Institutio Oratoria

For example, a woman who is delivered of a child must have had intercourse with a man, and the reference is to the past. When there is a high wind at sea, there must be waves, and the reference is to the present. When a man has received a wound in the heart, he is bound to die, and the reference is to the future. Nor again can there be a harvest where no seed has been sown, nor can a man be at Rome when he is at Athens, nor have been wounded by a sword when he has no scar. Some have the same force when reversed:

a man who breathes is alive, and a man who is alive breathes. Some again cannot be reversed: because he who walks moves it does not follow that he who moves walks.

So too a woman, who has not been delivered of a child, may have had intercourse with a man, there may be waves without a high wind, and a man may die without having received a wound in the heart. Similarly seed may be sown without a harvest resulting, a man, who was never at Athens, may

There are other indications or εἰκότα, that is probabilities, as the Greeks call them, which do not involve a necessary conclusion. These may not be sufficient in themselves to remove doubt, but may yet be of the greatest value when taken in conjunction with other indications.

The Latin equivalent of the Greek σημεῖον is signum, a sign, though some have called it indicium, an indication, or vestigium, a trace. Such signs or indications enable us to infer that something else has happened; blood for instance may lead us to infer that a murder has taken place. But bloodstains on a garment may be the result of the slaying of a victim at a sacrifice or of bleeding at the nose. Everyone who has a bloodstain on his clothes is not necessarily a murderer.

But although such an indication may not amount to proof in itself, yet it may be produced as evidence in conjunction with other indications, such for instance as the fact that the man with the bloodstain was the enemy of the murdered man, had threatened him previously or was in the same place with him. Add the indication in question to these, and what was previously only a suspicion may become a certainty.

On the other hand there are indications which may be made to serve either party, such as livid spots, swellings which may be regarded as symptoms either of poisoning or of bad health, or a wound in the breast which may be treated as a proof of murder or of suicide. The force of such indications depends on the amount of extraneous support which they receive.

Hermagoras would include among such indications as do not involve a necessary conclusion, an

Atalanta cannot be a virgin, as she has been roaming the woods in the company of young men.

Nor do the Areopagites, when they condemned a boy for plucking out the eyes of quails, seem to have had anything else in their mind than the consideration that such conduct was an indication of a perverted character which might prove hurtful to many, if he had been allowed to grow up. So, too, the popularity of Spurius Maelius and Marcus Manlius was regarded as an indication that they were aiming at supreme power.

However, I fear that this line of reasoning will carry us too far. For if it is an indication of adultery that a woman bathes with men, the fact that she revels with young men or even an intimate friendship will also be indications of the same offence. Again depilation, a voluptuous gait, or womanish attire may be regarded as indications of effeminacy and unmanliness by anyone who thinks that such symptoms are the result of an immoral character, just as blood is the result of a wound: for anything, that springs from the matter under investigation and comes to our notice, may properly be called an indication.

Similarly it is also usual to give the names of signs to frequently observed phenomena, such as prognostics of the weather which we may illustrate by the Vergilian

1. For wind turns Phoebe's face to ruddy gold

Verg. G. i. 431.

1. The crow
2. With full voice, good-for-naught, invites the rain.

ib. i. 388.

For if tile moon turns red owing to the wind, her hue is certainly a sign of wind. And if, as the same poet infers, [*]( Verg. G. i. 422. ) the condensation and rarification of the atmosphere causes that

concert of bird-voices

I now turn to arguments, the name under which we comprise the ἐνθυμήματα, ἐπιχειρήματα, and ἀποδείξεις of the Greeks, terms which, in spite of their difference, have much the same meaning. For the enthymeme (which we translate by commentun or commentatio, there being no alternative, though we should be wiser to use the Greek name) has three meanings: firstly it means anything conceived in the mind (this is not however the sense of which I am now speaking);

secondly it signifies a proposition with a reason, and thirdly a conclusion of an argument drawn either from denial of consequents or from incompatibles [*](v. viii. 5; xiv. 2. n.) ; although there is some controversy on this point. For there are some who style a conclusion from consequents an epicheireme, while it will be found that the majority hold the view that an epicheireme is a conclusion from incompatibles: [*](See v. xiv. 2, VIII. v. 9.) wherefore Cornificius styles it a contrarium or argument from contraries. Some again call it a rhetorical

syllogism, others an incomplete syllogism, because its parts are not so clearly defined or of the same number as those of the regular syllogism, since such

that is an attempt. It would however, in my opinion, be truer to say that it is not our handling of the subject, but the thing itself which we attempt which should be called an ἐπιχείρημα, that is to say the argument by which we try to prove something and which, even if it has not yet been stated in so many words, has been clearly conceived by the mind.

Others regard it not as an attempted or imperfect proof, but a complete proof, falling under the most special [*]( The last or lowest species. p. § 56 and VII. i. 23. ) species of proof; consequently, according to its proper and most generally received appellation it must be understood in the sense of a definite conception of some thought consisting of at least three parts. [*](i.e. the major and minor premisses and the conclusion. See v. xiv. 6 sqq. ) Some call an ἐπιχείρημα a reason,

but Cicero [*](de Inv. . xxxi. 34. ) is more correct in calling it a reasoning, although he too seems to derive this name from the syllogism rather than anything else; for he calls the syllogistic basis [*](See III. vi. 43, 46, 51.) a ratiocinative basis and quotes philosophers to support him. And since there is a certain kinship between a syllogism and an epicheireme, it may be thought that he was justified in his use of the latter term.

An ἀπόδεξις is a clear proof; hence the use of the term γραμμικαὶ ἀποδείξεις,

linear demonstrations

But all authorities, however much they may differ on other points, define both in the same way, in so far as they call both a method of proving what is not certain by means of what is certain. Indeed this is the nature of all arguments, for what is certain cannot be proved by what is uncertain. To all these forms of argument the Greeks give the name of πίστεις , a term which, though the literal translation is fides

a warrant of credibility,

proof.