of five counts of illegal medical activities and two counts of murder by negligence: a 52-year-old man named


id: sokal-affair-20260505-0
file: data/en.wikipedia.org/wiki/Sokal_affair-0.md
category: reference
title: Sokal affair
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Sokal_affair
date_saved: 2026-05-05T09:31:07.214905+00:00
instance: kb-cron
parent: sokal-affair-20260505-0
summary:
The Sokal affair, also known as the Sokal hoax, was a demonstrative scholarly hoax performed by Alan Sokal, a physics professor at New York University and University College London. In 1996, Sokal submitted an article to Social Text, an academic journal of cultural studies. The submission was an experiment to test the journal's intellectual rigor, specifically to investigate whether "a leading North American journal of cultural studies—whose editorial collective includes such luminaries as Fredric Jameson and Andrew Ross—[would] publish an article liberally salted with nonsense if (a) it sounded good and (b) it flattered the editors' ideological preconceptions." The article, "Transgressing the Boundaries: Towards a Transformative Hermeneutics of Quantum Gravity", was published in the journal's Spring/Summer 1996 "Science Wars" issue. It proposed that quantum gravity is a social and linguistic construct. The journal did not practice academic peer review at the time, so it did not submit the article for outside expert review by a physicist. Three weeks after its publication in May 1996, Sokal revealed in the magazine Lingua Franca that the article was a hoax. The hoax caused controversy about the scholarly merit of commentary on the physical sciences by those in the humanities; the influence of postmodern


id: sokal-affair-20260505-1
file: data/en.wikipedia.org/wiki/Sokal_affair-1.md
category: reference
title: Sokal affair
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Sokal_affair
date_saved: 2026-05-05T09:31:07.214905+00:00
instance: kb-cron
parent: sokal-affair-20260505-0
summary:
=== Follow-up between Sokal and the editors === In the article "A Physicist Experiments With Cultural Studies" in the May 1996 issue of Lingua Franca, Sokal revealed that "Transgressing the Boundaries" was a hoax and concluded that Social Text "felt comfortable publishing an article on quantum physics without bothering to consult anyone knowledgeable in the subject" because of its ideological proclivities and editorial bias. In their defense, Social Text's editors said they believed that Sokal's essay "was the earnest attempt of a professional scientist to seek some kind of affirmation from postmodern philosophy for developments in his field" and that "its status as parody does not alter, substantially, our interest in the piece, itself, as a symptomatic document." Besides criticizing his writing style, Social Text's editors accused Sokal of behaving unethically in deceiving them. Sokal said the editors' response demonstrated the problem that he sought to identify. Social Text, as an academic journal, published the article not because it was faithful, true, and accurate to its subject, but because an "academic authority" had written it and because of the appearance of the obscure writing. The editors said they considered it poorly written but published it because they felt Sokal was


id: sokal-affair-20260505-2
file: data/en.wikipedia.org/wiki/Sokal_affair-2.md
category: reference
title: Sokal affair
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Sokal_affair
date_saved: 2026-05-05T09:31:07.214905+00:00
instance: kb-cron
parent: sokal-affair-20260505-0
summary:
=== Criticism of social sciences === Sociologist Stephen Hilgartner, chairman of Cornell University's science and technology studies department, wrote "The Sokal Affair in Context" (1997), comparing Sokal's hoax to "Confirmational Response: Bias Among Social Work Journals" (1990), an article by William M. Epstein published in Science, Technology, & Human Values. Epstein used a similar method to Sokal's, submitting fictitious articles to real academic journals to measure their response. Though much more systematic than Sokal's work, it received scant media attention. Hilgartner argued that the "asymmetric" effect of the successful Sokal hoax compared with Epstein's experiment cannot be attributed to its quality, but that "[t]hrough a mechanism that resembles confirmatory bias, audiences may apply less stringent standards of evidence and ethics to attacks on targets that they are predisposed to regard unfavorably." As a result, according to Hilgartner, though competent in terms of method, Epstein's experiment was largely muted by the more socially accepted social work discipline he critiqued, while Sokal's attack on cultural studies, despite lacking experimental rigor, was accepted. Hilgartner also argued that Sokal's hoax reinforced the views of well-known pundits such as George Will and Rush Limbaugh, so that his opinions were amplified by media outlets predisposed to


id: song-yoo-geun-20260505-0
file: data/en.wikipedia.org/wiki/Song_Yoo-geun-0.md
category: reference
title: Song Yoo-geun
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Song_Yoo-geun
date_saved: 2026-05-05T09:31:08.408373+00:00
instance: kb-cron
parent: song-yoo-geun-20260505-0
summary:
Song Yoo-geun (born November 27, 1997) is a South Korean person who gained recognition as a child prodigy in South Korea since 2004. After graduating college in 2009, he was involved in a number of controversies during his ultimately unsuccessful doctorate program at Korean University of Science and Technology (UST), including one involving his paper in October 2015 written with his advisor, Park Seok-jae. The paper, entitled "Axisymmetric, Nonstationary Black Hole Magnetospheres: Revisited" appeared in the Astrophysical Journal (ApJ). However, the paper was soon retracted due to concerns that it plagiarized a 2002 book chapter. == Life before October 2015 == Song Yoo-geun left a prodigy school he attended in 2003. Six months of independent study enabled him to solve pre-calculus problems. In August 2004, at age 6, he passed the "Craftsman Information Processing" (정보처리기능사) certification examination. In November of the same year, his parents tried to enroll him at a local elementary school (Shim Seok Elementary School; 심석초등학교) as a sixth grader. While Song did not perform well, obtaining a score of 12% on his math exam, his parents maintained that Song was neither used to, or interested in, calculating equations that lacked meaning. Although the school allowed this


id: song-yoo-geun-20260505-1
file: data/en.wikipedia.org/wiki/Song_Yoo-geun-1.md
category: reference
title: Song Yoo-geun
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Song_Yoo-geun
date_saved: 2026-05-05T09:31:08.408373+00:00
instance: kb-cron
parent: song-yoo-geun-20260505-0
summary:
Song & Park (2015) draws extensively from an earlier publication by Park, "Stationary Versus Nonstationary Force-Free Black Hole Magnetospheres," in Black Hole Astrophysics 2002: Proceedings of the Sixth APCTP Winter School (World Scientific Publishing Co., 2002). In fact, the differences are modest, mostly confined to an alternate formulation of the analytic results, and could raise the question of copyright violation. Park (2002) is not part of the peer-reviewed literature, and scientists frequently use a conference proceeding as the rough draft of a subsequent submission to a professional peer-reviewed journal. However, in this case the overlap between the 2002 book chapter and 2015 paper is exceptionally large. "This article by Yoo Geun Song & Seok Jae Park has been retracted at the request of the Editor-in-Chief due to an unacceptably large overlap with "Stationary Versus Nonstationary Force-Free Black Hole Magnetospheres," published in Black Hole Astrophysics 2002: Proceedings of the Sixth APCTP Winter School (World Scientific Publishing Co., 2002). Please see https://aas.org/posts/news/2015/11/astrophysical-journal-paper-retracted-plagiarism for a more complete explanation." Park first denied the plagiarism controversy towards Song, insisting he will "resign his position if any part of his paper is found unoriginal." He also argued that Song's work on partial differential equation is totally


id: stimulus-triggered-acquisition-of-pluripotency-20260505-0
file: data/en.wikipedia.org/wiki/Stimulus-triggered_acquisition_of_pluripotency-0.md
category: reference
title: Stimulus-triggered acquisition of pluripotency
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Stimulus-triggered_acquisition_of_pluripotency
date_saved: 2026-05-05T09:31:09.670612+00:00
instance: kb-cron
parent: stimulus-triggered-acquisition-of-pluripotency-20260505-0
summary:
Stimulus-triggered acquisition of pluripotency (STAP) was a proposed method of generating pluripotent stem cells by subjecting ordinary cells to certain types of stress, such as the application of a bacterial toxin, submersion in a weak acid, or physical trauma. The technique gained prominence in January 2014 when research by Haruko Obokata et al. was published in Nature. Over the following months, all scientists who tried to duplicate her results failed, and suspicion arose that Obokata's results were due to error or fraud. An investigation by her employer, RIKEN, was launched. On April 1, 2014, RIKEN concluded that Obokata had falsified data to obtain her results. On June 4, 2014, Obokata agreed to retract the papers. On August 5, 2014, Yoshiki Sasai—Obokata's supervisor at RIKEN and one of the coauthors on the STAP cell papers—was found dead at a RIKEN facility after an apparent suicide by hanging. STAP would have been a radically simpler method of stem cell generation than previously researched methods as it requires neither nuclear transfer nor the introduction of transcription factors. == Overview == Haruko Obokata claimed that STAP cells were produced by exposing CD45+ murine spleen cells to certain stresses including an acidic medium with a


id: stimulus-triggered-acquisition-of-pluripotency-20260505-1
file: data/en.wikipedia.org/wiki/Stimulus-triggered_acquisition_of_pluripotency-1.md
category: reference
title: Stimulus-triggered acquisition of pluripotency
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Stimulus-triggered_acquisition_of_pluripotency
date_saved: 2026-05-05T09:31:09.670612+00:00
instance: kb-cron
parent: stimulus-triggered-acquisition-of-pluripotency-20260505-0
summary:
=== Investigation into disputed claims === In the months after the two Nature papers were released, all scientists who tried to duplicate Obokata's results failed and suspicion arose that her results were due to error or fraud. An investigation into alleged irregularities was launched by RIKEN on February 15, 2014. The allegations questioned the use of seemingly duplicated images in the papers, and reported failure to reproduce her results in other prominent stem-cell laboratories. Nature also announced that they were investigating. Several stem-cell scientists defended Obokata or reserved their opinion while the investigation was ongoing. To address the problem of reproducibility in other laboratories, Obokata published some technical 'tips' on the protocols on March 5 while promising that the detailed procedure would be published in due course. On March 11, Teruhiko Wakayama, one of Obokata's coauthors, urged all the researchers involved to withdraw the articles, citing many "questionable points". Charles Vacanti said he opposed their retraction and posted a "revised protocol" for creating STAP cells on his own website, which was taken down after he resigned his BWH post. On March 14, RIKEN released an interim report of the investigation. Out of the six items being investigated, the committee concluded


id: john-alfred-talent-20260505-0
file: data/en.wikipedia.org/wiki/John_Alfred_Talent-0.md
category: reference
title: John Alfred Talent
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/John_Alfred_Talent
date_saved: 2026-05-05T09:31:10.795081+00:00
instance: kb-cron
parent: john-alfred-talent-20260505-0
summary:
John Alfred Talent (18 October 1932 – 27 March 2024) was an Australian palaeontologist whose research and teaching career was spent largely at Macquarie University in Sydney, Australia. He is remembered particularly for leading the effort in the 1980s and 1990s to expose the large body of fraudulent publications by Vishwa Jit Gupta of Panjab University, which is collectively known as the Himalayan fossil hoax. == Biography == Talent was born to Alfred George Talent and Thelma Emily (née Henderson) at Ascot Vale, Victoria. He studied science at the University of Melbourne, graduating in science with majors in geology, chemistry and mathematics in 1953 and completing his master's degree in 1955 with a dissertation on Studies in the stratigraphy and paleontology of some paleozoic limestones of Eastern Victoria. He obtained a PhD in 1959 on the thesis Contributions to the stratigraphy and palaeontology of the Silurian and Devonian of Gippsland. He followed this in 1966 by taking a bachelor of arts degree in 1966 with majors in French and fine arts, and a minor in Arabic. Talent was awarded the a post-doctoral fellowship from the Commonwealth Scientific and Industrial Research Organisation (CSIRO) with which he spent time in Brussels, Belgium,


id: thiotimoline-20260505-0
file: data/en.wikipedia.org/wiki/Thiotimoline-0.md
category: reference
title: Thiotimoline
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Thiotimoline
date_saved: 2026-05-05T09:31:11.958549+00:00
instance: kb-cron
parent: thiotimoline-20260505-0
summary:
Thiotimoline is a fictitious chemical compound conceived by American biochemist and science fiction author Isaac Asimov. It was first described in a spoof scientific paper titled "The Endochronic Properties of Resublimated Thiotimoline" in 1948. The major peculiarity of the chemical is its "endochronicity": it starts dissolving before it makes contact with water. Asimov went on to write three additional short stories, each describing different properties or uses of thiotimoline. == Chemical properties == In Asimov's writings the endochronicity of thiotimoline is explained by the fact that in the thiotimoline molecule, there is at least one carbon atom such that, while two of the carbon's four chemical bonds lie in normal space and time, one of the bonds projects into the future and another into the past. Thiotimoline is derived from the bark of the (fictitious) shrub Rosacea karlsbadensis rufo, and the thiotimoline molecule includes at least fourteen hydroxy groups, two amino groups, and one sulfonic acid group, and possibly one nitro compound group as well. The nature of the hydrocarbon nucleus is unknown, although it seems in part to be an aromatic hydrocarbon. == Background == In 1947 Asimov was engaged in doctoral research in chemistry and, as part of


id: thiotimoline-20260505-1
file: data/en.wikipedia.org/wiki/Thiotimoline-1.md
category: reference
title: Thiotimoline
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Thiotimoline
date_saved: 2026-05-05T09:31:11.958549+00:00
instance: kb-cron
parent: thiotimoline-20260505-0
summary:
== "Thiotimoline and the Space Age" == Asimov wrote a third thiotimoline article on 14 November 1959 called "Thiotimoline and the Space Age". Instead of a fake scientific paper, this third article took the form of an address by Asimov to the 12th annual meeting of the American Chronochemical Society, a nonexistent scientific society. In his address, Asimov "describes" his first experiments with thiotimoline in July 1947, and timing the compound's dissolution with the original endochronometer, "the same instrument now at the Smithsonian". Asimov laments the skepticism with which chronochemistry has been greeted in America, noting with sorrow that his address has only attracted fifteen attendees. He then contrasts the thriving state of chronochemistry in the Soviet Union, with the research town of Khrushchevsk, nicknamed "Tiotimolingrad", established in the Urals. According to Asimov, two Scottish researchers have developed a "telechronic battery", which uses a series of 77,000 interconnected endochronometers to allow a final sample of thiotimoline to dissolve up to a day before water is added to an initial sample. Asimov says there is "strong, if indirect, evidence that the Soviet Union possesses even more sophisticated devices and is turning them out in commercial quantities". He believes that the Soviets


id: thiotimoline-20260505-2
file: data/en.wikipedia.org/wiki/Thiotimoline-2.md
category: reference
title: Thiotimoline
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Thiotimoline
date_saved: 2026-05-05T09:31:11.958549+00:00
instance: kb-cron
parent: thiotimoline-20260505-0
summary:
== Other references to thiotimoline == In Glen Bever's story "And Silently Vanish Away" a chemist with the unique ability to use psychokinetic catalysis to speed up difficult reactions is shocked by a lab explosion and the mixture he was working on gets changed. Under analysis the structure never appears to be the same twice and when the substance is injected into lab rats they start to silently and suddenly vanish. It is found that one part of the compound is a molecule which spreads out into four dimensions. The four-dimensional molecule is thiotimoline. The story appeared in the November 1971 issue of Analog Science Fiction/Science Fact. Topi H. Barr's story "Antithiotimoline" deals with a chemist who accidentally creates a thiotimoline-like compound which extrudes only into the past, enabling the scientist to create images of past events. The narrator complains that thiotimoline is extremely difficult to obtain, and suspects that the CIA or other agencies are controlling the supply for their own reasons. The story appeared in the December 1977 issue of Analog. Spider Robinson's story "Mirror mirror, off the wall", published in Time Travelers Strictly Cash in 1981, also references thiotimoline. In Robert Silverberg's 1989 story "The Asenion Solution",


id: time-travel-claims-and-urban-legends-20260505-0
file: data/en.wikipedia.org/wiki/Time_travel_claims_and_urban_legends-0.md
category: reference
title: Time travel claims and urban legends
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Time_travel_claims_and_urban_legends
date_saved: 2026-05-05T09:31:13.108313+00:00
instance: kb-cron
parent: time-travel-claims-and-urban-legends-20260505-0
summary:
Multiple accounts of people who allegedly travelled through time have been reported by the press or circulated online. These reports have turned out to be either hoaxes or else based on incorrect assumptions, incomplete information, or interpretation of fiction as fact. Many are now recognized as urban legends. == Alleged time travelers == === Charlotte Anne Moberly and Eleanor Jourdain === In 1911, Charlotte Anne Moberly (1846–1937) and Eleanor Jourdain (1863–1924) published a book entitled An Adventure, under the names of "Elizabeth Morison" and "Frances Lamont". They described a visit to the Petit Trianon, a small château in the grounds of the Palace of Versailles, where they claimed they saw ghosts, including that of Marie Antoinette and others. Their story caused a sensation but was not taken seriously. === "Chaplin's Time Traveller" === In October 2010, Northern Irish filmmaker George Clarke uploaded a video clip entitled "Chaplin's Time Traveller" to YouTube. The clip analyzes bonus material in a DVD of the Charlie Chaplin film The Circus. Included in the DVD is footage from the film's Los Angeles premiere at Grauman's Chinese Theatre in 1928. At one point, a woman is seen walking by, holding up an object to her ear.


id: time-travel-claims-and-urban-legends-20260505-1
file: data/en.wikipedia.org/wiki/Time_travel_claims_and_urban_legends-1.md
category: reference
title: Time travel claims and urban legends
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Time_travel_claims_and_urban_legends
date_saved: 2026-05-05T09:31:13.108313+00:00
instance: kb-cron
parent: time-travel-claims-and-urban-legends-20260505-0
summary:
=== Mike "Madman" Marcum === In 1995, a caller to Art Bell's syndicated radio show Coast to Coast AM named Mike Marcum claimed to have discovered a means of time travel using a Jacob's ladder. In attempting to build a larger version of this device, Marcum admitted that he had stolen several power transformers from the local power company, St. Joseph Light and Power in King City, Missouri; in using them to power his "time machine" he caused a local blackout that brought him to the attention of authorities. Police records confirmed that he had been arrested for this theft and sentenced to 60 days in jail plus a suspended sentence. He called the radio show again in 1996, stating he was building a second "time machine" from legally acquired parts, and was 30 days from completing the device. He claimed to have sent around 200 items and small animals through this device and announced that he would travel through it himself. Marcum then "disappeared" in 1997. His absence led to a number of theories, as well as giving birth to a number of urban legends. In 2015, Bell interviewed him again on his radio show, Midnight in the Desert,


id: time-travel-claims-and-urban-legends-20260505-2
file: data/en.wikipedia.org/wiki/Time_travel_claims_and_urban_legends-2.md
category: reference
title: Time travel claims and urban legends
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Time_travel_claims_and_urban_legends
date_saved: 2026-05-05T09:31:13.108313+00:00
instance: kb-cron
parent: time-travel-claims-and-urban-legends-20260505-0
summary:
=== Håkan Nordkvist === A video uploaded in 2006 shows a Swedish man named Håkan Nordkvist claiming he was accidentally transported to 2046 while attempting to fix the sink in his kitchen. There in the future, he immediately met someone who turned out to be himself, about 70 years old, and with whom he "had a great time". He filmed short footage of the two smiling and hugging each other and showing the tattoo they had on their right arms. The story was part of a marketing campaign promoting the insurance company's pension plans. === iPhone in a 1860 painting === Some online viewers claimed that an 1860 painting by Austrian artist Ferdinand Georg Waldmüller titled The Expected depicted a woman holding a mobile phone and staring down at it while strolling along a country path. However, art experts debunked these claims, stating that the alleged mobile phone the woman was holding in the painting was actually a prayer book. == Alleged time-travel technology == === Die Glocke === Die Glocke ("The Bell") is a purported Nazi time machine that was supposedly part of a flying saucer. === The Chronovisor === Italian Benedictine monk Pellegrino Ernetti claimed to have used


id: tr-ara-a-20260505-0
file: data/en.wikipedia.org/wiki/TR_Araña-0.md
category: reference
title: TR Araña
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/TR_Araña
date_saved: 2026-05-05T09:31:14.304013+00:00
instance: kb-cron
parent: tr-ara-a-20260505-0
summary:
The TR Araña (Spanish, meaning "route tracing spider") is a robot that is claimed to remotely analyse the composition of the ground. The device was created by Chilean inventor Manuel Salinas and was reported to be able to operate at depths of up to 50 metres. It is widely believed by the scientific community to be a fraud. == Principles == Answering a request by the Chilean Commission on Nuclear Energy, Salinas wrote the following paragraph: "[The principle behind the robot is] The non linear integration of the basic unit of life conformation the way it is known; therefore and merely as a functional and explanatory concept, I detail that our device is the integration of highly sophisticated electronic components which are able to decipher the unanimity equation in the chaos theory in the context of an integral raised to the power of the radical exponent, based in the conformation of the species, the way they are known after 20,000 years of assisted evolution." At a presentation to students, physicists, and engineers at the Universidad Técnica Federico Santa María in Valparaíso, Chile, on 12 October 2005, Salinas gave improbable and seemingly irrational theories to explain how his machine worked. He


id: trixolan-20260505-0
file: data/en.wikipedia.org/wiki/Trixolan-0.md
category: reference
title: Trixolan
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Trixolan
date_saved: 2026-05-05T09:31:15.442248+00:00
instance: kb-cron
parent: trixolan-20260505-0
summary:
Trixolan (TX) is a purportedly therapeutic agent based on Viroxan, a citronella-based substance used by Stephen Herman, a Californian doctor who used it to treat AIDS patients. State medical officials stated that the drug hastened the deaths of at least two AIDS patients. Herman surrendered his medical license in 1991 when prosecutors agreed they would, in return, drop civil charges of gross negligence, incompetence, dishonesty and other offenses. In 1994, in the first AIDS medical fraud case to come to trial in the United States, a Los Angeles County jury ordered two doctors and a hospital that used Viroxan to pay five patients a total of $2.7 million. Herman had been dropped from the suit when he declared bankruptcy. Trixolan was linked in headlines to American fugitive Robert Lee Vesco and to Donald A. Nixon, President Richard Nixon's nephew. In the early 1980s Donald Nixon's wife contracted breast cancer and was treated with chemotherapy. In the search for a remedy for her cancer, he met with Dr. Stephen Herman, who claimed that Viroxan could boost the immune system and could get rid of many diseases, including cancer. Donald Nixon gave his wife Trixolan and claimed that it cured his wife's


id: the-truth-about-hansel-and-gretel-20260505-0
file: data/en.wikipedia.org/wiki/The_Truth_About_Hansel_and_Gretel-0.md
category: reference
title: The Truth About Hansel and Gretel
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/The_Truth_About_Hansel_and_Gretel
date_saved: 2026-05-05T09:31:16.605846+00:00
instance: kb-cron
parent: the-truth-about-hansel-and-gretel-20260505-0
summary:
The Truth About Hansel and Gretel (German: Die Wahrheit über Hänsel und Gretel) is a 1963 book written by German children's author and humorist Hans Traxler, which described how an amateur archaeologist named Georg Ossegg uncovered evidence that the story about Hansel and Gretel was based on real events, just as Heinrich Schliemann discovered the city of Troy from Ancient Greek legends. The book immediately became a bestseller, but in several months Traxler confessed it was a hoax. == Summary == According to the book, Ossegg determined that the fairytale, Hansel and Gretel, was based on the story of a 17th-century baker named Hans Metzler and his sister Grete. Hans and Grete Metzler lived in a village in the Spessart Forest during the Thirty Years' War, and killed a woman named Katharina Schraderin in order to steal her recipe for Nürnberger Lebkuchen (gingerbread). In reality, Ossegg did not exist and the details of the story were fabricated by Traxler. Vanessa Joosen has called the book a "fictive nonfictional text", which "carries the features of a nonfictional text but consciously misleads the reader". == In popular culture == Despite its fictional nature, the hoax convinced many in Germany at the time,


id: turbo-encabulator-20260505-0
file: data/en.wikipedia.org/wiki/Turbo_encabulator-0.md
category: reference
title: Turbo encabulator
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Turbo_encabulator
date_saved: 2026-05-05T09:31:17.763732+00:00
instance: kb-cron
parent: turbo-encabulator-20260505-0
summary:
The turbo encabulator is a fictional electromechanical machine with a satirical technobabble description that became a famous in-joke among engineers after a report about it by John Quick was published by the British Institution of Electrical Engineers in their Students' Quarterly Journal in 1944. Technical documentation has been written for the non-existent machine, and there are a number of parody marketing videos. ...The original machine had a base-plate of prefamulated amulite, surmounted by a malleable logarithmic casing in such a way that the two main spurving bearings were in a direct line with the pentametric fan. The latter consisted simply of six hydrocoptic marzlevanes, so fitted to the ambifacient lunar waneshaft that side fumbling was effectively prevented. The main winding was of the normal lotus-o-delta type placed in panendermic semi-boloid slots in the stator, every seventh conductor being connected by a non-reversible tremie pipe to the differential girdlespring on the "up" end of the grammeters... == History == An early popular American reference to the turbo encabulator appeared in an article by New York lawyer Bernard Salwen in the April 15, 1946, issue of Time magazine. Part of Salwen's job was to review technical manuscripts, including an Arthur D. Little


id: villejuif-leaflet-20260505-0
file: data/en.wikipedia.org/wiki/Villejuif_leaflet-0.md
category: reference
title: Villejuif leaflet
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Villejuif_leaflet
date_saved: 2026-05-05T09:31:18.923543+00:00
instance: kb-cron
parent: villejuif-leaflet-20260505-0
summary:
The Villejuif leaflet, also known as the Villejuif flyer and the Villejuif list, was a pamphlet which enjoyed wide distribution. The leaflet listed a number of safe food additives with their E numbers as alleged carcinogens. The leaflet caused mass panic in Europe in the late 1970s and 1980s. One of the entries on the list was citric acid (E330). Its name derives from its false claim to have been produced at the hospital in Villejuif. == History == The earliest known sighting of the leaflet was in February 1976, in the form of a single typewritten page in France. Homemade copies were spread across Europe for a decade in the form of a leaflet or flyer pamphlet that was distributed between friends and apart from citric acid included 16 other chemicals in a list of substances that it called dangerous toxins and carcinogens. The original author of the typewritten list was never found, and the leaflet affected about 7 million people in its uncontrollable propagation. In a survey of 150 housewives, 19% said they have stopped buying these brands, and 69% planned to do so. == List contents == Multiple versions of this leaflet circulated, the exact set of


id: well-to-hell-20260505-0
file: data/en.wikipedia.org/wiki/Well_to_Hell-0.md
category: reference
title: Well to Hell
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Well_to_Hell
date_saved: 2026-05-05T09:31:20.105350+00:00
instance: kb-cron
parent: well-to-hell-20260505-0
summary:
The "Well to Hell", also known as the "Siberian hell sounds", is an urban legend regarding a putative borehole in the Siberian region of Russia, which was purportedly drilled so deep that it broke through into Hell. == Legend and basis == The legend holds that a team of Soviet engineers purportedly led by an individual named "Mr. Azakov" in an unnamed place in Siberia had drilled a hole that was 14.4 km (9 miles) deep before breaking through to a cavity. Intrigued by this unexpected discovery, they lowered an extremely heat-tolerant microphone, along with other sensory equipment, into the well. The temperature deep within was 1,000 °C (1,800 °F), heat from a chamber of fire from which screaming could be heard. The Soviet Union had, in fact, drilled a hole more than 12 km (7.5 miles) deep, the Kola Superdeep Borehole, located not in Siberia but on the Kola Peninsula, which shares borders with Norway and Finland. Upon reaching the depth of 12,262 m (40,230 feet) in 1989, geological anomalies were found, although they reported no supernatural encounters. The recording of "tormented screams" was later found to be looped together from various sound effects, sometimes identified as the soundtrack


id: when-contact-changes-minds-20260505-0
file: data/en.wikipedia.org/wiki/When_Contact_Changes_Minds-0.md
category: reference
title: When Contact Changes Minds
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/When_Contact_Changes_Minds
date_saved: 2026-05-05T09:31:21.307446+00:00
instance: kb-cron
parent: when-contact-changes-minds-20260505-0
summary:
"When Contact Changes Minds: An Experiment on Transmission of Support for Gay Equality" is a fraudulent article by then-UCLA political science graduate student Michael LaCour and Columbia University political science professor Donald Green. The article was published in the academic journal Science in December 2014, and retracted in May 2015 after it emerged that the data in the study had been forged by LaCour. The article purported to demonstrate that people's minds on the issue of gay marriage could be changed by conversations with gay canvassers, but not with straight canvassers. == Study == The authors claimed to have investigated whether gay or straight messengers were effective at encouraging voters to support same-sex marriage and whether attitude change persisted and spread to others in voters’ social networks. The purported results, measured by an unrelated panel survey, show that both gay and straight canvassers produced large effects initially, but only gay canvassers’ effects persisted in 3-week, 6-week, and 9-month follow-ups. LaCour and Green (2014) also found strong evidence of within-household transmission of opinion change, but only in the wake of conversations with gay canvassers. The article is ranked in the top 5% of all research output, as scored using Altmetrics. The


id: when-contact-changes-minds-20260505-1
file: data/en.wikipedia.org/wiki/When_Contact_Changes_Minds-1.md
category: reference
title: When Contact Changes Minds
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/When_Contact_Changes_Minds
date_saved: 2026-05-05T09:31:21.307446+00:00
instance: kb-cron
parent: when-contact-changes-minds-20260505-0
summary:
== Falsified data == The "When contact changes minds" study was discredited after a critique by David Broockman, Joshua Kalla, and Peter Aronow on May 19, 2015, titled "Irregularities in LaCour (2014)", concluded that the data had been falsified and no data had been collected. The survey company that LaCour claimed to have used denied performing any work for the study and did not have an employee by the name LaCour listed as his contact with the company. In addition, LaCour had claimed that participants were paid using outside funding, but no organization could be found that had provided the amount of money required to pay thousands of people. The "Irregularities" paper also identified the likely method by which LaCour had forged the data. The baseline survey results appeared to have been taken from an earlier dataset called the Cooperative Campaign Analysis Project (CCAP), to which LaCour had access. The later sets of data appeared to have been simulated from the first using statistical methods to shift the results and by adding normally distributed noise. In addition, the paper noted that canvasser identifiers were missing from the results, making it impossible to verify whether different canvassers produced different results as


id: when-contact-changes-minds-20260505-2
file: data/en.wikipedia.org/wiki/When_Contact_Changes_Minds-2.md
category: reference
title: When Contact Changes Minds
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/When_Contact_Changes_Minds
date_saved: 2026-05-05T09:31:21.307446+00:00
instance: kb-cron
parent: when-contact-changes-minds-20260505-0
summary:
== Popular press == While Green, David Broockman, and Joshua Kalla conducted numerous interviews with reporters outlining their version of events, LaCour refrained from talking to the media with the exception of a single interview with The New York Times. Various opinions were advanced in the popular media regarding the implications of the scandal and the motivations of the parties involved. The editorial page of The Wall Street Journal speculated that LaCour's argument originally gained acceptance in the scientific community because it "flattered the ideological sensibilities of liberals, who tend to believe that resistance to gay marriage can only be the artifact of ignorance or prejudice, not moral or religious conviction. Mr. LaCour's findings let them claim that science had proved them right." The Journal editorial further argued that the paper and its acceptance reflected a broader phenomenon in the social sciences in which liberals, according to the editorial, "recast stubborn political debates about philosophy and values as disputes over facts that can be resolved by science". New York Magazine columnist Jesse Singal dismissed the Wall Street Journal editorial, arguing that it was silly and uninformed, and suggested instead that the main reason for the article's publication was its contradiction


id: when-prophecy-fails-20260505-0
file: data/en.wikipedia.org/wiki/When_Prophecy_Fails-0.md
category: reference
title: When Prophecy Fails
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/When_Prophecy_Fails
date_saved: 2026-05-05T09:31:22.517812+00:00
instance: kb-cron
parent: when-prophecy-fails-20260505-0
summary:
When Prophecy Fails: A Social and Psychological Study of a Modern Group That Predicted the Destruction of the World is a classic work of social psychology by Leon Festinger, Henry Riecken, and Stanley Schachter, published in 1956, detailing a study of a small UFO religion in Chicago called the Seekers that believed in an imminent apocalypse. The authors took a particular interest in the members' coping mechanisms after the event did not occur, focusing on the cognitive dissonance between the members' beliefs and actual events, and the psychological consequences of these disconfirmed expectations. Later archival work has alleged that many of the book's core claims are based on fabrications or exaggerations. == Overview == Festinger, Riecken, and Schachter were already studying the effects of prophecy disconfirmation on groups of believers when they read a story in a local newspaper headlined "Prophecy from Planet. Clarion Call to City: Flee That Flood. It'll Swamp us on Dec. 21". The prophecy came from Dorothy Martin (1900–1992), a Chicago housewife who practised automatic writing, and it outlined a catastrophe predicted for a specific date in their near future. Seeing an opportunity to test their theories with a contemporary case study, the research team infiltrated


id: when-prophecy-fails-20260505-1
file: data/en.wikipedia.org/wiki/When_Prophecy_Fails-1.md
category: reference
title: When Prophecy Fails
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/When_Prophecy_Fails
date_saved: 2026-05-05T09:31:22.517812+00:00
instance: kb-cron
parent: when-prophecy-fails-20260505-0
summary:
=== Methodology === The study was principally qualitative in nature, with data collected through participant observation, without the permission of the people being observed. The authors of the study and a selection of paid observers infiltrated groups of believers in two locations, in order to collect data as trusted insiders. Posing as people with a genuine personal interest in flying saucers and the group's belief system, the observers built rapport with the group members, aiming to take as passive a role as possible whilst gathering information on the group. Between them, the observers aimed to be present at all key events. Following each notable occurrence, each observer would attempt to excuse themselves in order to write up their notes or record them on audiotape while their memory was still fresh. They would record their notes in a variety of locations, including the bathroom of the house, the porch, or in a nearby hotel room that had been rented for the purpose. In addition to their own notes, the observers collected artifacts such as originals or copies of automatic writing produced by Martin, and transcripts of taped telephone calls that the research subjects themselves had recorded and lent to the observers.


