Institutio Oratoria

For what skill does it require to say,

The property is mine, for I am the only son of the deceased,

or

I am the sole heir, since possession of the testator's estate is given by the law of property in accordance with the terms of his will: the property therefore belongs to me

?

But when the reason given is itself disputable, we must establish the certainty of the premises by which we are proposing to prove what is uncertain. For example, if our opponent says

You are not his son

or

You are illegitimate

or

You are not his only son

; or, again,

You are not his heir

or

The will is invalid

or

You are not entitled to inherit

or

You have co-heirs,

we must prove the validity of the reason on which we base our claim that the property should be adjudicated to us.

But when a reason of unusual length intervenes, it is necessary to state the final conclusion, otherwise the major premise and the reason would suffice.

Laws are silent in the midst of arms, and do not require us to await their sanction when the circumstances are such that he who would await their sanction is certain to be the victim of an unjust penalty before ever the just penalty can be claimed.

[*](pro Mil. iv. 10. ) Hence it has been asserted that the form of enthymeme which is based on denial of consequents resembles a reason. But sometimes, again, it is sufficient to state a single proposition as in the example just quoted,

The laws are silent in the midst of arms.

We may also begin with the reason and then proceed to the conclusion as in another passage from the same speech [*](ib. iii. 9. ) :

But if the Twelve Tables permitted the killing of a thief by night under any circumstances, and by day if he used a weapon to defend himself, who is there who will contend that the slayer must be punished under whatever circumstances a man has been killed?

'The process is still further varied by Cicero, and the reason placed third, as in the phrase,

When he sees that the sword is sometimes placed in our hands by the laws themselves.

On the other hand, he places the various parts in the regular order in the following instance:

How can it be unjust to kill a robber who lies in wait for his victim?

[*](ib. iv. 10. ) Next comes the reason:

What is the object of our escorts and our swords?

Last comes the conclusion resulting from the major premise and the reason:

Which we certainly should not be permitted to have, if we were absolutely forbidden to use them.

This form of proof may be countered in three ways, that is to say it may be attacked in all its parts. For either the major premise or the minor or the conclusion or occasionally all three are refuted. The major premise is refuted in the following case:

I was justified in killing him, as he lay in wait for me.

For the very first question in the defence of Milo is

whether it is right that he who confesses that he has killed a man should look upon the light of day.