Book 5
10.69
Or we may give our opponent the choice between two alternatives of which one must necessarily be true, and as a result, whichever he chooses, lie will damage his case. Cicero does this in the pro Oppio: Oppius was accused of embezzling public money and plotting against the life of M. Aurelius Cotta, governor of Bithynia, where Oppius was serving as quaestor. Cicero's defence of him is lost. Was the weapon snatched from his hands when he had attacked Cotta, or when he was trying to commit suicide? and in the pro Vareno: See iv. ii. 26. You have a choice between two alternatives: either you must show that the choice of this route by Varenus was due to chance or that it was the result of this man's persuasion and inducement. He then shows that either admission tells against his opponent. Sometimes again,
10.70
two propositions are stated of such a character that the admission of either involves the same conclusion, as in the sentence, We must philosophise, even though we ought not, or as in the common dilemma, What is the use of a figure, See vii. iv. 28, ix. i. 14, ix. ii. 65. if its meaning is clear? And what is its use, if it is unintelligible? or, He who is capable of enduring pain will lie if tortured, and so will he who cannot endure pain.