id: when-prophecy-fails-20260505-2
file: data/en.wikipedia.org/wiki/When_Prophecy_Fails-2.md
category: reference
title: When Prophecy Fails
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/When_Prophecy_Fails
date_saved: 2026-05-05T09:31:22.517812+00:00
instance: kb-cron
parent: when-prophecy-fails-20260505-0
summary:
December 17. Ms. Keech received a phone call from person identifying himself as "Captain Video" from outer space, telling her that a saucer was to land in her backyard to pick her up at 4 o'clock in the afternoon. (Festinger considers this call to have been made by a practical joker reacting to press coverage of Keech's group.) Some of the group initially questioned the call, before accepting it and preparing themselves to be collected by the saucer, removing all metal objects from their persons. By 5:30 pm the group appeared to have given up, and were reluctant to discuss the issue of why the saucer had not arrived. When the matter was discussed, they agreed that the event had been a practice session. Ms. Keech received another message later that day that the saucer would pick them up at 1:30 am. The group waited for the saucer until 3:30 am then gave up. Before December 20. The group shuns publicity. Interviews are given only grudgingly. Access to Keech's house is only provided to those who can convince the group that they are true believers. The group evolves a belief system – provided by the automatic writing from the planet


id: f-d-c-willard-20260505-0
file: data/en.wikipedia.org/wiki/F._D._C._Willard-0.md
category: reference
title: F. D. C. Willard
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/F._D._C._Willard
date_saved: 2026-05-05T09:31:24.902918+00:00
instance: kb-cron
parent: f-d-c-willard-20260505-0
summary:
F. D. C. Willard (1968–1982) was the pen name of Chester, a Siamese cat, used on several papers written by his owner, J. H. Hetherington, in physics journals. On one occasion, he was listed as the sole author. == Background == In 1975, the American physicist and mathematician Jack H. Hetherington of Michigan State University wanted to publish some of his research results in the field of low-temperature physics in the scientific journal Physical Review Letters. A colleague, to whom he had given his paper for review, pointed out that Hetherington had used the first person plural, "we", in his text, and that the journal would reject this form on submissions with a sole author. Rather than take the time to retype the article to use the singular form, or to bring in a co-author, Hetherington decided to invent one. == Publications == Hetherington had a Siamese cat named Chester, who had been sired by a Siamese named Willard. Fearing that colleagues might recognize his pet's name, he thought it better to use the pet's initial. Aware that most Americans have at least two given names, he invented two more given names based on the scientific name for a house


id: bibliothek-des-konservatismus-20260505-0
file: data/en.wikipedia.org/wiki/Bibliothek_des_Konservatismus-0.md
category: reference
title: Bibliothek des Konservatismus
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Bibliothek_des_Konservatismus
date_saved: 2026-05-05T09:31:26.409809+00:00
instance: kb-cron
parent: bibliothek-des-konservatismus-20260505-0
summary:
The Library of Conservatism (German: Bibliothek des Konservatismus (BdK)) is a specialized scientific library and think tank in Berlin. Its focus is non-fiction literature by conservative, right-wing and libertarian authors from the 18th to the early 21st century. The principal foundation for the library was laid by the writer and publicist Caspar von Schrenck-Notzing who gave his extensive private collection of books. The BdK opened in 2012 in Berlin. So far, its catalogued stock comprises around 35,000 items. The library is financed and supported by the Foundation for Conservative Education and Research (Förderstiftung Konservative Bildung und Forschung, FKBF). == Establishment == The writer and publicist Caspar von Schrenck-Notizing (1927–2009) was the scion of an old Bavarian family and a bestselling author and conservative critique in post-war Germany, who founded the bimonthly journal "Criticón" in 1970 that became a focal point for conservative and right-wing intellectuals in the Federal Republic of Germany. In 2000, he established the Foundation for Conservative Education and Research (FKBF) in Munich to preserve his private library of around 20,000 books. Since 2007, Dieter Stein, the editor of weekly newspaper Junge Freiheit, is the chairman of the foundation. In 2012, the library opened to the public in


id: german-national-library-of-science-and-technology-20260505-0
file: data/en.wikipedia.org/wiki/German_National_Library_of_Science_and_Technology-0.md
category: reference
title: German National Library of Science and Technology
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/German_National_Library_of_Science_and_Technology
date_saved: 2026-05-05T09:31:27.590220+00:00
instance: kb-cron
parent: german-national-library-of-science-and-technology-20260505-0
summary:
The German National Library of Science and Technology (German: Technische Informationsbibliothek), abbreviated TIB, is the national library of the Federal Republic of Germany for all fields of engineering, technology, and the natural sciences. It is jointly funded by the Federal Ministry of Education and Research (BMBF) and the 16 German states. Founded in 1959, the library operates in conjunction with the Leibniz Universität Hannover. In addition to acquiring scientific literature, it conducts applied research in such areas as the archiving of non-textual materials, data visualization and the future Internet. The library is also involved in a number of open access initiatives. With a collection of about 8.9 million items in 2012, the TIB is the largest technology and natural science library in the world. == Collection == The TIB acquires literature in all engineering fields as well as architecture, information technology, chemistry, mathematics, physics and other basic sciences. It is a particular specialist in the acquisition of "gray literature"; that is, literature difficult to obtain and not available via the standard book or journal trade. It also holds a large number of standards, norms, patents, source data, scientific conference proceedings, government research papers and dissertations. Special collections include the "Albrecht


id: german-national-library-of-science-and-technology-20260505-1
file: data/en.wikipedia.org/wiki/German_National_Library_of_Science_and_Technology-1.md
category: reference
title: German National Library of Science and Technology
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/German_National_Library_of_Science_and_Technology
date_saved: 2026-05-05T09:31:27.590220+00:00
instance: kb-cron
parent: german-national-library-of-science-and-technology-20260505-0
summary:
== Research projects == As part of the German national research infrastructure, the TIB conducts its own applied research, particularly in the field of information science. In cooperation with a variety of other institutions, these projects focus on the areas of visual searching, data visualization, the Semantic Web, and the Future Internet. === PROBADO 3D === PROBADO is a project to develop tools for the automatic indexing, storage and delivery of non-textual documents such as 3D models. Its goal is to enable academic libraries to deal with multimedia objects just as easily as with textual information. Tools include searching by intuitive drawing in 2D and 3D and delivery of results while drawing. For this initiative the TIB partnered with the Technical University of Darmstadt, the University of Bonn and the Technical University of Graz. === Visual access to research data === This project, funded by the Leibniz Association, is a joint effort of the TIB, the GRIS Darmstadt (Interactive Graphics Systems at the Technical University of Darmstadt) and the IGD (Fraunhofer Institute for Computer Graphics). It deals with developing approaches to the interactive, graphical access to research data in order to make it easily represented and searchable. The project is


id: gerstein-science-information-centre-20260505-0
file: data/en.wikipedia.org/wiki/Gerstein_Science_Information_Centre-0.md
category: reference
title: Gerstein Science Information Centre
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Gerstein_Science_Information_Centre
date_saved: 2026-05-05T09:31:28.812586+00:00
instance: kb-cron
parent: gerstein-science-information-centre-20260505-0
summary:
The Gerstein Science Information Centre is the University of Toronto's flagship library supporting the sciences and health sciences. The largest science and health science academic library in Canada, Gerstein has a collection of over 945,000 print volumes of journals and books, and also provides access to over 100,000 online journals and books. It is located in the Sigmund Samuel Library Building on the St. George campus in downtown Toronto, Ontario, Canada. The Gerstein Science Information Centre's collection consists primarily of material on the sciences, including the health sciences, medicine, physics, chemistry, biology and their subfields, with the exception of mathematical journals and forestry, botany and geology materials. The library provides varying degrees of access to students, faculty, external researchers, and members of the public. == History == The library originally existed as the main University of Toronto library, and maintained this status from 1892 to 1973. In 1973 the humanities and social sciences materials were moved to the then newly built Robarts Library, and the remaining collection was divided between the undergraduate Sigmund Samuel Library and the Science and Medicine Library. In 1997, the Science and Medicine Library was renamed the Gerstein Science Information Centre after a significant donation from


id: national-research-council-canada-national-science-library-20260505-0
file: data/en.wikipedia.org/wiki/National_Research_Council_Canada_National_Science_Library-0.md
category: reference
title: National Research Council Canada National Science Library
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/National_Research_Council_Canada_National_Science_Library
date_saved: 2026-05-05T09:31:29.974732+00:00
instance: kb-cron
parent: national-research-council-canada-national-science-library-20260505-0
summary:
The National Science Library (NSL), formerly known as the Canada Institute for Scientific and Technical Information or CISTI, began in 1917 as the library of the National Research Council of Canada (NRC). NRC is the Government of Canada's premier research and technology organization (RTO), working with clients and partners to provide innovation support, strategic research, scientific and technical services. The library took on the role of national science library unofficially in 1957 and became the official National Science Library in 1966. The National Science Library is located in Ottawa, Ontario, and houses one of the world's most comprehensive collections of publications in science, technology, engineering and medicine. It is part of NRC's Knowledge, Information and Technology Services Branch and provides NRC and Canada's research community with information and information services to accelerate discovery, innovation and commercialization. The NRC Research Press joined the library in 1992. On September 1, 2010, NRC Research Press became a private company called Canadian Science Publishing and is no longer directly affiliated with CISTI or the NRC. == Partnership initiatives == Shared library services – The NSL works with other Government of Canada science-based departments on a number of collaborative initiatives to realize common goals and


id: national-science-library-bangladesh-20260505-0
file: data/en.wikipedia.org/wiki/National_Science_Library_(Bangladesh)-0.md
category: reference
title: National Science Library (Bangladesh)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/National_Science_Library_(Bangladesh)
date_saved: 2026-05-05T09:31:31.131492+00:00
instance: kb-cron
parent: national-science-library-bangladesh-20260505-0
summary:
The National Science Library is a state owned and supported science library of Bangladesh. == History == The National Science Library was established in 1981 under the Bangladesh National Scientific and Technical Documentation Centre. Its functions are to collect scientific publications and books. == References ==


id: national-science-library-georgia-20260505-0
file: data/en.wikipedia.org/wiki/National_Science_Library_(Georgia)-0.md
category: reference
title: National Science Library (Georgia)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/National_Science_Library_(Georgia)
date_saved: 2026-05-05T09:31:32.299075+00:00
instance: kb-cron
parent: national-science-library-georgia-20260505-0
summary:
The National Scientific Library (Georgian: ეროვნული სამეცნიერო ბიბლიოთეკა) is a library in Tbilisi, Georgia. National Scientific Library is a biggest library in Georgia. Established in 1941, it initially served only the employees of the Georgian National Academy of Sciences. Presently library has three buildings: founded in 1941 former Central Library of Georgian Academy of Sciences, founded in 1965 Science and Technology Library and founded in 1961 Library-Museum of Ioseb Grishashvili. == See also == List of libraries in Georgia (country) == References ==


id: radcliffe-science-library-20260505-0
file: data/en.wikipedia.org/wiki/Radcliffe_Science_Library-0.md
category: reference
title: Radcliffe Science Library
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Radcliffe_Science_Library
date_saved: 2026-05-05T09:31:34.566727+00:00
instance: kb-cron
parent: radcliffe-science-library-20260505-0
summary:
The Radcliffe Science Library (RSL) is the main teaching and research science library at the University of Oxford in Oxford, England. Being officially part of the Bodleian Libraries, the library holds the Legal Deposit material for the sciences and is thus entitled to receive a copy of all British scientific publications. Since 2023 the library has shared its buildings with Reuben College. == History == The physician John Radcliffe died in 1714, leaving money in his will to establish the Radcliffe Observatory, the Radcliffe Infirmary and the Radcliffe Library, which was intended to contain "modern books in all faculties and languages, not in the Bodleian Library". The library's building on a site south of the Bodleian Library was completed in 1749 and is now known as the Radcliffe Camera. The scientific books housed in the Radcliffe Camera were transferred to the Oxford University Museum of Natural History in 1861. A new Radcliffe Library building opened in 1901, on land next to the museum (on the corner of Parks Road and South Parks Road). In 1927, the library lost its independence, for financial efficiency becoming part of the Bodleian Library. The library took on its current name, the Radcliffe Science Library,


id: regional-planetary-image-facility-20260505-0
file: data/en.wikipedia.org/wiki/Regional_Planetary_Image_Facility-0.md
category: reference
title: Regional Planetary Image Facility
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Regional_Planetary_Image_Facility
date_saved: 2026-05-05T09:31:35.677978+00:00
instance: kb-cron
parent: regional-planetary-image-facility-20260505-0
summary:
The Regional Planetary Image Facilities (RPIFs) are planetary image and data libraries located throughout the United States and abroad that are funded by the host institutions. They once had funding from NASA. A network of these facilities was established in 1977 to maintain photographic and digital data as well as mission documentation. Each facility's general holding contains images and maps of planets and their satellites taken by solar system exploration spacecraft. These planetary image facilities are often open to the public. The facilities are primarily reference centers for browsing, studying, and selecting lunar and planetary photographic and cartographic materials. Experienced staff can assist scientists, educators, students, media, and the public in ordering materials for their own use. Since it was formally established, the network of RPIFs once numbered nine U.S. facilities and seven in other countries. The first RPIF to be established outside of the U.S. was in England in 1980 at the University College London (UCL), and since then RPIFs have been set up in Canada, France, Germany, Israel, Italy, and Japan. == Resources and services offered == The RPIFs store and maintain a variety of planetary data and imagery, making them unique resources covering decades of planetary science.


id: russian-national-public-library-for-science-and-technology-20260505-0
file: data/en.wikipedia.org/wiki/Russian_National_Public_Library_for_Science_and_Technology-0.md
category: reference
title: Russian National Public Library for Science and Technology
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Russian_National_Public_Library_for_Science_and_Technology
date_saved: 2026-05-05T09:31:36.875920+00:00
instance: kb-cron
parent: russian-national-public-library-for-science-and-technology-20260505-0
summary:
The Russian National Public Library for Science and Technology (Russian: Государственная Публичная Научно-Техническая Библиотека России, romanized: Gosudarstvennaya Publichnaya Nauchno-Tekhnicheskaya Biblioteka Rossii), abbreviated GPNTB (Russian: ГПНТБ) is a national library for engineering, science, and technology in Moscow, Russia. It was founded in 1958 on the basis of the State Science Library of the Ministry of Higher Education of the Soviet Union. It is located in Khoroshyovsky district of Moscow. The mission of the library is to collect and store national and foreign science and technical literature, then disseminate information and bibliographical services for commercial, organisations and other institutions of the Russian Federation, development and application of up-to-date automated information technologies. == See also == List of libraries in Russia == References == == External links == Official website


id: slavonic-library-in-prague-20260505-0
file: data/en.wikipedia.org/wiki/Slavonic_Library_in_Prague-0.md
category: reference
title: Slavonic Library in Prague
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Slavonic_Library_in_Prague
date_saved: 2026-05-05T09:31:38.078618+00:00
instance: kb-cron
parent: slavonic-library-in-prague-20260505-0
summary:
The Slavonic Library (Czech: Slovanská knihovna) in Prague is a publicly accessible specialised research library for the field of Slavic Studies. It is one of the largest and most important Slavic libraries in Europe. Since its foundation in 1924, it has been systematically complementing, processing and making accessible its collection of world research Slavic (mainly historical, philological and political-science) literature and selected original production of Slavic authors. Its depositories contain more than 850,000 volumes of library documents, a collection of maps, posters, visual and artistic materials, and numerous collections of special documents. The Slavonic Library provides library and information services concerning the political, economic and cultural life of the Slavic nations, their mutual relations and their relations to other nations in the past as well as the present. Documents can be studied in the library's public reading room, provided with free internet access, an extensive reference library and open-access shelving with a large number of volumes. The library processes and edits specialised bibliographies and publications in its field. It organizes cultural events, professional seminars, conferences and exhibitions. Following the decision of the International Committee of Slavists, it has fulfilled the function of the centre for recording and processing materials related


id: slavonic-library-in-prague-20260505-1
file: data/en.wikipedia.org/wiki/Slavonic_Library_in_Prague-1.md
category: reference
title: Slavonic Library in Prague
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Slavonic_Library_in_Prague
date_saved: 2026-05-05T09:31:38.078618+00:00
instance: kb-cron
parent: slavonic-library-in-prague-20260505-0
summary:
== The Book Collection == The book collection of the Slavonic Library comprises more than 850,000 library units (as of June 2018). On average, it is augmented by 9,000 new volumes of books and several hundred titles of periodicals every year. It is a varied collection of Slavic Studies literature, complexly mapping the historical, literary, philological and cultural topics of all Slavic nations. The core of individual national sections is formed by personal libraries acquired through donation or purchase in the first decades of the library's existence. Since the early 1930s, the acquisitions were carried out systematically according to a thematic plan of acquisition. The Slavonic Library owns several hundred historical manuscript books and several thousand early printed books published before 1800, but most of the collection is formed by the production of the 19th‒21st centuries. The holdings are complemented by a number of collections of special non-library documents. Almost all catalogue records of books and periodicals are available in the electronic catalogue of the Slavonic Library. Likewise the scanned general card catalogue of the Slavonic Library, used until 1996, and the scanned card catalogue of the Russian Historical Archives Abroad from 1923 to 1945 are accessible. The inventory lists


id: slavonic-library-in-prague-20260505-2
file: data/en.wikipedia.org/wiki/Slavonic_Library_in_Prague-2.md
category: reference
title: Slavonic Library in Prague
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Slavonic_Library_in_Prague
date_saved: 2026-05-05T09:31:38.078618+00:00
instance: kb-cron
parent: slavonic-library-in-prague-20260505-0
summary:
=== Collections of Special Documents === A valuable part of the holdings is the section of special collections containing documents of non-library character. Many of them are related to the topic of Russian and Ukrainian emigration of the interwar period: these are parts of the personal estates of the Russian émigrés Petr N. Savitskii, Antonii V. Florovskii, Alfred L. Bem and Vladimir N. Tukalevskii; the collection of the administrative documents of the Russian Historical Archives Abroad; and the collection of leaflets and invitations to cultural and social events of Russian and Ukrainian émigrés related to the activities of diverse Ukrainian organisations functioning in interwar Czechoslovakia. Another unique collection is the set of more than a thousand hand-painted posters and leaflets made by Ukrainian émigrés in former Czechoslovakia between 1918 and 1945. Other interesting documents include the correspondence of the Lusatian cultural figure Michał Hórnik, the protoiereus Nikolai N. Ryzhkov, the Ukrainian poet Lesia Ukrainka, the documents of the Leningrad artist Vadim M. Rokhlin, and the archive of clippings of articles about Yugoslavia from Czech periodicals in 1934‒1939. The items preserved in fragments include the correspondence of famous writers (P. I. Chaadaev, L. N. Tolstoi, F. M. Dostojevskii, A. M. Remizov


id: slavonic-library-in-prague-20260505-3
file: data/en.wikipedia.org/wiki/Slavonic_Library_in_Prague-3.md
category: reference
title: Slavonic Library in Prague
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Slavonic_Library_in_Prague
date_saved: 2026-05-05T09:31:38.078618+00:00
instance: kb-cron
parent: slavonic-library-in-prague-20260505-0
summary:
== Literature == Rachůnková, Zdeňka (2002). The Slavonic Library. Prague: National Library of the Czech Republic. pp. 3-28. ISBN 8070503947. Vacek, Jiří (2016). Slovanská knihovna - můj osud. Prague: National Library of the Czech Republic. ISBN 9788070506714. 2Strnadel, Jiří (1976). Padesát let Slovanské knihovny v Praze. Prague: Státní knihovna ČSR - Slovanská knihovna. pp. 73–122.. Řeháková, Michaela; Babka, Lukáš (2005). Soupis publikací vydaných Slovanskou knihovnou )1924 - 2004) [The List of Publications Issued by the Slavonic Library (1924–2004). Published on the Occasion of the 80th Anniversary of the Activities of the Slavonic Library]. Prague: National Library of the Czech Republic - Slavonic Library. ISBN 8070504595.M Vacek, Jiří; Babka, Lukáš (2009). Voices of the Banished. Periodical Press of the Emigration from Soviet Russia (1918–1945). Prague: National Library of the Czech Republic. ISBN 978-80-7050-559-5. Richard J. Kneeley – Edward Kasinec; The Slovanská knihovna in Prague and its RZIA Collection, Slavic Review 51 (1992), no. 1, pp. 122–130. == External links == The Slavonic Library website The electronic catalogue of the Slavonic Library The card catalogue of the Slavonic Library The card catalogue of the books from the Russian Historical Archives Abroad Special collections of the Slavonic Library New Acquisitions of Slavic Studies


id: state-scientific-and-technical-library-of-ukraine-20260505-0
file: data/en.wikipedia.org/wiki/State_Scientific_and_Technical_Library_of_Ukraine-0.md
category: reference
title: State Scientific and Technical Library of Ukraine
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/State_Scientific_and_Technical_Library_of_Ukraine
date_saved: 2026-05-05T09:31:53.224573+00:00
instance: kb-cron
parent: state-scientific-and-technical-library-of-ukraine-20260505-0
summary:
The State Scientific and Technical Library of Ukraine, SSTL (Ukrainian: Державна науково-технічна бібліотека України) is the main academic library of Ukraine and is part of the system of scientific and technical information of the Ministry of Education and Science of Ukraine. The purpose of the State Scientific and Technical Library of Ukraine activity is to promote the implementation of state policy in the field of education, science and culture, and to ensure the access of scientists, specialists, and citizens to sources of scientific and technical information. == History == In March 1935, the Interbranch Technical Library of the USSR was created that was the branch of the State Scientific Library (SSL) of the People's Commissariat of Heavy Industry (Narkomtiofjazhprom) of the USSR. In 1936, the Kyiv Branch of the National Library of Ukraine made 5 thousand copies of publications and served 20 thousand readers. During World War II, almost all the fund and the library building itself were destroyed. The restoration of the library began in late 1946. Until 1958, the name and subordination of the library changed several times. The renewed funds as of January 1, 1959, amounted to more than 200,000 units. The library was granted the status


id: stefanyk-national-scientific-library-20260505-0
file: data/en.wikipedia.org/wiki/Stefanyk_National_Scientific_Library-0.md
category: reference
title: Stefanyk National Scientific Library
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Stefanyk_National_Scientific_Library
date_saved: 2026-05-05T09:31:54.370804+00:00
instance: kb-cron
parent: stefanyk-national-scientific-library-20260505-0
summary:
National Scientific Library (Ukrainian: Львівська національна наукова бібліотека України імені Василя Стефаника, romanized: Lvivska natsionalna naukova biblioteka Ukrainy imeni Vasylia Stefanyka) is a national library of Ukraine in the city of Lviv, Ukraine. It also serves as a science and research institute complex of the National Academy of Sciences of Ukraine. The library formally was established on 2 January 1940 with its headquarters in the building of Ossolineum and composed of holdings of Ossolineum and many other major libraries and private collections, all nationalized after the territory was annexed by the Soviet Union as a result of its invasion of Poland. It was named after Vasyl Stefanyk in 1971. To the development of the library greatly contributed Ukrainian archaeologist Larysa Krushelnytska who was appointed as its head in October 1991. == See also == Ossolineum List of libraries in Ukraine == References == == External links == Stefanyk National Scientific Library website


id: sukkulenten-sammlung-zurich-20260505-0
file: data/en.wikipedia.org/wiki/Sukkulenten-Sammlung_Zurich-0.md
category: reference
title: Sukkulenten-Sammlung Zurich
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Sukkulenten-Sammlung_Zurich
date_saved: 2026-05-05T09:31:55.574288+00:00
instance: kb-cron
parent: sukkulenten-sammlung-zurich-20260505-0
summary:
Sukkulenten-Sammlung Zürich, literally succulent plant collection of the city of Zürich, is a botanical garden in the Swiss municipality of Zürich. It also houses a botanic library, a herbarium and the International Organizations for Succulent Plant Research (IOS). == Location == The greenhouses are located in district of Enge, on Zürichsee (Lake Zurich). They are a part of the Quaianlagen promenades, and are located on the southwestern lake shore. The collection is separated by the Mythenquai road from the lower lake shore promenade and the Enge harbour area, at the park facilities of the Mythenquai lido near the lower entrance to the Rieterpark. == History == At the end of the 1920s, Jakob Gasser, a cactus grower from Zürich, tried to sell his collection of about 1,500 succulents to the city government of Zürich, but the venture failed. in 1929, Julius Brann Gassersche, a store owner, acquired the unique collection and made a gift of it to the city of Zürich. The collection was housed in the greenhouses at the former site of the municipal gardens (Stadtgärtnerei) at Mythenquai, and established as Städtische Kakteensammlung, meaning urban cactus collection. Formally established in 1931, the collection houses one of the largest and


id: history-of-measurement-20260505-0
file: data/en.wikipedia.org/wiki/History_of_measurement-0.md
category: reference
title: History of measurement
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_measurement
date_saved: 2026-05-05T09:31:57.161665+00:00
instance: kb-cron
parent: history-of-measurement-20260505-0
summary:
The earliest recorded systems of weights and measures originate in the 3rd or 4th millennium BC. == History of units == === Units of length === Before the establishment of the decimal metric system in France during the French Revolution in the late 18th century, many units of length were based on parts of the human body. The Nippur cubit was one of the oldest known units of length. The oldest known metal standard for length corresponds to this Sumerian unit and dates from 2650 BCE. This copper bar was discovered in Nippur, on the banks of the Euphrates, and is kept in the Istanbul Archaeological Museum. Archaeologists consider that this 51.85 centimetres long unit was the origin of the Roman foot. Indeed, the Egyptians divided the Sumerian cubit into 28 fingers and 16 of these fingers gave a Roman foot of 29.633 cm. === Units of mass === The grain was the earliest unit of mass and is the smallest unit in the apothecary, avoirdupois, Tower, and troy systems. The early unit was a grain of wheat or barleycorn used to weigh the precious metals silver and gold. Larger units preserved in stone standards were developed that were used


id: history-of-measurement-20260505-1
file: data/en.wikipedia.org/wiki/History_of_measurement-1.md
category: reference
title: History of measurement
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_measurement
date_saved: 2026-05-05T09:31:57.161665+00:00
instance: kb-cron
parent: history-of-measurement-20260505-0
summary:
The metric system was first described in 1668 and officially adopted by France in 1799. Over the 19th and 20th centuries, it became the dominant system worldwide, although several countries, including the United States, China, and the United Kingdom continue to use their customary units, such as the mile. Among the numerous customary systems, many have been adapted to become an integer multiple of a related metric unit: The Scandinavian mile is now defined as 10 km, the Chinese jin is now defined as 0.5 kg, and the Dutch ons is now defined as 100 g. == See also == Historical metrology Metrication == References == This article incorporates public domain material from Specifications, Tolerances, and Other Technical Requirements for Weighing (Handbook 44 -2018). National Institute of Standards and Technology. == Further reading == , Measures and Weights in the Islamic World. An English Translation of Professor Walther Hinz's Handbook “Islamische Maße und Gewichte“, with a foreword by Professor Bosworth, F.B.A. Kuala Lumpur, ISTAC, 2002, ISBN 983-9379-27-5. This work is an annotated translation of a work in German by the late German orientalist Walther Hinz, published in the Handbuch der Orientalistik, erste Abteilung, Ergänzungsband I, Heft 1, Leiden, The Netherlands:


id: anthropic-units-20260505-0
file: data/en.wikipedia.org/wiki/Anthropic_units-0.md
category: reference
title: Anthropic units
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Anthropic_units
date_saved: 2026-05-05T09:31:59.511854+00:00
instance: kb-cron
parent: anthropic-units-20260505-0
summary:
The term anthropic unit (from Greek άνθρωπος, 'human') is used with different meanings in archaeology, in measurement and in social studies. == In archaeology == In archaeology, anthropic units are strata or deposits of material containing a high proportion of man-made detritus. For example: "… 'degraded anthropic units', i.e., deposits produced by weathering and decay of fired bricks and mixed fill with non-selected inclusions …" == In measurement == Following the coinage of the term "anthropic principle" by Brandon Carter in 1973–1974, units of measurement that are on a human scale are occasionally referred to as "anthropic units", as the example here: "… the metre and kilogram occupy a reasonably central position as far as symmetry in positive and negative powers of ten is concerned, emphasising that the SI units are natural anthropic units …" == In social studies == In fields of study such as sociology and ethnography, anthropic units are identifiable groupings of people. For example: "Ethnographers have been accustomed to deal with the 'race', the 'tribe' and the 'nation' as social or anthropic units …" and: "... among the more primitive anthropic units it seems a grave ineptitude for the Chukchees not to adopt the snowhouse building


id: history-of-anthropometry-20260505-0
file: data/en.wikipedia.org/wiki/History_of_anthropometry-0.md
category: reference
title: History of anthropometry
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_anthropometry
date_saved: 2026-05-05T09:32:00.752465+00:00
instance: kb-cron
parent: history-of-anthropometry-20260505-0
summary:
The history of anthropometry includes its use as an early tool of anthropology, use for identification, use for the purposes of understanding human physical variation in paleoanthropology and in various attempts to correlate physical with racial and psychological traits. At various points in history, certain anthropometrics have been cited by advocates of discrimination and eugenics often as a part of some social movement or through pseudoscientific claims. == Craniometry and paleoanthropology == In 1716 Louis-Jean-Marie Daubenton, who wrote many essays on comparative anatomy for the Académie française, published his Memoir on the Different Positions of the Occipital Foramen in Man and Animals (Mémoire sur les différences de la situation du grand trou occipital dans l'homme et dans les animaux). Six years later Pieter Camper (1722–1789), distinguished both as an artist and as an anatomist, published some lectures that laid the foundation of much work. Camper invented the "facial angle," a measure meant to determine intelligence among various species. According to this technique, a "facial angle" was formed by drawing two lines: one horizontally from the nostril to the ear; and the other perpendicularly from the advancing part of the upper jawbone to the most prominent part of the forehead. Camper's


id: history-of-anthropometry-20260505-1
file: data/en.wikipedia.org/wiki/History_of_anthropometry-1.md
category: reference
title: History of anthropometry
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_anthropometry
date_saved: 2026-05-05T09:32:00.752465+00:00
instance: kb-cron
parent: history-of-anthropometry-20260505-0
summary:
In 1883, Frenchman Alphonse Bertillon introduced a system of identification that was named after him. The "Bertillonage" system was based on the finding that several measures of physical features, such as the dimensions of bony structures in the body, remain fairly constant throughout adult life. Bertillon concluded that when these measurements were made and recorded systematically, every individual would be distinguishable. Bertillon's goal was a way of identifying recidivists ("repeat offenders"). Previously police could only record general descriptions. Photography of criminals had become commonplace, but there was no easy way to sort the many thousands of photographs except by name. Bertillon's hope was that, through the use of measurements, a set of identifying numbers could be entered into a filing system installed in a single cabinet. The system involved 10 measurements; height, stretch (distance from left shoulder to middle finger of raised right arm), bust (torso from head to seat when seated), head length (crown to forehead) and head width temple to temple) width of cheeks, and "lengths" of the right ear, the left foot, middle finger, and cubit (elbow to tip of middle finger). It was possible, by exhaustion, to sort the cards on which these details were recorded


id: history-of-anthropometry-20260505-2
file: data/en.wikipedia.org/wiki/History_of_anthropometry-2.md
category: reference
title: History of anthropometry
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_anthropometry
date_saved: 2026-05-05T09:32:00.752465+00:00
instance: kb-cron
parent: history-of-anthropometry-20260505-0
summary:
Phylogeography is the science of identifying and tracking major human migrations, especially in prehistoric times. Linguistics can follow the movement of languages and archaeology can follow the movement of artefact styles but neither can tell whether a culture's spread was due to a source population's physically migrating or to a destination population's simply copying the technology and learning the language. Anthropometry was used extensively by anthropologists studying human and racial origins: some attempted racial differentiation and classification, often seeking ways in which certain races were inferior to others. Nott translated Arthur de Gobineau's An Essay on the Inequality of the Human Races (1853–1855), a founding work of racial segregationism that made three main divisions between races, based not on colour but on climatic conditions and geographic location, and privileged the "Aryan" race. Science has tested many theories aligning race and personality, which have been current since Boulainvilliers (1658–1722) contrasted the Français (French people), alleged descendants of the Nordic Franks, and members of the aristocracy, to the Third Estate, considered to be indigenous Gallo-Roman people subordinated by right of conquest. François Bernier, Carl Linnaeus and Blumenbach had examined multiple observable human characteristics in search of a typology. Bernier based his racial


id: history-of-anthropometry-20260505-3
file: data/en.wikipedia.org/wiki/History_of_anthropometry-3.md
category: reference
title: History of anthropometry
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_anthropometry
date_saved: 2026-05-05T09:32:00.752465+00:00
instance: kb-cron
parent: history-of-anthropometry-20260505-0
summary:
In Crania Americana Morton claimed that Caucasians had the biggest brains, averaging 87 cubic inches, Indians were in the middle with an average of 82 cubic inches and Negroes had the smallest brains with an average of 78 cubic inches. In 1873 Paul Broca (1824–1880) found the same pattern described by Samuel Morton's Crania Americana by weighing brains at autopsy. Other historical studies alleging a Black–White difference in brain size include Bean (1906), Mall, (1909), Pearl, (1934) and Vint (1934). But in Germany Rudolf Virchow's study led him to denounce "Nordic mysticism" in the 1885 Anthropology Congress in Karlsruhe. Josef Kollmann, a collaborator of Virchow, stated in the same congress that the people of Europe, be them German, Italian, English or French, belonged to a "mixture of various races," furthermore declaring that the "results of craniology" led to "struggle against any theory concerning the superiority of this or that European race". Virchow later rejected measure of skulls as legitimate means of taxonomy. Paul Kretschmer quoted an 1892 discussion with him concerning these criticisms, also citing Aurel von Törok's 1895 work, who basically proclaimed the failure of craniometry. Stephen Jay Gould (1941–2002) claimed Samuel Morton had fudged data and "overpacked" the


id: history-of-anthropometry-20260505-4
file: data/en.wikipedia.org/wiki/History_of_anthropometry-4.md
category: reference
title: History of anthropometry
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_anthropometry
date_saved: 2026-05-05T09:32:00.752465+00:00
instance: kb-cron
parent: history-of-anthropometry-20260505-0
summary:
Caucasoid characterized by a tall dolichocephalic skull, receded zygomas, large brow ridge and projecting-narrow nasal apertures. Negroid characterized by a short dolichocephalic skull, receded zygomas and wide nasal apertures. Mongoloid characterized by a medium brachycephalic skull, projecting zygomas, small brow ridge and small nasal apertures. Ripley's The Races of Europe was rewritten in 1939 by Harvard physical anthropologist Carleton S. Coon. Coon, a 20th-century craniofacial anthropometrist, used the technique for his The Origin of Races (New York: Knopf, 1962). Because of the inconsistencies in the old three-part system (Caucasoid, Mongoloid, Negroid), Coon adopted a five-part scheme. He defined "Caucasoid" as a pattern of skull measurements and other phenotypical characteristics typical of populations in Europe, Central Asia, South Asia, West Asia, North Africa, and Northeast Africa (Ethiopia, and Somalia). He discarded the term "Negroid" as misleading since it implies skin tone, which is found at low latitudes around the globe and is a product of adaptation, and defined skulls typical of sub-Saharan Africa as "Congoid" and those of Southern Africa as "Capoid". Finally, he split "Australoid" from "Mongoloid" along a line roughly similar to the modern distinction between sinodonts in the north and sundadonts in the south. He argued that these


id: bedford-level-experiment-20260505-0
file: data/en.wikipedia.org/wiki/Bedford_Level_experiment-0.md
category: reference
title: Bedford Level experiment
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Bedford_Level_experiment
date_saved: 2026-05-05T09:32:01.898253+00:00
instance: kb-cron
parent: bedford-level-experiment-20260505-0
summary:
The Bedford Level experiment was a series of observations carried out along a 6-mile (10 km) length of the Old Bedford River on the Bedford Level of the Cambridgeshire Fens in the United Kingdom. They were performed during the 19th and early 20th centuries to deny the curvature of the Earth through measurement. Samuel Birley Rowbotham, who conducted the first observations starting in 1838, claimed that he had proven the Earth to be flat. However, in 1870, after adjusting Rowbotham's method to allow for the effects of atmospheric refraction, Alfred Russel Wallace found a curvature consistent with a spherical Earth. == The Bedford Level == At the point chosen for all the experiments, the river is a slow-flowing drainage canal running in an uninterrupted straight line for a 6-mile (10 km) stretch to the north-east of the village of Welney. This makes it an ideal location to directly measure the curvature of the Earth, as Rowbotham wrote in Zetetic Astronomy: If the earth is a globe, and is 25,000 English statute miles in circumference, the surface of all standing water must have a certain degree of convexity—every part must be an arc of a circle. From the summit of any


