Plato and rhetoric are connected because Plato, a Greek philosopher, was one of the first people to discuss rhetoric in detail. Not presented in a single book, as with Aristotle's Rhetoric, Plato makes remarks on rhetoric and alludes to it in four books: Gorgias, Ion, Phaedrus, and The Republic. He saw rhetoric as being the opposite of philosophy and therefore, many of his thoughts are critiques of rhetoric. In short, he believed rhetoric was the art of persuasion and philosophy the pursuit of truth.
Some details need to be kept in mind when discussing Plato and rhetoric. First, Plato and Socrates must be considered equally because their discussions reflect the philosophies of both men. Second, Plato believed that poetry and rhetoric were equal and of the same ilk; therefore, the two must be considered interchangeable. This means that many of his discussions concerning poetry can also be ascribed to his feelings towards rhetoric.
In Gorgias, the rhetorician Gorgias is asked to define rhetoric, but is unable to do so to Plato's satisfaction. Socrates then describes rhetoric as a speech that either promotes or condemns a person or idea, whereas philosophy looks for answers. Another difference between a philosopher like Plato and rhetoric, as espoused by Gorgias, is that the philosopher is open to being proved wrong. The rhetorician, on the other hand, uses words as tools in order to gain power over the people. Plato believed that rhetoric has the power to shape human beliefs.
Ion is a performer of poetry and a self-confessed explainer of the Greek poet, Homer. In Ion, Socrates and Plato test Ion's claims. From this, the two philosophers decide that a good rhetorician should be able to spot a bad one.
Socrates defines a good rhetorician or poet as a person who understands the subject he or she is talking about. He asks Ion if he or Homer understand the art of war in order to judge the philosophical truth of The Iliad. Socrates concludes that a rhetorician should either confess his or her human failings or claim to be purely inspirational and, therefore, divine.
Phaedrus repeats the claim that poetry and rhetoric are acts of inspiration. Plato's dialogue calls rhetoric shameful because it is often built on false knowledge. Sophistry is worse, in Plato's mind, because it is rhetoric built on intentional deception. In order to avoid shame, the rhetorician should understand the subject he or she is talking about. The successful rhetorician, whether shameful or not, gains success by understanding the human soul.
Plato's Republic is a dialogue examining the perfect city. According to Plato, justice comes from the people, but only if the people are properly educated. This education, he believes, must be built on philosophical foundations. Plato and rhetoric come to an explosive head when the latter is described by the former, and by Socrates, as akin to myth creation. Parables, poetry, and false rhetoric are considered forms of miseducation.
The subject of Plato and rhetoric has left many philosophers confused because Plato never satisfactorily explains why poetry and rhetoric are linked. It appears from his writings that poetry and rhetoric are both considered arts of persuasion. They are both designed to stir the human soul and to ferment beliefs and opinions on a person. Socrates admits that such is their power that even the most philosophically minded of people cannot help but be drawn into rhetoric's power.