Ludwik Fleck


Fleck is today widely recognized as a pioneer of the constructivist-relativist trend in philosophy of science and of the sociologically-oriented approach to the study of the evolution of scientific and medical knowledge. He deserves this recognition and respect all the more as during his lifetime his philosophical achievement passed completely unnoticed.The well known historian of scienceThomas Kuhn recognized Fleck's main work as a source of inspiration of his The Structure of Scientific Revolution. But Fleck was not, however, trained as an historian, or a philosopher, or a sociologist; he was a physician and worked on serology, bacteriology, and leukergy (the name was introduced by him to denote the increase in the viscosity of leucocytes as a result of inflammation). But, apart from his specialist medical studies, he was interested in history, philosophy and sociology of science and was influenced by seminal ideas proposed by the founders of the Polish School of Medicine.


Ludwik Fleck was born in Lvov (Poland) on July 11, 1896, and grew up in the relatively extensive cultural autonomy of Galicia in the Austrian-occupied territory. He gradued from the Polish Lyceum in 1914 and he enrolled at the Jan Kazimierz  University of Lvov , where he received his medical degree. Even when he was a student, Fleck was particularly interested in the problems of microbiological research. In 1920 he became an assistant of the famous typhus specialist Rudolf Weigl in Przemysl and followed him when he was appointed to the chair in Biology at the medical school of the Univ. of Lvov in 1921, where Fleck remained until 1923. From then to 1939 he was not able to return to a university position and worked at first in the Department of Internal Medicine of the General Hospital in Lvov and then became Director of the Bacteriological Laboratory of the local social assurance authority. From 1935 on, he worked only in the private bacteriological laboratory which he had founded in 1923.
With the outbreak of Word War II Lvov became a Soviet. The medical school of the university became an independent college, the Ukrainian Medical Institute, and Fleck was appointed teacher and director of the Microbiological Department. With Nazi Germany's attack on the Soviet Union and the German occupation of Lvov, Fleck was forced to vacate these positions and was deported with his wife, Ernestina Waldman, and son Ryszard to the city's Jewish ghetto; here Fleck continued his research in the hospital, where he developed a new procedure in which he procured vaccine from the urine of typhus patients. Fleck's work was also known to the German occupiers; for this reason Fleck and his family were arrested in December, 1942 and deported to the "Laokoon" pharmaceutical factory: his work consisted in producing typhus serum. At the end of January, he and his family were arrested again and sent to the Auschwitz concentration camp on February 7, 1943, where he worked at the Hygienic Institute of Block 10; his task was to diagnose syphilis, typhus and other illnesses using serological tests. From December 1943 until the liberation on April 11, 1945, Fleck was detained in Buchenwald, where a laboratory was set up in Block 50 at the Hygiene Institute of the SS for the production and the study of production methods for typhus serum.
His post-war life began in Lublin where between 1945 and 1952 he served as the head of the Institute of Microbiology of the School of Medicine of
Maria Sklodowska-Curie University of Lublin . In 1952 he moved to Warsaw where he became the Director of the Department of Microbiology and Immunology at the Mother and Child State Institute. In 1954 he was elected a member of the Polish Academy of Sciences. At the heart of Fleck's research during these years was the question of the behavior of leucocytes in infectious and stress situations. The years between 1946 and 1957 were the period of Fleck's most intensive medical research: he directed approximately 50 doctoral dissertations and published 87 medical and scientific articles, in Polish, French, English and Swiss journals. He travelled for congresses and lectures to Denmark, France, the U.S.S.R., the U.S.A. and Brazil. In 1951 Fleck was awarded the National Prize for Scientific Achievements, second degree; in 1955 he was distinguished with the Officer's Cross of the Order of the Renaissance of Poland.
In 1956, after a heart attack and the discovery that he was suffering from lymphosarcoma, Fleck decided emigrate to Israel in order that he and his wife could again live close to his son, who had been living in Palestine since the end of the war. In Israel a position was created for Fleck at the Israel Institute for Biological Research in Ness-Ziona, where he died on 5 July 1961, at the age of 64, of a second heart attack.

Main works

A complete biblography on Fleck's thought, prepared by T. Schnelle, is contained in the volume ed. by R.S. Cohen and T. Schnelle, Cognition and fact - Materials on Ludwik Fleck, Dordrecht, Reidel 1986, pp. 445-457.

- Genesis and Development of a Scientific Fact, Ed. by. T.J. Trenn and R.K. Merton, Chicago/London, 1979 (first edition: Entstehung und Entwicklung einer wissenschaftlichen Tatsache? Einfürung in die Leher vom Denkstil und Denkkollektiv, B. Schwabeund Co., Verlabuchhndlung, Basel, 1935.
- Erfahrung und Tatasache. Gesammelte Aufsätze, Suhrkamp Verlag, Frankfurt a.M., 1989.

Seven Fleck's papers are also published in R.S. Cohen and T. Schnelle (eds.), Cognition and Fact - Materials on Ludwik Fleck, op. cit., pp. 39-158: "Some Specific Features of the Medical Way of Thinking" (1929), "On the Crisis of 'Reality'" (1929), "Scientific Observation and Perception in general" (1935), "The Problem of Epistemology" (1936), "Problems of the Science of Science" (1946), "To Look, To See, To Know" (1947), "Crisis in Science" (unpublished, 1960).

Selected Bibliography

- Papers written by N. Rotenstreich, J. Giedymin, B. Wolniewicz, W. Markiewicz, T. Schnelle, S. Toulmin, P.A. Heelan, Y. Elkana, D. Wittich, S. Shapin, D. Bloor, B. Zalc, A.M. Moulin, I. Löwy in R.S. Cohen and T. Schnelle (eds.), Cognition and Fact - Materials on Ludwik Fleck, op. cit.
- P. Rossi, "Fatti scientifici e stili di pensiero: appunti intorno a una rivoluzione immaginaria", Rivista di Filosofia, 72 (1981), pp.402-428.
- T. Schnelle, Ludwik Fleck - Leben und Denken. Zur Entstehung und Entwicklung des soziologischen Denkstils in der Wissenschaftphilosophie, Hochschulverlg, Freiburg, 1982.
- Z. Cackowski, "Ludwik Fleck's epistemology", Dialectics and Humanism, 3, 1982, pp. 11-23.
- I. Löwy, The Scientific Roots of Constructivist Epistemologies: Hélène Metzger and Ludwik Fleck, in G. Freudenthal (ed.), Etudes sur Hélène Metzger, Corpus, Paris 1986, pp. 219-235.
- J. Wettersten, "The Fleck Affair: Fashions v. Heritage", Inquiry, v. 34, n. 4, 1991.


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