id: bedford-level-experiment-20260505-1
file: data/en.wikipedia.org/wiki/Bedford_Level_experiment-1.md
category: reference
title: Bedford Level experiment
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Bedford_Level_experiment
date_saved: 2026-05-05T09:32:01.898253+00:00
instance: kb-cron
parent: bedford-level-experiment-20260505-0
summary:
On 11 May 1904 Lady Elizabeth Anne Blount, who was later influential in the formation of the Flat Earth Society, hired a commercial photographer to use a telephoto-lens camera to take a picture from Welney of a large white sheet she had placed, the bottom edge near the surface of the river, at Rowbotham's original position 6 miles (10 km) away. The photographer, Edgar Clifton from Dallmeyer's studio, mounted his camera 2 feet (0.6 m) above the water at Welney and was surprised to be able to obtain a picture of the target, which he believed should have been invisible to him, given the low mounting point of the camera. Lady Blount published the pictures far and wide. These controversies became a regular feature in the English Mechanic magazine in 1904–05, which published Blount's photo and reported two experiments in 1905 that showed the opposite results. One of these, by Clement Stretton conducted on the Ashby Canal, mounted a theodolite on the canal bank aligned with the cabin roof of a boat. When the boat had moved one mile distant, the instrument showed a dip from the sight-line of about eight inches. == Refraction == Atmospheric refraction can produce the


id: history-of-geodesy-20260505-0
file: data/en.wikipedia.org/wiki/History_of_geodesy-0.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
The history of geodesy (/dʒiːˈɒdɪsi/) began during antiquity and ultimately blossomed during the Age of Enlightenment. Many early conceptions of the Earth held it to be flat, with the heavens being a physical dome spanning over it. Early arguments for a spherical Earth pointed to various more subtle empirical observations, including how lunar eclipses were seen as circular shadows, as well as the fact that Polaris is seen lower in the sky as one travels southward. == Hellenic world == === Initial developments === Though the earliest written mention of a spherical Earth comes from ancient Greek sources, there is no account of how the sphericity of Earth was discovered, or if it was initially simply a guess. A plausible explanation given by the historian Otto E. Neugebauer is that it was "the experience of travellers that suggested such an explanation for the variation in the observable altitude of the pole and the change in the area of circumpolar stars, a change that was quite drastic between Greek settlements" around the eastern Mediterranean Sea, particularly those between the Nile Delta and Crimea. Another possible explanation can be traced back to earlier Phoenician sailors. The first circumnavigation of Africa is described


id: history-of-geodesy-20260505-1
file: data/en.wikipedia.org/wiki/History_of_geodesy-1.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
Every portion of Earth tends toward the centre until by compression and convergence they form a sphere. Travelers going south see southern constellations rise higher above the horizon. The shadow of Earth on the Moon during a lunar eclipse is round. The concepts of symmetry, equilibrium and cyclic repetition permeated Aristotle's work. In his Meteorology he divided the world into five climatic zones: two temperate areas separated by a torrid zone near the equator, and two cold inhospitable regions, "one near our upper or northern pole and the other near the [...] southern pole", both impenetrable and girdled with ice. Although no humans could survive in the frigid zones, inhabitants in the southern temperate regions could exist. Aristotle's theory of natural place relied on a spherical Earth to explain why heavy things go down (toward what Aristotle believed was the center of the Universe), and things like air and fire go up. In this geocentric model, the structure of the universe was believed to be a series of perfect spheres. The Sun, Moon, planets and fixed stars were believed to move on celestial spheres around a stationary Earth. Though Aristotle's theory of physics survived in the Christian world for many


id: history-of-geodesy-20260505-2
file: data/en.wikipedia.org/wiki/History_of_geodesy-2.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
=== Posidonius === A parallel later ancient measurement of the size of the Earth was made by another Greek scholar, Posidonius (c. 135 – 51 BC), using a similar method as Eratosthenes. Instead of observing the Sun, he noted that the star Canopus was hidden from view in most parts of Greece but that it just grazed the horizon at Rhodes. Posidonius is supposed to have measured the angular elevation of Canopus at Alexandria and determined that the angle was 1/48 of a circle. He used a distance from Alexandria to Rhodes, 5000 stadia, and so he computed the Earth's circumference in stadia as 48 × 5000 = 240,000. Some scholars see these results as luckily semi-accurate due to cancellation of errors. But since the Canopus observations are both mistaken by over a degree, the "experiment" may be not much more than a recycling of Eratosthenes's numbers, while altering 1/50 to the correct 1/48 of a circle. Later, either he or a follower appears to have altered the base distance to agree with Eratosthenes's Alexandria-to-Rhodes figure of 3750 stadia, since Posidonius' final circumference was 180,000 stadia, which equals 48 × 3750 stadia. The 180,000 stadia circumference of Posidonius is close


id: history-of-geodesy-20260505-3
file: data/en.wikipedia.org/wiki/History_of_geodesy-3.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
=== Late Antiquity === Knowledge of the spherical shape of Earth was received in scholarship of Late Antiquity as a matter of course, in both Neoplatonism and Early Christianity. Calcidius's fourth-century Latin commentary on and translation of Plato's Timaeus, which was one of the few examples of Greek scientific thought that was known in the Early Middle Ages in Western Europe, discussed Hipparchus's use of the geometrical circumstances of eclipses in On Sizes and Distances to compute the relative diameters of the Sun, Earth, and Moon. Theological doubt informed by the flat Earth model implied in the Hebrew Bible inspired some early Christian scholars such as Lactantius, John Chrysostom and Athanasius of Alexandria, but this remained an eccentric current. Learned Christian authors such as Basil of Caesarea, Ambrose and Augustine of Hippo were clearly aware of the sphericity of Earth. "Flat Earthism" lingered longest in Syriac Christianity, which tradition laid greater importance on a literalist interpretation of the Old Testament. Authors from that tradition, such as Cosmas Indicopleustes, presented Earth as flat as late as in the 6th century. This last remnant of the ancient model of the cosmos disappeared during the 7th century. From the 8th century and the


id: history-of-geodesy-20260505-4
file: data/en.wikipedia.org/wiki/History_of_geodesy-4.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
=== Al-Farghānī === Al-Farghānī (Latinized as Alfraganus) was a Persian astronomer of the 9th century involved in measuring the diameter of Earth, and commissioned by Al-Ma'mun. His estimate given above for a degree (562⁄3 Arabic miles) was much more accurate than the 602⁄3 Roman miles (89.7 km) given by Ptolemy. Christopher Columbus uncritically used Alfraganus's figure as if it were in Roman miles instead of in Arabic miles, in order to prove a smaller size of Earth than that propounded by Ptolemy. === Al-Biruni === Abu Rayhan Biruni (973–1048), in contrast to his predecessors, who measured Earth's circumference by sighting the Sun simultaneously from two different locations, developed a new method of using trigonometric calculations based on the angle between a plain and mountain top. This yielded more accurate measurements of Earth's circumference and made it possible for a single person to measure it from a single location. Biruni's method was intended to avoid "walking across hot, dusty deserts", and the idea came to him when he was on top of a tall mountain in India (present day Pind Dadan Khan, Pakistan). From the top of the mountain, he sighted the dip angle which, along with the mountain's height (which


id: history-of-geodesy-20260505-5
file: data/en.wikipedia.org/wiki/History_of_geodesy-5.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
==== Bede the Venerable ==== The monk Bede (c. 672–735) wrote in his influential treatise on computus, The Reckoning of Time, that Earth was round. He explained the unequal length of daylight from "the roundness of the Earth, for not without reason is it called 'the orb of the world' on the pages of Holy Scripture and of ordinary literature. It is, in fact, set like a sphere in the middle of the whole universe." The large number of surviving manuscripts of The Reckoning of Time, copied to meet the Carolingian requirement that all priests should study the computus, indicates that many, if not most, priests were exposed to the idea of the sphericity of Earth. Ælfric of Eynsham paraphrased Bede into Old English, saying, "Now the Earth's roundness and the Sun's orbit constitute the obstacle to the day's being equally long in every land." Bede was lucid about Earth's sphericity, writing "We call the earth a globe, not as if the shape of a sphere were expressed in the diversity of plains and mountains, but because, if all things are included in the outline, the earth's circumference will represent the figure of a perfect globe ... For truly it


id: history-of-geodesy-20260505-6
file: data/en.wikipedia.org/wiki/History_of_geodesy-6.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
European astronomy was so much judged worth consideration that numerous Chinese authors developed the idea that the Chinese of antiquity had anticipated most of the novelties presented by the missionaries as European discoveries, for example, the rotundity of the Earth and the "heavenly spherical star carrier model". Making skillful use of philology, these authors cleverly reinterpreted the greatest technical and literary works of Chinese antiquity. From this sprang a new science wholly dedicated to the demonstration of the Chinese origin of astronomy and more generally of all European science and technology. Although mainstream Chinese science until the 17th century held the view that Earth was flat, square, and enveloped by the celestial sphere, this idea was criticized by the Jin-dynasty scholar Yu Xi (fl. 307–345), who suggested that Earth could be either square or round, in accordance with the shape of the heavens. The Yuan-dynasty mathematician Li Ye (c. 1192–1279) firmly argued that Earth was spherical, just like the shape of the heavens only smaller, since a square Earth would hinder the movement of the heavens and celestial bodies in his estimation. The 17th-century Ge zhi cao treatise also used the same terminology to describe the shape of Earth that


id: history-of-geodesy-20260505-7
file: data/en.wikipedia.org/wiki/History_of_geodesy-7.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
This result, if correct, meant that Earth was not a sphere, but a prolate spheroid (taller than wide). However, this contradicted computations by Isaac Newton and Christiaan Huygens. In 1659, Christiaan Huygens was the first to derive the now standard formula for the centrifugal force in his work De vi centrifuga. The formula played a central role in classical mechanics and became known as the second of Newton's laws of motion. Newton's theory of gravitation combined with the rotation of the Earth predicted the Earth to be an oblate spheroid (wider than tall), with a flattening of 1:230. The issue could be settled by measuring, for a number of points on Earth, the relationship between their distance (in north–south direction) and the angles between their zeniths. On an oblate Earth, the meridional distance corresponding to one degree of latitude will grow toward the poles, as can be demonstrated mathematically. The French Academy of Sciences dispatched two expeditions. One expedition (1736–37) under Pierre Louis Maupertuis was sent to Torne Valley (near the Earth's North Pole). The second mission (1735–1744) under Pierre Bouguer was sent to what is modern-day Ecuador, near the equator. Their measurements demonstrated an oblate Earth, with a flattening


id: history-of-geodesy-20260505-8
file: data/en.wikipedia.org/wiki/History_of_geodesy-8.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
The Scandinavian-Russian meridian arc or Struve Geodetic Arc, named after the German astronomer Friedrich Georg Wilhelm von Struve, was a degree measurement that consisted of a nearly 3000 km long network of geodetic survey points. The Struve Geodetic Arc was one of the most precise and largest projects of Earth measurement at that time. In 1860 Friedrich Georg Wilhelm Struve published his Arc du méridien de 25° 20′ entre le Danube et la Mer Glaciale mesuré depuis 1816 jusqu’en 1855. The flattening of the Earth was estimated at 1/294.26 and the Earth's equatorial radius was estimated at 6378360.7 metres. In the early 19th century, the Paris meridian's arc was recalculated with greater precision between Shetland and the Balearic Islands by the French astronomers François Arago and Jean-Baptiste Biot. In 1821 they published their work as a fourth volume following the three volumes of "Bases du système métrique décimal ou mesure de l'arc méridien compris entre les parallèles de Dunkerque et Barcelone" (Basis for the decimal metric system or measurement of the meridian arc comprised between Dunkirk and Barcelona) by Delambre and Méchain. Louis Puissant declared in 1836 in front of the French Academy of Sciences that Delambre and Méchain had


id: history-of-geodesy-20260505-9
file: data/en.wikipedia.org/wiki/History_of_geodesy-9.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
Friedrich Bessel was responsible for the nineteenth-century investigations of the shape of the Earth by means of the pendulum's determination of gravity and the use of Clairaut's theorem. The studies he conducted from 1825 to 1828 and his determination of the length of the pendulum beating the second in Berlin seven years later marked the beginning of a new era in geodesy. Indeed, the reversible pendulum as it was used by geodesists at the end of the 19th century was largely due to the work of Bessel, because neither Johann Gottlieb Friedrich von Bohnenberger, its inventor, nor Henry Kater who used it in 1818 brought the improvements which would result from the precious indications of Bessel, and which converted the reversible pendulum into one of the most admirable instruments which the scientists of the nineteenth century could use. The reversible pendulum built by the Repsold brothers was used in Switzerland in 1865 by Émile Plantamour for the measurement of gravity in six stations of the Swiss geodetic network. Following the example set by this country and under the patronage of the International Geodetic Association, Austria, Bavaria, Prussia, Russia and Saxony undertook gravity determinations on their respective territories. However, these results


id: history-of-geodesy-20260505-10
file: data/en.wikipedia.org/wiki/History_of_geodesy-10.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
As Carlos Ibáñez e Ibáñez de Ibero stated. If precision metrology had needed the help of geodesy, it could not continue to prosper without the help of metrology. Indeed, how to express all the measurements of terrestrial arcs as a function of a single unit, and all the determinations of the force of gravity with the pendulum, if metrology had not created a common unit, adopted and respected by all civilized nations, and if in addition one had not compared, with great precision, to the same unit all the rulers for measuring geodesic bases, and all the pendulum rods that had hitherto been used or would be used in the future? Only when this series of metrological comparisons would be finished with a probable error of a thousandth of a millimeter would geodesy be able to link the works of the different nations one with another, and then proclaim the result of the measurement of the Globe. In 1855, the Dufour map (French: Carte Dufour), the first topographic map of Switzerland for which the metre was adopted as the unit of length, won the gold medal at the Exposition Universelle. However, the baselines for this map were measured in 1834


id: history-of-geodesy-20260505-11
file: data/en.wikipedia.org/wiki/History_of_geodesy-11.md
category: reference
title: History of geodesy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_geodesy
date_saved: 2026-05-05T09:32:04.198645+00:00
instance: kb-cron
parent: history-of-geodesy-20260505-0
summary:
=== Geodesy and mathematics === In 1804 Johann Georg Tralles was made a member of the Berlin Academy of Sciences. In 1810 he became the first holder of the chair of mathematics at the Humboldt University of Berlin. In the same year he was appointed secretary of the mathematics class at the Berlin Academy of Sciences. Tralles maintained an important correspondence with Friedrich Wilhelm Bessel and supported his appointment to the University of Königsberg. In 1809 Carl Friedrich Gauss published his method of calculating the orbits of celestial bodies. In that work he claimed to have been in possession of the method of least squares since 1795. This naturally led to a priority dispute with Adrien-Marie Legendre. However, to Gauss's credit, he went beyond Legendre and succeeded in connecting the method of least squares with the principles of probability and to the normal distribution. He had managed to complete Laplace's program of specifying a mathematical form of the probability density for the observations, depending on a finite number of unknown parameters, and define a method of estimation that minimises the error of estimation. Gauss showed that the arithmetic mean is indeed the best estimate of the location parameter by changing


id: arc-measurement-20260505-0
file: data/en.wikipedia.org/wiki/Arc_measurement-0.md
category: reference
title: Arc measurement
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Arc_measurement
date_saved: 2026-05-05T09:32:05.357865+00:00
instance: kb-cron
parent: arc-measurement-20260505-0
summary:
Arc measurement, sometimes called degree measurement (German: Gradmessung), is the astrogeodetic technique of determining the radius of Earth and, by extension, its circumference. More specifically, it seeks to determine the local Earth radius of curvature of the figure of the Earth, by relating the latitude difference (sometimes also the longitude difference) and the geographic distance (arc length) surveyed between two locations on Earth's surface. The most common variant involves only astronomical latitudes and the meridian arc length and is called meridian arc measurement; other variants may involve only astronomical longitude (parallel arc measurement) or both geographic coordinates (oblique arc measurement). Arc measurement campaigns in Europe were the precursors to the International Association of Geodesy (IAG). Nowadays, the method is replaced by worldwide geodetic networks and by satellite geodesy. == History == The first known arc measurement was performed by Eratosthenes (240 BC) between Alexandria and Syene in what is now Egypt, determining the radius of the Earth with remarkable correctness. In the early 8th century, Yi Xing performed a similar survey. The French physician Jean Fernel measured the arc in 1528. The Dutch geodesist Snellius (~1620) repeated the experiment between Alkmaar and Bergen op Zoom using more modern geodetic instrumentation


id: gromatici-20260505-0
file: data/en.wikipedia.org/wiki/Gromatici-0.md
category: reference
title: Gromatici
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Gromatici
date_saved: 2026-05-05T09:32:06.495473+00:00
instance: kb-cron
parent: gromatici-20260505-0
summary:
Gromatici (from Latin groma or gruma, a surveyor's pole) or agrimensores was the name for land surveyors amongst the ancient Romans. The "gromatic writers" were technical writers who codified their techniques of surveying, most of whose preserved writings are found in the Corpus Agrimensorum Romanorum. == History == === Roman Republic === At the foundation of a colony and the assignation of lands the auspices were taken, for which purpose the presence of the augur was necessary. But the business of the augur did not extend beyond the religious part of the ceremony: the division and measurement of the land were made by professional measurers. These were the finitores mentioned by the early writers, who in the later periods were called mensores and agrimensores. The business of a finitor could only be done by a free man, and the honourable nature of his office is indicated by the rule that there was no bargain for his services, but he received his pay in the form of a gift. These finitores appear also to have acted as judices, under the name of arbitri (single arbiter), in those disputes about boundaries which were purely of a technical, not a legal, character. The


id: gromatici-20260505-1
file: data/en.wikipedia.org/wiki/Gromatici-1.md
category: reference
title: Gromatici
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Gromatici
date_saved: 2026-05-05T09:32:06.495473+00:00
instance: kb-cron
parent: gromatici-20260505-0
summary:
The earliest of the gromatic writers was Frontinus, whose De agrorum qualitate, dealing with the legal aspect of the art, was the subject of a commentary by Aggenus Urbicus, a Christian schoolmaster. Under Trajan a certain Balbus, who had accompanied the emperor on his Dacian campaign, wrote a still extant manual of geometry for land surveyors (Expositio et ratio omnium formarum or mensurarum, probably after a Greek original by Hero), dedicated to a certain Celsus who had invented an improvement in a gromatic instrument (perhaps the dioptra, resembling the modern theodolite); for the treatises of Hyginus see that name. Somewhat later than Trajan was Siculus Flaccus (De condicionibus agrorum, extant), while the most curious treatise on the subject, written in barbarous Latin and entitled Casae litterarum (long a school textbook) is the work of a certain Innocentius (4th-5th century). It is doubtful whether Boetius is the author of the treatises attributed to him. The Gromatici veteres also contains extracts from official registers (probably belonging to the 5th century) of colonial and other land surveys, lists and descriptions of boundary stones, and extracts from the Theodosian Codex. According to Mommsen, the collection had its origin during the 5th century in the


id: meridian-arc-20260505-0
file: data/en.wikipedia.org/wiki/Meridian_arc-0.md
category: reference
title: Meridian arc
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Meridian_arc
date_saved: 2026-05-05T09:32:10.082408+00:00
instance: kb-cron
parent: meridian-arc-20260505-0
summary:
In geodesy and navigation, a meridian arc is the curve between two points near the Earth's surface having the same longitude. The term may refer either to a segment of the meridian, or to its length. Both the practical determination of meridian arcs (employing measuring instruments in field campaigns) and their theoretical calculation (based on geometry and abstract mathematics) have been pursued for many years. == Measurement == The purpose of measuring meridian arcs is to determine a figure of the Earth. One or more measurements of meridian arcs can be used to infer the shape of the reference ellipsoid that best approximates the geoid in the region of the measurements. Measurements of meridian arcs at several latitudes along many meridians around the world can be combined in order to approximate a geocentric ellipsoid intended to fit the entire world. The earliest determinations of the size of a spherical Earth required a single arc. Accurate survey work beginning in the 19th century required several arc measurements in the region the survey was to be conducted, leading to a proliferation of reference ellipsoids around the world. The latest determinations use astro-geodetic measurements and the methods of satellite geodesy to determine reference


id: meridian-arc-20260505-1
file: data/en.wikipedia.org/wiki/Meridian_arc-1.md
category: reference
title: Meridian arc
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Meridian_arc
date_saved: 2026-05-05T09:32:10.082408+00:00
instance: kb-cron
parent: meridian-arc-20260505-0
summary:
== 19th century == From the French revolution of 1789 came an effort to reform measurement standards, leading ultimately to an extravagant effort to measure the meridian passing through Paris in order to define the metre. The question of measurement reform was placed in the hands of the French Academy of Sciences, who appointed a commission chaired by Jean-Charles de Borda. Instead of the seconds pendulum method, the commission of the French Academy of Sciences – whose members included Borda, Lagrange, Laplace, Monge and Condorcet – decided that the new measure should be equal to one ten-millionth of the distance from the North Pole to the Equator (the quadrant of the Earth's circumference), measured along the meridian passing through Paris at the longitude of Paris pantheon, which became the central geodetic station in Paris. Jean Baptiste Joseph Delambre obtained the fundamental co-ordinates of the Pantheon by triangulating all the geodetic stations around Paris from the Pantheon's dome. Apart from the obvious consideration of safe access for French surveyors, the Paris meridian was also a sound choice for scientific reasons: a portion of the quadrant from Dunkirk to Barcelona (about 1000 km, or one-tenth of the total) could be surveyed with


id: meridian-arc-20260505-2
file: data/en.wikipedia.org/wiki/Meridian_arc-2.md
category: reference
title: Meridian arc
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Meridian_arc
date_saved: 2026-05-05T09:32:10.082408+00:00
instance: kb-cron
parent: meridian-arc-20260505-0
summary:
End of November 1798, Delambre and Méchain returned to Paris with their data, having completed the survey to meet a foreign commission composed of representatives of Batavian Republic: Henricus Aeneae and Jean Henri van Swinden, Cisalpine Republic: Lorenzo Mascheroni, Kingdom of Denmark: Thomas Bugge, Kingdom of Spain: Gabriel Císcar and Agustín de Pedrayes, Helvetic Republic: Johann Georg Tralles, Ligurian Republic: Ambrogio Multedo, Kingdom of Sardinia: Prospero Balbo, Antonio Vassali Eandi, Roman Republic: Pietro Franchini, Tuscan Republic: Giovanni Fabbroni who had been invited by Talleyrand. The French commission comprised Jean-Charles de Borda, Barnabé Brisson, Charles-Augustin de Coulomb, Jean Darcet, René Just Haüy, Joseph-Louis Lagrange, Pierre- Simon Laplace, Louis Lefèvre-Ginneau, Pierre Méchain and Gaspar de Prony. In 1799, a commission including Johann Georg Tralles, Jean Henri van Swinden, Adrien-Marie Legendre, Pierre-Simon Laplace, Gabriel Císcar, Pierre Méchain and Jean-Baptiste Delambre calculated the distance from Dunkirk to Barcelona using the data of the triangulation between these two towns and determined the portion of the distance from the North Pole to the Equator it represented. Pierre Méchain's and Jean-Baptiste Delambre's measurements were combined with the results of the French Geodetic Mission to the Equator and a value of ⁠1/334⁠ was found for the Earth's flattening.


id: meridian-arc-20260505-3
file: data/en.wikipedia.org/wiki/Meridian_arc-3.md
category: reference
title: Meridian arc
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Meridian_arc
date_saved: 2026-05-05T09:32:10.082408+00:00
instance: kb-cron
parent: meridian-arc-20260505-0
summary:
m ( φ ) = b ∫ 0 β 1 + e ′ 2 sin 2 ⁡ β d β , {\displaystyle m(\varphi )=b\int _{0}^{\beta }{\sqrt {1+e'^{2}\sin ^{2}\beta }}\,d\beta \,,} where tan β = (1 − f)tan φ and e′2 = ⁠e2/1 − e2⁠. Even though latitude is normally confined to the range [−⁠π/2⁠,⁠π/2⁠], all the formulae given here apply to measuring distance around the complete meridian ellipse (including the anti-meridian). Thus the ranges of φ, β, and the rectifying latitude μ, are unrestricted. === Relation to elliptic integrals === The above integral is related to a special case of an incomplete elliptic integral of the third kind. In the notation of the online NIST handbook (Section 19.2(ii)), m ( φ ) = a ( 1 − e 2 ) Π ( φ , e 2 , e ) . {\displaystyle m(\varphi )=a\left(1-e^{2}\right)\,\Pi (\varphi ,e^{2},e)\,.} It may also be written in terms of incomplete elliptic integrals of the second kind (See the NIST handbook Section 19.6(iv)), m ( φ ) = a ( E ( φ , e ) − e 2 sin ⁡ φ cos ⁡ φ 1 − e 2 sin ⁡ 2 φ ) = a (


id: meridian-arc-20260505-4
file: data/en.wikipedia.org/wiki/Meridian_arc-4.md
category: reference
title: Meridian arc
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Meridian_arc
date_saved: 2026-05-05T09:32:10.082408+00:00
instance: kb-cron
parent: meridian-arc-20260505-0
summary:
Because this series provides an expansion for the elliptic integral of the second kind, it can be used to write the arc length in terms of the geodetic latitude as m ( φ ) = a + b 2 ( B 0 φ − B 2 sin ⁡ 2 φ + B 4 sin ⁡ 4 φ − B 6 sin ⁡ 6 φ + B 8 sin ⁡ 8 φ − ⋯ − 2 n sin ⁡ 2 φ 1 + 2 n cos ⁡ 2 φ + n 2 ) . {\displaystyle {\begin{aligned}m(\varphi )={\frac {a+b}{2}}{\Biggl (}&B_{0}\varphi -B_{2}\sin 2\varphi +B_{4}\sin 4\varphi -B_{6}\sin 6\varphi +B_{8}\sin 8\varphi -\cdots \\[-3mu]&\quad -{\frac {2n\sin 2\varphi }{\sqrt {1+2n\cos 2\varphi +n^{2}}}}{\Biggr )}.\end{aligned}}} ==== Generalized series ==== The above series, to eighth order in eccentricity or fourth order in third flattening, provide millimetre accuracy. With the aid of symbolic algebra systems, they can easily be extended to sixth order in the third flattening which provides full double precision accuracy for terrestrial applications. As described, Delambre and Bessel both wrote their series in a form that allows them to be generalized to arbitrary order. The coefficients in Bessel's series can be expressed particularly simply B 2 k =


id: meridian-arc-20260505-5
file: data/en.wikipedia.org/wiki/Meridian_arc-5.md
category: reference
title: Meridian arc
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Meridian_arc
date_saved: 2026-05-05T09:32:10.082408+00:00
instance: kb-cron
parent: meridian-arc-20260505-0
summary:
== The inverse meridian problem for the ellipsoid == In some problems, we need to be able to solve the inverse problem: given the arc length m, find the latitude φ. This may be solved by Newton's method, iterating φ i + 1 = φ i − m ( φ i ) − m M ( φ i ) , {\displaystyle \varphi _{i+1}=\varphi _{i}-{\frac {m(\varphi _{i})-m}{M(\varphi _{i})}}\,,} until convergence. A suitable starting guess is given by φ0 = μ where μ = π 2 m m p {\displaystyle \mu ={\frac {\pi }{2}}{\frac {m}{m_{\mathrm {p} }}}} is the rectifying latitude. Note that it there is no need to differentiate the series for m(φ), since the formula for the meridian radius of curvature M(φ) can be used instead. Alternatively, Helmert's series for the meridian distance can be reverted to give φ = μ + H 2 ′ sin ⁡ 2 μ + H 4 ′ sin ⁡ 4 μ + H 6 ′ sin ⁡ 6 μ + H 8 ′ sin ⁡ 8 μ + ⋯ {\displaystyle \varphi =\mu +H'_{2}\sin 2\mu +H'_{4}\sin 4\mu +H'_{6}\sin 6\mu +H'_{8}\sin 8\mu +\cdots } where H 2 ′ = 3 2 n − 27 32 n


id: history-of-the-metre-20260505-0
file: data/en.wikipedia.org/wiki/History_of_the_metre-0.md
category: reference
title: History of the metre
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metre
date_saved: 2026-05-05T09:32:11.330739+00:00
instance: kb-cron
parent: history-of-the-metre-20260505-0
summary:
During the French Revolution, the traditional units of measure were to be replaced by consistent measures based on natural phenomena. As a base unit of length, scientists had favoured the seconds pendulum (a pendulum with a half-period of one second) one century earlier, but this was rejected as it had been discovered that this length varied from place to place with local gravity. The mètre was introduced – defined as one ten-millionth of the shortest distance from the North Pole to the equator passing through Paris, assuming an Earth flattening of ⁠1/334⁠. Following the arc measurement of Delambre and Méchain, the historical French official standard of the metre was made available in the form of the Mètre des Archives, a platinum bar held in Paris. It was originally also planned to dematerialise the definition of the metre by counting the number of swings of a one-metre-long pendulum during a day at a latitude of 45°. However, dematerialising the definition of units of length by means of the pendulum would prove less reliable than artefacts. During the mid nineteenth century, following the American Revolution and the decolonisation of the Americas, the metre gained adoption in Americas, particularly in scientific usage, and


id: history-of-the-metre-20260505-1
file: data/en.wikipedia.org/wiki/History_of_the_metre-1.md
category: reference
title: History of the metre
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metre
date_saved: 2026-05-05T09:32:11.330739+00:00
instance: kb-cron
parent: history-of-the-metre-20260505-0
summary:
=== Adoption === In the 19th century, measuring instruments calibrated on the metre were devised for American, Spanish and Egyptian cartography. One of the iron metre standards was brought to the United States in 1805. It became known as the Committee Meter in the United States and served as a standard of length in the United States Coast Survey until 1890. In 1855, the Dufour map (French: Carte Dufour), the first topographic map of Switzerland for which the metre was adopted as the unit of length, won the gold medal at the Exposition Universelle. On the sidelines of the Exposition Universelle (1855) and the second Congress of Statistics held in Paris, an association with a view to obtaining a uniform decimal system of measures, weights and currencies was created in 1855. A Committee for Weights and Measures and Monies (French: Comité des poids, mesures et monnaies) was created during the Exposition Universelle (1867) in Paris and called for the international adoption of the metric system. In the United States, the Metric Act of 1866 allowed the use of the metre in the United States, and in 1867 the General Conference of the European Arc Measurement (German: Europäische Gradmessung) proposed the


id: history-of-the-metre-20260505-2
file: data/en.wikipedia.org/wiki/History_of_the_metre-2.md
category: reference
title: History of the metre
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metre
date_saved: 2026-05-05T09:32:11.330739+00:00
instance: kb-cron
parent: history-of-the-metre-20260505-0
summary:
The unit of length is the metre, defined by the distance, at 0°, between the axes of the two central lines marked on the bar of platinum–iridium kept at the Bureau International des Poids et Mesures and declared Prototype of the metre by the 1st Conférence Générale des Poids et Mesures, this bar being subject to standard atmospheric pressure and supported on two cylinders of at least one centimetre diameter, symmetrically placed in the same horizontal plane at a distance of 571 mm from each other. These support locations are at the Bessel points of the prototype – the support points, separated by 0.5594 of the total length of the bar, that minimise shortening of the bar due to bending under its own weight. Because the prototype is a line standard, its full length is 102 cm, slightly longer than 1 metre. Cross-sectionally, it measures 16 mm × 16 mm. The representation of the unit of length by means of the distance between two fine lines on the surface of a bar of metal at a certain temperature is never itself free from uncertainty and probable error, owing to the difficulty of knowing at any moment the precise temperature of


id: history-of-the-metre-20260505-3
file: data/en.wikipedia.org/wiki/History_of_the_metre-3.md
category: reference
title: History of the metre
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metre
date_saved: 2026-05-05T09:32:11.330739+00:00
instance: kb-cron
parent: history-of-the-metre-20260505-0
summary:
The krypton-86 discharge lamp operating at the triple point of nitrogen (63.14 K, −210.01 °C) was the state-of-the-art light source for interferometry in 1960, but it was soon to be superseded by a new invention: the laser, of which the first working version was constructed in the same year as the redefinition of the metre. Laser light is usually highly monochromatic, and is also coherent (all the light has the same phase, unlike the light from a discharge lamp), both of which are advantageous for interferometry. The shortcomings of the krypton standard were demonstrated by the measurement of the wavelength of the light from a methane-stabilised helium–neon laser (λ ≈ 3.39 μm). The krypton line was found to be asymmetrical, so different wavelengths could be found for the laser light depending on which point on the krypton line was taken for reference. The asymmetry also affected the precision to which the wavelengths could be measured. Developments in electronics also made it possible for the first time to measure the frequency of light in or near the visible region of the spectrum, instead of inferring the frequency from the wavelength and the speed of light. Although visible and infrared frequencies were


id: metre-convention-20260505-0
file: data/en.wikipedia.org/wiki/Metre_Convention-0.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
The Metre Convention (French: Convention du Mètre), also known as the Treaty of the Metre, is an international treaty that was signed in Paris on 20 May 1875 by representatives of 17 nations: Argentina, Austria-Hungary, Belgium, Brazil, Denmark, France, Germany, Italy, Peru, Portugal, Russia, Spain, Sweden and Norway, Switzerland, Ottoman Empire, United States of America, and Venezuela. The treaty created the International Bureau of Weights and Measures (BIPM), an intergovernmental organization, under the authority of the General Conference on Weights and Measures (CGPM) and the supervision of the International Committee for Weights and Measures (CIPM). These organizations coordinate international metrology and the development of internationally recognized systems of measurement. The Metre Convention established a permanent organizational structure for member governments to act in common accord on all matters relating to units of measurement. The governing organs of the BIPM are: The General Conference on Weights and Measures (Conférence générale des poids et mesures or CGPM)—the plenary organ of the BIPM which consists of the delegates of all the contracting governments, and The International Committee for Weights and Measures (Comité international des poids et mesures or CIPM)—the direction and supervision organ composed of 18 prominent metrologists from 18 different member states


id: metre-convention-20260505-1
file: data/en.wikipedia.org/wiki/Metre_Convention-1.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
== Cartography and the metre == The American Revolution, in which the United States was supported by France and Spain, led to the founding of the Survey of the Coast in 1807 and the creation of the Office of Standard Weights and Measures in 1830. During the mid-19th century, the metre was adopted in Khedivate of Egypt an autonomous tributary state of the Ottoman Empire for cadastral surveying. In continental Europe, adoption of the metric system and a better standardisation of units of measurement marked the Technological Revolution, a period in which German Empire would challenge United Kingdom as the foremost industrial nation in Europe. This was accompanied by development in cartography which was a prerequisite for both military operations and the creation of the infrastructures needed for industrial development such as railways. During the process of unification of Germany, geodesists called for the establishment of an International Bureau of Weights and Measures in Europe. === Swiss, American, Spanish and Egyptian cartography === The Helvetic Republic adopted the metric system by law in 1801. In 1805, a Swiss immigrant Ferdinand Rudolph Hassler brought copies of the French metre and kilogram to the United States. In 1830 the Congress decided to


