Institutio Oratoria
Quintilian
Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.
Arguments such as the following belong in the main to the hortative department of oratory:—
Virtue brings renown, therefore it should be pursued; but the pursuit of pleasure brings ill-repute, therefore it should be shunned.But the warning that we should not necessarily search for the originating cause is just: an example of such error is provided by the speech of Medea [*]( The opening of Ennius' translation of the Medea of Euripides. ) beginning
Ah! would that never there in Pelion's grove,as though her misery or guilt were due to the fact that there
or I might cite the words addressed by Philoctetes to Paris, [*]( From the Philoctetes of Accius, Ribbeck fr. 178. )
- Hadst thou been other than thou art, then I
- Had ne'er been plunged in woe.
But for the fact that Cicero [*](Top. iii. 12. ) has done so, I should regard it as absurd to add to these what is styled the conjugate argument, such as
Those who perform a just act, act justly,a self-evident fact requiring no proof; or again,
Every man has a common right to send his cattle to graze in a common pasture.
Some call these arguments derived from causes or efficients by the Greek name ἐκβάσεις that is, results; for in such cases the only point considered is how one thing results from another. Those arguments which prove the lesser from the greater or the greater from the less or equals from equals are styled apposite or comparative.
A conjecture as to a fact is confirmed by argument from something greater in the following sentence:
If a man commit sacrilege, he will also commit theft; from something less, in a sentence such as
He who lies easily and openly will commit perjury; from something equal in a sentence such as
He who has taken a bribe to give a false verdict will take a bribe to give false witness.
Points of law may be proved in a similar manner; from something greater, as in the sentence
If it is lawful to kill an adulterer, it is lawful to scourge him; from something less,
If it is lawful to kill a man attempting theft by night, how much more lawful is it to kill one who attempts robbery with violence; from something equal,
The penalty which is just in the case of parricide is also just in the case of matricide.In all these cases we follow the syllogistic method. [*](See III. vi. 15, 43, 88.)
The following type of argument on the other hand is more serviceable in questions turning
If strength is good for the body, health is no less good.
If theft is a crime, sacrilege is a greater crime.
If abstinence is a virtue, so is self-control.
If the world is governed by providence, the state also requires a government.
If a house cannot be built without a plan, what of a whole city?
If naval stores require careful supervision, so also do arms.