In as many ways as we can change things which are equivalent to one another, in just so many ways we can change the forms of arguments (ἐπιχειρήματα) and enthymemes (ἐνθυμήματα) in argumentation. This is an instance: if you have borrowed and not repaid, you owe me the money: you have not borrowed and you have not repaid; then you do not owe me the money. To do this skillfully is suitable to no man more than to the philosopher; for if the enthymeme is an imperfect syllogism, it is plain that he who has been exercised in the perfect syllogism must be equally expert in the imperfect also.

Why then do we not exercise ourselves and one another in this manner? Because, I reply, at present, though we are not exercised in these things and not distracted from the study of morality, by me at least, still we make no progress in virtue. What then must we expect if we should add this occupation? and particularly as this would not only be an occupation which would withdraw us from more necessary things, but would also be a cause of self-conceit and arrogance, and no small cause. For great is the power of arguing and the faculty of persuasion, and particularly if it should be much exercised and also receive additional ornament from language: and so universally, every faculty acquired by the uninstructed and weak brings with it the danger of these persons being elated and inflated by it. For by what means could one persuade a young man who excels in these matters that he ought not to become an appendage to them, but to make them an appendage to himself? Does he not trample on all such reasons, and strut before us elated and inflated, not enduring that any man should reprove him and remind him of what he has neglected and to what he has turned aside?

“What then, was not Plato a philosopher?” I reply: and was not Hippocrates a physician? but you see how Hippocrates speaks. Does Hippocrates then speak thus in respect of being a physician? Why do you mingle things which have been accidentally united in the same men? And if Plato was handsome and strong, ought I also to set to work and endeavor to become handsome or strong, as if this was necessary for philosophy, because a certain philosopher was at the same time handsome and a philosopher? Will you not choose to see and to distinguish in respect to what men become philosophers, and what things belong to them in other respects? And if I were a philosopher, ought you also to be made lame? What then? Do I take away these faculties which you possess? By no means; for neither do I take away the faculty of seeing. But if you ask me what is the good of man, I cannot mention to you anything else than that it is a certain disposition of the will with respect to appearances.