Ludwik Fleck

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Fleck wrote that the development of truth in scientific research was an unattainable ideal as different researchers were locked into thought collectives (or thought-styles). This means "that a pure and direct observation cannot exist: in the act of perceiving objects the observer, i.e. the epistemological subject, is always influenced by the epoch and the environment to which he belongs, that is by what Fleck calls the thought style". [6] A "truth" was a relative value, expressed in the language or symbolism of the thought collective in which it belonged, and subject to the social and temporal structure of this collective. To state therefore that a specific truth is true or false is impossible. It is true in its own collective, but incomprehensible or unverifiable in most others. He felt that the development of scientific insights was not unidirectional and does not consist of just accumulating new pieces of information, but also in overthrowing the old ones. This overthrowing of old insights is difficult because a collective attains over time a specific way of investigating, bringing with it a blindness to alternative ways of observing and conceptualization. Change was especially possible when members of two thought collectives met and cooperated in observing, formulating hypothesis and ideas. He strongly advocated comparative epistemology. This approach anticipated later developments in social constructionism, and especially the development of critical science and technology studies.



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  1. Elena Aronova, Simone Turchetti (eds.), Science Studies during the Cold War and Beyond: Paradigms Defected, Palgrave Macmillan, 2016, p. 149: "some of [naukoznawstwo's] contributors (Kazimierz Twardowski, Maria Ossowska, Stanisław Ossowski, Tadeusz Kotarbiński, Kazimierz Ajdukiewicz, Florian Znaniecki, Ludwik Fleck, Stefan Amsterdamski) have gained international recognition."
  2. 1 2 Ludwik Fleck (Stanford Encyclopedia of Philosophy)
  3. Thomas S. Kuhn, The Structure of Scientific Revolutions . Chicago and London: University of Chicago Press, 1970 (2nd ed.), p. vi.
  4. Matthaus, Jürgen (2018). Predicting the Holocaust: Jewish Organizations Report from Geneva on the Emergence of the “Final Solution,” 1939–1942. Rowman & Littlefirled. p. 10.
  5. T. Tansey (2014) Typhus and tyranny, Nature 511(7509), 291.
  6. Siwecka, Sofia (2011). "Genesis and development of the "medical fact". Thought style and scientific evidence in the epistemology of Ludwik Fleck" (PDF). Dialogues in Philosophy, Mental and Neuro Sciences. 4 (2): 37–39.
Ludwik Fleck
Born(1896-07-11)July 11, 1896
DiedJune 5, 1961(1961-06-05) (aged 64)
Nationality Polish and Israeli
Known forContributions to logology [1]
Denkstil ("thought style") [2]
Denkkollektiv (thought collective)
Incommensurability (niewspółmierność) [2]
Academic background