---
title: "Science in classical antiquity"
chunk: 4/6
source: "https://en.wikipedia.org/wiki/Science_in_classical_antiquity"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:38:50.555898+00:00"
instance: "kb-cron"
---

The military campaigns of Alexander the Great spread Greek thought to Egypt, Asia Minor, Persia, up to the Indus River. The resulting migration of many Greek speaking populations across these territories provided the impetus for the foundation of several seats of learning, such as those in Alexandria, Antioch, and Pergamum.
Hellenistic science differed from Greek science in at least two respects: first, it benefited from the cross-fertilization of Greek ideas with those that had developed in other non-Hellenic civilizations; secondly, to some extent, it was supported by royal patrons in the kingdoms founded by Alexander's successors. The city of Alexandria, in particular, became a major center of scientific research in the 3rd century BC. Two institutions established there during the reigns of Ptolemy I Soter (367–282 BC) and Ptolemy II Philadelphus (309–246 BC) were the Library and the Museum. Unlike Plato's Academy and Aristotle's Lyceum, these institutions were officially supported by the Ptolemies, although the extent of patronage could be precarious depending on the policies of the current ruler.
Hellenistic scholars often employed the principles developed in earlier Greek thought in their scientific investigations, such as the application of mathematics to phenomena or the deliberate collection of empirical data. The assessment of Hellenistic science, however, varies widely. At one extreme is the view of English classical scholar Cornford, who believed that "all the most important and original work was done in the three centuries from 600 to 300 BC". At the other end is the view of Italian physicist and mathematician Lucio Russo, who claims that the scientific method was actually born in the 3rd century BC, only to be largely forgotten during the Roman period and not revived again until the Renaissance.

=== Technology ===

A good example of the level of achievement in astronomical knowledge and engineering during the Hellenistic age can be seen in the Antikythera mechanism (150–100 BC). It is a 37-gear mechanical computer which calculated the motions of the Sun, Moon, and possibly the other five planets known to the ancients. The Antikythera mechanism included lunar and solar eclipses predicted on the basis of astronomical periods believed to have been learned from the Babylonians. The device may have been part of an ancient Greek tradition of complex mechanical technology that was later, at least in part, transmitted to the Byzantine and Islamic worlds, where mechanical devices which were complex, albeit simpler than the Antikythera mechanism, were built during the Middle Ages. Fragments of a geared calendar attached to a sundial, from the fifth or sixth century Byzantine Empire, have been found; the calendar may have been used to assist in telling time. A geared calendar similar to the Byzantine device was described by the scientist al-Biruni around 1000, and a surviving 13th-century astrolabe also contains a similar clockwork device.

=== Medicine ===

An important school of medicine was formed in Alexandria from the late 4th century to the 2nd century BC. Beginning with Ptolemy I Soter, medical officials were allowed to cut open and examine cadavers for the purposes of learning how human bodies operated. The first use of human bodies for anatomical research occurred in the work of Herophilos (335–280 BC) and Erasistratus (c. 304 – c. 250 BC), who gained permission to perform live dissections, or vivisections, on condemned criminals in Alexandria under the auspices of the Ptolemaic dynasty.
Herophilos developed a body of anatomical knowledge much more informed by the actual structure of the human body than previous works had been. He also reversed the longstanding notion made by Aristotle that the heart was the "seat of intelligence", arguing for the brain instead. Herophilos also wrote on the distinction between veins and arteries, and made many other accurate observations about the structure of the human body, especially the nervous system. Erasistratus differentiated between the function of the sensory and motor nerves, and linked them to the brain. He is credited with one of the first in-depth descriptions of the cerebrum and cerebellum. For their contributions, Herophilos is often called the "father of anatomy", while Erasistratus is regarded by some as the "founder of physiology".

=== Mathematics ===

Greek mathematics in the Hellenistic period reached a level of sophistication not matched for several centuries afterward, as much of the work represented by scholars active at this time was of a very advanced level. There is also evidence of combining mathematical knowledge with high levels of technical expertise, as found for instance in the construction of massive building projects (e.g., the Syracusia), or in Eratosthenes' (276–195 BC) measurement of the distance between the Sun and the Earth and the size of the Earth.
Although few in number, Hellenistic mathematicians actively communicated with each other; publication consisted of passing and copying someone's work among colleagues. Among the most recognizable is the work of Euclid (325–265 BC), who presumably authored a series of books known as the Elements, a canon of geometry and elementary number theory for many centuries. Euclid's Elements served as the main textbook for the teaching of theoretical mathematics until the early 20th century.
Archimedes (287–212 BC), a Sicilian Greek, wrote about a dozen treatises where he communicated many remarkable results, such as the sum of an infinite geometric series in Quadrature of the Parabola, an approximation to the value π in Measurement of the Circle, and a nomenclature to express very large numbers in the Sand Reckoner.
The most characteristic product of Greek mathematics may be the theory of conic sections, which was largely developed in the Hellenistic period, primarily by Apollonius (262–190 BC). The methods used made no explicit use of algebra, nor trigonometry, the latter appearing around the time of Hipparchus (190–120 BC).

=== Astronomy ===