Timothy Chappell’s new translation of the Theaetetus is presented here in short sections of text, each preceded by a summary of the argument and followed by his philosophical commentary on it. Introductory remarks discuss Plato and his works, his use of dialogue, the structure of the Theaetetus, and alternative interpretations of the work as a whole. A glossary and bibliography are provided.

In the Theaetetus, Plato looks afresh at a problem to which, he now realizes, he had earlier given an inadequate answer: the problem of the nature of knowledge. What Plato has to say on this question is of great interest and importance, not only to scholars of Plato, but also to philosophers with wholly contemporary interests. This book is a sustained philosophical analysis and critique of the Theaetetus. David Bostock provides a detailed examination of Plato's arguments and the issues that (...) they raise. He adjudicates on rival interpretations of the text, and looks at the relations between this and other works of Plato. The book does not presuppose any knowledge of Greek. (shrink)

It is important for our purposes to notice that in this first reduction of Theætetus' definition of knowledge as perception, Plato has introduced the distinction between sense object and physical object, for he has specifically said, "when the same wind is blowing, one of us feels chilly, the other does not." In using this example. Plato has, as Cornford observes, raised the question of how the several sense objects are related to the single physical object. This question is one of (...) the two major questions with which this paper will deal, since it is, as I have remarked, the more important question concerning the ontological status of sense-data. Cornford feels that Protagoras probably held that the physical object is both hot and cold, different observers perceiving different aspects of the same object. That is, Cornford suggests that Protagoras' own answer to this question of the relation between sense-data and physical objects is one of complete identification in every case. We will see that this theory is similar in many ways to the one worked out by Plato in the Theætetus, but the distinction between the physical object and the sense object, between the wind which feels hot and cold to different people, makes certain characteristic differences between Plato's and Protagoras' theory. Before going on to examine these differences, it is necessary to follow the further development of Plato's general theory of perception. (shrink)

The Theaetetus is a principal field of battle for one of the main disputes between Plato's interpreters. This is the dispute between unitarians and revisionists. This article focuses on Plato's ideas on unitarians and revisionists. Plato's greatest work on epistemology, in the Theaetetus, Plato has much to say about the nature of knowledge elsewhere. But only the Theaetetus offers a set-piece discussion of the question “What is knowledge?” This question is raised most vividly for readers of Plato when assessing the (...) central epistemological claim of the Republic: that knowledge is impossible unless one grasps the forms, and also for those who do not recognize the existence of the forms. Plato adopts a complex strategy for examining the nature of knowledge in the Theaetetus: he sometimes has Socrates examine a conception of knowledge purely on its own terms. The two major ideas dealt with in the article are change and form. (shrink)