Thought style and thought collective are two well-known concepts from Ludwik Fleck’s theory of science, which he originally formulated in Polish and German. This paper contends that these two concepts cannot be fully understood without a third—Stimmung/nastrój, which is one of the musical metaphors that play an important role in Fleck’s thinking. Because it is most often translated into English as “mood”, Fleck’s musical metaphors are mostly lost in translation, appearing as mere rhetoric. Only if and when we understand Stimmung/nastrój (...) in the musical meaning of attunement, we can fully understand thought collectives, for which Stimmung/nastrój is sine qua non, and thought style, which appears if and when a collective turns out to be an enduring and not a momentary one. (shrink)