Timaeus 48e-52d and the Third Man Argument

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Cambridge University Press


In this paper I examine a much discussed passage of the Timaeus. This passage contains one of the most important descriptions of Plato's ontology to be found in all the dialogues. The ontological scheme there described differs from that presented in the middle Platonic dialogues in that a third sort of entity, the Receptacle or space, is added to the two classes of things familiar to readers of the Phaedo and Republic: Being (i.e. the Forms) and Becoming (the phenomenal world). The introduction of the Receptacle into Plato's ontology enables Plato to clarify the relation between the orders of Being and Becoming in a way not otherwise possible. When the relation between the Forms and their phenomenal counterparts has been clarified, I shall argue, it becomes clear that the Theory of Forms as presented in the Timaeus is in fact a coherent metaphysical theory, one which is not susceptible to the Third Man Argument. This fact in turn bears (although somewhat indirectly) on the vexed question of the place of the Timaeus in the chronology of Plato's works.

I shall proceed in the following way. First, I shall attempt to place this passage of the dialogue in its proper context. Second, I shall undertake a detailed explication of the passage itself. Third, I shall indicate what the import of the passage is for Plato's ontology. Fourth, I shall attempt to show how Plato's ontology, thus described, makes the Third Man idle. Fifth, I shall address briefly the chronological issue.