Let's think about the intellectual influences that have shaped philosophers of science over the past one hundred years or so: Vienna Circle empiricism, logical positivism, the deductive-nomological method, the Kuhn-Lakatos revolution, incorporation of the sociology of science into philosophy of science, a surge of interest in scientific realism, and an increasing focus on specific areas of science as objects of philosophy of science investigations. And along these waypoints it would be fairly easy to place a few road signs indicating the major philosophers associated with each phase in the story -- Ayer, Carnap, Reichenbach, Hempel, Nagel, Hanson, Hesse, Kuhn, Lakatos, Putnam, Boyd, Quine, Sellars, Bhaskar, Sober, Rosenberg, Hausman, Epstein ...
So we might get the idea that we've got a pretty good idea of the "space" in which philosophy of science questions should be posed, along with a sense of the direction of change and progress that has occurred in the field since 1930. The philosophy of science is a "tradition" within philosophy, and we who practice in the field have a sense of understanding its geography.
But now I suggest that readers examine Wojciech Sady's excellent article on Ludwik Fleck in the Stanford Encyclopedia of Philosophy (link). Fleck (1896-1961) was a Polish-Jewish scientist and medical researcher who wrote extensively in the 1930s about "social cognition" and what we would now call the sociology of science. His biography is fascinating and harrowing; he and his family survived life in Lvov under the Soviet Union (1939-1941) after the simultaneous invasion of Poland by Germany and the USSR; occupation, pogroms, and capture by the Germans in Lvov; resettlement in the Lvov ghetto; transport to Auschwitz and later Buchenwald; and survival throughout, largely because of his scientific expertise on typhus vaccination. Fleck survived to serve as a senior academic scientist in Lublin. In 1957 Fleck and his wife emigrated to Israel, where their son had settled.
Fleck is not entirely unknown to philosophers today, but it's a close call. A search for articles on Fleck in a research university search engine produces about 2,500 academic articles; by comparison, the same search results in 183,000 articles on Thomas Kuhn. And I suspect that virtually no philosopher with a PhD from a US department of philosophy since 1970 and with a concentration in the philosophy of science has ever heard of Fleck. 100% of those philosophers, of course, will have a pretty good idea of Kuhn's central ideas. And yet Fleck has a great deal in common with Kuhn -- some three decades earlier. More importantly, many of Fleck's lines of thought about the history of concepts of disease in medicine are still enormously stimulating, and they represent potential sources of innovation in the field today. Fleck asked very original and challenging questions about the nature of scientific concepts and knowledge. Thomas Kuhn was one of the few historians of science who were aware of Fleck's work, and he wrote a very generous introduction to the English translation of Fleck's major book in the sociology and history of science, Genesis and Development of a Scientific Fact (1979/1935).
Here are Fleck's central ideas, as summarized by Sady. Understanding the world around us (cognition) is a collective project. Individuals interacting with each other about some aspect of the world constitute a "thought collective" -- "a community of persons mutually exchanging ideas or maintaining intellectual interaction" (Sady, sect. 3). A thought collective forms a vocabulary and crafts a set of concepts that are mutually understood within the group, but misunderstood by persons outside the group. A "thought collective" forms a "collective bond" -- a set of emotions of loyalty and solidarity which Fleck describes as a "collective mood". There are no "objective facts"; rather, facts are defined by the terms and constructs of the "thought collective". And the perceptions, beliefs, and representations of different "thought collectives" concerned with ostensibly the same subject matter are incommensurable.
So it is not possible to compare a theory with “reality in itself”. It is true that those who use a thought style give arguments for their views, but those arguments are of restricted value. Any attempt to legitimize a particular view is inextricably bound to standards developed within a given style, and those who accept those standards accept also the style. (Sady, sect. 7)
And scientific knowledge is entirely conditional upon the background structure of the "thought collective" or conceptual framework of the research community:
As Fleck states in the last sentence of (1935b), “'To see’ means: to recreate, at a suitable moment, a picture created by the mental collective to which one belongs”. (Sady, sect. 5)
Thus, it is impossible to see something radically new “simply and immediately”: first the constrains of an old thought style must be removed and a new style must emerge, a collective's thought mood must change— and this takes time and work with others. (Sady, sect. 5)
These ideas plainly correspond closely to Imre Lakatos's idea of a research community and Thomas Kuhn's idea of a paradigm. They stand in striking contrast to the logical positivism of the Vienna Circle being developed at roughly the same time. (And yet Sady notes that Moritz Schlick offered to recommend publication of Genesis and Development of a Scientific Fact in 1934.)
