"On Plato's Timaeus and Timaeus' Science Fiction," Interpretation 2, No. 1 (Summer 1971): 21-63. Reprinted in The Archaeology of the Soul, 2012.
“Socrates counts out loud. He makes himself out to be somewhat ridiculous. He does not say, “There are three of you; there should be four.” Nor does he say, “We are all here except so-and-so. Where is he, Timaeus?” Socrates discovers the missing fourth by counting, as though he knew that there should be four but he did not know which of them was missing. He speaks as if his only acquaintance with Timaeus, Hemocrates, and Critias were with anonymous ones. “Fourth” is an ordinal number, a number that completes and makes whole a series. Each of the others is indifferently any other whereas the absent fourth is because of his absence different. He is the completor only because he is absent. Althought he belongs to yesterday’s guests and today’s hosts, he belongs along with Socrates to “us.” He, therefore, in decreasing the number of today’s hosts, makes Socrates the fourth party-member. Socrates does not count himself because he is not counting the members of the party. He is a one unlike the others, but in light of which the other are related to one another. He counts without being counted. Political philosophy, it seems, is a part of philosophy while still being apart from cosmology.”