Social epistemology is a burgeoning branch of contemporary epistemology. Since the 1970s, philosophers have taken an ever-increasing interest in such topics as the epistemic value of testimony, the nature and function of expertise, the proper distribution of cognitive labor and resources among individuals in communities, and the status of group reasoning and knowledge. This trend emerged against the resistance of the widely shared view that social considerations are largely irrelevant to epistemological concerns. The trend was stimulated by diverse approaches to the study of knowledge, in such fields as library science, educational theory, the sociology of science, and economics, and within philosophy itself, in the decades preceding the 1980s. To name only a few influences within philosophy, W. V. Quine promoted a naturalistic approach to knowledge, and many who accepted the relevance of nature to epistemology found it sensible to accept the relevance of social factors as well. Thomas S. Kuhn suggested that social factors precipitate revolutionary conceptual and doctrinal changes in the history of science. And feminist epistemologists uncovered the importance of gender differences in knowledge – a species of social factor.

In this paper I discuss Plato's conception of expertise as a part of the Platonic theory of a good, successful life (eudaimonia). In various Platonic dialogues, Socrates argues that the good life requires a certain kind of knowledge that guides all our good, beneficial actions: the “knowledge of the good and bad”, which is to be acquired by “questioning ourselves and examining our and others’ beliefs”. This knowledge encompasses the particular knowledge of how to recognize experts in a given technical domain. The central element in Socrates’ account of an expert is what I call the truth-and-caring criterion: an expert has to make seeking the truth and avoiding (avoidable) error her supreme epistemic goal and she has to make caring for common goods the supreme goal of practising her expertise.

Medieval epistemology begins as ideal theory: when is one ideally situated with regard to one's grasp of the way things are? Taking as their starting point Aristotle's Posterior Analytics, scholastic authors conceive of the goal of cognitive inquiry as the achievement of scientia, a systematic body of beliefs, grasped as certain, and grounded in demonstrative reasons that show the reason why things are so. Obviously, however, there is not much we know in this way. The very strictness of this ideal in fact gives rise to a body of literature on how Aristotle's framework might be relaxed in various ways, for certain specific purposes. In asking such questions, scholastic authors are in effect pursuing the project of social epistemology, by trying to adapt their ideal theory to the circumstances of everyday life.

The standard interpretation of Hume on testimony takes him to be a reductionist; justification of beliefs from testimony ultimately depends on one's own first-person experience. Yet Hume's main discussions of testimony in the Treatise and first Enquiry suggest a social account. Hume appeals to shared experience and develops norms of belief from testimony that are not reductionist. It is argued that the reductionist interpretation rests on an overly narrow view of Hume's theory of ideas. By attending to such mechanisms of the imagination as abstraction and fictions, it is shown that Hume's theory of ideas does not forestall a non-reductionist social epistemology.

It has been argued that Hume's account of testimony is seriously inadequate: an autonomous knower of the sort Hume defends cannot, through simple inductive methods, justify accepting another's testimony as true. This conclusion is no doubt correct. But Hume does not defend the idea of an autonomous knower, nor does he defend relying upon simple inductive methods. An examination of Hume's critique of Descartes’ method of doubt shows him as a defender of what might be called the responsible knower, and reveals the sophistication of the inductive methods he wishes to defend. It is shown that Hume can and does use these methods to justify accepting the testimony of others.

The present paper argues for the relevance of Immanuel Kant and the German Enlightenment to contemporary social epistemology. Rather than distancing themselves from the alleged ‘individualism’ of Enlightenment philosophers, social epistemologists would be well-advised to look at the substantive discussion of social-epistemological questions in the works of Kant and other Enlightenment figures. After a brief rebuttal of the received view of the Enlightenment as an intrinsically individualist enterprise, this paper charts the historical trajectory of philosophical discussions of testimony as a source of knowledge, via such philosophers as C. Thomasius, C. A. Crusius, J. M. Chladenius, G. F. Meier, and finally Kant. Building on recent work on Kant's epistemology of testimony, the paper considers Kant's broader contributions to social epistemology. This includes an analysis of Kant's comments on the social basis of contingent epistemic standards, e.g. in the sciences, as well as on problems arising from the management of what Kant calls the growing ‘volume of knowledge’. Special attention is paid to the relation between Kant's views and contemporary problems arising both in the context of education and from our increased reliance on scientific experts.