id: metre-convention-20260505-2
file: data/en.wikipedia.org/wiki/Metre_Convention-2.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
In 1816, Ferdinand Rudolph Hassler was appointed first Superintendent of the Survey of the Coast. Trained in geodesy in Switzerland, France and Germany, Hassler had brought a standard metre made in Paris to the United States in October 1805. He designed a baseline apparatus which instead of bringing different bars in actual contact during measurements, used only one bar calibrated on the Committee meter, an authenthic copy of the Mètre des Archives, and optical contact. In 1830, Hassler became head of the Office of Weights and Measures, which became a part of the Survey of the Coast. He compared various units of length used in the United States at that time and measured coefficients of expansion to assess temperature effects on the measurements. In 1834, Hassler, measured at Fire Island the first baseline of the Survey of the Coast, shortly before Louis Puissant declared to the French Academy of Sciences in 1836 that Jean Baptiste Joseph Delambre and Pierre Méchain had made errors in the meridian arc measurement, which had been used to determine the length of the metre. In 1855, the Dufour map (French: Carte Dufour), the first topographic map of Switzerland for which the metre was adopted as


id: metre-convention-20260505-3
file: data/en.wikipedia.org/wiki/Metre_Convention-3.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
=== European geodesy === In Europe, except Spain, surveyors continued to use measuring instruments calibrated on the Toise of Peru. Among these, the toise of Bessel and the apparatus of Borda were respectively the main references for geodesy in Prussia and in France. These measuring devices consisted of bimetallic rulers in platinum and brass or iron and zinc fixed together at one extremity to assess the variations in length produced by any change in temperature. The combination of two bars made of two different metals allowed to take thermal expansion into account without measuring the temperature. A French scientific instrument maker, Jean Nicolas Fortin, made three direct copies of the Toise of Peru, one for Friedrich Georg Wilhelm von Struve, a second for Heinrich Christian Schumacher in 1821 and a third for Friedrich Wilhelm Bessel in 1823. In 1831, Henri-Prudence Gambey also realised a copy of the Toise of Peru which was kept at Altona Observatory in Hamburg. In the second half of the 19th century, the creation of the Central European Arc Measurement (German: Mitteleuropäische Gradmessung) would mark, following Carl Friedrich Gauss, Friedrich Wilhelm Bessel and Friedrich Georg Wilhelm von Struve examples, the systematic adoption of more rigorous methods


id: metre-convention-20260505-4
file: data/en.wikipedia.org/wiki/Metre_Convention-4.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
=== The International Metre Commission (1870/1872) === Prior to the 1870 conference, French politicians had feared that the British might reject the existing metre and would prefer to have new value of its theoretical length. However, James Clerk Maxwell wrote in 1865 that no scientist could become famous proposing a metre deduced from new measurements of the size of the Earth, while Adolphe Hirsch would recall, in his 1891 obituary of Carlos Ibáñez e Ibáñez de Ibero, that the International Metre Commission had decided not to propose a new length for the metre. In July 1870, two weeks before the conference was due to start, the Franco-Prussian War broke out. Although the delegates did meet (without a German delegation), it was agreed that the conference should be recalled once all the delegates (including the German delegation) were present. Following the war, which resulted in Napoleon III's exile, Germany and Italy, now unified nations, adopted the metric system as their national system of units, but with the prototype copy of the kilogram and metre under the control of the French Third Republic. In 1872 the new republican government reissued the invitations and the same year scientists from thirty European and American


id: metre-convention-20260505-5
file: data/en.wikipedia.org/wiki/Metre_Convention-5.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
== The 1875 conferences in Paris == The principal tasks facing the delegates at the 1875 Diplomatic Conference on the Metre was the replacement of the existing metre and kilogram artefacts that were held by the French Government and the setting up of an organization to administer the maintenance of standards around the globe. The conference did not concern itself with other units of measure. The conference had undertones of Franco-German political manoeuvring, particularly since the French had been humiliated by the Prussians during the war a few years previously. Although France lost control of the metric system, they ensured that it passed to international rather than German control and that the international headquarters were in Paris. While the German astronomer Wilhelm Julius Foerster along with the Russian and Austrian representatives had boycotted the Permanent Committee of the International Metre Commission in order to prompt the reunion of the Diplomatic Conference of the Metre and to promote the foundation of a permanent International Bureau of Weights and Measures, Adolphe Hirsch, delegate of Switzerland at this Diplomatic Conference in 1875, conformed to the opinion of Italy and Spain to create, in spite of French reluctance, the International Bureau of Weights and


id: metre-convention-20260505-6
file: data/en.wikipedia.org/wiki/Metre_Convention-6.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
==== General Conference on Weights and Measures ==== The General Conference on Weights and Measures (Conférence générale des poids et mesures or CGPM) is the principal decision-making body put on place by the convention. It is made up of delegates from member states and [non-voting] observers from associate states and economies. The conference usually meets every four years to receive and discuss a report from the CIPM and to endorse new developments in the SI on the advice of the CIPM though at the 2011 meeting, it agreed to meet again in 2014 rather than 2015 to discuss the maturity of the new SI proposals. It is also responsible for new appointments to the CIPM and decides on major issues concerning the development and financing of the BIPM. According to the Metre Convention (Art. 4) the President of the French Academy of Sciences is also the President of the General Conference on Weights and Measures. ==== International Committee for Weights and Measures ==== The International Committee for Weights and Measures (Comité international des poids et mesures or CIPM) is made up of eighteen (originally fourteen) individuals from a member state of high scientific standing, nominated by the CGPM to advise


id: metre-convention-20260505-7
file: data/en.wikipedia.org/wiki/Metre_Convention-7.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
The metre convention was originally drawn up with the main purpose of providing standards of length and mass only. Standards relating to other quantities were under the control of other bodies – time was measured by astronomers, electrical units by a series of ad-hoc international conferences, and other physical standards and concepts were maintained or defined by international bodies such as International Congress of Applied Chemistry or the International Union of Pure and Applied Physics. In 1901 Giorgi published a proposal for building a coherent set of units based on four base units – the metre, kilogram, second and one electrical unit (ampere, volt or ohm). In 1921 the convention was extended to permit the promotion of standards relating to any physical quantity which greatly increased the scope of the CIPM's remit and implicitly giving it freedom to exploit Giorgi's proposals. The 8th CGPM (1933) resolved to work with other international bodies to agree to standards for electrical units that could be related back to the international prototypes. This was agreed in principle by the International Electrotechnical Commission at its congress in Brussels in 1935 subject to the choice of the fourth unit being agreed with, amongst others, the appropriate


id: metre-convention-20260505-8
file: data/en.wikipedia.org/wiki/Metre_Convention-8.md
category: reference
title: Metre Convention
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Metre_Convention
date_saved: 2026-05-05T09:32:12.655343+00:00
instance: kb-cron
parent: metre-convention-20260505-0
summary:
=== Coordination of International Atomic Time === With the advent of the atomic clock it has been possible to define and measure International Atomic Time with sufficient precision that variations in the Earth's rotation can be detected. The International Earth Rotation Service monitors these changes relative to the stars at regular intervals and proposes leap seconds as and when these are needed. Currently there are over 200 atomic clocks in over 50 national laboratories around the world and the BIPM, in terms of the mandate given to it under the Metre Convention, coordinates the various atomic clocks. === New SI === After 1960, when the definition of the metre was linked to a particular wavelength of light rather than the international prototype of the metre, the only unit of measure that remained dependent on a particular artefact was the kilogram. Over the years, small drifts which could be as high as 20×10−9 kilograms per annum in the mass of the international prototype of the kilogram were detected. At the 21st meeting of the CGPM (1999), national laboratories were urged to investigate ways of breaking the link between the kilogram and a specific artefact. Independently of this drift having been identified,


id: history-of-the-metric-system-20260505-0
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-0.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
The history of the metric system began during the Age of Enlightenment with measures of length and weight derived from nature, along with their decimal multiples and fractions. The system became the standard of France and Europe within half a century. Other measures with unity ratios were added, and the system went on to be adopted across the world. The first practical realisation of the metric system came in 1799, during the French Revolution, after the existing system of measures had become impractical for trade, and was replaced by a decimal system based on the kilogram and the metre. The basic units were taken from the natural world. The unit of length, the metre, was based on the dimensions of the Earth, and the unit of mass, the kilogram, was based on the mass of a volume of water of one litre (a cubic decimetre). Reference copies for both units were manufactured in platinum and remained the standards of measure for the next 90 years. After a period of reversion to the mesures usuelles due to unpopularity of the metric system, the metrication of France and much of Europe was complete by the 1850s. In the middle of the 19th


id: history-of-the-metric-system-20260505-1
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-1.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
=== Clocks and pendulums === In 1656, Dutch scientist Christiaan Huygens invented the pendulum clock, with its pendulum marking the seconds. This gave rise to proposals to use its length as a standard unit. But it became apparent that the pendulum lengths of calibrated clocks in different locations varied (due to local variations in the acceleration due to gravity), and this was not a good solution. A more uniform standard was needed. In 1670, Gabriel Mouton, a French abbot and astronomer, published the book Observationes diametrorum solis et lunae apparentium ("Observations of the apparent diameters of the Sun and Moon") in which he proposed a decimal system of measurement of length for use by scientists in international communication, to be based on the dimensions of the Earth. The milliare would be defined as a minute of arc along a meridian (such as the Paris meridian) and would be divided into 10 centuria, the centuria into 10 decuria and so on, successive units being the virga, virgula, decima, centesima, and the millesima. Mouton used Riccioli's estimate that one degree of arc was 321,185 Bolognese feet. Mouton's experiments showed that a pendulum of length one virgula would beat 3959.2 times in half


id: history-of-the-metric-system-20260505-2
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-2.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
In 1790, a panel of five leading French scientists was appointed by the Académie des sciences to investigate weights and measures. They were Jean-Charles de Borda, Joseph-Louis Lagrange, Pierre-Simon Laplace, Gaspard Monge, and Nicolas de Condorcet. Over the following year, the panel, after studying various alternatives, made a series of recommendations regarding a new system of weights and measures, including that it should have a decimal radix, that the unit of length should be based on a fractional arc of a quadrant of the Earth's meridian, and that the unit of weight should be that of a cube of water whose dimension was a decimal fraction of the unit of length. The proposals were accepted by the French Assembly on 30 March 1791. Following acceptance, the Académie des sciences was instructed to implement the proposals. The Académie broke the tasks into five operations, allocating each part to a separate working group: Measuring the difference in latitude between Dunkirk and Barcelona and triangulating between them Measuring the baselines used for the survey Verifying the length of the second pendulum at 45° latitude. Verifying the weight in a vacuum of a given volume of distilled water. Publishing conversion tables relating the new


id: history-of-the-metric-system-20260505-3
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-3.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
Delambre used a baseline of about 10 km in length along a straight road, located close to Melun. In an operation taking six weeks, the baseline was accurately measured using four platinum rods, each of length two toises (about 3.9 m). Thereafter he used, where possible, the triangulation points used by Cassini in his 1744 survey of France. Méchain's baseline, of a similar length, and also on a straight section of road was in the Perpignan area. Although Méchain's sector was half the length of Delambre, it included the Pyrenees and hitherto unsurveyed parts of Spain. After the two surveyors met, each computed the other's baseline in order to cross-check their results and they then recomputed the metre as 443.296 lignes, notably shorter than the 1795 provisional value of 443.44 lignes. On 15 November 1798, Delambre and Méchain returned to Paris with their data, having completed the survey. The final value of the mètre was defined in 1799 as the computed value from the survey. Historical note: It soon became apparent that Méchain and Delambre's result (443.296 lignes) was slightly too short for the meridional definition of the metre. Méchain had made a small error measuring the latitude of Barcelona,


id: history-of-the-metric-system-20260505-4
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-4.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
=== The first structured metric system: CGS === In 1861, a committee of the British Association for the Advancement of Science (BAAS) including William Thomson (later Lord Kelvin), James Clerk Maxwell, and James Prescott Joule among its members was tasked with investigating the "Standards of Electrical Resistance". In their first report (1862), they laid the ground rules for their work—the metric system was to be used, measures of electrical energy must have the same units as measures of mechanical energy, and two sets of electromagnetic units would have to be derived—an electromagnetic system and an electrostatic system. In the second report (1863), they introduced the concept of a coherent system of units whereby units of length, mass, and time were identified as "fundamental units" (now known as base units). All other units of measure could be derived (hence derived units) from these base units. The metre, gram, and second were chosen as base units. In 1861, before a meeting of the BAAS, Charles Bright and Latimer Clark proposed the names of ohm, volt, and farad in honour of Georg Ohm, Alessandro Volta, and Michael Faraday respectively for the practical units based on the CGS absolute system. This was supported by


id: history-of-the-metric-system-20260505-5
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-5.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
==== Quadrant–eleventhgram–second (QES) or International System of Electrical and Magnetic Units ==== The CGS units of measure used in scientific work were not practical for engineering, leading to the development of a more applicable system of electric units especially for telegraphy. The unit of length was 107 m (the hebdometre, nominally the Earth quadrant), the unit of mass was an unnamed unit equal to 10−11 g and the unit of time was the second. The units of mass and length were scaled incongruously to yield more consistent and usable electric units in terms of mechanical measures. Informally called the "practical" system, it was properly termed the quadrant–eleventhgram–second (QES) system of units according to convention. The definitions of electrical units incorporated the magnetic constant like the EMU system, and the names of the units were carried over from that system, but scaled according to the defined mechanical units. The system was formalised as the International system late in the 19th century and its units later designated the "international ampere", "international volt", etc. ==== Heaviside–Lorentz system of units ==== The factor 4 π {\displaystyle 4\pi } that occurs in Maxwell's equations in the gaussian system (and the other CGS systems) comes from


id: history-of-the-metric-system-20260505-6
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-6.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
Conférence générale des poids et mesures (CGPM or General Conference on Weights and Measures), an intergovernmental conference of official delegates of member nations and the supreme authority for all actions; Comité international des poids et mesures (CIPM or International Committee for Weights and Measures), consisting of selected scientists and metrologists, which prepares and executes the decisions of the CGPM and is responsible for the supervision of the International Bureau of Weights and Measures; Bureau international des poids et mesures (BIPM or International Bureau of Weights and Measures), a permanent laboratory and world centre of scientific metrology, the activities of which include the establishment of the basic standards and scales of the principal physical quantities, maintenance of the international prototype standards, and oversight of regular comparisons between the international prototype and the various national standards. The international prototype of the metre and international prototype of the kilogram were both made from a 90% platinum, 10% iridium alloy which is exceptionally hard and which has good electrical and thermal conductivity properties. The prototype had a special X-shaped (Tresca) cross section to minimise the effects of torsional strain during length comparisons and the prototype kilograms were cylindrical in shape. The London firm Johnson


id: history-of-the-metric-system-20260505-7
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-7.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
== Working draft of SI: Practical system of units == The 9th CGPM met in 1948, fifteen years after the 8th CGPM. In response to formal requests made by the International Union of Pure and Applied Physics and by the French government to establish a practical system of units of measure, the CGPM requested the CIPM to prepare recommendations for a single practical system of units of measurement, suitable for adoption by all countries adhering to the Metre Convention. The CIPM's draft proposal was an extensive revision and simplification of the metric unit definitions, symbols, and terminology based on the MKS system of units. Following astronomical observations, the second was set as a fraction of the year 1900. The electromagnetic base unit, as required by Giorgi, was accepted as the ampere. After negotiations with the CIS and IUPAP, two additional units—the degree kelvin and the candela—were also proposed as base units. For the first time, the CGPM made recommendations concerning derived units. At the same time, the CGPM adopted conventions for the writing and printing of unit symbols and numbers and catalogued the symbols for the most important MKS and CGS units of measure. === Time === Until the advent


id: history-of-the-metric-system-20260505-8
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-8.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
=== New base and derived units === Over the ensuing years, the BIPM developed and maintained cross-correlations relating various measuring devices such as thermocouples, light spectra, and the like to the equivalent temperatures. The mole was originally known as a gram-atom or a gram-molecule—the amount of a substance measured in grams divided by its atomic weight. Originally chemists and physicists had differing views regarding the definition of the atomic weight—both assigned a value of 16 atomic mass units (amu) to oxygen, but physicists defined oxygen in terms of the 16O isotope whereas chemists assigned 16 amu to 16O, 17O and 18O isotopes mixed in the proportion that they occur in nature. Finally, an agreement between the International Union of Pure and Applied Physics (IUPAP) and the International Union of Pure and Applied Chemistry (IUPAC) brought this duality to an end in 1959/60, both parties agreeing to define the atomic weight of 12C as being exactly 12 amu. This agreement was confirmed by ISO and in 1969 the CIPM recommended its inclusion in SI as a base unit. This was done in 1971 at the 14th CGPM. === Start of migration to constant definitions === The second major trend in the


id: history-of-the-metric-system-20260505-9
file: data/en.wikipedia.org/wiki/History_of_the_metric_system-9.md
category: reference
title: History of the metric system
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_the_metric_system
date_saved: 2026-05-05T09:32:14.191782+00:00
instance: kb-cron
parent: history-of-the-metric-system-20260505-0
summary:
At its 23rd meeting (2007), the CGPM mandated the CIPM to investigate the use of natural constants as the basis for all units of measure rather than the artefacts that were then in use. The following year, this was endorsed by the International Union of Pure and Applied Physics (IUPAP). At a meeting of the CCU held in Reading, United Kingdom, in September 2010, a resolution and draft changes to the SI brochure that were to be presented to the next meeting of the CIPM in October 2010 were agreed in principle. The CIPM meeting of October 2010 found that "the conditions set by the General Conference at its 23rd meeting have not yet been fully met. For this reason the CIPM does not propose a revision of the SI at the present time". The CIPM, however, presented a resolution for consideration at the 24th CGPM (17–21 October 2011) to agree to the new definitions in principle, but not to implement them until the details had been finalised. In the revision, four of the seven SI base units—the kilogram, ampere, kelvin, and mole—were redefined by setting exact numerical values for the Planck constant (h), the elementary electric charge (e), the


id: timeline-of-international-kilogram-prototypes-20260505-0
file: data/en.wikipedia.org/wiki/Timeline_of_International_Kilogram_Prototypes-0.md
category: reference
title: Timeline of International Kilogram Prototypes
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Timeline_of_International_Kilogram_Prototypes
date_saved: 2026-05-05T09:32:15.482306+00:00
instance: kb-cron
parent: timeline-of-international-kilogram-prototypes-20260505-0
summary:
Official copies of the International Prototype of the Kilogram (IPK), the 1 kg platinum–iridium alloy right circular cylinders, disseminated the kilogram from 1889 until the redefinition based on physical constants in 2019. These prototypes underpinned global trust in scientific discovery, industrial manufacturing, and international trade for over a century. Under the Metre Convention's framework for international collaboration in metrology, the pure platinum "Kilogram of the Archives" standard from 1799 was replaced by the platinum–iridium International Prototype of the Kilogram (IPK) in 1879. Pure platinum was too soft for a durable mass standard, but the addition of just 10% iridium in the alloy greatly increased hardness while still retaining extreme resistance to oxidation, extremely high density, and low magnetic susceptibility. The harder alloy reduced wear and allowed the prototypes to be finished to a high polish, minimising variability. The IPK and six sister copies are stored under secure environmental controls at the International Bureau of Weights and Measures (BIPM) in the Pavillon de Breteuil. Other copies, manufactured primarily by Johnson Matthey beginning in 1879, were distributed to national metrology institutes of countries that had ratified and conformed to the Treaty of the Metre (and to certain non‑national organisations). Each copy carries


id: history-of-time-in-the-united-states-20260505-0
file: data/en.wikipedia.org/wiki/History_of_time_in_the_United_States-0.md
category: reference
title: History of time in the United States
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_time_in_the_United_States
date_saved: 2026-05-05T09:32:21.245464+00:00
instance: kb-cron
parent: history-of-time-in-the-united-states-20260505-0
summary:
On November 18, 1883, United States and Canadian railroads instituted standard time in time zones. Before then, time of day was a local matter, and most cities and towns used some form of local solar time, maintained by some well-known clock (for example, on a church steeple or in a jeweler's window). The standard time system was not immediately embraced by all. Standard time in time zones was established in U.S. law in the Standard Time Act on March 19, 1918, at which time daylight saving time was also instituted. Use of standard time gradually increased because of its obvious practical advantages for communication and travel. Standard time in time zones was established in U.S. law in the Standard Time Act on March 19, 1918. The act established daylight saving time, which was and is a contentious idea. Daylight saving time was repealed in 1919, but standard time in time zones remained in law, with the Interstate Commerce Commission (ICC) having the authority over time zone boundaries. Daylight time became a local matter; ultimately, it was reinstated nationally early in World War II and was continuously observed until the end of the war. After the war its use varied among


id: history-of-time-in-the-united-states-20260505-1
file: data/en.wikipedia.org/wiki/History_of_time_in_the_United_States-1.md
category: reference
title: History of time in the United States
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_time_in_the_United_States
date_saved: 2026-05-05T09:32:21.245464+00:00
instance: kb-cron
parent: history-of-time-in-the-united-states-20260505-0
summary:
From 1945 to 1966 U.S. federal law did not address DST. States and cities were free to observe DST or not, and most places that did observe DST did so from the last Sunday in April to the last Sunday in September. In the mid-1950s many areas in the northeastern United States began extending DST to the last Sunday in October. The lack of standardization led to a patchwork where some areas observed DST while adjacent areas did not, and it was not unheard of to have to reset a clock several times during a short trip (e.g., bus drivers operating on West Virginia Route 2 between Moundsville, West Virginia, and Steubenville, Ohio, had to reset their watches seven times over 35 miles). == Uniform Time Act == In the mid-1960s the airline and other transportation industries lobbied for uniformity of DST dates in the United States. The federal Uniform Time Act became law on April 13, 1966, and it mandated that DST begin nationwide on the last Sunday in April and end on the last Sunday in October, effective in 1967. The act explicitly preempted all previously enacted state laws related to the beginning and ending of DST effective


id: history-of-time-in-the-united-states-20260505-2
file: data/en.wikipedia.org/wiki/History_of_time_in_the_United_States-2.md
category: reference
title: History of time in the United States
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_time_in_the_United_States
date_saved: 2026-05-05T09:32:21.245464+00:00
instance: kb-cron
parent: history-of-time-in-the-united-states-20260505-0
summary:
=== Controversy === Since DST moves sunrise one hour later by the clock, late sunrise times become a problem when DST is observed either too far before the March equinox or too far after the September equinox. Because of this, the extension was greeted with criticism by those concerned for the safety of children who would have been forced to travel to school before sunrise, especially in the month of March. In addition, the airline industry was especially concerned if DST were to be extended through to the last Sunday in November, as this is very often the Sunday after Thanksgiving (except for 2013, 2019, 2024, and 2030), as this is always the Sunday after the fourth Friday in November, and Thanksgiving is on the fourth Thursday in November. This is one of the busiest travel days at American airports, and could have resulted in much havoc among travelers who forgot that the clocks were changing that day. If the original proposal to extend DST through the last Sunday in November had been adopted, the entire United States, with the exception of the states that exempted themselves, would have experienced the latest sunrises of the year during the month of


id: history-of-timekeeping-devices-20260505-0
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-0.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
The history of timekeeping devices dates back to when ancient civilizations first observed astronomical bodies as they moved across the sky. Devices and methods for keeping time have gradually improved through a series of new inventions, starting with measuring time by continuous processes, such as the flow of liquid in water clocks, to mechanical clocks, and eventually repetitive, oscillatory processes, such as the swing of pendulums. Oscillating timekeepers are used in modern timepieces. Sundials and water clocks were first used in ancient Egypt c. 1200 BC and later by the Babylonians, the Greeks and the Chinese. Incense clocks were being used in China by the 6th century. In the medieval period, Islamic water clocks were unrivalled in their sophistication until the mid-14th century. The hourglass, invented in Europe, was one of the few reliable methods of measuring time at sea. In medieval Europe, purely mechanical clocks were developed after the invention of the bell-striking alarm, used to signal the correct time to ring monastic bells. The weight-driven mechanical clock controlled by the action of a verge and foliot was a synthesis of earlier ideas from European and Islamic science. Mechanical clocks were a major breakthrough, one notably designed and built


id: history-of-timekeeping-devices-20260505-1
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-1.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
And Isaiah said, This sign shalt thou have of the Lord, that the Lord will do the thing that he hath spoken: shall the shadow go forward ten degrees, or go back ten degrees? And Hezekiah answered, It is a light thing for the shadow to go down ten degrees: nay, but let the shadow return backward ten degrees. And Isaiah the prophet cried unto the Lord: and he brought the shadow ten degrees backward, by which it had gone down in the dial of Ahaz. A clay tablet from the late Babylonian period describes the lengths of shadows at different times of the year. The Babylonian writer Berossos (fl. 3rd century BC) is credited by the Greeks with the invention of a hemispherical sundial hollowed out of stone; the path of the shadow was divided into 12 parts to mark the time. Greek sundials evolved to become highly sophisticated—Ptolemy's Analemma, written in the 2nd century AD, used an early form of trigonometry to derive the position of the Sun from data such as the hour of day and the geographical latitude. The Romans inherited the sundial from the Greeks. The first sundial in Rome arrived in 264 BC, looted


id: history-of-timekeeping-devices-20260505-2
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-2.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
The Greek philosophers Anaxagoras and Empedocles both referred to water clocks that were used to enforce time limits or measure the passing of time. The Athenian philosopher Plato is supposed to have invented an alarm clock that used lead balls cascading noisily onto a copper platter to wake his students. A problem with most clepsydrae was the variation in the flow of water due to the change in fluid pressure, which was addressed from 100 BC when the clock's water container was given a conical shape. They became more sophisticated when innovations such as gongs and moving mechanisms were included. There is strong evidence that the 1st century BC Tower of the Winds in Athens once had a water clock, and a wind vane, as well as the nine vertical sundials still visible on the outside. In Greek tradition, clepsydrae were used in court, a practise later adopted by the Ancient Romans. Ibn Khalaf al-Muradi in medieval Al-Andalus described a water clock that employed both segmental and epicyclic gearing. Islamic water clocks, which used complex gear trains and included arrays of automata, were unrivalled in their sophistication until the mid-14th century. Liquid-driven mechanisms (using heavy floats and a constant-head system)


id: history-of-timekeeping-devices-20260505-3
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-3.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
The 12th-century Muslim inventor Al-Jazari described four different designs for a candle clock in his book Book of Knowledge of Ingenious Mechanical Devices. His so-called "scribe" candle clock was invented to mark the passing of 14 hours of equal length: a precisely engineered mechanism caused a candle of specific dimensions to be slowly pushed upwards, which caused an indicator to move along a scale. The hourglass was one of the few reliable methods of measuring time at sea, and it has been speculated that it was used on board ships as far back as the 11th century, when it would have complemented the compass as an aid to navigation. The earliest unambiguous evidence of the use of an hourglass appears in the painting Allegory of Good Government, by the Italian artist Ambrogio Lorenzetti, from 1338. The Portuguese navigator Ferdinand Magellan used 18 hourglasses on each ship during his circumnavigation of the globe in 1522. Though used in China, the hourglass's history there is unknown, but does not seem to have been used before the mid-16th century, as the hourglass implies the use of glassblowing, then an entirely European and Western art. From the 15th century onwards, hourglasses were used in


id: history-of-timekeeping-devices-20260505-4
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-4.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
The invention of the verge and foliot escapement in c.1275 was one of the most important inventions in both the history of the clock and the history of technology. It was the first type of regulator in horology. A verge, or vertical shaft, is forced to rotate by a weight-driven crown wheel, but is stopped from rotating freely by a foliot. The foliot, which cannot vibrate freely, swings back and forth, which allows a wheel to rotate one tooth at a time. Although the verge and foliot was an advancement on previous timekeepers, it was impossible to avoid fluctuations in the beat caused by changes in the applied forces—the earliest mechanical clocks were regularly reset using a sundial. At around the same time as the invention of the escapement, the Florentine poet Dante Alighieri used clock imagery to depict the souls of the blessed in Paradiso, the third part of the Divine Comedy, written in the early part of the 14th century. It may be the first known literary description of a mechanical clock. There are references to house clocks from 1314 onwards; by 1325 the development of the mechanical clock can be assumed to have occurred. Large mechanical clocks


id: history-of-timekeeping-devices-20260505-5
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-5.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
=== Pendulum clocks === The first accurate timekeepers depended on the phenomenon known as harmonic motion, in which the restoring force acting on an object moved away from its equilibrium position—such as a pendulum or an extended spring—acts to return the object to that position, and causes it to oscillate. Harmonic oscillators can be used as accurate timekeepers as the period of oscillation does not depend on the amplitude of the motion—and so it always takes the same time to complete one oscillation. The period of a harmonic oscillator is completely dependent on the physical characteristics of the oscillating system and not the starting conditions or the amplitude. The period when clocks were controlled by harmonic oscillators was the most productive era in timekeeping. The first invention of this type was the pendulum clock, which was designed and built by Dutch polymath Christiaan Huygens in 1656. Early versions erred by less than one minute per day, and later ones only by 10 seconds, very accurate for their time. Dials that showed minutes and seconds became common after the increase in accuracy made possible by the pendulum clock. Brahe used clocks with minutes and seconds to observe stellar positions. The pendulum


id: history-of-timekeeping-devices-20260505-6
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-6.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
=== Marine chronometer === After the Scilly naval disaster of 1707, in which four ships were wrecked as a result of navigational mistakes, the British government offered a prize of £20,000, equivalent to millions of pounds today, for anyone who could determine the longitude to within 50 kilometres (31 mi) at a latitude just north of the equator. The position of a ship at sea could be determined to within 100 kilometres (62 mi) if a navigator could refer to a clock that lost or gained less than about six seconds per day. Proposals were examined by a newly created Board of Longitude. Among the many people who attempted to claim the prize was the Yorkshire clockmaker Jeremy Thacker, who first used the term chronometer in a pamphlet published in 1714. Huygens built the first sea clock, designed to remain horizontal aboard a moving ship, but that stopped working if the ship moved suddenly. In 1715, at the age of 22, John Harrison had used his carpentry skills to construct a wooden eight-day clock. His clocks had innovations that included the use of wooden parts to remove the need for additional lubrication (and cleaning), rollers to reduce friction, a new


id: history-of-timekeeping-devices-20260505-7
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-7.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
The first wristwatches were made in the 16th century. Elizabeth I of England had made an inventory in 1572 of the watches she acquired, all of which were considered to be part of her jewellery collection. The first pocketwatches were inaccurate, as their size precluded them from having sufficiently well-made moving parts. Unornamented watches began to appear in c. 1625. Dials that showed minutes and seconds became common after the increase in accuracy made possible by the balance spring (or hairspring). Invented separately in 1675 by Huygens and Hooke, it enabled the oscillations of the balance wheel to have a fixed frequency. The invention resulted in a great advance in the accuracy of the mechanical watch, from around half an hour to within a few minutes per day. Some dispute remains as to whether the balance spring was first invented by Huygens or by Hooke; both scientists claimed to have come up with the idea of the balance spring first. Huygens' design for the balance spring is the type used in virtually all watches up to the present day. Thomas Tompion was one of the first clockmakers to recognise the potential of the balance spring and use it successfully in


id: history-of-timekeeping-devices-20260505-8
file: data/en.wikipedia.org/wiki/History_of_timekeeping_devices-8.md
category: reference
title: History of timekeeping devices
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_timekeeping_devices
date_saved: 2026-05-05T09:32:22.439680+00:00
instance: kb-cron
parent: history-of-timekeeping-devices-20260505-0
summary:
Atomic clocks are the most accurate timekeeping devices in practical use today. Accurate to within a few seconds over many thousands of years, they are used to calibrate other clocks and timekeeping instruments. The U.S. National Bureau of Standards (NBS, now National Institute of Standards and Technology (NIST)) changed the way it based the time standard of the United States from quartz to atomic clocks in the 1960s. The idea of using atomic transitions to measure time was first suggested by the British scientist Lord Kelvin in 1879, although it was only in the 1930s with the development of magnetic resonance that there was a practical method for measuring time in this way. A prototype ammonia maser device was built in 1948 at NIST. Although less accurate than existing quartz clocks, it served to prove the concept of an atomic clock. The first accurate atomic clock, a caesium standard based on a certain transition of the caesium-133 atom, was built by the English physicist Louis Essen in 1955 at the National Physical Laboratory in London. It was calibrated by the use of the astronomical time scale ephemeris time (ET). In 1967 the International System of Units (SI) standardized its unit


id: timeline-of-temperature-and-pressure-measurement-technology-20260505-0
file: data/en.wikipedia.org/wiki/Timeline_of_temperature_and_pressure_measurement_technology-0.md
category: reference
title: Timeline of temperature and pressure measurement technology
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Timeline_of_temperature_and_pressure_measurement_technology
date_saved: 2026-05-05T09:32:23.695180+00:00
instance: kb-cron
parent: timeline-of-temperature-and-pressure-measurement-technology-20260505-0
summary:
This is a timeline of temperature and pressure measurement technology or the history of temperature measurement and pressure measurement technology. == Timeline == === 1500s === 1592–1593 — Galileo Galilei builds a device showing variation of hotness known as the thermoscope using the contraction of air to draw water up a tube. === 1600s === 1612 — Santorio Sanctorius makes the first thermometer for medical use. 1617 — Giuseppe Biancani published the first clear diagram of a thermoscope 1624 — The word thermometer (in its French form) first appeared in La Récréation Mathématique by Jean Leurechon, who describes one with a scale of 8 degrees. 1629 — Joseph Solomon Delmedigo describes in a book an accurate sealed-glass thermometer that uses brandy 1638 — Robert Fludd the first thermoscope showing a scale and thus constituting a thermometer. 1643 — Evangelista Torricelli invents the mercury barometer 1654 — Ferdinando II de' Medici, Grand Duke of Tuscany, made sealed tubes part filled with alcohol, with a bulb and stem, the first modern-style thermometer, depending on the expansion of a liquid, and independent of air pressure 1669 — Honoré Fabri suggested using a temperature scale by dividing into 8 equal parts the interval between


id: history-of-watches-20260505-0
file: data/en.wikipedia.org/wiki/History_of_watches-0.md
category: reference
title: History of watches
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_watches
date_saved: 2026-05-05T09:32:26.101091+00:00
instance: kb-cron
parent: history-of-watches-20260505-0
summary:
The history of watches began in 16th-century Europe, where watches evolved from portable spring-driven clocks, which first appeared in the 15th century. The watch was developed by inventors and engineers from the 16th century to the mid-20th century as a mechanical device, powered by winding a mainspring which turned gears and then moved the hands; it kept time with a rotating balance wheel. In the 1960s the invention of the quartz watch which ran on electricity and kept time with a vibrating quartz crystal, proved a radical departure for the watchmaking industry. During the 1980s quartz watches took over the market from mechanical watches, a process referred to as the "quartz crisis". Although mechanical watches still sell in the watch market, the vast majority of watches as of 2020 have quartz movements. One account of the origin of the word "watch" suggests that it came from the Old English word woecce which meant "watchman", because town watchmen used watches to keep track of their shifts. Another theory surmises that the term came from 17th-century sailors, who used the new mechanisms to time the length of their shipboard watches (duty shifts). The Oxford English Dictionary records the word watch in association


