Institutio Oratoria

And things which form the material for other artists, do not for that reason cease forthwith to be material for rhetoric. For if I ask what is the material of the sculptor, I shall be told bronze; and if I ask what is the material of the maker of vessels (I refer to the craft styled χαλκευτική by the Greeks), the answer will again be bronze: and yet there is all the difference in the world between vessels and statues.

Similarly medicine will not cease to be an art, because, like the art of the gymnast, it prescribes rubbing with oil and exercise, or because it deals with diet like the art of cookery.

Again, the objection that to discourse of what is good, expedient or just is the duty of philosophy presents no difficulty. For when such critics speak of a philosopher, they mean a good man. Why then should I feel surprised to find that the orator whom I identify with the good man deals with the same material?

There is all the less reason, since I have already shown in the first book [*]( Pref. § 10 sqq. ) that philosophers only usurped this department of knowledge after it had been abandoned by the orators: it was always the peculiar property of rhetoric and the philosophers are really trespassers. Finally, since the discussion of whatever is brought before it is the task of dialectic, which is really a concise form of oratory, why should not this task be regarded as also being the appropriate material for continuous oratory?

Well then, if an orator has to speak on every subject, he must be the master of all the arts.

In my opinion no one can be an absolutely perfect orator unless he has acquired a knowledge of all important subjects and arts.