Ludwik Fleck

Ludwik Fleck (11 July 1896 – 5 June 1961) was a Polish Jewish and Israeli physician and biologist who did important work in epidemic typhus in Lwów, Poland, with Rudolf Weigl and in the 1930s developed the concepts of the "Denkstil" ("thought style") and the "Denkkollektiv" ("thought collective"). The concept of the "thought collective" defined by him is important in the philosophy of science and in logology (the "science of science"), helping to explain how scientific ideas change over time, much as in Thomas Kuhn's later notion of the "paradigm shift" and in Michel Foucault's concept of the "episteme". His account of the development of facts at the intersection of active elements of the thought collective and the passive resistances of nature provides a way of considering the particular culture of modern science as evolutionary and evidence-oriented.