id: history-of-watches-20260505-1
file: data/en.wikipedia.org/wiki/History_of_watches-1.md
category: reference
title: History of watches
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_watches
date_saved: 2026-05-05T09:32:26.101091+00:00
instance: kb-cron
parent: history-of-watches-20260505-0
summary:
== Pocket watch == Styles changed in the 17th century and men began to wear watches in pockets instead of as pendants (the woman's watch remained a pendant into the 20th century). This is said to have occurred in 1675 when Charles II of England introduced waistcoats. This was not just a matter of fashion or prejudice; watches of the time were notoriously prone to fouling from exposure to the elements, and could only reliably be kept safe from harm if carried securely in the pocket. To fit in pockets, their shape evolved into the typical pocket watch shape, rounded and flattened with no sharp edges. Glass was used to cover the face beginning around 1610. Watch fobs began to be used, the name originating from the German word fuppe, a pocket. Later in the 1800s Prince Albert, the consort to Queen Victoria, introduced the 'Albert chain' accessory, designed to secure the pocket watch to the man's outergarment by way of a clip. The watch was wound and also set by opening the back and fitting a key to a square arbor, and turning it. The timekeeping mechanism in these early pocket watches was the same one used in clocks,


id: history-of-watches-20260505-2
file: data/en.wikipedia.org/wiki/History_of_watches-2.md
category: reference
title: History of watches
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_watches
date_saved: 2026-05-05T09:32:26.101091+00:00
instance: kb-cron
parent: history-of-watches-20260505-0
summary:
The lever escapement, invented by Thomas Mudge in 1754 and improved by Josiah Emery in 1785, gradually came into use from about 1800 onwards, chiefly in Britain; it was also adopted by Abraham-Louis Breguet, but Swiss watchmakers (who by now were the chief suppliers of watches to most of Europe) mostly adhered to the cylinder until the 1860s. By about 1900, however, the lever was used in almost every watch made. In this escapement the escape wheel pushed on a T-shaped 'lever', which was unlocked as the balance wheel swung through its centre position and gave the wheel a brief push before releasing it. The advantages of the lever was that it allowed the balance wheel to swing completely free during most of its cycle; due to 'locking' and 'draw' its action was very precise; and it was self-starting, so if the balance wheel was stopped by a jar it would start again. Jewel bearings, introduced in England in 1702 by the Swiss mathematician Nicolas Fatio de Duillier, also came into use for quality watches during this period. Watches of this period are characterised by their thinness. New innovations, such as the cylinder and lever escapements, allowed watches to become


id: history-of-watches-20260505-3
file: data/en.wikipedia.org/wiki/History_of_watches-3.md
category: reference
title: History of watches
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_watches
date_saved: 2026-05-05T09:32:26.101091+00:00
instance: kb-cron
parent: history-of-watches-20260505-0
summary:
From the beginning, wristwatches were almost exclusively worn by women, while men used pocket watches up until the early 20th century. The concept of the wristwatch goes back to the production of the very earliest watches in the 16th century. Some people say the world's first wristwatch was created by Abraham-Louis Breguet for Caroline Murat, Queen of Naples, in 1810. By the mid nineteenth century, most watchmakers produced a range of wristwatches, often marketed as bracelets, for women. Founded in 1832, Longines was the world's first watch trademark and the first Swiss company to assemble watches under one roof. Wristwatches were first worn by military men towards the end of the nineteenth century, when the importance of synchronizing maneuvers during war without potentially revealing the plan to the enemy through signaling was increasingly recognized. It was clear that using pocket watches while in the heat of battle or while mounted on a horse was impractical, so officers began to strap the watches to their wrist. The Garstin Company of London patented a 'Watch Wristlet' design in 1893, although they were probably producing similar designs from the 1880s. Officers in the British Army began using wristwatches during colonial military campaigns in


id: history-of-watches-20260505-4
file: data/en.wikipedia.org/wiki/History_of_watches-4.md
category: reference
title: History of watches
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_watches
date_saved: 2026-05-05T09:32:26.101091+00:00
instance: kb-cron
parent: history-of-watches-20260505-0
summary:
The first quartz watch to enter production was the Seiko 35 SQ Astron, which hit the shelves on 25 December 1969, which was the world's most accurate wristwatch to date. Since the technology having been developed by contributions from Japanese, American and Swiss, nobody could patent the whole movement of the quartz wristwatch, thus allowing other manufacturers to participate in the rapid growth and development of the quartz watch market. This ended — in less than a decade — almost 100 years of dominance by the mechanical wristwatch. The introduction of the quartz watch in 1969 was a revolutionary improvement in watch technology. In place of a balance wheel which oscillated at 5 beats per second, it used a quartz crystal resonator which vibrated at 8,192 Hz, driven by a battery-powered oscillator circuit. In place of a wheel train to add up the beats into seconds, minutes, and hours, it used digital counters. The higher Q factor of the resonator, along with quartz's low temperature coefficient, resulted in better accuracy than the best mechanical watches, while the elimination of all moving parts made the watch more shock-resistant and eliminated the need for periodic cleaning. The first digital electronic watch with


id: history-of-watches-20260505-5
file: data/en.wikipedia.org/wiki/History_of_watches-5.md
category: reference
title: History of watches
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_watches
date_saved: 2026-05-05T09:32:26.101091+00:00
instance: kb-cron
parent: history-of-watches-20260505-0
summary:
A smartwatch is a computer worn on the wrist, a wireless digital device that may have the capabilities of a cellphone, portable music player, or a personal digital assistant. By the early 2010s some had the general capabilities of a smartphone, having a processor with a mobile operating system capable of running a variety of mobile apps. The first smartwatch was the Linux Watch, developed in 1998 by Steve Mann which he presented on February 7, 2000. Seiko launched the Ruputer in Japan- it was a wristwatch computer and it had a 3.6 MHz processor. In 1999, Samsung launched the world's first watch phone. It was named the SPH-WP10. It had a built-in speaker and mic, a protruding antenna and a monochrome LCD screen and 90 minutes of talk time. IBM made a prototype of a wristwatch that was running the Linux operating system. The first version had 6 hours battery life and it got extended to 12 in its more advanced version. It was improved by IBM with an accelerometer, a vibrating mechanism and a fingerprint sensor. IBM joined with Citizen Watch Co. to create the WatchPad. It featured a 320x240 QVGA monochrome touch-sensitive display and it ran Linux


id: basque-museum-of-the-history-of-medicine-and-science-20260505-0
file: data/en.wikipedia.org/wiki/Basque_Museum_of_the_History_of_Medicine_and_Science-0.md
category: reference
title: Basque Museum of the History of Medicine and Science
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Basque_Museum_of_the_History_of_Medicine_and_Science
date_saved: 2026-05-05T09:32:27.636207+00:00
instance: kb-cron
parent: basque-museum-of-the-history-of-medicine-and-science-20260505-0
summary:
The Basque Museum of the History of Medicine (MHM, Basque: Medikuntza Historiaren Euskal Museoa, Spanish: Museo Vasco de Historia de la Medicina) was founded in 1982 to preserve and conserve the historic memory of medicine and scientific heritage of Basque Country. The Museum is located on the university campus of Leioa (University of the Basque Country) and is important in student training in the Faculty of Medicine and other faculties and schools. Its director is Anton Erkoreka. Its permanent exhibition comprises approximately 6,000 medical objects of the 19th and 20th centuries, thematically arranged in 24 rooms devoted to different medical specialties: folk medicine, unconventional medicine, pharmacy, weights and measures, asepsis and antisepsis, microscopes, laboratory material, X-rays, obstetrics and gynaecology, surgery, anesthesia, endoscope, odontology, cardiology, ophthalmology, electrotherapy, pathological anatomy and natural sciences. It also holds virtual exhibitions. Teaching and research constitute the two pillars of the Museum, complemented with publications, the organization of conferences, lectures, and other activities. == References == == External links == Basque Museum of the History of Medicine and Science The museum in the bulletin of the European Association of Museums of the History of Medical Sciences Virtual exhibition about electrotherapy Virtual exhibition about Stultifera navis. The


id: mus-e-curie-20260505-0
file: data/en.wikipedia.org/wiki/Musée_Curie-0.md
category: reference
title: Musée Curie
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Musée_Curie
date_saved: 2026-05-05T09:32:28.790847+00:00
instance: kb-cron
parent: mus-e-curie-20260505-0
summary:
The Musée Curie (French pronunciation: [myze kyʁi], Curie Museum) is a historical museum focusing on radiological research. It is located in the 5th arrondissement at 1, rue Pierre et Marie Curie, Paris, France, and open Wednesday to Saturday, from 1pm to 5pm; admission is free. The museum was renovated in 2012, thanks to a donation from Ève Curie. == History == In 1914, the laboratory was directed by Marie Curie. The museum was established in 1934, after Curie's death, on the ground floor of the Curie Pavilion of the Institut du Radium. It was formerly Marie Curie's laboratory, built 1911–1914, and where she performed research from 1914 to 1934. In this laboratory her daughter and son-in-law Irène and Frédéric Joliot-Curie discovered artificial radioactivity, for which they received the 1935 Nobel Prize for Chemistry. Irène Joliot-Curie died in 1956, Frédéric Joliot-Curie in 1958. The office and the laboratory are closed to be kept as a place of memory. In 1964, during the thirtieth anniversary of the discovery of artificial radioactivity, display cases were set up to present some of the devices used until the 1930s. In 1967, for the centenary of the birth of Marie Curie, her office and her personal


id: domus-galilaeana-20260505-0
file: data/en.wikipedia.org/wiki/Domus_Galilaeana-0.md
category: reference
title: Domus Galilaeana
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Domus_Galilaeana
date_saved: 2026-05-05T09:32:29.933385+00:00
instance: kb-cron
parent: domus-galilaeana-20260505-0
summary:
The Domus Galilaeana is a cultural and scientific institute and library, dedicated to the history of science, located in via Santa Maria #26, in Pisa, region of Tuscany, Italy. Currently, the Domus Galilaeana houses a library with more than 40,000 books and important files relating to scientists of the 20th century. == History == The idea of creating an institute dedicated to the Pisan scientist was born in 1938 in anticipation of the celebrations for the centenary of the First Meeting of Italian scientists held in Pisa in 1839. The institute’s formation was the initiative of Giovanni Gentile and sponsored by the Italian Society for the Progress of Sciences, and was established in Rome with a commission to identify goals and objectives of the new society, as well as the city and its location within the city. The choice fell on Pisa. The presentation was made in 1939 in the Aula Magna of the University of Pisa. The Domus Galilaeana received its legal status with the law of 1941. Since then, the establishment has collected all the ancient and modern publications on Galileo and coordinated studies in the history of science, thanks to a large archive and a major library.


id: mus-e-fragonard-d-alfort-20260505-0
file: data/en.wikipedia.org/wiki/Musée_Fragonard_d'Alfort-0.md
category: reference
title: Musée Fragonard d'Alfort
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Musée_Fragonard_d'Alfort
date_saved: 2026-05-05T09:32:31.077945+00:00
instance: kb-cron
parent: mus-e-fragonard-d-alfort-20260505-0
summary:
The Musée Fragonard d'Alfort, often simply the Musée Fragonard, is a museum of anatomical oddities located within the École Nationale Vétérinaire de Maisons-Alfort, 7 avenue du Général de Gaulle, in Maisons-Alfort, a suburb of Paris. It is open several days per week in the cooler months; an admission fee is charged. == Collections == The École Nationale Vétérinaire de Maisons-Alfort is one of the world's oldest veterinary schools, and the museum, created in 1766 with the school, is among France's oldest. The museum attracted incredible international attention since the school's founding and was a critical component of the school's identity in the eighteenth century. It opened to the public in 1991, and today consists of three rooms containing a large collection of anatomical oddities and dissections, most of which date from the 19th and early 20th centuries. In addition to animal skeletons and dissections, such as a piglet displayed in cross-section, the museum contains a substantial collection of monstrosities (teratology) including Siamese twin lambs, a two-headed calf, a 10-legged sheep, and a colt with one huge eye. The museum's most astonishing items are the famous "écorchés" (flayed figures) prepared by Honoré Fragonard, the school's first professor of anatomy, appointed in


id: mus-e-d-histoire-des-sciences-de-la-ville-de-gen-ve-20260505-0
file: data/en.wikipedia.org/wiki/Musée_d'histoire_des_sciences_de_la_Ville_de_Genève-0.md
category: reference
title: Musée d'histoire des sciences de la Ville de Genève
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Musée_d'histoire_des_sciences_de_la_Ville_de_Genève
date_saved: 2026-05-05T09:32:32.243804+00:00
instance: kb-cron
parent: mus-e-d-histoire-des-sciences-de-la-ville-de-gen-ve-20260505-0
summary:
The Musée d'histoire des sciences de la Ville de Genève (Museum of the History of Science of the City of Geneva) is a small museum in Switzerland dedicated to the history of science. == Location == The museum is located in the Villa Bartholoni, designed by Félix-Emmanuel Callet, built in 1830 as a summer residence for Parisian bankers, Constant and Jean-François Bartholoni and extensively restored between 1985 and 1992. It is situated in the park La Perle du Lac, overlooking Lake Geneva, adjacent to the Geneva Botanical Garden. Both the Villa and the museum itself are listed in the Swiss Inventory of Cultural Property of National and Regional Significance. == Access == The Museum is open daily from 10am to 5pm, except for 25 December and 1 January and admission is free. The museum receives over 250,000 visitors per year. == History == The museum was established in 1964 by the enthusiasm of l'Association du Musée et de la Revue d'histoire des sciences (the Museum and review of the History of Science Association), following an exhibition of science history at the Musée Rath. Once opened the Swiss Institute of Physics and Observatory donated their historic instruments to the collection. Early


id: history-of-science-museum-oxford-20260505-0
file: data/en.wikipedia.org/wiki/History_of_Science_Museum,_Oxford-0.md
category: reference
title: History of Science Museum, Oxford
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/History_of_Science_Museum,_Oxford
date_saved: 2026-05-05T09:32:33.426666+00:00
instance: kb-cron
parent: history-of-science-museum-oxford-20260505-0
summary:
The History of Science Museum in Broad Street, Oxford, England, holds a leading collection of scientific instruments from Middle Ages to the 19th century. The museum building is also known as the Old Ashmolean Building to distinguish it from the newer Ashmolean Museum building completed in 1894. The museum was built in 1683, and it is the world's oldest surviving purpose-built museum. == History == Built in 1683 to house Elias Ashmole's collection, the building was the world's first purpose-built museum building and was also open to the public. The original concept of the museum was to institutionalize the new learning about nature that appeared in the 17th century and experiments concerning natural philosophy were undertaken in a chemical laboratory in the basement, while lectures and demonstration took place in the School of Natural History, on the middle floor. Ashmole's collection was expanded to include a broad range of activities associated with the history of natural knowledge. In 1924, Lewis Evans donated his collection of historic scientific instruments, creating the Lewis Evans Collection. In 1935, with more donations, the museum's name was changed to the Museum of the History of Science. In 2018, the museum was renamed the History of


id: koninklijke-hollandsche-maatschappij-der-wetenschappen-20260505-0
file: data/en.wikipedia.org/wiki/Koninklijke_Hollandsche_Maatschappij_der_Wetenschappen-0.md
category: reference
title: Koninklijke Hollandsche Maatschappij der Wetenschappen
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Koninklijke_Hollandsche_Maatschappij_der_Wetenschappen
date_saved: 2026-05-05T09:32:34.624451+00:00
instance: kb-cron
parent: koninklijke-hollandsche-maatschappij-der-wetenschappen-20260505-0
summary:
The Koninklijke Hollandsche Maatschappij der Wetenschappen (Royal Holland Society of Sciences and Humanities), located on the east side of the Spaarne in downtown Haarlem, Netherlands, was established in 1752 and is the oldest society for the sciences in the country. The society has been housed in its present location, called Hodshon Huis, since 1841. Nearby the society is the Teylers Museum, a closely related museum of natural history founded in 1784. In 2002, the society was awarded the predicate "Royal" when it celebrated 250 years of science studies. == History of the society and museum == The society started as a gentleman's club that met in the Haarlem City Hall to discuss science topics and promote the study of the arts and sciences. They pooled resources to purchase books and specimens for study, which were kept in the town hall until they purchased a building on the Grote Houtstraat (nr. 51, since unrecognizably rebuilt), where the curator of the collection lived. Under the direction of Martin van Marum, a proper museum was established with zoological specimens located there on display for the public, as a forerunner of the modern Naturalis in Leiden. Van Marum also kept a small garden for


id: lisbon-astronomical-observatory-20260505-0
file: data/en.wikipedia.org/wiki/Lisbon_Astronomical_Observatory-0.md
category: reference
title: Lisbon Astronomical Observatory
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Lisbon_Astronomical_Observatory
date_saved: 2026-05-05T09:32:35.796263+00:00
instance: kb-cron
parent: lisbon-astronomical-observatory-20260505-0
summary:
The Lisbon Astronomical Observatory (Portuguese: Observatório Astronómico de Lisboa) is an astronomical observatory located in Tapada da Ajuda, in the civil parish of Alcântara, municipality of Lisbon. Recognized internationally for its quality of work in the field of positional astronomy (since the 19th century), in 1992, it became a dependency of the University of Lisbon (and later, part of the Faculty of Sciences), responsible for scientific and historical research, along with media relations. == History == From an 1812 map, there existed in the Alto da Casa Branca in the Tapada of Ajuda an older observatory. The observatory was born from great controversy between French astronomer Hervé Faye (1814-1902), then director of the Observatory of Paris, and Peters, an astronomer at the Russian Observatory of Pulkova, on the parallax of the star of Argelander. The construction of the Lisbon observatory was due to a strong desire to build an institution that was a reference in Portuguese culture. It was established in the mid-19th century with the aim of promoting new Sidereal Astronomy, discovery and understanding of the infinite cosmos, and concern about the exact mapping of the sky and measuring the size of the universe. In 1850, Hervé Faye and


id: lisbon-astronomical-observatory-20260505-1
file: data/en.wikipedia.org/wiki/Lisbon_Astronomical_Observatory-1.md
category: reference
title: Lisbon Astronomical Observatory
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Lisbon_Astronomical_Observatory
date_saved: 2026-05-05T09:32:35.796263+00:00
instance: kb-cron
parent: lisbon-astronomical-observatory-20260505-0
summary:
== Architecture == The Lisbon Astronomical Observatory consists of a central building in the hills of Ajuda and overlooking the Tejo river, and two small cupolas in the south containing instruments. Besides the central cupola there are three rooms for astronomical observations, equipped with instruments (the best for the time) and windows for observation. The central block of the observatory (a circular room) supports the weight of the large equatorial refractor over 8 large columns. In arches between the columns are many pendulum clock used over the century to measure the time. At the foot of the large windows (with a view over the Tapada da Ajuda) are wide tables, used by astronomers to assist in their research/investigation. In addition, there are spacious halls linking the central block, used for lessons, taking measurements and research, today used as workshops and support school educational activities. The three observation rooms are spacious and high, lined in wood, with open space between the wainscoting and the walls of masonry and roofing. This space communicates with the outside world through gaps that are constantly open. There are roofs of rooms in stacks of circulation, and this permanent ventilation is there in order to establish


id: mus-e-d-art-dentaire-pierre-fauchard-20260505-0
file: data/en.wikipedia.org/wiki/Musée_d'Art_Dentaire_Pierre_Fauchard-0.md
category: reference
title: Musée d'Art Dentaire Pierre Fauchard
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Musée_d'Art_Dentaire_Pierre_Fauchard
date_saved: 2026-05-05T09:32:36.985648+00:00
instance: kb-cron
parent: mus-e-d-art-dentaire-pierre-fauchard-20260505-0
summary:
The Musée d'Art Dentaire Pierre Fauchard (French pronunciation: [myze daʁ dɑ̃tɛʁ pjɛʁ foʃaʁ]) is a museum of dental history located in the 16th arrondissement at the Académie Nationale de Chirurgie Dentaire, 22 Rue Émile Ménier, Paris, France. It is open Wednesday afternoons by appointment. The nearest métro and RER stations are Porte Dauphine, Avenue Foch, and Victor Hugo. The museum dates to 1879, when Parisian dentists began to organize a dental school; with it the Musée d'Art Dentaire was established to display old techniques and tools. By 1892, its collection contained around 300 items. In 1937, the museum was renamed the Musée Pierre Fauchard to honor Pierre Fauchard (1678–1761), sometimes called the father of modern dentistry. Since 2003, its collections have been maintained by the Musée de l'Assistance Publique – Hôpitaux de Paris. Today the museum contains over 1,000 items relating to the history of dentistry, including instruments and dental chairs from the seventeenth century to nineteenth century, about 350 items for the cleaning and extraction of teeth, about 200 dental prosthetics, as well as etchings, paintings from the seventeenth century Dutch School, and a library of about 500 antique books including an original edition of Fauchard's "Le Chirurgien Dentiste",


id: mus-e-de-l-assistance-publique-h-pitaux-de-paris-20260505-0
file: data/en.wikipedia.org/wiki/Musée_de_l'Assistance_Publique_–_Hôpitaux_de_Paris-0.md
category: reference
title: Musée de l'Assistance Publique – Hôpitaux de Paris
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Musée_de_l'Assistance_Publique_–_Hôpitaux_de_Paris
date_saved: 2026-05-05T09:32:38.181158+00:00
instance: kb-cron
parent: mus-e-de-l-assistance-publique-h-pitaux-de-paris-20260505-0
summary:
The Musée de l'Assistance Publique – Hôpitaux de Paris (French pronunciation: [myze də lasistɑ̃s pyblik opito də paʁi], Museum of Public Assistance–Paris Hospitals) is a museum dedicated to the history of Parisian hospitals. It is located on the left bank of the Seine in the 5th arrondissement, at 47, quai de la Tournelle, Paris, France. The museum closed in 2012 and is evaluating reopening. The nearest Paris Métro station is Maubert-Mutualité on Line 10. The museum was housed in the Hôtel de Miramion, attributed to architect François Mansart, which was built as a private mansion for Christopher Martin in about 1630. The building became a Catholic school for girls from 1675 to 1794, then, during the First Empire, it was converted into the central pharmacy for hospitals in Paris, which operated from 1812 until 1974. The museum was established in 1934 by the municipal authority, Assistance Publique - Hôpitaux de Paris. The museum contained a broad collection of nearly 10,000 objects related to the history of Parisian hospitals from the Middle Ages to the present day. Objects held include French and Flemish paintings, furniture from the 17th and 18th centuries, a major collection of pharmaceutical faiences, textiles, and medical instruments.


id: mus-e-des-lunettes-et-lorgnettes-pierre-marly-20260505-0
file: data/en.wikipedia.org/wiki/Musée_des_Lunettes_et_Lorgnettes_Pierre_Marly-0.md
category: reference
title: Musée des Lunettes et Lorgnettes Pierre Marly
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Musée_des_Lunettes_et_Lorgnettes_Pierre_Marly
date_saved: 2026-05-05T09:32:39.307431+00:00
instance: kb-cron
parent: mus-e-des-lunettes-et-lorgnettes-pierre-marly-20260505-0
summary:
The Musée de la Lunette is a museum of eyeglasses located in Morez (Jura - Franche-Comté), France. It was formerly located in Paris, with the name Musée Pierre Marly - Lunettes et Lorgnettes. The museum was created by Pierre Marly, optician to crowned heads, public figures and celebrities. It contains almost 3,000 objects, ranging from spectacles dating from the 13th century to wooden Inuit snow goggles, with a permanent exhibition of lorgnettes, glasses, telescopes, and binoculars of all shapes and sizes. Items of interest include glasses made for cats and dogs, Maria Callas' contact lens, and glasses belonging to Princess Victoire of France (daughter of Louis XV), the Dalai Lama, Marlene Dietrich, Sammy Davis Jr., Elton John, and lorgnettes belonging to Sarah Bernhardt. == See also == Essilor – Scientific and technical heritage == References == Kristan Lawson and Anneli S. Rufus, Weird Europe: A Guide to Bizarre, Macabre, and Just Plain Weird Sights, Macmillan, 1999, page 67. ISBN 0-312-19873-6.


id: museo-galileo-20260505-0
file: data/en.wikipedia.org/wiki/Museo_Galileo-0.md
category: reference
title: Museo Galileo
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Museo_Galileo
date_saved: 2026-05-05T09:32:40.461113+00:00
instance: kb-cron
parent: museo-galileo-20260505-0
summary:
Museo Galileo (formerly Istituto e Museo di Storia della Scienza; Institute and Museum of the History of Science) is located in Florence, Italy, in Piazza dei Giudici, along the River Arno and close to the Uffizi Gallery. The museum, dedicated to astronomer and scientist Galileo Galilei, is housed in Palazzo Castellani, an 11th-century building which was then known as the Castello d'Altafronte. Museo Galileo owns one of the world's major collection of scientific instruments, which bears evidence of the role that the Medici and Lorraine Grand Dukes attached to science and scientists. The Museo di Storia della Scienza re-opened to the public with the new name Museo Galileo in June 2010, after a two-year closure due to redesigning and renovation work. Its name change celebrates the 400-year anniversary of Galileo's Sidereus Nuncius (The Starry Messenger), first published in March of 1610. == The museum == The museum features the valuable scientific instruments from the Medici Collections which were first displayed in the Stanzino delle Matematiche (Mathematics Room) in the Uffizi Gallery. They were later moved to the Museo di Fisica e Storia Naturale (Museum of Physics and Natural History) founded by Grand Duke Peter Leopold in 1775. During the reign


id: museo-galileo-20260505-1
file: data/en.wikipedia.org/wiki/Museo_Galileo-1.md
category: reference
title: Museo Galileo
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Museo_Galileo
date_saved: 2026-05-05T09:32:40.461113+00:00
instance: kb-cron
parent: museo-galileo-20260505-0
summary:
== The library == The library, which has been a part of the institute since its foundation, was completely remodelled in 2002, when it was moved to the third floor of Palazzo Castellani. The new architectural display was awarded the “Bibliocom Biblioteche in vetrina” prize. The library houses about 150,000 works concerning the history of science. The antique book collection consists of nearly 5,000 works. It includes the Medici-Lorraine Collection, comprising scientific books mostly about physics and mathematics, gathered by Tuscan dynasties over five centuries. The library is also home to several 18th- to 20th-century archival collections and a photo archive related to the history of the museum's collections, ancient instruments and places of scientific interest. The contemporary collection includes books in Italian and the major European languages and has an annual growth of about 1,800 new acquisitions. All of the library's material can be searched in the online catalogue. Among the library's activities are the compiling of bibliographies –notably the International Galilaean Bibliography– and the cataloguing of documents relevant to the history of science, even those not in the library's possession. In 2004, a Digital Library was created to preserve and publish digital collections of historical scientific interest. ==


id: nikola-tesla-memorial-center-20260505-0
file: data/en.wikipedia.org/wiki/Nikola_Tesla_Memorial_Center-0.md
category: reference
title: Nikola Tesla Memorial Center
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Nikola_Tesla_Memorial_Center
date_saved: 2026-05-05T09:32:41.637392+00:00
instance: kb-cron
parent: nikola-tesla-memorial-center-20260505-0
summary:
The Nikola Tesla Memorial Center (Croatian: Memorijalni centar Nikola Tesla) is a cultural-historical site and museum located in Smiljan, Croatia, located at the birthplace of Nikola Tesla, one of the world's foremost engineers and inventors. It is dedicated to Tesla, who was born in 1856 in his Serb parents house in Smiljan, then part of the Kingdom of Croatia within the Austrian Empire. The young engineer later left his homeland to work in America. The Lika Museum in nearby Gospić administers the site. == History == The Memorial Center was opened to the public on the 150th anniversary of Tesla's birthday, 10 July 2006, by the President of the Republic of Croatia. The original memorial site was first established as a museum in 1956, but it was damaged during the Croatian War of Independence when a projectile fell on the commercial building next to Nikola Tesla's house. The fire was eventually put out by the Croatian Army who deposited furniture and other objects it saved in the Museum of Lika. The Croatian authorities restored the complex and reopened it in a 2006 ceremony, with the highest dignitaries of Croatia and Serbia attending. After the war it was renovated, improved, equipped


id: pharmacy-museum-of-the-university-of-basel-20260505-0
file: data/en.wikipedia.org/wiki/Pharmacy_Museum_of_the_University_of_Basel-0.md
category: reference
title: Pharmacy Museum of the University of Basel
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Pharmacy_Museum_of_the_University_of_Basel
date_saved: 2026-05-05T09:32:44.027325+00:00
instance: kb-cron
parent: pharmacy-museum-of-the-university-of-basel-20260505-0
summary:
The Pharmacy Museum of the University of Basel (Pharmaziemuseum der Universität Basel, formerly Pharmazie-Historisches Museum der Universität Basel, originally Sammlung für das historische Apothekenwesen) shows in its permanent collection the history of medicinal remedies and their preparation. Designed as a collection of specimens for study purposes, the museum was founded in 1924 by Josef Anton Häfliger (1873–1954) and has been preserved to this day in its original form as a 'scientific cabinet'. The museum is one of the largest and most significant collections of pharmaceutical objects and the history of pharmacy. It contains pharmaceutical ceramics, complete fixtures and fittings from historical pharmacies, an alchemical laboratory, mortars, historical first aid kits, books, medications used in the past, and everything related to the preparation of medicinal remedies. == History == »Zum Vorderen Sessel«, the building that houses the museum, is located in the historic centre of Basel, halfway between the market square and St Peter's Church. First mentioned in 1316 as the »Unter Krämern« bathhouse, it is rich in history. From 1480, the renowned printer Johannes Amerbach lived there; he was the ancestor of the famous academic Amerbach family. In 1507, the house was acquired by Johannes Frobenius, probably the most famous


id: pharmacy-museum-of-the-university-of-basel-20260505-1
file: data/en.wikipedia.org/wiki/Pharmacy_Museum_of_the_University_of_Basel-1.md
category: reference
title: Pharmacy Museum of the University of Basel
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Pharmacy_Museum_of_the_University_of_Basel
date_saved: 2026-05-05T09:32:44.027325+00:00
instance: kb-cron
parent: pharmacy-museum-of-the-university-of-basel-20260505-0
summary:
== See also == Museums in Basel List of museums in Switzerland == Literature (in German) == Häfliger, Josef Anton: Pharmazeutische Altertumskunde und die Schweizerische Sammlung für historisches Apothekenwesen an der Universität Basel. Zurich 1931. Häfliger, Josef Anton: Das Apothekenwesen Basels. Basel 1938. Lutz, Alfons: Josef Anton Häfliger, der Begründer der pharmazeutischen Altertumskunde (1873-1954). In: Basler Jahrbuch 1956, S. 125–129. Lutz, Alfons, und Mez-Mangold, Lydia: Schweizerisches Pharmazie-Historisches Museum in Basel. Bern 1968 and 1974. Mez-Mangold Lydia: Aus der Geschichte des Medikaments. Basel 1972. Olonetzky, Beny, und Mez-Mangold, Lydia: Die Sammlung: Darstellung alter Arztinstrumente, Apotheker-Gefässe, Mikroskope, Einnehmelöffel, Terra sigillata, Amulette […]. Stuttgart 1980. Kessler, Michael, und Mez-Mangold, Lydia: Womit der Apotheker einst hantierte. Basel 1975 and 1990. Gugger, Beat, und Kessler, Michael: Revolution: Apothekerkunst und Industrieprozess. Basel 1996. Kessler, Michael, et al.: Strömung, Kraft und Nebenwirkung; Eine Geschichte der Basler Pharmazie. Basel 2002. Kessler, Michael, et al.: Leben am Totengässlein. Das Pharmazie-Historische Museum Basel im Haus "Zum Sessel". Basel 2002 and 2015. Kluge, Martin: Mit Kräutersud und Gottvertrauen. Basel 2008. == In-house publications (in German) == Kluge, Martin: Drachen in der Medizin. Reale Arznei aus irrealen Wesen. Exhibition catalogue; Basel 2005. Häner, Flavio, und Kessler, Michael: Lust, Leid und Wissen. Eine


id: polytechnic-museum-20260505-0
file: data/en.wikipedia.org/wiki/Polytechnic_Museum-0.md
category: reference
title: Polytechnic Museum
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Polytechnic_Museum
date_saved: 2026-05-05T09:32:45.213458+00:00
instance: kb-cron
parent: polytechnic-museum-20260505-0
summary:
The Polytechnic Museum (Russian: Политехнический музей) is one of the oldest science museums in the world and is located in Moscow. It showcases Russian and Soviet technology and science, as well as modern inventions. It was founded in 1872 after the first All-Russian Technical Exhibition on the bicentennial anniversary of the birth of Peter the Great at the initiative of the Society of Devotees of Natural Science, Anthropology, and Ethnography. The first stage of the museum was designed by Ippolit Monighetti and completed in 1877. The north wing was added in 1896 and the south wing in 1907. The Polytechnic Museum is the largest technical museum in Russia, and houses a wide range of historical inventions and technological achievements, including humanoid automata of the 18th century, and the first Soviet computers. The collection contains over 160,000 items in 65 halls including, chemistry, mining, metallurgy, transport, energy, optics, automation, computer engineering, radio electronics, communications, and space exploration. Highlights include the first achromatic telescope; an early solar microscope by German anatomists Johann Nathanael Lieberkühn; an early seismograph by Boris Borisovich Galitzine; galvanoplastics by Moritz von Jacobi; and early electric lights by Pavel Yablochkov. == History == The Society of Devotees of Natural


id: science-history-institute-20260505-0
file: data/en.wikipedia.org/wiki/Science_History_Institute-0.md
category: reference
title: Science History Institute
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Science_History_Institute
date_saved: 2026-05-05T09:32:46.362005+00:00
instance: kb-cron
parent: science-history-institute-20260505-0
summary:
The Science History Institute is an institution that preserves and promotes understanding of the history of science. Located in Philadelphia, Pennsylvania, it includes a library, museum, archive, research center and conference center. It was founded in 1982 as a joint venture of the American Chemical Society and the University of Pennsylvania, as the Center for the History of Chemistry (CHOC). The American Institute of Chemical Engineers (AIChE) became a co-founder in 1984. It was renamed the Chemical Heritage Foundation (CHF) in 1992, and moved two years later to the institution's current location, 315 Chestnut Street in Old City. On December 1, 2015, CHF merged with the Life Sciences Foundation, creating an organization that covers "the history of the life sciences and biotechnology together with the history of the chemical sciences and engineering." As of February 1, 2018, the organization was renamed the Science History Institute, to reflect its wider range of historical interests, from chemical sciences and engineering to the life sciences and biotechnology. The institute focuses on the history of chemistry, the history of science, the history of technology, trends in research and development, the impact of science on society, and relationships between science and art. It supports a


