Hilary Kornblith

A number of philosophers, from Thomas Reid1 through C. A. J. Coady2, have argued that one is justified in relying on the testimony of others, and furthermore, that this should be taken as a basic epistemic presumption. If such a general presumption were not ultimately dependent on evidence for the reliability of other people, the ground for this presumption would be a priori. Such a presumption would then have a status like that which Roderick Chisholm claims for the epistemic principle that we are justified in believing what our senses tell us.

Epistemology has changed dramatically since Descartes, but many of the questions epistemologists address today are no different from the questions Descartes addressed. I begin by raising four sets of questions with which Descartes concerned himself, and explain briefly why Descartes regarded these sets of questions as interchangeable. My main purpose, however, is not historical. Rather, I wish to present an outline of a naturalistic approach to these questions. I will not defend naturalistic epistemology. Instead, I hope to explore what a naturalistic approach to some traditional epistemological questions might look like; it is only through a better understanding of the consequences of naturalizing epistemology that we may hope properly to evaluate it. I will argue that questions which Descartes treated as interchangeable will have to be separated by naturalistically minded epistemologists. In the course of evaluating these questions from a naturalistic point of view, I hope to shed some light on the relation between reliability and justification, the dispute between internalist and externalist theories of justification, and the relation between ethics and epistemology.