Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
It was, then, nature that created speech, and observation that originated the art of speaking. Just as men discovered the art of medicine by observing that some things were healthy and some the reverse, so they observed that some things were useful and some useless in speaking, and noted them for imitation or avoidance, while they added certain other precepts according as their nature suggested. These observations were confirmed by experience and each man proceeded to teach what he knew.
Cicero, [*](de Inv. i. 2. ) it is true, attributes the origin of oratory to the founders of cities and the makers of laws, who must needs have possessed the gift of eloquence. But why he thinks this the actual origin, I cannot understand, since there still exist certain nomad peoples without cities or laws, and yet members of these peoples perform the duties of ambassadors, accuse and defend, and regard one man as a better speaker than another.
The art of oratory, as taught by most authorities, and those the best, consists of five parts:- invention, arrangement, expression, memory, and delivery or action (the two latter terms being used synonymously). But all speech expressive of purpose involves also a subject and words.
If such expression is brief
It is for this reason that memory forms the fourth department. But a delivery, which is rendered unbecoming cither by voice or gesture, spoils everything and almost entirely destroys the effect of what is said. Delivery therefore must be assigned the fifth place.