Every artificial proof consists either of indications, arguments or examples. I am well aware that many consider indications to form part of the arguments. My reasons for distinguishing them are twofold. In the first place indications as a rule come under the head of inartificial proofs: for a bloodstained garment, a shriek, a dark blotch and the like are all evidence analogous to documentary or oral evidence and rumours; they are not discovered by the orator, but are given him with the case itself.

My second reason was that indications, if indubitable, are not arguments, since they leave no room for question, while arguments are only possible in controversial matters. If on the other hand they are doubtful, they are not arguments, but require arguments to support them.

The two first species into which artificial proofs may be divided are, as I have already said, those which involve a conclusion and those which do not. The former are those which cannot be otherwise and are called τεκμήρια, by the Greeks, because they are indications from which there is no getting away. These however seem to me scarcely to come under the rules of art. For where an indication is irrefutable, there can be no dispute as to facts.

This happens whenever there can be no doubt that something is being or has been done, or when it is impossible for it to be or have been done. In such cases there can be no dispute as to the fact. This kind of proof may be considered in connexion with past, present or future time.

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 never have been at Rome, and a man who has a scar may not have received a sword-wound.

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 argument such as the following, Atalanta cannot be a virgin, as she has been roaming the woods in the company of young men. If we accept this view, I fear that we shall come to treat all inferences from a fact as indications. None the less such arguments are in practice treated exactly as if they were indications.

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 For wind turns Phoebe's face to ruddy goldVerg. G. i. 431. and The crowWith full voice, good-for-naught, invites the rain.ib. i. 388. If these phenomena are caused by the state of the atmosphere, such an appellation is correct enough.

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 of which he speaks, we may agree in regarding it as a sign. We may further note that great things are sometimes indicated by trivial signs, witness the Vergilian crow; that trivial events should be indicated by signs of greater importance is of course no matter for wonder.