Institutio Oratoria

The art of war will provide a parallel: it is no doubt based on certain general principles, but it will none the less be far more useful to know the methods employed, whether wisely or the reverse, by individual generals under varying circumstances and conditions of time and place. For there are no subjects in which, as a rule, practice is not more valuable than precept.

Is a teacher to declaim to provide a model for his audience, and will not more profit be derived from the reading of Cicero or Demosthenes? Is a pupil to be publicly corrected if he makes a mistake in declaiming, and will it not be more useful, and more agreeable too, to correct some actual speech? For everyone has a preference for hearing the faults of others censured rather than his own. I might say more on the subject.