Institutio Oratoria

I think I hear certain persons (for there will always be some who had rather be eloquent than good) asking,

Why then is there so much art in connexion with eloquence? Why have you talked so much of 'glosses,' [*](color is a technical term for the particular aspect given to a case by skilful manipulation of the facts—the 'gloss' or 'varnish' put on them by the accused or accuser. —Peterson on Quint. X. i. 116. ) the methods of defence to be employed in difficult cases, and sometimes even of actual confession of guilt, unless it is the case that the power and force of speech at times triumphs over truth itself? For a good man will only plead good cases, and those might safely be left to truth to support without the aid of learning.

Now, though my reply to these critics will in the first place be a defence of my own work, it will also explain what

I consider to be the duty of a good man on occasions when circumstances have caused him to undertake the defence of the guilty. For it is by no means useless to consider how at times we should speak in defence of falsehood or even of injustice, if only for this reason, that such an investigation will enable us to detect and defeat them with the greater ease, just as the physician who has a thorough knowledge of all that can injure the health will be all the more skilful in the prescription of remedies.