id: science-history-institute-20260505-1
file: data/en.wikipedia.org/wiki/Science_History_Institute-1.md
category: reference
title: Science History Institute
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Science_History_Institute
date_saved: 2026-05-05T09:32:46.362005+00:00
instance: kb-cron
parent: science-history-institute-20260505-0
summary:
==== Othmer Library of Chemical History ==== In 1989, the center received a further challenge grant, this time from Donald F. Othmer and his wife, Mildred Topp Othmer. Donald Othmer was a quiet chemical engineering professor from Polytechnic University in Brooklyn. The Othmers donated $5 million towards the creation of the Othmer Library of Chemical History. Again, efforts to match the grant were supported by the National Foundation for History of Chemistry and the American Chemical Society's Campaign for Chemistry. The new library was further supported by the donation of 8,500 monographs, textbooks and reference works from The Chemists' Club of New York. === Chemical Heritage Foundation === On July 1, 1992, the National Foundation for History of Chemistry changed its name to the Chemical Heritage Foundation, in recognition of the international nature of chemical history. By 1994, the organization was searching for a permanent home for the Beckman Center and Othmer Library. One candidate was the First National Bank building at 315 Chestnut Street, an 1866 masonry-and-brick structure with a two-story Palazzo facade. The institution bought the bank building and nearby property in 1995, in part with a matching grant from Donald Othmer. Soon afterward, its endowment was expanded


id: science-history-institute-20260505-2
file: data/en.wikipedia.org/wiki/Science_History_Institute-2.md
category: reference
title: Science History Institute
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Science_History_Institute
date_saved: 2026-05-05T09:32:46.362005+00:00
instance: kb-cron
parent: science-history-institute-20260505-0
summary:
As early as 1996, the Chemical Heritage Foundation had envisioned a broadly-based museum of chemical progress in which instruments would have "a major, but not exclusive role". That vision was followed when Peter Saylor of Dagit•Saylor Architects created the public museum and conference space. The Arnold O. Beckman Permanent Exhibit and the Clifford C. Hach Gallery for rotating exhibitions opened in 2008. The Arnold O. Beckman permanent exhibition, Making Modernity, was designed by Ralph Appelbaum Associates. It has been described as an "art gallery for science", and showcases objects from the institution's widely varying collections. "The instruments are only a fraction of the objects on display. The exhibition also includes books, documents, and artwork from CHF's collection, as well as an array of consumer products." The exhibition is organized around thematic arcs illustrative of the history of science, particularly chemistry. Displays include the influence of alchemy in early chemistry, the development of the first plastics, the development of brilliantly colored synthetic dyes, scientific advocacy for public health in the 19th and 20th centuries, and the teaching of chemistry through books and chemistry sets. === Science History Institute === On December 1, 2015, the Chemical Heritage Foundation merged with the Life


id: science-history-institute-20260505-3
file: data/en.wikipedia.org/wiki/Science_History_Institute-3.md
category: reference
title: Science History Institute
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Science_History_Institute
date_saved: 2026-05-05T09:32:46.362005+00:00
instance: kb-cron
parent: science-history-institute-20260505-0
summary:
== Distillations == The Science History Institute's magazine, Distillations, appeared in print three times a year until 2019, when content became digital-only. As an online resource, it continues to present stories about the history of science for a popular readership. Distillations first appeared in spring 2015, as a publication of the Chemical Heritage Foundation. It was predated by the Chemical Heritage Magazine, published as a quarterly by the Chemical Heritage Foundation. == Fellowships == The Science History Institute offers many fellowships-in-residence, of varying lengths. == Awards == The Science History Institute presents a number of annual awards to recognize outstanding contributions to science and technology by researchers, business leaders and entrepreneurs. The annual Heritage Day Awards honor achievements in science and technology and comprise the Othmer Gold Medal, the Richard J. Bolte Sr. Award for Supporting Industries and, in conjunction with The Chemists' Club of New York, the Winthrop-Sears Medal. The annual Affiliate Partnership Awards, presented in conjunction with affiliate organizations, recognize achievement with the Biotechnology Heritage Award, the Franklin-Lavoisier Prize, the Petrochemical Heritage Award and the Pittcon Heritage Award. The Roy G. Neville Prize in Bibliography or Biography recognizes a biographical work in the field of chemical or molecular


id: teylers-museum-20260505-0
file: data/en.wikipedia.org/wiki/Teylers_Museum-0.md
category: reference
title: Teylers Museum
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Teylers_Museum
date_saved: 2026-05-05T09:32:47.568078+00:00
instance: kb-cron
parent: teylers-museum-20260505-0
summary:
Teylers Museum (Dutch pronunciation: [ˈtɛilərs myˈzeːjʏm]) is an art, natural history, and science museum in Haarlem, Netherlands. Established in 1778, Teylers Museum was founded as a centre for contemporary art and science. The historic centre of the museum is the neoclassical Oval Room (1784), which was built behind the house of Pieter Teyler van der Hulst (1702–1778), the so-called Fundatiehuis (Foundation House). Pieter Teyler was a wealthy cloth merchant and banker of Scottish descent, who bequeathed his fortune for the advancement of religion, art, and science. He was a Mennonite and follower of the Scottish Enlightenment. == History == In his will, Pieter Teyler stipulated that his collection and part of his fortune should be used to establish a foundation for their promotion: Teylers Stichting. The Teyler legacy to the city of Haarlem was split into two societies: Teylers First or Theological Society (Dutch: Teylers Eerste of Godgeleerd Genootschap), intended for the study of religion and Teylers Second Society (Dutch: Teylers Tweede Genootschap), which was to concern itself with physics, poetry, history, drawing, and numismatics. The executors of Teyler's will, the first directors of Teylers Stichting, decided to establish a centre for study and education. Under a single roof, it


id: teylers-museum-20260505-1
file: data/en.wikipedia.org/wiki/Teylers_Museum-1.md
category: reference
title: Teylers Museum
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Teylers_Museum
date_saved: 2026-05-05T09:32:47.568078+00:00
instance: kb-cron
parent: teylers-museum-20260505-0
summary:
== Heritage site == The museum is on the top 100 Dutch heritage sites list compiled by the Department for Conservation in 1990. It was nominated on 12 December 2011 by the Dutch Cabinet for UNESCO World Heritage Site status, based on its long history as a public knowledge institute and its continued efforts to preserve public access to its collections. However, the nomination was withdrawn in 2013. == Administration == Since 1 January 2022, Marc de Beyer is the museum director. The former director is Marjan Scharloo. Terry van Druten is curator of the art collections of the museum, Trienke van der Spek is curator of the scientific collections, including fossils, minerals and the library. The museum had 137,000 visitors in 2019. Teylers Museum is a member of the Museumvereniging (Museum Association). == See also == Teylers Hofje – related site Jaap van der Veen/Teylers Museum Prize for the Contemporary Art Medal - prize Tiberius Cornelis Winkler – curator Hendrik Jacobus Scholten – curator Gerrit Jan Michaëlis – curator Vincent Jansz van der Vinne – first caretaker Highgrove Florilegium – book in the collection == References == == Further reading == M. Scharloo (ed.), Teylers Museum: A Journey in


id: whipple-museum-of-the-history-of-science-20260505-0
file: data/en.wikipedia.org/wiki/Whipple_Museum_of_the_History_of_Science-0.md
category: reference
title: Whipple Museum of the History of Science
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Whipple_Museum_of_the_History_of_Science
date_saved: 2026-05-05T09:32:48.732198+00:00
instance: kb-cron
parent: whipple-museum-of-the-history-of-science-20260505-0
summary:
The Whipple Museum of the History of Science is a museum attached to the University of Cambridge, England, which houses an extensive collection of scientific instruments, apparatus, models, pictures, prints, photographs, books and other material related to the history of science. It is located in the former Perse School on Free School Lane, Cambridge. The museum was founded in 1944, when Robert Whipple presented his collection of scientific instruments to the University of Cambridge. The museum's collection was 'designated' by the Museums, Libraries and Archives Council (MLA) as being of "national and international importance". The museum is one of eight museums in the University of Cambridge Museums consortium. == Department of History and Philosophy of Science == The museum forms part of the Department of History and Philosophy of Science, University of Cambridge. The department includes a working library with a large collection of early scientific books, some of which were given by Robert Whipple, chairman of the Cambridge Scientific Instrument Company. The museum plays an important part in the department's teaching and research. == Collections == The museum's holdings are particularly strong in material dating from the 17th to the 19th centuries, especially objects produced by English instrument makers,


id: natural-philosophy-20260505-0
file: data/en.wikipedia.org/wiki/Natural_philosophy-0.md
category: reference
title: Natural philosophy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Natural_philosophy
date_saved: 2026-05-05T09:32:50.253479+00:00
instance: kb-cron
parent: natural-philosophy-20260505-0
summary:
Natural philosophy, philosophy of nature (from Latin philosophia naturalis), or experimental philosophy, until the late modern period, was the systematic and research-based study of nature and the physical universe, while ignoring any supernatural influence. Used since at least Aristotle (classical antiquity) until the 19th century, the term natural philosophy referred to a branch of philosophy—a broader term then, meaning all rational fields of study and contemplation—that explored topics now considered to fall under the purview of science, such as physics, biology, chemistry, and astronomy. Thus, natural philosophy served as the precursor to, and has been mostly supplanted by, modern science. The 19th century established the term science as distinct from philosophy in its rigorously empirical and experimental approach, along with its many modern sub-disciplines, plus the founding of various institutions and communities devoted to them. Isaac Newton's book Philosophiæ Naturalis Principia Mathematica (1687) (English: Mathematical Principles of Natural Philosophy) reflects the use of the term natural philosophy in the 17th century. Even in the 19th century, the work that helped define much of modern physics bore the title Treatise on Natural Philosophy (1867), authored by Lord Kelvin and Tait. In the German tradition, Naturphilosophie (philosophy of nature) persisted into the


id: natural-philosophy-20260505-1
file: data/en.wikipedia.org/wiki/Natural_philosophy-1.md
category: reference
title: Natural philosophy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Natural_philosophy
date_saved: 2026-05-05T09:32:50.253479+00:00
instance: kb-cron
parent: natural-philosophy-20260505-0
summary:
Humankind's mental engagement with nature certainly predates civilization and the record of history. Philosophical, and specifically non-religious, thought about the natural world goes back to ancient Greece. These lines of thought began before Socrates, who turned his philosophical studies from speculations about nature to a consideration of man, or in other words, political philosophy. The thought of early philosophers such as Parmenides, Heraclitus, and Democritus centered on the natural world. In addition, three Presocratic philosophers who lived in the Ionian town of Miletus (hence the Milesian School of philosophy), Thales, Anaximander, and Anaximenes, attempted to explain natural phenomena without recourse to creation myths involving the Greek gods. They were called the physikoi ("natural philosophers") or, as Aristotle referred to them, the physiologoi. Plato followed Socrates in concentrating on man. It was Plato's student, Aristotle, who, in basing his thought on the natural world, returned empiricism to its primary place, while leaving room in the world for man. Martin Heidegger observes that Aristotle was the originator of conception of nature that prevailed in the Middle Ages into the modern era: The Physics is a lecture in which he seeks to determine beings that arise on their own, τὰ φύσει ὄντα (ta


id: natural-philosophy-20260505-2
file: data/en.wikipedia.org/wiki/Natural_philosophy-2.md
category: reference
title: Natural philosophy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Natural_philosophy
date_saved: 2026-05-05T09:32:50.253479+00:00
instance: kb-cron
parent: natural-philosophy-20260505-0
summary:
=== In ancient Greece === Early Greek philosophers studied motion and the cosmos. Figures like Hesiod regarded the natural world as offspring of the gods, whereas others like Leucippus and Democritus regarded the world as lifeless atoms in a vortex. Anaximander deduced that eclipses happen because of apertures in rings of celestial fire. Heraclitus believed that the heavenly bodies were made of fire that were contained within bowls. He thought that eclipses happen when the bowl turned away from the earth. Anaximenes is believed to have stated that an underlying element was air, and by manipulating air someone could change its thickness to create fire, water, dirt, and stones. Empedocles identified the elements that make up the world, which he termed the roots of all things, as fire, air, earth, and water. Parmenides argued that all change is a logical impossibility. He gives the example that nothing can go from nonexistence to existence. Plato argues that the world is an imperfect replica of an idea that a divine craftsman once held. He also believed that the only way to truly know something was through reason and logic. Not the study of the object itself, but that changeable matter is a


id: natural-philosophy-20260505-3
file: data/en.wikipedia.org/wiki/Natural_philosophy-3.md
category: reference
title: Natural philosophy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Natural_philosophy
date_saved: 2026-05-05T09:32:50.253479+00:00
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parent: natural-philosophy-20260505-0
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=== Natural philosophy in the early modern period === The scientific method has ancient precedents, and Galileo exemplifies a mathematical understanding of nature, which is a hallmark of modern natural scientists. Galileo proposed that objects falling regardless of their mass would fall at the same rate, as long as the medium they fall in is identical. The 19th-century distinction of a scientific enterprise apart from traditional natural philosophy has its roots in prior centuries. Proposals for a more "inquisitive" and practical approach to the study of nature are notable in Francis Bacon, whose ardent convictions did much to popularize his insightful Baconian method. The Baconian method is employed throughout Thomas Browne's encyclopaedia Pseudodoxia Epidemica (1646–1672), which debunks a wide range of common fallacies through empirical investigation of nature. The late-17th-century natural philosopher Robert Boyle wrote a seminal work on the distinction between physics and metaphysics called, A Free Enquiry into the Vulgarly Received Notion of Nature, as well as The Skeptical Chymist, after which the modern science of chemistry is named, (as distinct from proto-scientific studies of alchemy). These works of natural philosophy are representative of a departure from the medieval scholasticism taught in European universities, and anticipate in many


id: natural-philosophy-20260505-4
file: data/en.wikipedia.org/wiki/Natural_philosophy-4.md
category: reference
title: Natural philosophy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Natural_philosophy
date_saved: 2026-05-05T09:32:50.253479+00:00
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parent: natural-philosophy-20260505-0
summary:
Environmental philosophy – Branch of philosophy Gentleman scientist – Financially independent scientistPages displaying short descriptions of redirect targets History of science Natural environment – Living and non-living things on Earth Natural theology – Theology reliant on rational and empirical arguments Naturalism (philosophy) – Belief that only natural laws and forces operate in the universe Nature (philosophy) – Philosophical term Protoscience – Research field that may become a science == References == == Further reading == Adler, Mortimer J. (1993). The Four Dimensions of Philosophy: Metaphysical, Moral, Objective, Categorical. Macmillan. ISBN 0-02-500574-X. E.A. Burtt, Metaphysical Foundations of Modern Science (Garden City, NY: Doubleday and Company, 1954). Philip Kitcher, Science, Truth, and Democracy. Oxford Studies in Philosophy of Science. Oxford; New York: Oxford University Press, 2001. LCCN:2001036144 ISBN 0-19-514583-6 Bertrand Russell, A History of Western Philosophy and Its Connection with Political and Social Circumstances from the Earliest Times to the Present Day (1945) Simon & Schuster, 1972. Santayana, George (1923). Scepticism and Animal Faith. Dover Publications. pp. 27–41. ISBN 0-486-20236-4. {{cite book}}: ISBN / Date incompatibility (help) David Snoke, Natural Philosophy: A Survey of Physics and Western Thought. Access Research Network, 2003. ISBN 1-931796-25-4.Natural Philosophy: A Survey of Physics and Western Thought


id: alchemy-20260505-0
file: data/en.wikipedia.org/wiki/Alchemy-0.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
Alchemy (from the Arabic word al-kīmīā, الكیمیاء) is an ancient branch of natural philosophy, a philosophical and protoscientific tradition that was historically practised in China, India, the Muslim world, and Europe. In its Western form, alchemy is first attested in a number of pseudepigraphical texts written in Greco-Roman Egypt during the first few centuries AD. Greek-speaking alchemists often referred to their craft as "the Art" (τέχνη) or "Knowledge" (ἐπιστήμη), and it was often characterised as mystic (μυστική), sacred (ἱɛρά), or divine (θɛíα). Alchemists attempted to purify, mature, and perfect certain materials. Common aims were chrysopoeia, the transmutation of "base metals" (e.g., lead) into "noble metals" (particularly gold); the creation of an elixir of immortality; and the creation of panaceas able to cure any disease. The perfection of the human body and soul was thought to result from the alchemical magnum opus ("Great Work"). The concept of creating the philosopher's stone was variously connected with all of these projects. Islamic and European alchemists developed a basic set of laboratory techniques, theories, and terms, some of which are still in use today. They did not abandon the Ancient Greek philosophical idea that everything is composed of four elements, and they tended to


id: alchemy-20260505-1
file: data/en.wikipedia.org/wiki/Alchemy-1.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
The start of Western alchemy may generally be traced to Hellenistic Egypt, where the city of Alexandria was a center of alchemical knowledge, and retained its pre-eminence through most of the Greek and Roman periods. Following the work of André-Jean Festugière, modern scholars see alchemical practice in the Roman Empire as originating from the Egyptian goldsmith's art, Greek philosophy and different religious traditions. Tracing the origins of the alchemical art in Egypt is complicated by the pseudepigraphic nature of texts from the Greek alchemical corpus. The treatises of Zosimos of Panopolis, the earliest historically attested author (fl. c. 300), can help in situating the other authors. Zosimus based his work on that of older alchemical authors, such as Mary the Jewess, Pseudo-Democritus, and Agathodaimon, but very little is known about any of these authors. The most complete of their works, the Four Books of Pseudo-Democritus, were probably written in the first century AD. Recent scholarship tends to emphasize the testimony of Zosimus, who traced the alchemical arts back to Egyptian metallurgical and ceremonial practices. It has also been argued that early alchemical writers borrowed the vocabulary of Greek philosophical schools but did not implement any of its doctrines in a


id: alchemy-20260505-2
file: data/en.wikipedia.org/wiki/Alchemy-2.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
True alchemy never regarded earth, air, water, and fire as corporeal or chemical substances in the present-day sense of the word. The four elements are simply the primary, and most general, qualities by means of which the amorphous and purely quantitative substance of all bodies first reveals itself in differentiated form." Later alchemists extensively developed the mystical aspects of this concept. Alchemy coexisted alongside emerging Christianity. Lactantius believed Hermes Trismegistus had prophesied its birth. Augustine of Hippo later affirmed this in the 4th and 5th centuries, but also condemned Trismegistus for idolatry. Examples of pagan, Christian, and Jewish alchemists can be found during this period. Most of the Greco-Roman alchemists preceding Zosimos are known only by pseudonyms, such as Moses of Alexandria, Isis, Cleopatra the Alchemist, Pseudo-Democritus, and Ostanes. Other authors such as Komarios and Chymes are known only through surviving fragments of text. After AD 400, Greek alchemical writers occupied themselves solely in commenting on the works of these predecessors. By the middle of the 7th century, alchemy was almost an entirely mystical discipline. It was at that time that Khalid Ibn Yazid sparked its migration from Alexandria to the Islamic world, facilitating the translation and preservation of Greek


id: alchemy-20260505-3
file: data/en.wikipedia.org/wiki/Alchemy-3.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
To form an idea of the historical place of Jabir's alchemy and to tackle the problem of its sources, it is advisable to compare it with what remains to us of the alchemical literature in the Greek language. One knows in which miserable state this literature reached us. Collected by Byzantine scientists from the tenth century, the corpus of the Greek alchemists is a cluster of incoherent fragments, going back to all the times since the third century until the end of the Middle Ages. The efforts of Berthelot and Ruelle to put a little order in this mass of literature led only to poor results, and the later researchers, among them in particular Mrs. Hammer-Jensen, Tannery, Lagercrantz, von Lippmann, Reitzenstein, Ruska, Bidez, Festugière and others, could make clear only few points of detail .... The study of the Greek alchemists is not very encouraging. An even surface examination of the Greek texts shows that a very small part only was organized according to true experiments of laboratory: even the supposedly technical writings, in the state where we find them today, are unintelligible nonsense which refuses any interpretation. It is different with Jabir's alchemy. The relatively clear description of the


id: alchemy-20260505-4
file: data/en.wikipedia.org/wiki/Alchemy-4.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
Whereas European alchemy eventually centered on the transmutation of base metals into noble metals, Chinese alchemy had a more obvious connection to medicine. The philosopher's stone of European alchemists can be compared to the elixir of life sought by Chinese alchemists. In the Hermetic view, these two goals were not unconnected, and the philosopher's stone was often equated with the universal panacea; therefore, the two traditions may have had more in common than initially appears. As early as 317 AD, Ge Hong documented the use of metals, minerals, and elixirs in early Chinese medicine. Hong identified three ancient Chinese documents—titled the Scripture of Great Clarity, the Scripture of the Nine Elixirs, and the Scripture of the Golden Liquor—as texts containing fundamental alchemical information. He also described alchemy, along with meditation, as the sole spiritual practices that could allow one to gain immortality or to transcend to a higher state of being. In his work Inner Chapters of the Book of the Master Who Embraces Spontaneous Nature (317 AD), Hong argued that alchemical solutions such as elixirs were preferable to traditional medicinal treatment due to the spiritual protection they could provide. In the centuries following Ge Hong's death, the emphasis placed


id: alchemy-20260505-5
file: data/en.wikipedia.org/wiki/Alchemy-5.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
The introduction of alchemy to Latin Europe may be dated to 11 February 1144, with the completion of Robert of Chester's translation of the Liber de compositione alchemiae (Book on the Composition of Alchemy) from an Arabic work attributed to Khalid ibn Yazid. Although European craftsmen and technicians pre-existed, Robert notes in his preface that alchemy (here still referring to the elixir rather than to the art itself) was unknown in Latin Europe at the time of his writing. The translation of Arabic texts concerning numerous disciplines including alchemy flourished in 12th-century Toledo, Spain, through contributors like Gerard of Cremona and Adelard of Bath. Translations of the time included the Turba Philosophorum, and the works of Avicenna and Muhammad ibn Zakariya al-Razi. These brought with them many new words to the European vocabulary for which there was no previous Latin equivalent. Alcohol, carboy, elixir, and athanor are examples. Meanwhile, theologian contemporaries of the translators made strides towards the reconciliation of faith and experimental rationalism, thereby priming Europe for the influx of alchemical thought. The 11th-century theologian Anselm of Canterbury put forth the opinion that faith and rationalism were compatible and encouraged rationalism in a Christian context. In the early 12th


id: alchemy-20260505-6
file: data/en.wikipedia.org/wiki/Alchemy-6.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
In the 14th century, alchemy became more accessible to Europeans outside the confines of Latin-speaking churchmen and scholars. Alchemical discourse shifted from scholarly philosophical debate to an exposed social commentary on the alchemists themselves. Dante, Piers Plowman, and Chaucer all painted unflattering pictures of alchemists as thieves and liars. Pope John XXII's 1317 edict Spondent quas non-exhibent forbade the false promises of transmutation made by pseudo-alchemists. Roman Catholic Inquisitor General Nicholas Eymerich's Directorium Inquisitorum, written in 1376, associated alchemy with the performance of demonic rituals, which Eymerich differentiated from magic performed in accordance with Christian scripture. This did not, however, lead to any change in the Inquisition's monitoring or prosecution of alchemists. In 1404, Henry IV of England banned the practice of multiplying metals by the passing of the Gold and Silver Act 1403 (5 Hen. 4. c. 4) (although it was possible to buy a licence to attempt to make gold alchemically, and a number were granted by Henry VI and Edward IV). These critiques and regulations centered more around pseudo-alchemical charlatanism than the actual study of alchemy, which continued with an increasingly Christian tone. The 14th century saw the Christian imagery of death and resurrection employed in the


id: alchemy-20260505-7
file: data/en.wikipedia.org/wiki/Alchemy-7.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
Although most of these appointments were legitimate, the trend of pseudo-alchemical fraud continued through the Renaissance. Betrüger would use sleight of hand, or claims of secret knowledge to make money or secure patronage. Legitimate mystical and medical alchemists such as Michael Maier and Heinrich Khunrath wrote about fraudulent transmutations, distinguishing themselves from the con artists. False alchemists were sometimes prosecuted for fraud. The terms "chemia" and "alchemia" were used as synonyms in the early modern period, and the differences between alchemy, chemistry and small-scale assaying and metallurgy were not as neat as in the present day. There were important overlaps between practitioners, and trying to classify them into alchemists, chemists and craftsmen is anachronistic. For example, Tycho Brahe (1546–1601), an alchemist better known for his astronomical and astrological investigations, had a laboratory built at his Uraniborg observatory/research institute. Michael Sendivogius (Michał Sędziwój, 1566–1636), a Polish alchemist, philosopher, medical doctor and pioneer of chemistry wrote mystical works but is also credited with distilling oxygen in a lab sometime around 1600. Sendivogious taught his technique to Cornelius Drebbel who, in 1621, applied this in a submarine. Isaac Newton devoted considerably more of his writing to the study of alchemy (see Isaac Newton's


id: alchemy-20260505-8
file: data/en.wikipedia.org/wiki/Alchemy-8.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
=== Women === Several women appear in the earliest history of alchemy. Michael Maier names four women who were able to make the philosophers' stone: Mary the Jewess, Cleopatra the Alchemist, Medera, and Taphnutia. Zosimos's sister Theosebia (later known as Euthica the Arab) and Isis the Prophetess also played roles in early alchemical texts. The first alchemist whose name we know was Mary the Jewess (c. 200 A.D.). Early sources claim that Mary (or Maria) devised a number of improvements to alchemical equipment and tools as well as novel techniques in chemistry. Her best known advances were in heating and distillation processes. The laboratory water-bath, known eponymously (especially in France) as the bain-marie, is said to have been invented or at least improved by her. Essentially a double-boiler, it was (and is) used in chemistry for processes that required gentle heating. The tribikos (a modified distillation apparatus) and the kerotakis (a more intricate apparatus used especially for sublimations) are two other advancements in the process of distillation that are credited to her. Although we have no writing from Mary herself, she is known from the early-fourth-century writings of Zosimos of Panopolis. After the Greco-Roman period, women's names appear less frequently


id: alchemy-20260505-9
file: data/en.wikipedia.org/wiki/Alchemy-9.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
Western alchemical theory corresponds to the worldview of late antiquity in which it was born. Concepts were imported from Neoplatonism and earlier Greek cosmology. As such, the classical elements appear in alchemical writings, as do the seven classical planets and the corresponding seven metals of antiquity. Similarly, the gods of the Roman pantheon who are associated with these luminaries are discussed in alchemical literature. The concepts of prima materia and anima mundi are central to the theory of the philosopher's stone. === Magnum opus === The Great Work of Alchemy is often described as a series of four stages represented by colours. nigredo, a blackening or melanosis albedo, a whitening or leucosis citrinitas, a yellowing or xanthosis rubedo, a reddening, purpling, or iosis == Modernity == Due to the complexity and obscurity of alchemical literature, and the 18th-century diffusion of remaining alchemical practitioners into the area of chemistry, the general understanding of alchemy in the 19th and 20th centuries was influenced by several distinct and radically different interpretations. Those focusing on the exoteric, such as historians of science Lawrence M. Principe and William R. Newman, have interpreted the Decknamen ('code words') of alchemy as physical substances. These scholars have reconstructed


id: alchemy-20260505-10
file: data/en.wikipedia.org/wiki/Alchemy-10.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
Alchemy has had a long-standing relationship with art, evident in both alchemical texts and mainstream entertainment. Literary alchemy appears throughout the history of English literature from William Shakespeare to J. K. Rowling, and also the popular Japanese manga Fullmetal Alchemist. Here, characters or plot structure follow an alchemical magnum opus. In the 14th century, Chaucer began a trend of alchemical satire that can still be seen in recent fantasy works, such as those of the late Sir Terry Pratchett. Another literary work inspired by the alchemical tradition is the 1988 novel The Alchemist by Brazilian writer Paulo Coelho. Visual artists have had a similar relationship with alchemy. While some used it as a source of satire, others worked with the alchemists themselves or integrated alchemical thought or symbols in their work. Music was also present in the works of alchemists and continues to influence popular performers. In the last hundred years, alchemists have been portrayed in a magical and spagyric role in fantasy fiction, film, television, novels, comics, and video games. === Science === One goal of alchemy, the transmutation of base substances into gold, is now known to be impossible by means of traditional chemistry, but possible by other


id: alchemy-20260505-11
file: data/en.wikipedia.org/wiki/Alchemy-11.md
category: reference
title: Alchemy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Alchemy
date_saved: 2026-05-05T09:32:51.562169+00:00
instance: kb-cron
parent: alchemy-20260505-0
summary:
==== Studies ==== Dylan M. Burns, " μίξεώς τινι τέχνῃ κρείττονι : Alchemical Metaphor in the Paraphrase of Shem (NHC VII,1) ", Aries 15 (2015), p. 79–106. Alberto Camplani, " Procedimenti magico-alchemici e discorso filosofico ermetico " in Giuliana Lanata (ed.), Il Tardoantico alle soglie del Duemila, ETS, 2000, p. 73–98. Alberto Camplani and Marco Zambon, " Il sacrificio come problema in alcune correnti filosofice di età imperiale ", Annali di storia dell'esegesi 19 (2002), p. 59–99. Régine Charron and Louis Painchaud, " 'God is a Dyer,' The Background and Significance of a Puzzling Motif in the Coptic Gospel According to Philip (CG II, 3), Le Muséon 114 (2001), p. 41-50. Régine Charron, " The Apocryphon of John (NHC II,1) and the Greco-Egyptian Alchemical Literature ", Vigiliae Christinae 59 (2005), p. 438-456. Philippe Derchain, "L'Atelier des Orfèvres à Dendara et les origines de l'alchimie," Chronique d'Égypte, vol. 65, no 130, 1990, p. 219–242. Korshi Dosoo, " A History of the Theban Magical Library ", Bulletin of the American Society of Papyrologists 53 (2016), p. 251–274. Olivier Dufault, Early Greek Alchemy, Patronage and Innovation in Late Antiquity, California Classical Studies, 2019, Early Greek Alchemy, Patronage and Innovation in Late Antiquity. Sergio


id: annals-of-philosophy-20260505-0
file: data/en.wikipedia.org/wiki/Annals_of_Philosophy-0.md
category: reference
title: Annals of Philosophy
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Annals_of_Philosophy
date_saved: 2026-05-05T09:32:52.713869+00:00
instance: kb-cron
parent: annals-of-philosophy-20260505-0
summary:
Annals of Philosophy; or, Magazine of Chemistry, Mineralology, Mechanics, Natural History, Agriculture and the Arts was a learned journal founded in 1813 by the Scottish chemist Thomas Thomson. It shortly became a leader in its field of commercial scientific periodicals. Contributors included John George Children, Edward Daniel Clarke, Philip Crampton, Alexander Crichton, James Cumming, John Herapath, William George Horner, Thomas Dick Lauder, John Miers, Matthew Paul Moyle, Robert Porrett, James Thomson, and Charles Wheatstone. Thomson edited it until 1821, when he was succeeded in 1821 by Richard Phillips. The journal was bought by Richard Taylor in 1827, and closed down for the benefit of the Philosophical Magazine. The Annals of Philosophy were issued monthly following a standard pattern. Often the first article was a biographical article (10 pages) on a living or recently deceased scientist. This was then followed by a series of extended pieces (5-10 pages) on particular topics, sometimes by eminent authors. Then there were shorter news items and correspondence. Summaries followed: first of the proceedings of learned bodies (Royal Society, Linnean, French Institute -if available: the Napoleonic Wars made communications with the continent difficult at first, etc.), then of patents, and finally of new books. The last


id: biofact-philosophy-20260505-0
file: data/en.wikipedia.org/wiki/Biofact_(philosophy)-0.md
category: reference
title: Biofact (philosophy)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Biofact_(philosophy)
date_saved: 2026-05-05T09:32:54.054666+00:00
instance: kb-cron
parent: biofact-philosophy-20260505-0
summary:
In philosophy and sociology, a biofact is a being that is both an artifact and living being, or both natural and artificial. This being has been created by purposive human action but exists by processes of growth. The word is a neologism coined from the combination of the words bios and artifact. There are sources who cite some creations of genetic engineering as examples of biofacts. == History == Biofact was introduced as early as 2001 by the German philosopher Nicole C. Karafyllis although her book Biofakte published in 2003 is commonly used as reference for the introduction of the term. According to Karafyllis, the word biofact first appeared in a German article (entitled 'Biofakt und Artefakt') in 1943, written by the Austrian protozoologist Bruno M. Klein. Addressing both microscopy and philosophy, Klein named a biofact something that is a visible dead product emerging from a living being while this being is still alive (e.g. a shell). However, Klein's distinction operated with the difference biotic/abiotic and dead/alive, not with nature/technology and growth/man-made. For her part, Karafyllis described biofact as a hermeneutic concept that allows the comparison between nature and technology in the domain of the living. == Philosophy == With


id: cardiocentric-hypothesis-20260505-0
file: data/en.wikipedia.org/wiki/Cardiocentric_hypothesis-0.md
category: reference
title: Cardiocentric hypothesis
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Cardiocentric_hypothesis
date_saved: 2026-05-05T09:32:55.250568+00:00
instance: kb-cron
parent: cardiocentric-hypothesis-20260505-0
summary:
According to the cardiocentric hypothesis, the heart is the primary location of human emotions, cognition, and awareness. This notion may be traced back to ancient civilizations such as Egypt and Greece, where the heart was regarded not only as a physical organ but also as a repository of emotions and wisdom. Aristotle, a well-known Greek philosopher in this field, contributed to the notion by thinking the heart to be the centre of both emotions and intellect. He believed that the heart was the center of the psycho-physiological system and that it was responsible for controlling sensation, thought, and body movement. He also observed that the heart was the origin of the veins in the body and that the existence of pneuma in the heart was to function as a messenger, traveling through blood vessels to produce sensation. This point of view remained throughout history, spanning the Middle Ages and Renaissance, influencing medical and intellectual debate. An opposing theory called "cephalocentrism", which proposed that the brain played the dominant role in controlling the body, was first introduced by Pythagoras in 550 BC, who argued that the soul resides in the brain and is immortal. His statements were supported by Plato, Hippocrates,


id: cardiocentric-hypothesis-20260505-1
file: data/en.wikipedia.org/wiki/Cardiocentric_hypothesis-1.md
category: reference
title: Cardiocentric hypothesis
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Cardiocentric_hypothesis
date_saved: 2026-05-05T09:32:55.250568+00:00
instance: kb-cron
parent: cardiocentric-hypothesis-20260505-0
summary:
=== Europe === In the Middle Ages, the German Catholic friar Albertus Magnus made contributions to physiology and biology. His treatise was based on Galen's cephalocentric theory and was profoundly affected by Avicenna's preeminent Canon, which itself had been influenced by Aristotle. He combined these ideas in a new way which suggested that nerves branched off from the brain but that the origin was the heart. He concluded that philosophically, all matters originated from the heart, and in the corporeal explanation, all nerves started from the brain. William Harvey, an early modern English physiologist, also agreed with Aristotle's cardiocentric view. He was the first to describe the basic operation of the circulatory system, by which blood was pumped by the heart to the rest of the body, in detail. He explained that the heart was the centre of the body and the source of life in his treatise De Motu Cordis et Sanguinis in Animalibus. == Cephalocentric perspective == Hippocrates of Kos was the first to suggest that the brain was the seat of the soul and intelligence. From his treatise De morbo sacro, he pointed out that the brain controls the rest of the body and is responsible for


