Popper on “Crusonian science” in The Open Society and Its Enemies (1945), a particularly vivid and memorable illustration of what has become a central area of research in academic philosophy:
Two aspects of the method of the natural sciences are of importance in this connection. Together they constitute what I may term the ‘public character of scientific method’. First, there is something approaching free criticism. A scientist may offer his theory with the full conviction that it is unassailable. But this will not impress his fellow-scientists and competitors; rather it challenges them: they know that the scientific attitude means criticizing everything, and they are little deterred even by authorities. Secondly, scientists try to avoid talking at cross-purposes. (I may remind the reader that I am speaking of the natural sciences, but a part of modern economics may be included.) They try very seriously to speak one and the same language, even if they use different mother tongues. In the natural sciences this is achieved by recognizing experience as the impartial arbiter of their controversies. When speaking of ‘experience’ I have in mind experience of a ‘public’ character, like observations, and experiments, as opposed to experience in the sense of more ‘private’ aesthetic or religious experience; and an experience is ‘public’ if everybody who takes the trouble can repeat it. In order to avoid speaking at cross-purposes, scientists try to express their theories in such a form that they can be tested, i.e. refuted (or else corroborated) by such experience.
This is what constitutes scientific objectivity. Everyone who has learned the technique of understanding and testing scientific theories can repeat the experiment and judge for himself. In spite of this, there will always be some who come to judgements which are partial, or even cranky. This cannot be helped, and it does not seriously disturb the working of the various social institutions which have been designed to further scientific objectivity and criticism; for instance the laboratories, the scientific periodicals, the congresses. This aspect of scientific method shows what can be achieved by institutions designed to make public control possible, and by the open expression of public opinion, even if this is limited to a circle of specialists. Only political power, when it is used to suppress free criticism, or when it fails to protect it, can impair the functioning of these institutions, on which all progress, scientific, technological, and political, ultimately depends.
In order to elucidate further still this sadly neglected aspect of scientific method, we may consider the idea that it is advisable to characterize science by its methods rather than by its results. Let us first assume that a clairvoyant produces a book by dreaming it, or perhaps by automatic writing. Let us assume, further, that years later as a result of recent and revolutionary scientific discoveries, a great scientist (who has never seen that book) produces one precisely the same. Or to put it differently we assume that the clairvoyant ‘saw’ a scientific book which could not then have been produced by a scientist owing to the fact that many relevant discoveries were still unknown at that date. We now ask : is it advisable to say that the clairvoyant produced a scientific book? We may assume that, if submitted at the time to the judgement of competent scientists, it would have been described as partly ununderstandable, and partly fantastic; thus we shall have to say that the clairvoyant’s book was not when written a scientific work, since it was not the result of scientific method. I shall call such a result, which, though in agreement with some scientific results, is not the product of scientific method, a piece of ‘revealed science’.
In order to apply these considerations to the problem of the publicity of scientific method, let us assume that Robinson Crusoe succeeded in building on his island physical and chemical laboratories, astronomical observatories, etc., and in writing a great number of papers, based throughout on observation and experiment. Let us even assume that he had unlimited time at his disposal, and that he succeeded in constructing and in describing scientific systems which actually coincide with the results accepted at present by our own scientists. Considering the character of this Crusonian science, some people will be inclined, at first sight, to assert that it is real science and not ‘revealed science’. And, no doubt, it is very much more like science than the scientific book which was revealed to the clairvoyant, for Robinson Crusoe applied a good deal of scientific method. And yet, I assert that this Crusonian science is still of the ‘revealed’ kind; that there is an element of scientific method missing, and consequently, that the fact that Crusoe arrived at our results is nearly as accidental and miraculous as it was in the case of the clairvoyant. For there is nobody but himself to check his results; nobody but himself to correct those prejudices which are the unavoidable consequence of his peculiar mental history; nobody to help him to get rid of that strange blindness concerning the inherent possibilities of our own results which is a consequence of the fact that most of them are reached through comparatively irrelevant approaches. And concerning his scientific papers, it is only in attempts to explain his work to somebody who has not done it that he can acquire the discipline of clear and reasoned communication which too is part of scientific method. In one point—a comparatively unimportant one—is the ‘revealed’ character of the Crusonian science particularly obvious; I mean Crusoe’s discovery of his ‘personal equation’ (for we must assume that he made this discovery), of the characteristic personal reaction-time affecting his astronomical observations. Of course it is conceivable that he discovered, say, changes in his reaction-time, and that he was led, in this way, to make allowances for it. But if we compare this way of finding out about reaction-time, with the way in which it was discovered in ‘public’ science—through the contradiction between the results of various observers—then the ‘revealed’ character of Robinson Crusoe’s science becomes manifest.
To sum up these considerations, it may be said that what we call ‘scientific objectivity’ is not a product of the individual scientist’s impartiality, but a product of the social or public character of scientific method; and the individual scientist’s impartiality is, so far as it exists, not the source but rather the result of this socially or institutionally organized objectivity of science.
A historically minded philosophy syllabus on this subject—what has been meant by the “social character” of knowledge—might run through Socratic dialogue; Descartes on self-knowledge; Hegel and the dialectical turn; Freud and the psychoanalytic turn (as rupture of Cartesianism); Marx and the ideological turn (as rupture of autonomous liberal subject); Peirce, Dewey, and other pragmatists on communities of inquiry; Kuhn, Lakatos, and midcentury philosophy of science (normal science, research programs); more contemporary logical puzzles over private language, self-knowledge, and common knowledge; externalism in epistemology, philosophy of language, and philosophy of mind; social construction and the science wars (post-Sokal); Foucault, Ian Hacking, and historical ontology; the careers of “social epistemology” (compare “standpoint epistemology”) as new research programs; the rise of sociology and especially political economy of science; epistemic scrutiny of mathematical practice and new anxieties over mathematical knowledge (post-Four Color Theorem); and contemporary work on democracy and epistemology.
Writ large, this story is often as much about the self as it is about knowledge. On one side there is inwardness, individuality, privacy, personality, property, logic, and pure reason (or at least the romantic artist, the Crusonian pure reasoner); on the other there is outwardness, community, public life, impersonality, the commons, conversation, and the dialogic imagination.
Elizabeth Anderson, “The Epistemology of Democracy”
Michael Brady and Miranda Fricker, The Epistemic Life of Groups
Helen Longino, Science as Social Knowledge