SOCRATES: I conceive Pericles to have been the most accomplished of rhetoricians.
PHAEDRUS: What of that?
SOCRATES: All the great arts require discussion and high speculation about the truths of nature; hence come loftiness of thought and completeness of execution. And this, as I conceive, was the quality which, in addition to his natural gifts, Pericles acquired from his intercourse with Anaxagoras whom he happened to know. He was thus imbued with the higher philosophy, and attained the knowledge of Mind and the negative of Mind, which were favourite themes of Anaxagoras, and applied what suited his purpose to the art of speaking.
PHAEDRUS: Explain.
SOCRATES: Rhetoric is like medicine.
PHAEDRUS: How so?
SOCRATES: Why, because medicine has to define the nature of the body and rhetoric of the soul—if we would proceed, not empirically but scientifically, in the one case to impart health and strength by giving medicine and food, in the other to implant the conviction or virtue which you desire, by the right application of words and training.
PHAEDRUS: There, Socrates, I suspect that you are right.
SOCRATES: And do you think that you can know the nature of the soul intelligently without knowing the nature of the whole?
PHAEDRUS: Hippocrates the Asclepiad says that the nature even of the body can only be understood as a whole. (Compare Charmides.)