Upon first exposure to Fleck's ideas from the Sady article I initially assumed that Fleck was influenced by Communist ideas about science and knowledge (as were Polish sociologists and philosophers in the 1950s). The "collective thoughts" that are central to Fleck's account of the history of science sound a lot like Engels or Lenin. And yet this turns out not to be the case. Nothing in Sady's article suggests that Fleck was influenced by Polish Communist theory in the 1920s and 1930s. Instead, his ideas about social cognition seem to develop out of a largely central European tradition of thinking about thinking. According to Sady, Fleck's own "thought collectives" (research traditions) included: (1) medical research; (2) the emerging field in Poland of history of medicine (Władysław Szumowski, Włodzimierz Sieradzki, and Witold Ziembicki); (3) the Polish "philosophical branch" of mathematical-philosophical school (minor); (4) sociology of knowledge (Levy-Bruhl, Wilhelm Jerusalem; but not Max Scheler or Karl Mannheim; also minor). Sady also emphasizes Fleck's interest in the debates that were arising in physics around the puzzles of quantum mechanics and relativity theory.
So there is a major irony here: one of Fleck's central ideas is that individual thinkers can achieve nothing by themselves as individuals. And yet Fleck's ideas as developed in his history of the medical concept of syphilis appear to be largely self-generated -- the results of his own knowledge and reflection. The advocate of the necessity of "thought collectives" was himself not deeply integrated into any coherent thought collective.
This story has an important moral. Most importantly, it confirms to me that there are always important perspectives on a given philosophical topic that have fallen outside the mainstream and may be forever forgotten. This suggests the value, for philosophers and other scholars interested in arriving at valuable insights into difficult problems, of paying attention to the paths not taken in previous generations. There is nothing in the nature of academic research that guarantees that "the best ideas of a generation will become part of the canon for the next generation"; instead, many good and original ideas have been lost to the disciplines through bad luck. This is largely true of Fleck.
But here is another, more singular fact that is of interest. How did Sady's article, and therefore Fleck himself, come to my attention? The answer is that in the past year I've been reading a lot about Polish and Jewish intellectuals from the 1930s with growing fascination because of a growing interest in the Holocaust and the Holodomor. That means a lot of searches on people like Janina Bauman, Leszek Kołakowski, and Vasily Grossman. I've searched for the histories of places like Lvov, Galicia, and Berdichev. And in the serendipity of casting a wide net, I've arrived at the happy experience of reading Sady's fascinating article, along with some of Fleck's important work.
Here is the prologue to Fleck's Genesis and Development of a Scientific Fact. It expresses very concisely Fleck's perspective on science, concepts, and facts.
What is a fact?
A fact is supposed to be distinguished from transient theories as something definite, permanent, and independent of any subjective interpretation by the scientist. It is that which the various scientific disciplines aim at. The critique of the methods used to establish it constitutes the subject matter of epistemology.
Epistemology often commits a fundamental error: almost exclusively it regards well-established facts of everyday life, or those of classical physics, as the only ones that are reliable and worthy of investigation. Valuation based upon such an investigation is inherently naive, with the result that only superficial data are obtained.
Moreover, we have even lost any critical insight we may once have had into the organic basis of perception, taking for granted the basic fact that a normal person has two eyes. We have nearly ceased to consider this as even knowledge at all and are no longer conscious of our own participation in perception. Instead, we feel a complete passivity in the face of a power that is independent of us; a power we call “existence” or “reality.” In this respect we behave like someone who daily performs ritual or habitual actions mechanically. These are no longer voluntary activities, but ones which we feel compelled to perform to the exclusion of others. A better analogy perhaps is the behavior of a person taking part in a mass movement. Consider, for instance, a casual visitor to the Stock Exchange, who feels the panic selling in a bear market as only an external force existing in reality. He is completely unaware of his own excitement in the throng and hence does not realize how much he may be contributing to the general state. Long-established facts of everyday life, then, do not lend themselves to epistemological investigation.
As for the facts of classical physics, here too we are handicapped by being accustomed to them in practice and by the facts themselves being well worn theoretically. I therefore believe that a “more recent fact,” discovered not in the remote past and not yet exhausted for epistemological purposes, will conform best to the principles of unbiased investigation. A medical fact, the importance and applicability of which cannot be denied, is particularly suitable, because it also appears to be very rewarding historically and phenomenologically. I have therefore selected one of the best established medical facts: the fact that the so-called Wassermann reaction is related to syphilis.
HOW, THEN, DID THIS EMPIRICAL FACT ORIGINATE AND IN WHAT DOES IT CONSIST?
Lvov, Poland, summer 1934