Rhetoric, Socrates continues, is the art of influencing the soul, and therefore an orator must know the particular traits of the particular soul he is trying to influence. Just as different medicines work with different bodies, so different techniques of persuasion will work on different types of souls.

If we want to discuss anything clearly, Socrates continues, we must ask whether or not the topic or thing is part of a whole (“complex”) or singular (“simple”). If it belongs to a larger group (for example, a single soul among many, or a single body among many), one must determine the “essential nature” of the object. Socrates asserts that this is the only true way to discuss anything “scientifically”; any other method falls short of this goal and is of no value. Socrates reminds Phaedrus that they still haven’t discussed the relationship of written to spoken speeches, and he proposes to tell one more myth to help him begin this final topic.

Socrates states that Thoth, an Egyptian god, came before the Egyptian king to present his inventions. One of these was writing, which Thoth described as a way for humans to increase both their wisdom and their memory.