Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
Thus the works of the orator will be great not extravagant, sublime not bombastic, bold not rash, severe but not gloomy, grave but not slow, rich but not luxuriant, pleasing but not effeminate, grand but not grandiose. It is the same with other qualities: the mean is safest, for the worst of all faults is to fly to extremes.
After employing these gifts of eloquence in the courts, in councils, in public assemblies and the debates of the senate, and, in a word, in the performance of all the duties of a good citizen, the orator will bring his activities to a close in a manner worthy of a blameless life spent in the pursuit of the noblest of professions. And he will do this, not because he can ever have enough of doing good,