BELIEVER. On one hand, I think Plato/Socrates is making an excellent argument here. He’s saying that in order for rhetoric to be rightly called an “art” (something that can lay claim to serious consideration of both the body (the theory) and the soul (the practice)), the rhetoritician must know the truth about her topic (and therefore must of course know how to define and classify it), must know each “class of speech” (167) well enough to choose which is best in the particular situation, and must know her audience well enough to make the best choices thereof. That makes a lot of sense. Without this knowledge, the rhetoritician will not be able to choose the right argument or the right form of persuasion. She might even be lead astray (unknowingly) and argue against what is “right” or “true.”
DOUBTER. On the other hand, while Plato is right, I think, to emphasize that more than mere ability to persuade is required for the good rhetoritician (just as a physician or a musician needs to know more about their art than mere mechanics), I don’t think he is correct that the good rhetorititian needs to be nothing less than a superb philosopher. For that is what Plato/Socrates is saying. He makes it an either/or proposition: either the rhetoritician has mastered all this knowledge and insight or he fails his art. So I doubt Plato/Socrates on two levels. One, what he’s arguing seems too all-or-nothing to be true or workable (though “workable” would not be something he would care to strive for, anyway!). And two, it’s almost as if he is saying, “Look, in order to practice the “art of rhetoric” you have to do/know X, Y, and Z. And since X, Y, and Z are obviously so difficult even most philosophers don’t accomplish them, therefore the “art of rhetoric” is really not possible. I get the feeling that’s what he’s doing in this dialogue: undermining even the possiblity of an “art” of rhetoric. And from what we know he said in the Gorgias, if rhetoric cannot be an “art,” then it will always be a mere “flattery,” something able to be practical (sometimes) but not seriously concerned with the “true.”
I might have thought Plato was sincerely offering criteria for the true “art” of rhetoric 1) if he had not emphasized the all-or-nothingness of his thesis, 2) if he had, in all the mentions of contemporary rhetoriticians, mentioned at least one who had either reached or had come close to his standards, and 3) if he had not included in the dialogue so many references (spoken by both Phaedrus and Socrates) to how supremely difficult this standard was. Socrates even goes so far as to say, “But this ability [of the art of rhetoric] [a man] will not gain without much diligent toil, which a wise man ought not to undergo for the sake of speaking and acting before men, but that he may be able to speak and to do everything, so far as possible, in a manner pleasing to the gods” (165). To know one’s subject in its truest “reality,” to know the souls of one’s audience so well as to choose the perfect method of persuasion and arrangement — this is all clearly an ideal for anyone. And one that he gives no indication anyone he knows, not even himself, has attained. So why should the art of rhetoric be limited to those who have attained it?
I also found it curious that even though Plato/Socrates emphasizes dialectic as the ideal way to attain “true” knowledge, he doesn’t discuss his doctrine of the soul via dialectic, but merely asserts it as “gospel truth.” I suppose we are supposed to assume that since he is such a serious philosopher that he is simply remembering the Knowledge (capital K) he once had before his soul was encumbered in a body.