XX.  Necessity also engenders belief, which sways both bodies and minds.  For what men say when worn out with tortures, and stripes, and fire, appears to be uttered by truth itself.  And those statements which proceed from agitation of mind, such as pain, cupidity, passion, and fear, because those feelings have the force of necessity, bring authority and belief.  And of this kind are those circumstances from which at times the truth is discovered; childhood, sleep, ignorance, drunkenness, insanity.  For children have often indicated something, though ignorant to what it related; and many things have often been discovered by sleep, and wine, and insanity.  Many men also have without knowing it fallen into great difficulties, as lately happened to Stalenus; who said things in the hearing of certain excellent men, though a wall was between them, which, when they were revealed and brought before a judicial tribunal, were thought so wicked that he was rightly convicted of a capital offence.  And we have heard something similar concerning Pausanias the Lacedaemonian.

But the concourse of fortuitous events is often of this kind; when anything has happened by chance to interrupt, when anything was being done or said which it was desirable should not have been done or said.  Of this kind is that multitude of suspicions of treason which were heaped upon Palamedes.  And circumstances of this kind are sometimes scarcely able to be refuted by truth itself.  Of this kind too is ordinary report among the common people; which is as it were the testimony of the multitude.

But those things which create belief on account of the virtue of the witness are of a two-fold kind; one of which is valid on account of nature, the other by industry.  For the virtue of the gods is eminent by nature; but that of men, because of their industry.

Testimonies of this kind are nearly divine, first of all, that of oration, (for oracles were so called from that very same word, as there is in them the oration of the gods;) then that of things in which there are, as it were, many divine works; first of all, the word itself, and its whole order and ornaments; then the airy flights and songs of birds; then the sound and heat of that same air; and the numerous prodigies of divers kinds seen on the earth; and also, the power of foreseeing the future by means of the entrails of victims:  many things, too, which are shown to the living by those who are asleep:  from all which topics the testimonies of the gods are at times adduced so as to create belief.

In the case of a man, the opinion of his virtue is of the greatest weight.  For opinion goes to this extent, that those men have virtue, not only who do really possess it, but those also who appear to possess it.  Therefore, those men whom they see endowed with genius and diligence and learning, and whose life they see is consistent and approved of, like Cato and Laelius, and Scipio, and many others, they consider such men as they themselves would wish to be.  And not only do they think them such who enjoy honours conferred on them by the people, and who busy themselves with affairs of state, but also those who are orators, and philosophers, and poets, and historians; from whose sayings and writings authority is often sought for to establish belief.