How does Socrates get Gorgias to admit that rhetoric is “designed to produce conviction, but not to educate people, about matters of right and wrong”?

How does Socrates get Gorgias to admit that rhetoric is “designed to produce conviction, but not to educate people, about matters of right and wrong”? How does he rely on the distinction between (merely) convincing a person of something, and actually teaching (educating) that person, in his argument? Illustrate the distinction by means of an example of your own. (Pp. 7-17)