id: classical-element-20260505-0
file: data/en.wikipedia.org/wiki/Classical_element-0.md
category: reference
title: Classical element
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Classical_element
date_saved: 2026-05-05T09:32:56.401003+00:00
instance: kb-cron
parent: classical-element-20260505-0
summary:
The classical elements typically refer to earth, water, fire, air, and (later) aether which were proposed to explain the nature and complexity of all matter in terms of simpler substances. Ancient cultures in Greece, Angola, Tibet, India, and Mali had similar lists which sometimes referred, in local languages, to "air" as "wind", and to "aether" as "space". These different cultures and even individual philosophers had widely varying explanations concerning their attributes and how they related to observable phenomena as well as cosmology. Sometimes these theories overlapped with mythology and were personified in deities. Some of these interpretations included atomism (the idea of very small, indivisible portions of matter), but other interpretations considered the elements to be divisible into infinitely small pieces without changing their nature. While the classification of the material world among the ancient Indians, Hellenistic Egyptians, and ancient Greeks into air, earth, fire, and water was more philosophical; scientists of the Middle Ages used practical, experimental observation to classify materials. In Europe, the ancient Greek concept, devised by Empedocles, evolved into the systematic classifications of Aristotle and Hippocrates. This evolved slightly into the medieval system, and eventually became the object of experimental verification in the 17th century, at


id: classical-element-20260505-1
file: data/en.wikipedia.org/wiki/Classical_element-1.md
category: reference
title: Classical element
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Classical_element
date_saved: 2026-05-05T09:32:56.401003+00:00
instance: kb-cron
parent: classical-element-20260505-0
summary:
==== Aether ==== Aristotle added a fifth element, aether (αἰθήρ aither), as the quintessence, reasoning that whereas fire, earth, air, and water were earthly and corruptible, since no changes had been perceived in the heavenly regions, the stars cannot be made out of any of the four elements but must be made of a different, unchangeable, heavenly substance. It had previously been believed by pre-Socratics such as Empedocles and Anaxagoras that aether, the name applied to the material of heavenly bodies, was a form of fire. Aristotle himself did not use the term aether for the fifth element, and strongly criticised the pre-Socratics for associating the term with fire. He preferred a number of other terms indicating eternal movement, thus emphasising the evidence for his discovery of a new element. These five elements have been associated since Plato's Timaeus with the five platonic solids. Earth was associated with the cube, air with the octahedron, water with the icosahedron, and fire with the tetrahedron. Of the fifth Platonic solid, the dodecahedron, Plato obscurely remarked, "...the god used [it] for arranging the constellations on the whole heaven". Aristotle added a fifth element, aither (aether in Latin, "ether" in English) and postulated that


id: classical-element-20260505-2
file: data/en.wikipedia.org/wiki/Classical_element-2.md
category: reference
title: Classical element
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Classical_element
date_saved: 2026-05-05T09:32:56.401003+00:00
instance: kb-cron
parent: classical-element-20260505-0
summary:
Just as a skilled butcher or his apprentice, having killed a cow, would sit at a crossroads cutting it up into pieces, the monk contemplates this very body — however it stands, however it is disposed — in terms of properties: 'In this body there is the earth property, the liquid property, the fire property, & the wind property.' Tibetan Buddhist medical literature speaks of the pañca mahābhūta (five elements) or "elemental properties": earth, water, fire, wind, and space. The concept was extensively used in traditional Tibetan medicine. Tibetan Buddhist theology, tantra traditions, and "astrological texts" also spoke of them making up the "environment, [human] bodies," and at the smallest or "subtlest" level of existence, parts of thought and the mind. Also at the subtlest level of existence, the elements exist as "pure natures represented by the five female buddhas", Ākāśadhātviśvarī, Buddhalocanā, Mamakī, Pāṇḍarāvasinī, and Samayatārā, and these pure natures "manifest as the physical properties of earth (solidity), water (fluidity), fire (heat and light), wind (movement and energy), and" the expanse of space. These natures exist as all "qualities" that are in the physical world and take forms in it. == Ancient African philosophy == === Central Africa === In


id: classical-element-20260505-3
file: data/en.wikipedia.org/wiki/Classical_element-3.md
category: reference
title: Classical element
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Classical_element
date_saved: 2026-05-05T09:32:56.401003+00:00
instance: kb-cron
parent: classical-element-20260505-0
summary:
Earth (South) represents the youth cycle, summer, the Indigenous race, and cedar medicine. Fire (East) represents the birth cycle, spring, the Asian race, and tobacco medicine. Wind/Air (North) represents the elder cycle, winter, the European race, and sweetgrass medicine. Water (West) represents the adulthood cycle, autumn, the African race, and sage medicine. == Modern history == === Chemical element === The Aristotelian tradition and medieval alchemy eventually gave rise to modern chemistry, scientific theories and new taxonomies. By the time of Antoine Lavoisier, for example, a list of elements would no longer refer to classical elements. Some modern scientists see a parallel between the classical elements and the four states of matter: solid, liquid, gas and weakly ionized plasma. Modern science recognises classes of elementary particles which have no substructure (or rather, particles that are not made of other particles) and composite particles having substructure (particles made of other particles). === Western astrology === Western astrology uses the four classical elements in connection with astrological charts and horoscopes. The twelve signs of the zodiac are divided into the four elements: Fire signs are Aries, Leo and Sagittarius, Earth signs are Taurus, Virgo and Capricorn, Air signs are Gemini, Libra and


id: corpuscular-theory-of-light-20260505-0
file: data/en.wikipedia.org/wiki/Corpuscular_theory_of_light-0.md
category: reference
title: Corpuscular theory of light
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Corpuscular_theory_of_light
date_saved: 2026-05-05T09:32:57.557855+00:00
instance: kb-cron
parent: corpuscular-theory-of-light-20260505-0
summary:
In optics, the corpuscular theory of light states that light is made up of small discrete particles called "corpuscles" (little particles) which travel in a straight line with a finite velocity and possess impetus. This notion was based on an alternate description of atomism of the time period. Isaac Newton laid the foundations for this theory through his work in optics. This early conception of the particle theory of light was an early forerunner to the modern understanding of the photon. This theory came to dominate the conceptions of light in the eighteenth century, displacing the previously prominent vibration theories, where light was viewed as "pressure" of the medium between the source and the receiver, first championed by René Descartes, and later in a more refined form by Christiaan Huygens. In part correct, being able to successfully explain refraction, reflection, rectilinear propagation and to a lesser extent diffraction, the theory would fall out of favor in the early nineteenth century, as the wave theory of light amassed new experimental evidence. The modern understanding of light is the concept of wave-particle duality. == Corpuscular theory of matter == === Mechanical philosophy === In the early 17th century, natural philosophers began to


id: corpuscular-theory-of-light-20260505-1
file: data/en.wikipedia.org/wiki/Corpuscular_theory_of_light-1.md
category: reference
title: Corpuscular theory of light
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Corpuscular_theory_of_light
date_saved: 2026-05-05T09:32:57.557855+00:00
instance: kb-cron
parent: corpuscular-theory-of-light-20260505-0
summary:
Isaac Newton worked on optics throughout his research career, conducting various experiments and developing hypotheses to explain his results. He dismissed Descartes' theory of light because he rejected Descartes’ understanding of space, which derived from it. With the publication of Opticks in 1704, Newton for the first time took a clear position supporting a corpuscular interpretation, though it would fall on his followers to systemise the theory. In the 1718 edition of Opticks, Newton added several uncertain hypotheses about the nature of light, formulated as queries. In query (Qu.) 16, he wondered whether the way a quavering motion of a finger pressing against the bottom of the eye causes the sensation of circles of colour is similar to how light affects the retina, and whether the independent continuation of the induced sensation for about a second indicates a vibrating nature of the motions in the eye. In Qu. 17, Newton compared the vibrations to the waves propagating in concentric circles after a stone has been thrown in water, and to "the Vibrations or Tremors excited in the Air by percussion". He therefore proposed that light rays would similarly excite waves of vibrations in a reflecting or refracting medium, which in


id: cosmic-pluralism-20260505-0
file: data/en.wikipedia.org/wiki/Cosmic_pluralism-0.md
category: reference
title: Cosmic pluralism
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Cosmic_pluralism
date_saved: 2026-05-05T09:32:58.727360+00:00
instance: kb-cron
parent: cosmic-pluralism-20260505-0
summary:
Cosmic pluralism, the plurality of worlds, or simply pluralism, describes the belief in numerous "worlds" (planets, dwarf planets or natural satellites) in addition to Earth (possibly an infinite number), which may harbour extraterrestrial life. The debate over pluralism began as early as the time of Anaximander (c. 610 – c. 546 BC) as a metaphysical argument, long predating the scientific Copernican conception that the Earth is one of numerous planets. It has continued, in a variety of forms, until the modern era. == Ancient Greek debates == In Greek times, the debate was largely philosophical and did not conform to present notions of cosmology. Cosmic pluralism was a corollary to notions of infinity, and the purported multitude of life-bearing worlds were more akin to parallel universes (either contemporaneously in space or infinitely recurring in time) than to different solar systems. After Anaximander opened the door to an infinite universe, infinite higher dimensions, and an infinite amount of universes and other classes of verses, a strong pluralist stance was adopted by the atomists, notably Leucippus, Democritus, Epicurus—whose Epistle to Herodotus clearly lays out the Doctrine of Innumerable Worlds—and Lucretius who elaborates this Doctrine in his work De rerum natura. Anaxarchus told


id: cosmogony-20260505-0
file: data/en.wikipedia.org/wiki/Cosmogony-0.md
category: reference
title: Cosmogony
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Cosmogony
date_saved: 2026-05-05T09:32:59.903365+00:00
instance: kb-cron
parent: cosmogony-20260505-0
summary:
Cosmogony, also spelled as cosmogeny, or cosmogenesis, is any model concerning the origin of the cosmos or the universe. == Types == While cosmogony generally refers to origin stories, the nature and subject of these stories varies with times and sources. Ancient Greece developed a cosmogony focused on the origin of matter, space, and time with a transition from Chaos to Cosmos. This was a form of "philosophical cosmogony" that is distinct from modern empirical science but which nevertheless dealt with many similar questions. Another type of cosmogony focuses on the formation and evolution of the Solar System. or sometimes the formation of galaxies. The standard cosmological model of the early development of the universe is the Big Bang theory, but it is based on a model known to fail at the very earliest times. Thus modern cosmogony is not generally a consequence of modern cosmology theories. == Scientific cosmogenesis == A Big Bang model for the dynamics of the universe is widely agreed among cosmologists. Like most physical models, Big Bang models describe changes of state. Few physical models are designed to determine initial conditions: initial states are given by experimental measurements or by hypothesis. In cosmology, the initial


id: cosmogony-20260505-1
file: data/en.wikipedia.org/wiki/Cosmogony-1.md
category: reference
title: Cosmogony
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Cosmogony
date_saved: 2026-05-05T09:32:59.903365+00:00
instance: kb-cron
parent: cosmogony-20260505-0
summary:
Creation ex nihilo in which the creation is through the thought, word, dream or bodily secretions of a divine being from initial state of nothing. Earth diver creation in which a diver, usually a bird or amphibian sent by a creator, plunges to the seabed through a primordial ocean to bring up sand or mud which develops into a terrestrial world. Emergence myths in which progenitors pass through a series of worlds and metamorphoses until reaching the present world. Creation by the dismemberment of a primordial being, as in the Ymir motif, otherwise known as the world parent myth. Creation by the splitting or ordering of a primordial unity such as the cracking of a cosmic egg or a bringing order from chaos. == Compared with cosmology == In the humanities, the distinction between cosmogony and cosmology is blurred. For example, in theology, the cosmological argument for the existence of God (pre-cosmic cosmogonic bearer of personhood) is an appeal to ideas concerning the origin of the universe and is thus cosmogonical. Some religious cosmogonies have an impersonal first cause (for example Taoism). However, in astronomy, cosmogony can be distinguished from cosmology, which studies the universe and its existence, but does


id: de-mirabilibus-sacrae-scripturae-20260505-0
file: data/en.wikipedia.org/wiki/De_mirabilibus_sacrae_scripturae-0.md
category: reference
title: De mirabilibus sacrae scripturae
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/De_mirabilibus_sacrae_scripturae
date_saved: 2026-05-05T09:33:01.055248+00:00
instance: kb-cron
parent: de-mirabilibus-sacrae-scripturae-20260505-0
summary:
De mirabilibus sacrae scripturae (English: On the Miraculous Things in Sacred Scripture) is a Latin treatise written around 655 by an anonymous Irish writer and philosopher known as Augustinus Hibernicus or the Irish Augustine. The author's nickname is in reference to the philosopher Augustine of Hippo. This pseudo-Augustine was born in Ireland sometime in the first half of the seventh century and is noted especially for his natural philosophy. Around the year 655 he wrote a treatise called De mirabilibus Sacrae Scripturae. It has long been regarded as an exceptional work, in that it demonstrates a strictly scientific approach in the matter of making direct observations of nature and subjecting them to a strictly logical interpretation. His treatise seeks to explain each miracle in the Scriptures as an extreme case of phenomena, yet still within the laws of nature. Augustine also gives a list of the terrestrial mammals of Ireland, and solves the problem of how they reached Ireland after the flood of Noah by proposing a solution – hundreds of years ahead of its time – that the island had been cut off from continental Europe by marine erosion. == Further reading == Bracken, Damian (1998), "Rationalism and the


id: diatribe-de-progidiosis-crucibus-20260505-0
file: data/en.wikipedia.org/wiki/Diatribe_de_Progidiosis_Crucibus-0.md
category: reference
title: Diatribe de Progidiosis Crucibus
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Diatribe_de_Progidiosis_Crucibus
date_saved: 2026-05-05T09:33:02.221791+00:00
instance: kb-cron
parent: diatribe-de-progidiosis-crucibus-20260505-0
summary:
Diatribe de progidiosis crucibus is a 1661 work by the Jesuit scholar Athanasius Kircher. It was printed in Rome by Blasius Deversin and dedicated to Archduke Leopold Wilhelm of Austria. A second edition of the work was published in Rome in 1666 and a German translation appeared in Gaspar Schott's Joco-seriorum naturae et artis (Würzburg, 1666). Diatribe is Kircher's most succinct and explicit statement in favour of seeking rational causes for phenomena through an understanding of natural laws, derived from observation, rather than seeking miraculous explanations. This continued the theme he had taken up in Scrutinium Physico-Medicum (1658) and pursued in greater detail in Mundus Subterraneus (1665). During an 1660 eruption of Vesuvius, small cross-shaped objects fell from the sky. They were seen as a message from the patron saint Saint Gennaro by the superstitious population of Naples. Kircher visited the volcano to investigate the phenomenon, and concluded that fine ash and moisture had settled on cloth, taking a cruciform shape defined by the weave itself. Kircher noted that the crosses had been seen on linen cloth but not on garments of wool, and that they had appeared only under certain specific conditions of temperature and moisture, causing "guttulae nitrosae"


id: edinburgh-philosophical-journal-20260505-0
file: data/en.wikipedia.org/wiki/Edinburgh_Philosophical_Journal-0.md
category: reference
title: Edinburgh Philosophical Journal
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Edinburgh_Philosophical_Journal
date_saved: 2026-05-05T09:33:03.370986+00:00
instance: kb-cron
parent: edinburgh-philosophical-journal-20260505-0
summary:
The Edinburgh Philosophical Journal was founded by its editors, Robert Jameson and David Brewster in 1819 as a scientific journal to publish articles on the latest science of the day. In 1826 the two editors fell out, and Jameson continued publication as the Edinburgh New Philosophical Journal. Jameson died in 1854, and his place as editor was then taken over by Thomas Anderson, Sir William Jardine, John Hutton Balfour and, for America, Henry Darwin Rogers. In 1864 it was merged into the Quarterly Journal of Science, London. The Edinburgh Philosophical Journal was published by Archibald Constable and Company, then in 1826 publication of the Edinburgh New Philosophical Journal was taken on by Adam Black, later A & C Black of Edinburgh. The journal covered emerging scientific developments in chemistry, optics, electricity, magnetism, and natural history, as well as related topics including practical mechanics, inventions, and scientific instruments. As well as articles by the editors, it published contributions by many of the leading scientists at the time, including Charles Babbage, John Herschel, Robert Stevenson, William Scoresby, Alexander Humboldt and Humphry Davy. It was one of the publishing options for the Royal Society of Edinburgh, and after 1839 it published proceedings of


id: force-20260505-0
file: data/en.wikipedia.org/wiki/Force-0.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
In physics, a force is an action that can cause an object to change its velocity or its shape, or to resist other forces, or to cause changes of pressure in a fluid. In mechanics, force makes ideas like 'pushing' or 'pulling' mathematically precise. Because the magnitude and direction of a force are both important, force is a vector quantity (force vector). The SI unit of force is the newton (N), and force is often represented by the symbol F. Force plays an important role in classical mechanics. The concept of force is central to all three of Newton's laws of motion. Types of forces often encountered in classical mechanics include elastic, frictional, contact or "normal" forces, and gravitational. The rotational version of force is torque, which produces changes in the rotational speed of an object. In an extended body, each part applies forces on the adjacent parts; the distribution of such forces through the body is the internal mechanical stress. In the case of multiple forces, if the net force on an extended body is zero the body is in equilibrium. In modern physics, which includes relativity and quantum mechanics, the laws governing motion are revised to rely on


id: force-20260505-1
file: data/en.wikipedia.org/wiki/Force-1.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
Sir Isaac Newton described the motion of all objects using the concepts of inertia and force. In 1687, Newton published his magnum opus, Philosophiæ Naturalis Principia Mathematica. In this work Newton set out three laws of motion that have dominated the way forces are described in physics to this day. The precise ways in which Newton's laws are expressed have evolved in step with new mathematical approaches. === First law === Newton's first law of motion states that the natural behavior of an object at rest is to continue being at rest, and the natural behavior of an object moving at constant speed in a straight line is to continue moving at that constant speed along that straight line. The latter follows from the former because of the principle that the laws of physics are the same for all inertial observers, i.e., all observers who do not feel themselves to be in motion. An observer moving in tandem with an object will see it as being at rest. So, its natural behavior will be to remain at rest with respect to that observer, which means that an observer who sees it moving at constant speed in a straight line will


id: force-20260505-2
file: data/en.wikipedia.org/wiki/Force-2.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
=== Defining "force" === Some textbooks use Newton's second law as a definition of force. However, for the equation F = m a {\displaystyle \mathbf {F} =m\mathbf {a} } for a constant mass m {\displaystyle m} to then have any predictive content, it must be combined with further information. Moreover, inferring that a force is present because a body is accelerating is only valid in an inertial frame of reference. The question of which aspects of Newton's laws to take as definitions and which to regard as holding physical content has been answered in various ways, which ultimately do not affect how the theory is used in practice. Notable physicists, philosophers and mathematicians who have sought a more explicit definition of the concept of force include Ernst Mach and Walter Noll. == Combining forces == Forces act in a particular direction and have sizes dependent upon how strong the push or pull is. Because of these characteristics, forces are classified as "vector quantities". This means that forces follow a different set of mathematical rules than physical quantities that do not have direction (denoted scalar quantities). For example, when determining what happens when two forces act on the same object, it


id: force-20260505-3
file: data/en.wikipedia.org/wiki/Force-3.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
Static equilibrium was understood well before the invention of classical mechanics. Objects that are not accelerating have zero net force acting on them. The simplest case of static equilibrium occurs when two forces are equal in magnitude but opposite in direction. For example, an object on a level surface is pulled (attracted) downward toward the center of the Earth by the force of gravity. At the same time, a force is applied by the surface that resists the downward force with equal upward force (called a normal force). The situation produces zero net force and hence no acceleration. Pushing against an object that rests on a frictional surface can result in a situation where the object does not move because the applied force is opposed by static friction, generated between the object and the table surface. For a situation with no movement, the static friction force exactly balances the applied force resulting in no acceleration. The static friction increases or decreases in response to the applied force up to an upper limit determined by the characteristics of the contact between the surface and the object. A static equilibrium between two forces is the most usual way of measuring forces, using


id: force-20260505-4
file: data/en.wikipedia.org/wiki/Force-4.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
For an object in free-fall, this force is unopposed and the net force on the object is its weight. For objects not in free-fall, the force of gravity is opposed by the reaction forces applied by their supports. For example, a person standing on the ground experiences zero net force, since a normal force (a reaction force) is exerted by the ground upward on the person that counterbalances his weight that is directed downward. Newton's contribution to gravitational theory was to unify the motions of heavenly bodies, which Aristotle had assumed were in a natural state of constant motion, with falling motion observed on the Earth. He proposed a law of gravity that could account for the celestial motions that had been described earlier using Kepler's laws of planetary motion. Newton came to realize that the effects of gravity might be observed in different ways at larger distances. In particular, Newton determined that the acceleration of the Moon around the Earth could be ascribed to the same force of gravity if the acceleration due to gravity decreased as an inverse square law. Further, Newton realized that the acceleration of a body due to gravity is proportional to the mass of


id: force-20260505-5
file: data/en.wikipedia.org/wiki/Force-5.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
When objects are in contact, the force directly between them is called the normal force, the component of the total force in the system exerted normal to the interface between the objects. The normal force is closely related to Newton's third law. The normal force, for example, is responsible for the structural integrity of tables and floors as well as being the force that responds whenever an external force pushes on a solid object. An example of the normal force in action is the impact force on an object crashing into an immobile surface. === Friction === Friction is a force that opposes relative motion of two bodies. At the macroscopic scale, the frictional force is directly related to the normal force at the point of contact. There are two broad classifications of frictional forces: static friction and kinetic friction. The static friction force ( F s f {\displaystyle \mathbf {F} _{\mathrm {sf} }} ) will exactly oppose forces applied to an object parallel to a surface up to the limit specified by the coefficient of static friction ( μ s f {\displaystyle \mu _{\mathrm {sf} }} ) multiplied by the normal force ( F N {\displaystyle \mathbf {F} _{\text{N}}}


id: force-20260505-6
file: data/en.wikipedia.org/wiki/Force-6.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
where V {\displaystyle V} is the volume of the object in the fluid and P {\displaystyle P} is the scalar function that describes the pressure at all locations in space. Pressure gradients and differentials result in the buoyant force for fluids suspended in gravitational fields, winds in atmospheric science, and the lift associated with aerodynamics and flight. A specific instance of such a force that is associated with dynamic pressure is fluid resistance: a body force that resists the motion of an object through a fluid due to viscosity. For so-called "Stokes' drag" the force is approximately proportional to the velocity, but opposite in direction: F d = − b v , {\displaystyle \mathbf {F} _{\mathrm {d} }=-b\mathbf {v} ,} where: b {\displaystyle b} is a constant that depends on the properties of the fluid and the dimensions of the object (usually the cross-sectional area), and v {\displaystyle \mathbf {v} } is the velocity of the object. More formally, forces in continuum mechanics are fully described by a stress tensor with terms that are roughly defined as σ = F A , {\displaystyle \sigma ={\frac {F}{A}},} where A {\displaystyle A} is the relevant cross-sectional area for the volume for which


id: force-20260505-7
file: data/en.wikipedia.org/wiki/Force-7.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
with v = d x / d t {\displaystyle \mathbf {v} =\mathrm {d} \mathbf {x} /\mathrm {d} t} the velocity. === Potential energy === Instead of a force, often the mathematically related concept of a potential energy field is used. For instance, the gravitational force acting upon an object can be seen as the action of the gravitational field that is present at the object's location. Restating mathematically the definition of energy (via the definition of work), a potential scalar field U ( r ) {\displaystyle U(\mathbf {r} )} is defined as that field whose gradient is equal and opposite to the force produced at every point: F = − ∇ U . {\displaystyle \mathbf {F} =-\mathbf {\nabla } U.} Forces can be classified as conservative or nonconservative. Conservative forces are equivalent to the gradient of a potential while nonconservative forces are not. === Conservation === A conservative force that acts on a closed system has an associated mechanical work that allows energy to convert only between kinetic or potential forms. This means that for a closed system, the net mechanical energy is conserved whenever a conservative force acts on the system. The force, therefore, is related directly to the


id: force-20260505-8
file: data/en.wikipedia.org/wiki/Force-8.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
remains valid because it is a mathematical definition. But for momentum to be conserved at relativistic relative velocity, v {\displaystyle v} , momentum must be redefined as: p = m 0 v 1 − v 2 / c 2 , {\displaystyle \mathbf {p} ={\frac {m_{0}\mathbf {v} }{\sqrt {1-v^{2}/c^{2}}}},} where m 0 {\displaystyle m_{0}} is the rest mass and c {\displaystyle c} the speed of light. The expression relating force and acceleration for a particle with constant non-zero rest mass m {\displaystyle m} moving in the x {\displaystyle x} direction at velocity v {\displaystyle v} is: F = ( γ 3 m a x , γ m a y , γ m a z ) , {\displaystyle \mathbf {F} =\left(\gamma ^{3}ma_{x},\gamma ma_{y},\gamma ma_{z}\right),} where γ = 1 1 − v 2 / c 2 . {\displaystyle \gamma ={\frac {1}{\sqrt {1-v^{2}/c^{2}}}}.} is called the Lorentz factor. The Lorentz factor increases steeply as the relative velocity approaches the speed of light. Consequently, the greater and greater force must be applied to produce the same acceleration at extreme velocity. The relative velocity cannot reach c {\displaystyle c} . If v {\displaystyle v} is very small compared to c {\displaystyle c} , then γ {\displaystyle


id: force-20260505-9
file: data/en.wikipedia.org/wiki/Force-9.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
In modern particle physics, forces and the acceleration of particles are explained as a mathematical by-product of exchange of momentum-carrying gauge bosons. With the development of quantum field theory and general relativity, it was realized that force is a redundant concept arising from conservation of momentum (4-momentum in relativity and momentum of virtual particles in quantum electrodynamics). The conservation of momentum can be directly derived from the homogeneity or symmetry of space and so is usually considered more fundamental than the concept of a force. Thus the currently known fundamental forces are considered more accurately to be "fundamental interactions". While sophisticated mathematical descriptions are needed to predict, in full detail, the result of such interactions, there is a conceptually simple way to describe them through the use of Feynman diagrams. In a Feynman diagram, each matter particle is represented as a straight line (see world line) traveling through time, which normally increases up or to the right in the diagram. Matter and anti-matter particles are identical except for their direction of propagation through the Feynman diagram. World lines of particles intersect at interaction vertices, and the Feynman diagram represents any force arising from an interaction as occurring at the vertex


id: force-20260505-10
file: data/en.wikipedia.org/wiki/Force-10.md
category: reference
title: Force
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Force
date_saved: 2026-05-05T09:33:04.607426+00:00
instance: kb-cron
parent: force-20260505-0
summary:
=== Electromagnetic === Maxwell's equations and the set of techniques built around them adequately describe a wide range of physics involving force in electricity and magnetism. This classical theory already includes relativity effects. Understanding quantized electromagnetic interactions between elementary particles requires quantum electrodynamics (QED). In QED, photons are fundamental exchange particles, describing all interactions relating to electromagnetism including the electromagnetic force. === Strong nuclear === There are two "nuclear forces", which today are usually described as interactions that take place in quantum theories of particle physics. The strong nuclear force is the force responsible for the structural integrity of atomic nuclei, and gains its name from its ability to overpower the electromagnetic repulsion between protons. The strong force is today understood to represent the interactions between quarks and gluons as detailed by the theory of quantum chromodynamics (QCD). The strong force is the fundamental force mediated by gluons, acting upon quarks, antiquarks, and the gluons themselves. The strong force only acts directly upon elementary particles. A residual is observed between hadrons (notably, the nucleons in atomic nuclei), known as the nuclear force. Here the strong force acts indirectly, transmitted as gluons that form part of the virtual pi and rho


id: great-chain-of-being-20260505-0
file: data/en.wikipedia.org/wiki/Great_chain_of_being-0.md
category: reference
title: Great chain of being
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Great_chain_of_being
date_saved: 2026-05-05T09:33:05.837285+00:00
instance: kb-cron
parent: great-chain-of-being-20260505-0
summary:
The great chain of being (from Latin scala naturae 'ladder of being') is a hierarchical structure of all matter and life, thought by the medieval Islamic world and medieval Christianity to have been decreed by God. The chain begins with God and descends through angels, humans, animals and plants to minerals. The great chain of being is a concept derived from Plato, Aristotle (in his Historia Animalium), Plotinus and Proclus. Further developed during the Middle Ages, it reached full expression in early modern Neoplatonism. == Divisions == The chain of being hierarchy consists of God at the top, above angels, which like him are entirely spirit, without material bodies, and hence unchangeable. Beneath them are humans, consisting both of spirit and matter; they change and die, and are thus essentially impermanent. Lower are animals and plants. At the bottom are the mineral materials of the earth itself; they consist only of matter. Thus, the higher the being is in the chain, the more attributes it has, including all the attributes of the beings below it. The minerals are, in the medieval mind, a possible exception to the immutability of the material beings in the chain, as alchemy promised to turn


id: great-chain-of-being-20260505-1
file: data/en.wikipedia.org/wiki/Great_chain_of_being-1.md
category: reference
title: Great chain of being
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Great_chain_of_being
date_saved: 2026-05-05T09:33:05.837285+00:00
instance: kb-cron
parent: great-chain-of-being-20260505-0
summary:
The set nature of species, and thus the absoluteness of creatures' places in the great chain, came into question during the 18th century. The dual nature of the chain, divided yet united, had always allowed for seeing creation as essentially one continuous whole, with the potential for overlap between the links. Radical thinkers like Jean-Baptiste Lamarck saw a progression of life forms from the simplest creatures striving towards complexity and perfection, a schema accepted by zoologists like Henri de Blainville. The very idea of an ordering of organisms, even if supposedly fixed, laid the basis for the idea of transmutation of species, whether progressive goal-directed orthogenesis or Charles Darwin's undirected theory of evolution. The chain of being continued to be part of metaphysics in 19th-century education, and the concept was well known. The geologist Charles Lyell used it as a metaphor in his 1851 Elements of Geology description of the geological column, where he used the term "missing links" about missing parts of the continuum. The term "missing link" later came to signify transitional fossils, particularly those bridging the gulf between man and beasts. The idea of the great chain, as well as the derived "missing link", was abandoned in


id: holism-and-evolution-20260505-0
file: data/en.wikipedia.org/wiki/Holism_and_Evolution-0.md
category: reference
title: Holism and Evolution
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Holism_and_Evolution
date_saved: 2026-05-05T09:33:07.027969+00:00
instance: kb-cron
parent: holism-and-evolution-20260505-0
summary:
Holism and Evolution is a 1926 book by South African statesman Jan Smuts, in which he coined the word "holism", although Smuts' meaning differs from the modern concept of holism. Smuts defined holism as the "fundamental factor operative towards the creation of wholes in the universe." The book was part of a broader trend of interest in holism in European and colonial academia during the early twentieth century. Smuts based his philosophy of holism on the thoughts behind his earlier book, Walt Whitman: A Study in the Evolution of Personality, written during his time at Cambridge in the early 1890s. The book describes a "process-orientated, hierarchical view of nature" and has been influential among criticisms of reductionism. Smuts' formulation of holism has also been linked with his political-military activity, especially his aspiration to create a league of nations: "the unification of the four provinces in the Union of South Africa, the idea of the British Commonwealth of Nations, and, finally, the great whole resulting from the combination of the peoples of the earth were just a logical progression consistent with his philosophical tenets." Smuts saw the League of Nations as a project that would unify white internationalists and pacify a


id: hylozoism-20260505-0
file: data/en.wikipedia.org/wiki/Hylozoism-0.md
category: reference
title: Hylozoism
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Hylozoism
date_saved: 2026-05-05T09:33:08.199147+00:00
instance: kb-cron
parent: hylozoism-20260505-0
summary:
Hylozoism is the philosophical doctrine according to which all matter is alive or animated, either in itself or as participating in the action of a superior principle, usually the world-soul (anima mundi). The theory holds that matter is unified with life or spiritual activity. The word is a 17th-century term formed from the Greek words ὕλη (hyle: "wood, matter") and ζωή (zoē: "life"), which was coined by the English Platonist philosopher Ralph Cudworth in 1678. == Hylozoism in Ancient Greek Philosophy == Hylozoism in Western philosophy can be traced back to ancient Greece. The Milesian philosophers Thales, Anaximander, and Anaximenes, can be described as hylozoists. Philosopher David Skrbina states that hylozoism was implicit in early Greek philosophy, and was not a doctrine that was typically challenged. "For the Milesians, matter (hyle) possessed life (zoe) as an essential quality. Something like hylozoism was simply accepted as a brute condition of reality." Though hylozoism was implicit in early Greek thought, the philosopher Heraclitus specifically used the term zoe, making him explicitly hylozoist. The hylozoism of the pre-Socratic philosophers such as Thales and Heraclitus influenced later Greek philosophers such as Plato, Aristotle, and the Stoics. Though hylozoism was common in ancient Greek thought,


id: hylozoism-20260505-1
file: data/en.wikipedia.org/wiki/Hylozoism-1.md
category: reference
title: Hylozoism
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Hylozoism
date_saved: 2026-05-05T09:33:08.199147+00:00
instance: kb-cron
parent: hylozoism-20260505-0
summary:
== Contemporary hylozoism == Immanuel Kant presented arguments against hylozoism in the third chapter of his 1786 book Metaphysische Anfangsgründe der Naturwissenschaften ("First Metaphysical Principles of Natural Science") and also in his 1781 book Kritik der reinen Vernunft ("Critique of Pure Reason"). Yet, in our times, scientific hylozoism – whether modified, or keeping the trend to make all beings conform to some uniform pattern, to which the concept was adhered in modernity by Herbert Spencer, Hermann Lotze, and Ernst Haeckel – was often called upon as a protest against a mechanistic worldview. In the 19th century, Haeckel developed a materialist form of hylozoism, specially against Rudolf Virchow's and Hermann von Helmholtz's mechanical views of humans and nature. In his Die Welträtsel of 1899 (The Riddle of the Universe 1901), Haeckel upheld a unity of organic and inorganic nature and derived all actions of both types of matter from natural causes and laws. Thus, his form of hylozoism reverses the usual course by maintaining that living and nonliving things are essentially the same, and by erasing the distinction between the two and stipulating that they behave by a single set of laws. In contrast, the Argentine-German neurobiological tradition terms hylozoic hiatus


id: journal-of-natural-philosophy-chemistry-and-the-arts-20260505-0
file: data/en.wikipedia.org/wiki/Journal_of_Natural_Philosophy,_Chemistry,_and_the_Arts-0.md
category: reference
title: Journal of Natural Philosophy, Chemistry, and the Arts
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Journal_of_Natural_Philosophy,_Chemistry,_and_the_Arts
date_saved: 2026-05-05T09:33:09.347080+00:00
instance: kb-cron
parent: journal-of-natural-philosophy-chemistry-and-the-arts-20260505-0
summary:
A Journal of Natural Philosophy, Chemistry, and the Arts, generally known as Nicholson's Journal, was the first monthly scientific journal in Great Britain. William Nicholson began it in 1797 and was the editor until it merged with another journal in January 1814. Nicholson's journal would accept short papers, written by new or anonymous authors, and decide whether to publish them relatively quickly. These attributes distinguished the new journal from the established scientific journal The Philosophical Transactions of the Royal Society. By one account this less-formal model was so appealing that the next year (1798) a similar startup launched, Alexander Tilloch's Philosophical Magazine, and in January 1813, a further rival, Thomas Thomson's Annals of Philosophy. == Significant articles == Nicholson and Anthony Carlisle split water into hydrogen and oxygen for the first time in 1800 and immediately published their results in the journal. They used Volta's pile (an electric battery) as soon as they learned of it to achieve this electrolysis. Discovery of the element palladium was announced in 1803. The author chose Nicholson's journal in order to remain anonymous at first, and later revealed himself to be William Hyde Wollaston. The journal published the first known aerodynamic analysis of gliders


