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title: "International Encyclopedia of Unified Science"
chunk: 1/1
source: "https://en.wikipedia.org/wiki/International_Encyclopedia_of_Unified_Science"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T04:36:50.048664+00:00"
instance: "kb-cron"
---

The International Encyclopedia of Unified Science (IEUS) was a series of publications devoted to unified science. The IEUS was conceived at the Mundaneum Institute in The Hague in the 1930s, and published in the United States beginning in 1938. It was an ambitious project that was never completed.
The IEUS was an output of the Vienna Circle to address the "growing concern throughout the world for the logic, the history, and the sociology of science..." Only the first section Foundations of the Unity of Science (FUS) was published; it contains two volumes for a total of nineteen monographs published from 1938 to 1969.


== International Congresses for the Unity of Science ==

Creation of the IEUS was facilitated by the International Congresses for the Unity of Science organized by members of the Vienna Circle. After a preliminary conference in Prague in 1934, the First International Congress for the Unity of Science was held at the Sorbonne, Paris, 16–21 September 1935. It was attended by about 170 people from over twenty different countries. With the active involvement of Kazimierz Ajdukiewicz (Poland), Susan Stebbing (England), and Federigo Enriques (Italy) the scope of the project for an IEUS was considerably expanded. The congress expressed its approval of the planned IEUS as proposed by the Mundaneum, and further set up a committee to plan future congresses. This committee included the following members:

The Third International Congress for the Unity of Science, which was devoted exclusively to the IEUS, was held in Paris, 29–31 July 1937.


== Volume I ==
Encyclopedia and Unified Science (FUS I-1)
Otto Neurath, Niels Bohr, John Dewey, Bertrand Russell, Rudolf Carnap, and Charles Morris
Foundations of the Theory of Signs (FUS I-2)
Charles Morris
Foundations of Logic and Mathematics (FUS I-3)
Rudolf Carnap
Linguistic Aspects of Science (FUS I-4)
Leonard Bloomfield
Procedures of Empirical Science (FUS I-5)
Victor F. Lenzen
Principles of the Theory of Probability (FUS I-6) 
Ernest Nagel
Foundations of Physics (FUS I-7) 
Philipp Frank
Cosmology (FUS I-8) 
E. Finlay-Freundlich
Foundations of Biology (FUS I-9) 
Felix Mainx
The Conceptual Framework of Psychology (FUS I-10) 
Egon Brunswik


== Volume II ==
Foundations of the Social Sciences (FUS II-1)
Otto Neurath
The Structure of Scientific Revolutions (FUS II-2)
Thomas S. Kuhn
Science and the Structure of Ethics (FUS II-3)
Abraham Edel
Theory of Valuation (FUS II-4)
John Dewey
The Technique of Theory Construction (FUS II-5)
Joseph H. Woodger
Methodology of Mathematical Economics and Econometrics (FUS II-6) 
Gerhard Tintner
Concept Formation in Empirical Science (FUS II-7) 
Carl G. Hempel
The Development of Rationalism and Empiricism (FUS II-8) 
George De Santillana, Edgar Zilsel
The Development of Logical Empiricism (FUS II-9) 
Joergen Joergensen
Bibliography and Index (FUS II-10) 
Herbert Feigl, Charles Morris


== Influence ==
Historian David Hollinger argued that the IEUS was a less comprehensive account of the sciences of the time than it could have been, and was especially weak in the social sciences. Hollinger noted that the Encyclopaedia of the Social Sciences, published around the same time, provided a much more comprehensive account of the social sciences: "The Encyclopedia of the Social Sciences (12 vols., New York, 1933–1937) was a prodigious endeavor brought to successful completion by Alvin Johnson. This encyclopedia is a much more important episode in the history of thought than The International Encyclopedia of Unified Science yet has attracted much less attention from historians than the abortive enterprise led by Neurath." Hollinger also said that the scholarly journal Philosophy of Science, founded in 1934, provided a much more inclusive perspective on the sciences in those years than did the IEUS.


== See also ==
Encyclopedism
Van Nostrand's Scientific Encyclopedia –  published in 1938, the same year as the first monograph in the IEUS
World Brain –  published in 1938, the same year as the first monograph in the IEUS
World Congress of Universal Documentation –  held in Paris in 1937 a few weeks after the Third International Congress for the Unity of Science


== References ==


== Further reading ==
Morris, Charles W. (1962) [1960]. "On the history of the International Encyclopedia of Unified Science". Logic and language: studies dedicated to Professor Rudolf Carnap on the occasion of his seventieth birthday. Synthese library. Dordrecht: D. Reidel. pp. 242–246. doi:10.1007/978-94-017-2111-0_16. ISBN 9789048183197. JSTOR 20114366. OCLC 23127209. {{cite book}}: ISBN / Date incompatibility (help)
Nemeth, Elisabeth; Stadler, Friedrich, eds. (1996). Encyclopedia and utopia: the life and work of Otto Neurath (1882–1945). Vienna Circle Institute yearbook. Vol. 4. Dordrecht; Boston: Kluwer Academic Publishers. ISBN 0792341619. OCLC 36219438.
Neurath, Otto (1983) [1936]. "Encyclopedia as 'model'". In Cohen, Robert S.; Neurath, Marie; Fawcett, Carolyn R. (eds.). Philosophical papers, 1913–1946. Vienna Circle collection. Vol. 16. Dordrecht; Boston: D. Reidel. pp. 145–158. doi:10.1007/978-94-009-6995-7_13. ISBN 9027714835.
O'Neill, John (September 2003). "Unified science as political philosophy: positivism, pluralism and liberalism". Studies in History and Philosophy of Science Part A. 34 (3): 575–596. doi:10.1016/S0039-3681(03)00048-7.
Pombo, Olga (2011). "Neurath and the encyclopaedic project of unity of science". In Symons, John; Pombo, Olga; Torres, Juan Manuel (eds.). Otto Neurath and the unity of science. Logic, epistemology and the unity of science. Vol. 18. Dordrecht; New York: Springer Verlag. pp. 59–70. doi:10.1007/978-94-007-0143-4_5. ISBN 9789400701427. OCLC 723045353.
Potochnik, Angela (May 2011). "A Neurathian conception of the unity of science" (PDF). Erkenntnis. 74 (3): 305–319. doi:10.1007/s10670-010-9228-0.
Reisch, George A. (June 1994). "Planning science: Otto Neurath and the International Encyclopedia of Unified Science". The British Journal for the History of Science. 27 (2): 153–175. doi:10.1017/S0007087400031873. JSTOR 4027433.
Zolo, Danilo (1989) [1986]. "The unity of science as a historico-sociological goal: from the primacy of physics to the epistemological priority of sociology". Reflexive epistemology: the philosophical legacy of Otto Neurath. Boston studies in the philosophy of science. Vol. 118. Dordrecht; Boston: Kluwer Academic Publishers. pp. 83–106. doi:10.1007/978-94-009-2415-4_5. ISBN 0792303202. OCLC 19814200.