Abstract

In this work, I offer and seek to defend a theory of epistemic rationality. Epistemic rationality, as I use the term, denotes, roughly, that property of a belief, a sufficient degree of which, absent Gettier problems, is, together with true belief, necessary and sufficient for knowledge. I reject the term "justification" for that concept because justification is an internalist notion, and, I argue, no internalist account of epistemic rationality can be adequate. ;I argue that any adequate theory of epistemic rationality must require of epistemically rational beliefs that they be formed by properly functioning cognitive faculties. Standard versions of internalism, coherentism, and reliabilism run afoul of that requirement and accordingly fail, in predictable ways, as accounts of epistemic rationality. ;In my own theory, which I call, "teleological reliabilism", I claim that a given belief is epistemically rational for a person if, and only if, that belief is produce and sustained in that person by properly functioning cognitive faculties. I employ, as a heuristic device, the hypothetical assumption of an ideal cognitive designer in order to explicate what it is for faculties to function properly. I argue, against Daniel Dennett and Alvin Plantinga, who have similar views to mine on the relationship of design or purpose to rationality, that this counterfactual formulation of the design assumption is essential for an accurate account of proper cognitive function. I argue that teleological reliabilism avoids the major pitfalls of rival versions of reliabilism, including the problem of generality. ;I use the resources of teleological reliabilism to explain what I call the modified Gettier problem, i.e., the fact that epistemically rational true belief is insufficient for knowledge. In the spirit of teleological reliabilism, I propose and defend a theory of knowledge according to which knowledge is true belief that is reliably produced by properly functioning cognitive faculties and argue that it satisfies the conditions necessary and sufficient for avoiding the Gettier problem and modified Gettier problem