Cropsey, Joseph, "Theaetetus," Plato's World: Man's Place in the Cosmos, Chicago, IL: University of Chicago Press, 1995.

Excerpt:

The dialogue Theaetetus reports a conversation between Socrates and Theaetetus that occurred when the latter was perhaps fifteen years old. The conversation took place in the weeks or months preceding the death of Socrates, as the end of the dialogue makes explicit. It suits Plato’s purpose to present the conversation through the reading aloud of a certain reconstruction of it, a reading that takes place decades after the original event.

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