Did Plato abandon, or sharply modify, the Theory of Forms in later life? In the Phaedo, Symposium, and Republicit is generally agreed that Plato held that universals exist. But in Parmenides, he subjected that theory to criticism. If the criticism were valid, and Plato knew so, then the Parmenidesmarks a turning point in his thought. If, however, Plato became aware that there are radical differences in the logical behaviour of concepts, and the later dialogues are a record of his attempt to analyse those differences, then Plato’s thought can be said to have moved in a new and vitally important direction after the Parmenides. Studies in Plato’s Metaphysicsbrings together twenty essays by leading philosophers from the UK and the USA reflecting upon this important issue and upon the questions arising from it.

Studies of Plato’s metaphysics have tended to emphasise either the radical change between the early Theory of Forms and the late doctrines of the Timaeus and the Sophist, or to insist on a unity of approach that is unchanged throughout Plato’s career. The author lays out an alternative approach. Focussing on two metaphysical doctrines of central importance to Plato’s thought – the Theory of Forms and the doctrine of Being and Becoming – he suggests a continuous progress can be traced through Plato’s works. He presents his argument through an examination of the metaphysical sections of six of the dialogues: the Euthyphro, Phaedo, Republic, Parmenides, Timaeus, and Sophist.

i. Introductory remarks 1 Plato, but not Socrates, concluded that the Forms are substances. Whether the Forms are substances is not an issue that Socrates had in mind. He did not deny it, but neither did he affirm it. If Socrates were asked a series of questions designed to determine whether he believed that the Forms are substances, he would admit that he had no opinion about this philosophical issue. Unlike Plato, Socrates was not a metaphysician. The same, of course, would not have always been true of Plato. Unlike Socrates, he was a metaphysician. At some point in his career, and at least by the time of the Phaedo and the Republic, Plato did what Socrates never thought to do. Plato considered the question and concluded that the Forms are substances. Although this development occurred more than two thousand years ago, time has not eclipsed its importance. It is one of the most seminal events in the history of the philosophy. With his defense of Socrates's method of intellectual inquiry, and the development of his Theory of Forms, Plato caused a now familiar cluster of metaphysical and epistemological issues to become central to philosophy.

Parens argues that Alfarabi, the tenth-century Muslim philosopher, demonstrated that Plato is not the originator of Western metaphysics, and that what appears to be Plato's metaphysics was intended as a rhetorical defense of his politics.

An important new monograph on Plato's metaphysics, focusing on the theory of the forms, which is the central philosophical concept in Plato's theory.

This book consists of Gregory Vlastos' studies on a variety of themes in Plato's metaphysics, epistemology, ethics, and social philosophy. Although many of the essays have appeared in various philosophical and classical journals or symposia, new in the volume are two major studies. One is on Plato's theory of love, exploring its metaphysical dimension and its far-reaching implications for personal and political relations. The other centers on semantic and logical problems in the Sophist; it offers solutions to crucial difficulties in this fundamental Platonic work. In these essays the author presents ideas which are likely to provoke comment and may be discussed as vigorously in scholarly journals as has some of his earlier work. The other papers, some of them extensively revised, comprise virtually all the author's published work on Plato, with the exception of a few papers easily accessible elsewhere. This second edition includes three additional essays and extensive notes that were not included in the original edition.