Plato and the Copula: Sophist 251–59

Abstract

My purpose is not to give a full interpretation of this difficult and important passage, but to discuss one particular problem, taking up some remarks made by F. M. Cornford (in Plato’s Theory of Knowledge) and by Mr. R. Robinson (in his paper on Plato’s Parmenides, Classical Philology, 1942).¹ First it may be useful to give a very brief and unargued outline of the passage. Plato seeks to prove that concepts² are related in certain definite ways, that there is a συμπλοκὴ ϵἰδ̑ων (an interweaving of Forms) (251D–252E). Next (253) he assigns to philosophy the task of discovering what these relations are: the philosopher must try to get a clear view of the whole range of concepts and of how they are interconnected, whether in genus-species pyramids or in other ways. Plato now gives a sample of such philosophising. Choosing some concepts highly relevant to problems already broached in the Sophist he first (254–55) establishes that they are all different one from the other, and then (255E–258) elicits the relationships in which they stand to one another. The attempt to discover and state these relationships throws light on the puzzling notions ὄν (being) and μὴ ὄν (not being) and enables Plato to set aside with contempt certain puzzles and paradoxes propounded by superficial thinkers (259).