Institutio Oratoria

Quintilian

Quintilian. Institutio Oratoria, Volume 1-4. Butler, Harold Edgeworth, translator. Cambridge, Mass; London: Harvard University Press, William Heinemann Ltd., 1920-1922.

If self-control is a virtue, abstinence is also a virtue.
If a guardian should be required to be faithful to his trust, so should an agent.
To this class belongs the type of argument called ἐπαγωγή by the Greeks, induction by Cicero. [*](de Inv. i. 31. ) Or arguments may be drawn from unlikes:
It does not follow that if joy is a good thing, pleasure also is a good thing
:
It does not follow that what applies to the case of a woman applies also to the case of a ward.
Or from contraries:
Frugality is a good thing, since luxury is an evil thing
:
If war is the cause of ill, peace will prove a remedy
:
If he who does harm unwittingly deserves pardon, he who does good unwittingly does not deserve a reward.

Or from contradictions:

He who is wise is not a fool.
Or from consequences necessary or probable [*]( It is possible that Quintilian regards adiuncta as = consequentia. The distinction made above is that made by Cicero, Top. xii. ) :
If justice is a good thing, we must give
v4-6 p.243
right judgment
:
If breach of faith is a bad thing, we must not deceive.
And such arguments may also be reversed. Similar to these are the following arguments, which must therefore be classed under this same head, since it is to this that they naturally belong:
A man has not lost what he never had
:
A man does not wittingly injure him whom he loves
:
If one man has appointed another as his heir, he regarded, still regards and will continue to regard him with affection.
However, such arguments, being incontrovertible, are of the nature of absolute indications. [*](See ch. ix.)

These, however, I call consequent or ἀκόλουθα goodness, for instance, is consequent on wisdom: while in regard to things which merely have taken place afterwards or will take place I use the term insequent or παρεπόμενα, though I do not regard the question of terminology as important. Give them any name you please, as long as the meaning is clear and it is shown that the one depends on time, the other on the nature of things.

I have therefore no hesitation in calling the following forms of argument also consequential, although they argue from the past to the future: some however divide them into two classes, those concerned with action, as in the pro Oppio,

How could he detain against their will those whom he was unable to take to the province against their will?
and those concerned with time, as in the Verrines, [*](Verr. I. xlii. 109. The praetor on entering office on Jan. I issued an edict announcing the principles on which his rulings would be given. This edict was an interpretation of the law of Rome, and held good only during the praetor's year of office. )
If the first of January puts an end to the authority of the praetor's edict, why should the commencement of its authority not likewise date from the first of January?