id: liber-de-orbe-20260505-0
file: data/en.wikipedia.org/wiki/Liber_de_orbe-0.md
category: reference
title: Liber de orbe
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Liber_de_orbe
date_saved: 2026-05-05T09:33:10.505322+00:00
instance: kb-cron
parent: liber-de-orbe-20260505-0
summary:
Liber de orbe was a Latin translation made in 1130s CE of an Arabic work attributed to the 8th century astrologer Mashallah ibn Athari. The work's main topic is cosmology and is considered one of the earliest works on Aristotelian physics available in Latin. == See also == Astrology in medieval Islam == References ==


id: mean-speed-theorem-20260505-0
file: data/en.wikipedia.org/wiki/Mean_speed_theorem-0.md
category: reference
title: Mean speed theorem
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Mean_speed_theorem
date_saved: 2026-05-05T09:33:11.679450+00:00
instance: kb-cron
parent: mean-speed-theorem-20260505-0
summary:
The mean speed theorem, also known as the Merton rule of uniform acceleration, was discovered in the 14th century by the Oxford Calculators of Merton College, and was proved by Nicole Oresme. It states that a uniformly accelerated body (starting from rest, i.e. zero initial velocity) travels the same distance as a body with uniform speed whose speed is half the final velocity of the accelerated body. == Details == Oresme provided a geometrical verification for the generalized Merton rule, which we would express today as s = 1 2 ( v 0 + v f ) t {\displaystyle s={\frac {1}{2}}(v_{0}+v_{\rm {f}})t} (i.e., distance traveled is equal to one half of the sum of the initial v 0 {\displaystyle v_{0}} and final v f {\displaystyle v_{\rm {f}}} velocities, multiplied by the elapsed time t {\displaystyle t} ), by finding the area of a trapezoid. Clay tablets used in Babylonian astronomy (350–50 BC) present trapezoid procedures for computing Jupiter's position and motion. The medieval scientists demonstrated this theorem—the foundation of "the law of falling bodies"—long before Galileo, who is generally credited with it. Oresme's proof is also the first known example of the modelization of a physical problem as a mathematical


id: mechanism-philosophy-20260505-0
file: data/en.wikipedia.org/wiki/Mechanism_(philosophy)-0.md
category: reference
title: Mechanism (philosophy)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Mechanism_(philosophy)
date_saved: 2026-05-05T09:33:14.051618+00:00
instance: kb-cron
parent: mechanism-philosophy-20260505-0
summary:
Mechanism is the belief that natural wholes (principally living things) are similar to complicated machines or artifacts, composed of parts lacking any intrinsic relationship to each other. The doctrine of mechanism in philosophy comes in two different varieties. They are both doctrines of metaphysics, but they are different in scope and ambitions: the first is a global doctrine about nature; the second is a local doctrine about humans and their minds, which is hotly contested. For clarity, we might distinguish these two doctrines as universal mechanism and anthropic mechanism. == Mechanical philosophy == Mechanical philosophy is a form of natural philosophy which compares the universe to a large-scale mechanism (i.e. a machine). Mechanical philosophy is associated with the Scientific Revolution of early modern Europe. One of the first expositions of universal mechanism is found in the opening passages of Leviathan by Thomas Hobbes, published in 1651. Some intellectual historians and critical theorists argue that early mechanical philosophy was tied to disenchantment and the rejection of the idea of nature as living or animated by spirits or angels. Other scholars, however, have noted that early mechanical philosophers nevertheless believed in magic, Christianity and spiritualism. === Mechanism and determinism === Some ancient


id: mechanism-philosophy-20260505-1
file: data/en.wikipedia.org/wiki/Mechanism_(philosophy)-1.md
category: reference
title: Mechanism (philosophy)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Mechanism_(philosophy)
date_saved: 2026-05-05T09:33:14.051618+00:00
instance: kb-cron
parent: mechanism-philosophy-20260505-0
summary:
We may regard the present state of the universe as the effect of the past and the cause of the future. An intellect which at any given moment knew all of the forces that animate nature and the mutual positions of the beings that compose it, if this intellect were vast enough to submit the data to analysis, could condense into a single formula the movement of the greatest bodies of the universe and that of the lightest atom; for such an intellect nothing could be uncertain and the future just like the past would be present before its eyes. === Criticism === Critics argue that although mechanical philosophy includes a wide range of useful observational and principled data, it has not adequately explained the world and its components, and there are weaknesses in its definitions. Among the criticisms made of this philosophy are: Experts in religious studies have criticized the philosophy that God's intervention in the management of the world seems unnecessary. Newton's mechanical philosophy, with all its positive effects on human life, ultimately leads to Deism. It is a stagnant worldview that cannot explain God's constant presence and favor in the world. At the height of this philosophy,


id: mechanism-philosophy-20260505-2
file: data/en.wikipedia.org/wiki/Mechanism_(philosophy)-2.md
category: reference
title: Mechanism (philosophy)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Mechanism_(philosophy)
date_saved: 2026-05-05T09:33:14.051618+00:00
instance: kb-cron
parent: mechanism-philosophy-20260505-0
summary:
=== Criticism === In modern times, philosophers have raised several concerns regarding the manner in which both Descartes and Newton utilized the "scientific methodology" in their formulations of a universal mechanistic metaphysics. Noteworthy is Colin Murray Turbayne, who argued that both Descartes and Newton fell victim to at least three procedural errors while developing a doctrine of universal mechanism. Their first error emerged with the claim that the certainty which characterizes the use of deductive reasoning in the development of the relationship between theorems and principles is present within the natural world in the form of active principles which serve as catalysts for a causal chain of events. In the process, however, both philosophers exported a characteristic of the process of explaining natural events into the natural world itself and suddenly, "nature... obeys the logic of the deductive method. In addition, Descartes and Newton artificially bifurcated the natural world into "causes" (such as "gravity", "resistance" or "attraction") and "effects" (such as "bodies at rest" and "bodies in motion") while asserting that any deductive explanation of the natural world must be founded upon causal relationships. By claiming, however, that causal "laws" or "forces" are inherent within the natural world, both Descartes


id: mechanism-philosophy-20260505-3
file: data/en.wikipedia.org/wiki/Mechanism_(philosophy)-3.md
category: reference
title: Mechanism (philosophy)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Mechanism_(philosophy)
date_saved: 2026-05-05T09:33:14.051618+00:00
instance: kb-cron
parent: mechanism-philosophy-20260505-0
summary:
==== History ==== One of the earliest attempts to use incompleteness to reason about human intelligence was by Gödel himself in his 1951 Gibbs Lecture entitled "Some basic theorems on the foundations of mathematics and their philosophical implications". In this lecture, Gödel uses the incompleteness theorem to arrive at the following disjunction: (a) the human mind is not a consistent finite machine, or (b) there exist Diophantine equations for which it cannot decide whether solutions exist. Gödel finds (b) implausible, and thus seems to have believed the human mind was not equivalent to a finite machine, i.e., its power exceeded that of any finite machine. He recognized that this was only a conjecture, since one could never disprove (b). Yet he considered the disjunctive conclusion to be a "certain fact". In subsequent years, more direct anti-mechanist lines of reasoning were apparently floating around the intellectual atmosphere. In 1960, Hilary Putnam published a paper entitled "Minds and Machines," in which he points out the flaws of a typical anti-mechanist argument. Informally, this is the argument that the (alleged) difference between "what can be mechanically proven" and "what can be seen to be true by humans" shows that human intelligence is not


id: mechanism-philosophy-20260505-4
file: data/en.wikipedia.org/wiki/Mechanism_(philosophy)-4.md
category: reference
title: Mechanism (philosophy)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Mechanism_(philosophy)
date_saved: 2026-05-05T09:33:14.051618+00:00
instance: kb-cron
parent: mechanism-philosophy-20260505-0
summary:
Looked at this way, Gödel's proof suggests – though by no means does it prove! – that there could be some high-level way of viewing the mind/brain, involving concepts which do not appear on lower levels, and that this level might have explanatory power that does not exist – not even in principle – on lower levels. It would mean that some facts could be explained on the high level quite easily, but not on lower levels at all. No matter how long and cumbersome a low-level statement were made, it would not explain the phenomena in question. It is analogous to the fact that, if you make derivation after derivation in Peano arithmetic, no matter how long and cumbersome you make them, you will never come up with one for G – despite the fact that on a higher level, you can see that the Gödel sentence is true. What might such high-level concepts be? It has been proposed for eons, by various holistically or "soulistically" inclined scientists and humanists that consciousness is a phenomenon that escapes explanation in terms of brain components; so here is a candidate at least. There is also the ever-puzzling notion of free will.


id: natura-non-facit-saltus-20260505-0
file: data/en.wikipedia.org/wiki/Natura_non_facit_saltus-0.md
category: reference
title: Natura non facit saltus
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Natura_non_facit_saltus
date_saved: 2026-05-05T09:33:15.178924+00:00
instance: kb-cron
parent: natura-non-facit-saltus-20260505-0
summary:
Natura non facit saltus (Latin for "nature does not make jumps") has been an important principle of natural philosophy. It appears as an axiom in the works of Gottfried Leibniz (New Essays, IV, 16: "la nature ne fait jamais des sauts", "nature never makes jumps"), one of the inventors of the infinitesimal calculus (see Law of Continuity). It is also an essential element of Charles Darwin's treatment of natural selection in his Origin of Species. The Latin translation comes from Linnaeus' Philosophia Botanica. == Overview == The principle expresses the idea that natural things and properties change gradually, rather than suddenly. In a mathematical context, this allows one to assume that the solutions of the governing equations are continuous, and also does not preclude their being differentiable (differentiability implies continuity). Modern day quantum mechanics is sometimes seen as violating the principle, with its idea of discrete transitions between energy states. Erwin Schrödinger in his objections to quantum jumps supported the principle, and initially developed his wave mechanics in order to remove these jumps. In the biological context, the principle was used by Charles Darwin and others to defend the evolutionary postulate that all species develop from earlier species through gradual


id: naturphilosophie-20260505-0
file: data/en.wikipedia.org/wiki/Naturphilosophie-0.md
category: reference
title: Naturphilosophie
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Naturphilosophie
date_saved: 2026-05-05T09:33:16.335531+00:00
instance: kb-cron
parent: naturphilosophie-20260505-0
summary:
"Naturphilosophie" (German for "nature-philosophy") is a term used in English-language philosophy to identify a current in the philosophical tradition of German idealism, as applied to the study of nature in the earlier 19th century. German speakers use the clearer term "Romantische Naturphilosophie", the philosophy of nature developed at the time of the founding of German Romanticism. It is particularly associated with the philosophical work of Friedrich Wilhelm Joseph Schelling and Georg Wilhelm Friedrich Hegel—though it has some clear precursors also. More particularly it is identified with some of the initial works of Schelling during the period 1797–9, in reaction to the views of Johann Gottlieb Fichte, and subsequent developments from Schelling's position. Always controversial, some of Schelling's ideas in this direction are still considered of philosophical interest, even if the subsequent development of experimental natural science had a destructive impact on the credibility of the theories of his followers in Naturphilosophie. Naturphilosophie attempted to comprehend nature in its totality and to outline its general theoretical structure, thus attempting to lay the foundations for the natural sciences. In developing their theories, the German Naturphilosophen found their inspiration in the natural philosophy of the Ancient Greek Ionian philosophers. As an approach to


id: naturphilosophie-20260505-1
file: data/en.wikipedia.org/wiki/Naturphilosophie-1.md
category: reference
title: Naturphilosophie
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Naturphilosophie
date_saved: 2026-05-05T09:33:16.335531+00:00
instance: kb-cron
parent: naturphilosophie-20260505-0
summary:
Schelling's postkantian confrontation with nature itself begins with the overthrow of the Copernican revolution [...] Schelling held that the divisions imposed on nature, by our ordinary perception and thought, do not have absolute validity. They should be interpreted as the outcome of the single formative energy which is the soul or inner aspect of nature. In other words he was a proponent of a variety of organicism. The dynamic series of stages in nature, the forms in which the ideal structure of nature is realized, are matter, as the equilibrium of the fundamental expansive and contractive forces; light, with its subordinate processes (magnetism, electricity, and chemical action); organism, with its component phases of reproduction, irritability and sensibility. The continual change presented to us by experience, taken together with the thought of unity in productive force of nature, leads to the conception of the duality through which nature expresses itself in its varied products. In the introduction to the Ideen he argues against dogmatism, in the terms that a dogmatist cannot explain the organic; and that recourse to the idea of a cosmic creator is a feature of dogmatic systems imposed by the need to explain nature as purposive and unified.


id: optics-20260505-0
file: data/en.wikipedia.org/wiki/Optics-0.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
Optics is the branch of physics that studies the behaviour, manipulation, and detection of electromagnetic radiation, including its interactions with matter and instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light. The study of optics extends to other forms of electromagnetic radiation, including radio waves, microwaves, and X-rays. The term optics is also applied to technology for manipulating beams of elementary charged particles. Most optical phenomena can be accounted for by using the classical electromagnetic description of light, however, complete electromagnetic descriptions of light are often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Historically, the ray-based model of light was developed first, followed by the wave model of light. Progress in electromagnetic theory in the 19th century led to the discovery that light waves were in fact electromagnetic radiation. Some phenomena


id: optics-20260505-1
file: data/en.wikipedia.org/wiki/Optics-1.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
During the Middle Ages, Greek ideas about optics were resurrected and extended by writers in the Muslim world. One of the earliest of these was Al-Kindi (c. 801–873) who wrote on the merits of Aristotelian and Euclidean ideas of optics, favouring the emission theory since it could better quantify optical phenomena. In 984, the Persian mathematician Ibn Sahl wrote the treatise "On burning mirrors and lenses", correctly describing a law of refraction equivalent to Snell's law. He used this law to compute optimum shapes for lenses and curved mirrors. In the early 11th century, Alhazen (Ibn al-Haytham) wrote the Book of Optics (Kitab al-manazir) in which he explored reflection and refraction and proposed a new system for explaining vision and light based on observation and experiment. He rejected the "emission theory" of Ptolemaic optics with its rays being emitted by the eye, and instead put forward the idea that light reflected in all directions in straight lines from all points of the objects being viewed and then entered the eye, although he was unable to correctly explain how the eye captured the rays. Alhazen's work was largely ignored in the Arabic world but it was anonymously translated into Latin around


id: optics-20260505-2
file: data/en.wikipedia.org/wiki/Optics-2.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
In the early 17th century, Johannes Kepler expanded on geometric optics in his writings, covering lenses, reflection by flat and curved mirrors, the principles of pinhole cameras, inverse-square law governing the intensity of light, and the optical explanations of astronomical phenomena such as lunar and solar eclipses and astronomical parallax. He was also able to correctly deduce the role of the retina as the actual organ that recorded images, finally being able to scientifically quantify the effects of different types of lenses that spectacle makers had been observing over the previous 300 years. After the invention of the telescope, Kepler set out the theoretical basis on how they worked and described an improved version, known as the Keplerian telescope, using two convex lenses to produce higher magnification. Optical theory progressed in the mid-17th century with treatises written by philosopher René Descartes, which explained a variety of optical phenomena including reflection and refraction by assuming that light was emitted by objects which produced it. This differed substantively from the ancient Greek emission theory. In the late 1660s and early 1670s, Isaac Newton expanded Descartes's ideas into a corpuscle theory of light, famously determining that white light was a mix of colours


id: optics-20260505-3
file: data/en.wikipedia.org/wiki/Optics-3.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
Reflections can be divided into two types: specular reflection and diffuse reflection. Specular reflection describes the gloss of surfaces such as mirrors, which reflect light in a simple, predictable way. This allows for the production of reflected images that can be associated with an actual (real) or extrapolated (virtual) location in space. Diffuse reflection describes non-glossy materials, such as paper or rock. The reflections from these surfaces can only be described statistically, with the exact distribution of the reflected light depending on the microscopic structure of the material. Many diffuse reflectors are described or can be approximated by Lambert's cosine law, which describes surfaces that have equal luminance when viewed from any angle. Glossy surfaces can give both specular and diffuse reflection. In specular reflection, the direction of the reflected ray is determined by the angle the incident ray makes with the surface normal, a line perpendicular to the surface at the point where the ray hits. The incident and reflected rays and the normal lie in a single plane, and the angle between the reflected ray and the surface normal is the same as that between the incident ray and the normal. This is known as the Law of


id: optics-20260505-4
file: data/en.wikipedia.org/wiki/Optics-4.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
where S1 is the distance from the object to the lens, S2 is the distance from the lens to the image, and f is the focal length of the lens. In the sign convention used here, the object and image distances are positive if the object and image are on opposite sides of the lens. Incoming parallel rays are focused by a converging lens onto a spot one focal length from the lens, on the far side of the lens. This is called the rear focal point of the lens. Rays from an object at a finite distance are focused further from the lens than the focal distance; the closer the object is to the lens, the further the image is from the lens. With diverging lenses, incoming parallel rays diverge after going through the lens, in such a way that they seem to have originated at a spot one focal length in front of the lens. This is the lens's front focal point. Rays from an object at a finite distance are associated with a virtual image that is closer to the lens than the focal point, and on the same side of the lens as the object. The


id: optics-20260505-5
file: data/en.wikipedia.org/wiki/Optics-5.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
Since the Huygens–Fresnel principle states that every point of a wavefront is associated with the production of a new disturbance, it is possible for a wavefront to interfere with itself constructively or destructively at different locations producing bright and dark fringes in regular and predictable patterns. Interferometry is the science of measuring these patterns, usually as a means of making precise determinations of distances or angular resolutions. The Michelson interferometer was a famous instrument which used interference effects to accurately measure the speed of light. The appearance of thin films and coatings is directly affected by interference effects. Antireflective coatings use destructive interference to reduce the reflectivity of the surfaces they coat, and can be used to minimise glare and unwanted reflections. The simplest case is a single layer with a thickness of one-fourth the wavelength of incident light. The reflected wave from the top of the film and the reflected wave from the film/material interface are then exactly 180° out of phase, causing destructive interference. The waves are only exactly out of phase for one wavelength, which would typically be chosen to be near the centre of the visible spectrum, around 550 nm. More complex designs using multiple layers


id: optics-20260505-6
file: data/en.wikipedia.org/wiki/Optics-6.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
Refractive processes take place in the physical optics limit, where the wavelength of light is similar to other distances, as a kind of scattering. The simplest type of scattering is Thomson scattering which occurs when electromagnetic waves are deflected by single particles. In the limit of Thomson scattering, in which the wavelike nature of light is evident, light is dispersed independent of the frequency, in contrast to Compton scattering which is frequency-dependent and strictly a quantum mechanical process, involving the nature of light as particles. In a statistical sense, elastic scattering of light by numerous particles much smaller than the wavelength of the light is a process known as Rayleigh scattering while the similar process for scattering by particles that are similar or larger in wavelength is known as Mie scattering with the Tyndall effect being a commonly observed result. A small proportion of light scattering from atoms or molecules may undergo Raman scattering, wherein the frequency changes due to excitation of the atoms and molecules. Brillouin scattering occurs when the frequency of light changes due to local changes with time and movements of a dense material. Dispersion occurs when different frequencies of light have different phase velocities, due either


id: optics-20260505-7
file: data/en.wikipedia.org/wiki/Optics-7.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
In the leftmost figure above, the x and y components of the light wave are in phase. In this case, the ratio of their strengths is constant, so the direction of the electric vector (the vector sum of these two components) is constant. Since the tip of the vector traces out a single line in the plane, this special case is called linear polarisation. The direction of this line depends on the relative amplitudes of the two components. In the middle figure, the two orthogonal components have the same amplitudes and are 90° out of phase. In this case, one component is zero when the other component is at maximum or minimum amplitude. There are two possible phase relationships that satisfy this requirement: the x component can be 90° ahead of the y component or it can be 90° behind the y component. In this special case, the electric vector traces out a circle in the plane, so this polarisation is called circular polarisation. The rotation direction in the circle depends on which of the two-phase relationships exists and corresponds to right-hand circular polarisation and left-hand circular polarisation. In all other cases, where the two components either do not have


id: optics-20260505-8
file: data/en.wikipedia.org/wiki/Optics-8.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
Modern optics encompasses the areas of optical science and engineering that became popular in the 20th century. These areas of optical science typically relate to the electromagnetic or quantum properties of light but do include other topics. A major subfield of modern optics, quantum optics, deals with specifically quantum mechanical properties of light. Quantum optics is not just theoretical; some modern devices, such as lasers, have principles of operation that depend on quantum mechanics. Light detectors, such as photomultipliers and channeltrons, respond to individual photons. Electronic image sensors, such as CCDs, exhibit shot noise corresponding to the statistics of individual photon events. Light-emitting diodes and photovoltaic cells, too, cannot be understood without quantum mechanics. In the study of these devices, quantum optics often overlaps with quantum electronics. Specialty areas of optics research include the study of how light interacts with specific materials as in crystal optics and metamaterials. Other research focuses on the phenomenology of electromagnetic waves as in singular optics, non-imaging optics, non-linear optics, statistical optics, and radiometry. Additionally, computer engineers have taken an interest in integrated optics, machine vision, and photonic computing as possible components of the "next generation" of computers. Today, the pure science of optics is


id: optics-20260505-9
file: data/en.wikipedia.org/wiki/Optics-9.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
The human eye functions by focusing light onto a layer of photoreceptor cells called the retina, which forms the inner lining of the back of the eye. The focusing is accomplished by a series of transparent media. Light entering the eye passes first through the cornea, which provides much of the eye's optical power. The light then continues through the fluid just behind the cornea—the anterior chamber, then passes through the pupil. The light then passes through the lens, which focuses the light further and allows adjustment of focus. The light then passes through the main body of fluid in the eye—the vitreous humour, and reaches the retina. The cells in the retina line the back of the eye, except for where the optic nerve exits; this results in a blind spot. There are two types of photoreceptor cells, rods and cones, which are sensitive to different aspects of light. Rod cells are sensitive to the intensity of light over a wide frequency range, thus are responsible for black-and-white vision. Rod cells are not present on the fovea, the area of the retina responsible for central vision, and are not as responsive as cone cells to spatial and temporal changes


id: optics-20260505-10
file: data/en.wikipedia.org/wiki/Optics-10.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
Optical illusions (also called visual illusions) are characterized by visually perceived images that differ from objective reality. The information gathered by the eye is processed in the brain to give a percept that differs from the object being imaged. Optical illusions can be the result of a variety of phenomena including physical effects that create images that are different from the objects that make them, the physiological effects on the eyes and brain of excessive stimulation (e.g. brightness, tilt, colour, movement), and cognitive illusions where the eye and brain make unconscious inferences. Cognitive illusions include some which result from the unconscious misapplication of certain optical principles. For example, the Ames room, Hering, Müller-Lyer, Orbison, Ponzo, Sander, and Wundt illusions all rely on the suggestion of the appearance of distance by using converging and diverging lines, in the same way that parallel light rays (or indeed any set of parallel lines) appear to converge at a vanishing point at infinity in two-dimensionally rendered images with artistic perspective. This suggestion is also responsible for the famous moon illusion where the moon, despite having essentially the same angular size, appears much larger near the horizon than it does at zenith. This illusion so


id: optics-20260505-11
file: data/en.wikipedia.org/wiki/Optics-11.md
category: reference
title: Optics
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Optics
date_saved: 2026-05-05T09:33:17.531842+00:00
instance: kb-cron
parent: optics-20260505-0
summary:
where f {\displaystyle f} is the focal length, and D {\displaystyle D} is the diameter of the entrance pupil. By convention, "f/#" is treated as a single symbol, and specific values of f/# are written by replacing the number sign with the value. The two ways to increase the f-stop are to either decrease the diameter of the entrance pupil or change to a longer focal length (in the case of a zoom lens, this can be done by simply adjusting the lens). Higher f-numbers also have a larger depth of field due to the lens approaching the limit of a pinhole camera which is able to focus all images perfectly, regardless of distance, but requires very long exposure times. The field of view that the lens will provide changes with the focal length of the lens. There are three basic classifications based on the relationship to the diagonal size of the film or sensor size of the camera to the focal length of the lens: Normal lens: angle of view of about 50° (called normal because this angle considered roughly equivalent to human vision) and a focal length approximately equal to the diagonal of the film or sensor. Wide-angle


id: organicism-20260505-0
file: data/en.wikipedia.org/wiki/Organicism-0.md
category: reference
title: Organicism
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Organicism
date_saved: 2026-05-05T09:33:18.712548+00:00
instance: kb-cron
parent: organicism-20260505-0
summary:
Organicism is the philosophical position that states that the universe and its various parts (including human societies) ought to be considered alive and naturally ordered, much like a living organism. Vital to the position is the idea that organicistic elements are not dormant "things" per se but rather dynamic components in a comprehensive system that is, as a whole, everchanging. Organicism is related to but remains distinct from holism insofar as it prefigures holism; while the latter concept is applied more broadly to universal part-whole interconnections such as in anthropology and sociology, the former is traditionally applied only in philosophy and biology. Furthermore, organicism is incongruous with reductionism because of organicism's consideration of "both bottom-up and top-down causation". Regarded as a fundamental tenet in natural philosophy, organicism has remained a vital current in modern thought, alongside both reductionism and mechanism, that has guided scientific inquiry since the early 17th century. Though there remains dissent among scientific historians concerning organicism's pregeneration, most scholars agree on Ancient Athens as its birthplace. Surfacing in Athenian writing in the 4th-century BC, Plato was among the first philosophers to consider the universe an intelligent living (almost sentient) being, which he posits in his Philebus and


id: organicism-20260505-1
file: data/en.wikipedia.org/wiki/Organicism-1.md
category: reference
title: Organicism
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Organicism
date_saved: 2026-05-05T09:33:18.712548+00:00
instance: kb-cron
parent: organicism-20260505-0
summary:
== In theology == Organicism as a structuring or worldview motif finds implementation in the dogmatic theology of the nineteenth century. It was implemented prominently by Dutch Reformed theologian Herman Bavinck, and has been variously debated and appraised. Nonetheless, Bavinck's consideration of reality as both being and becoming, with an organic unity-and-diversity rooted in the united essence of the Trinity, stands as a prominent example of a theological implementation of organicism. Likewise, organicist language can be found in relation to faith and the church by Norwegian Lutheran theologian Gisle Johnson. Johnson construes the relationship between faith, church, and historical development as "an organic development", likening it to a sprout. For Gisle, systematic theology itself is an organic entity, a correlate of faith as principium cognoscendi where "the task is a systematic explication and reproduction of the content of faith-consciousness (Troesbevidsthedens), whereby the parts appear everywhere in their essential inner connection with the whole as an organism permeated and controlled by a definite principle." Prior to both of these theologians, organicism played an important role in the dogmatic construction of Danish dogmatician Hans Lassen Martensen. It is Martensen who provides a helpful and concise definition of organicism in its theological implementation:


id: organicism-20260505-2
file: data/en.wikipedia.org/wiki/Organicism-2.md
category: reference
title: Organicism
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Organicism
date_saved: 2026-05-05T09:33:18.712548+00:00
instance: kb-cron
parent: organicism-20260505-0
summary:
=== Ecology === In ecology, "organicism" and "organicistic" (or "organismic") are used to designate theories which conceptualize populations, particularly ecological communities or ecosystems, according to the model of the individual organism. As such, the term "organicism" is sometimes used interchangeably with "holism", although there are versions of holism that are not organicistic/organismic but individualistic. Early iterations of Gaia theory took an explicitly organicist approach by conceptualizing the entire Earth as an integrated, self-regulating organic whole akin to a living being, rather than just a mechanical collection of separate components. == See also == Holistic community Hylozoism Mechanical and organic solidarity Organic unity Organismic theory Orthogenesis Philosophy of organism Structural functionalism Structuralism (biology) == References == == Further reading == Barberis, Daniela S. (August 2003). "In Search of an Object: Organicist Sociology and the Reality of Society in Fin-De-Siècle France". History of the Human Sciences. 16 (3): 51–72. doi:10.1177/09526951030163004. S2CID 145751633. Beckner, Morton (1967) Organismic Biology, in "Encyclopedia of Philosophy," ed. Paul Edwards, MacMillan and The Free Press. Gilbert, Scott F.; Sarkar, Sahotra (September 2000). "Embracing complexity: organicism for the 21st century". Developmental Dynamics. 219 (1): 1–9. doi:10.1002/1097-0177(2000)9999:9999<::AID-DVDY1036>3.0.CO;2-A. PMID 10974666. S2CID 9452159. Haraway, Donna (1976). Crystals, Fabrics, and Fields: Metaphors That


id: panta-rhei-doctrine-20260505-0
file: data/en.wikipedia.org/wiki/Panta_rhei_(doctrine)-0.md
category: reference
title: Panta rhei (doctrine)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Panta_rhei_(doctrine)
date_saved: 2026-05-05T09:33:19.876174+00:00
instance: kb-cron
parent: panta-rhei-doctrine-20260505-0
summary:
The formula panta rhei (Ancient Greek: πάντα ῥεῖ, meaning "everything flows") is an aphorism which describes Heraclitus' doctrine. Plato attributes this teaching to Heraclitus in his dialogue Cratylus, but the formula first appears in the work of the late antique Neoplatonist Simplicius. This formulaic summary of Heraclitus' thought was already in use in Augustan times. Its Latin translation (cuncta fluunt) can be found in the 15th book of Metamorphoses in the "Speech of Pythagoras", in which Ovid sets out the natural philosophical foundation of his Metamorphoses. == Origin == Πάντα ῥεῖ is a formulaic summary of Heraclitus' thought, who flourished around 500BC. In his characterization of Heraclitus' cosmological theory, Plato has Socrates combine some of his best-known theorems: "Πάντα χωρεῖ καὶ οὐδὲν μένει", "everything moves and nothing stays" – with "all kinds of ancient wisdom, of course about Cronus and Rhea, which Homer had already said". He assumes that the name of the Titan, Rhea, can be traced back to the meaning of "to flow". The phrase is first found in literal form in Simplicius (born 490 – 560), a late antique commentator on the writings of Aristotle. == Flux doctrine == The fact that the phrase in the flux


id: participation-philosophy-20260505-0
file: data/en.wikipedia.org/wiki/Participation_(philosophy)-0.md
category: reference
title: Participation (philosophy)
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Participation_(philosophy)
date_saved: 2026-05-05T09:33:21.010107+00:00
instance: kb-cron
parent: participation-philosophy-20260505-0
summary:
In philosophy, participation is the inverse of inherence. == Overview == Accidents are said to inhere in substance. Substances, in turn, participate in their accidents. For example, the color red is said to inhere in the red apple. Conversely, the red apple participates in the color red. Participation also is predicated by analogy to a dependence relations between accidents. Thus an act may be said to participate in time in the sense that every act must occur at some time. In a similar way, color may be said to inhere in space, meaning that a color occurs only on the surface of a body—and thus only in space. Inherence, on the other hand, would not normally be predicated analogously of accidents. == See also == Substance theory == References == Doull, James (2001). "The Problem of Participation in Plato's Parmenides". Dionysius. XIX: 9–26.


id: philosophi-naturalis-principia-mathematica-20260505-0
file: data/en.wikipedia.org/wiki/Philosophiæ_Naturalis_Principia_Mathematica-0.md
category: reference
title: Philosophiæ Naturalis Principia Mathematica
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Philosophiæ_Naturalis_Principia_Mathematica
date_saved: 2026-05-05T09:33:22.278569+00:00
instance: kb-cron
parent: philosophi-naturalis-principia-mathematica-20260505-0
summary:
Philosophiæ Naturalis Principia Mathematica (English: The Mathematical Principles of Natural Philosophy), often called simply the Principia (), is a book by Sir Isaac Newton that expounds Newton's laws of motion and his law of universal gravitation. The Principia is written in Latin and comprises three volumes, and was authorized (imprimatur) by Samuel Pepys, then-President of the Royal Society on 5 July 1686 and first published in 1687. After annotating and correcting his personal copy of the first edition, Newton published two further editions, during 1713 with errors in the 1687 version corrected, and an improved version of 1726. The Principia forms a mathematical foundation for the theory of classical mechanics, and is generally considered to be one of the most important works in the history of science. It has been referred to as "the greatest scientific work in history" and "the supreme expression in human thought of the mind's ability to hold the universe fixed as an object of contemplation". In formulating his physical laws, Newton developed and used mathematical methods now included in the field of calculus, expressing them in the form of geometric propositions about "vanishingly small" shapes. In a revised conclusion to the Principia (see § General


id: philosophi-naturalis-principia-mathematica-20260505-1
file: data/en.wikipedia.org/wiki/Philosophiæ_Naturalis_Principia_Mathematica-1.md
category: reference
title: Philosophiæ Naturalis Principia Mathematica
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Philosophiæ_Naturalis_Principia_Mathematica
date_saved: 2026-05-05T09:33:22.278569+00:00
instance: kb-cron
parent: philosophi-naturalis-principia-mathematica-20260505-0
summary:
=== Book 2, part 2 of De motu corporum === Part of the contents originally planned for the first book was divided out into a second book, which largely concerns motion through resisting mediums. Just as Newton examined consequences of different conceivable laws of attraction in Book 1, here he examines different conceivable laws of resistance; thus Section 1 discusses resistance in direct proportion to velocity, and Section 2 goes on to examine the implications of resistance in proportion to the square of velocity. Through Book II, Newton was an important pioneer of fluid mechanics, and a later analysis showed that of its 53 propositions almost all are correct, with only two or three open to question. Book 2 discusses (in Section 5) hydrostatics and the properties of compressible fluids; he also derives Boyle's law (incorrectly; for an ideal gas is not like an elastic fluid). The effects of air resistance on pendulums are studied in Section 6, along with Newton's account of experiments that he carried out, to try to find out some characteristics of air resistance in reality by observing the motions of pendulums under different conditions. Newton compares the resistance offered by a medium against motions of


id: philosophi-naturalis-principia-mathematica-20260505-2
file: data/en.wikipedia.org/wiki/Philosophiæ_Naturalis_Principia_Mathematica-2.md
category: reference
title: Philosophiæ Naturalis Principia Mathematica
tags: science, encyclopedia
source_url: https://en.wikipedia.org/wiki/Philosophiæ_Naturalis_Principia_Mathematica
date_saved: 2026-05-05T09:33:22.278569+00:00
instance: kb-cron
parent: philosophi-naturalis-principia-mathematica-20260505-0
summary:
Only I must observe, that the vulgar conceive those quantities under no other notions but from the relation they bear to perceptible objects. And it will be convenient to distinguish them into absolute and relative, true and apparent, mathematical and common. ... instead of absolute places and motions, we use relative ones; and that without any inconvenience in common affairs; but in philosophical discussions, we ought to step back from our senses, and consider things themselves, distinct from what are only perceptible measures of them. To some modern readers it can appear that some dynamical quantities recognised today were used in the Principia but not named. The mathematical aspects of the first two books were so clearly consistent that they were easily accepted; for example, John Locke asked Christiaan Huygens whether he could trust the mathematical proofs and was assured about their correctness. However, the concept of an attractive force acting at a distance received a cooler response. In his notes, Newton wrote that the inverse square law arose naturally due to the structure of matter. However, he retracted this sentence in the published version, where he stated that the motion of planets is consistent with an inverse square law,


