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? There is a further objection made by certain critics, who say Well then, if an orator has to speak on every subject, he must be the master of all the arts. I might answer this criticism in the words of Cicero, de Or. I. vi. 20. in whom I find the following passage:— In my opinion no one can be an absolutely perfect orator unless he has acquired a knowledge of all important subjects and arts. I however regard it as sufficient that an orator should not be actually ignorant of the subject on which he has to speak.

For he cannot have a knowledge of all causes, and yet he should be able to speak on all. On what then will he speak? On those which he has studied. Similarly as regards the arts, he will study those concerning which he has to speak, as occasion may demand, and will speak on those which he has studied.

What then?—I am asked—will not a builder speak better on the subject of building and a musician on music? Certainly, if the orator does not know what is the question at issue. Even an illiterate peasant who is a party to a suit will speak better on behalf of his case than an orator who does not know what the subject in dispute may be. But on the other hand if the orator receive instruction from the builder or the musician, he will put forward what he has thus learned better than either, just as he will plead a case better than his client, once he has been instructed in it.

The builder and the musician will, however, speak on the subject of their respective arts, if there should be any technical point which requires to be established. Neither will be an orator, but he will perform his task like an orator, just as when an untrained person binds up a wound, he will not be a physician, but he will be acting as one.

Is it suggested that such topics never crop up in panegyric, deliberative or forensic oratory? When the question of the construction of a port at Ostia came up for discussion, had not the orator to state his views? And yet it was a subject requiring the technical knowledge of the architect.

Does not the orator discuss the question whether livid spots and swellings on the body are symptomatic of ill-health or poison? And yet that is a question for the qualified physician. Will he not deal with measurements and figures? And yet we must admit that they form part of mathematics. For my part I hold that practically all subjects are under certain circumstances liable to come up for treatment by the orator. If the circumstances do not occur, the subjects will not concern him.

We were therefore right in asserting that the material of rhetoric is composed of everything that comes before the orator for treatment, an assertion which is confirmed by the practice of everyday speech. For when we have been given a subject on which to speak, we often preface our remarks by calling attention to the fact that the matter has been laid before us.

Gorgias indeed felt so strongly that it was the orator's duty to speak on every subject, that he used to allow those who attended his lectures to ask him questions on any subject they pleased. Hermagoras also asserted that the material of oratory lay in the cause and the questions it involved, thereby including every subject that can be brought before it.