Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
For a man's character is generally revealed and the secrets of his heart are laid bare by his manner of speaking, and there is good ground for the Greek aphorism that,
as a man lives, so will he speak.The following vices are of a meaner type: grovelling flattery, affected buffoonery, immodesty in dealing with things or words which are unseemly or obscene, and disregard of authority on all and every occasion. They are faults which, as a rule, are found in those who are over-anxious either to please or amuse.
Again, different kinds of eloquence suit different speakers. For example, a full, haughty, bold and florid style would be less becoming to an old man than that restrained, mild and precise style to which Cicero refers, when he says that his style is beginning to grow grey-haired. [*](Brut. ii. 8. ) It is the same with their style as their clothes; purple and scarlet raiment goes ill with grey hairs.
In the young, however, we can endure a rich and even, perhaps, a risky style. On the other hand, a dry, careful and compressed style is unpleasing in the young as suggesting the affectation of severity, since even the authority of character that goes with age is considered as premature in young men. Soldiers are best suited by a simple style.