ABSTRACT
HARDLY a text in Plato has been discussed as much in the last forty years 2 as the two passages in the Parmenides purporting to prove that the Theory of Forms involves an infinite regress, which came to be dubbed within Plato's lifetime the ‘Third Man’ Argument. A flood of light has been thrown both on the meaning of the text and on its philosophical implications. Yet in spite of this, disagreement continues. Is the Third Man Argument a valid objection to the Theory of Forms? Did Plato believe that it was valid? One can find acute and learned critics on both sides of both of these basic questions. I write as the beneficiary of their controversies, but not in a controversial spirit. If any progress in agreement is to be made at this juncture it must come from some advance in understanding of the logical structure of the Argument. To this end I shall pursue its analysis further than I think anyone has yet found it profitable to push it. This will be the task of Section I. I shall then consider in Section II what this may teach us about the Theory of Forms and also about the state of mind in which Plato held this theory when he turned against it that battery of objections of which the Third Man Argument is the most interesting and the most instructive.
