 (2) In the interwar period Poland was probably the only country where faculties of medicine had chairs for the philosophy and history of medicine (Löwy 1990). Between 1908 and 1919 Władysław Szumowski taught the history of medicine in Lvov. Fleck also had some professional contact with two philosophers and historians of medicine, Włodzimierz Sieradzki and Witold Ziembicki. He was a friend of Jakób Frostig, a philosophizing psychiatrist. It is worth mentioning a few remarks from Frostig’s Das schizophrene Denken. Phänomenologische Studien zum Problem der widersinnigen Sätze (Leipzig 1929), which can be seen almost without any change among those written by Fleck: “We mean by [the expression ‘social group’] any group of people bound together by a common ‘intention’. Thus the group of mathematicians is a group of a very special, mathematical mentality. (…) one and the same person can (…) belong to several very different human groups.  (…) the group’s collective storehouse ever changes and with it the criteria for truth. (…) It is only in relation to the collective stores of the group in question that we can denote a state of affairs as correct or as a personal error” (following Schnelle 1986, p. 9). However, Fleck does not mention any of these scholars in his writings, even though they created the thought style and intellectual mood that, according to his views, were necessary for his sociology and philosophy of science to emerge. 