Abstract

This dissertation makes two major claims. First, I argue that it is a mistake to understand Plato's epistemology in terms of modern epistemological categories. Second, I argue that Plato's epistemology can be properly understood only by attending to his claim that knowledge is a capacity. ;In the Theaetetus Plato explores three different definitions of knowledge. The final proposal, on which I focus, is that knowledge is true opinion with an account. Plato rejects the proposals for defining knowledge and seems to end the dialogue in failure. Many commentators have taken this ending to be misleading. Since the third definition of knowledge resembles the contemporary idea that knowledge is justified true belief, many commentators have tried to show that Plato accepts it, but leaves it to the reader to work out the details. ;I argue that this understanding of the Theaetetus is mistaken, and that Plato rejects this definition of knowledge for good reason. I propose that the dialogue be read negatively; Plato's rejections of the proposed definitions are sincere, and we can best understand his project to be that of eliminating mistaken conceptions of knowledge. ;In the Republic, Plato argues that knowledge and opinion are capacities and are distinguished by what they produce and by what they are related to. On this conception, to know is to have the capacity to produce true judgments concerning what one knows. The notion of a capacity differs from that of a cognitive state. On the state conception, to know is to be in a state that has as its content a certain piece of knowledge: if I know something, I am in a state of knowing that thing. It is because the Theaetetus focuses on the notion of knowledge as a state that constitutes Plato's central reason for rejecting the definition mentioned above