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 just as he will not speak in the same way when he is defending a client on a capital charge and when he is speaking in a lawsuit concerned with an inheritance, or discussing interdicts and suits taking the form of a wager, [*](cp. I. x. 5 and IV. ii. 61. Sponsio (= wager) was a form of lawsuit in which the litigant promised to pay a certain sum of money if he lost his case. The intrdiet was an order issued by the praetor commanding or prohibiting certain action. ) or claims in connexion with
He will not maintain the same tone throughout his exordium, statement of fact, arguments, digression and peroration. He will speak gravely, severely, sharply, with vehemence, energy, fullness, bitterness, or geniality, quietly, simply, Hatteringly, gently, sweetly, briefy or wittily; he will not always be like himself, but he will never be unworthy of himself.