These are the arguments of Chrysippus, which even he himself did not refute. For what could he do with such a conclusion as this,—“If it shines, it shines: but it does shine, therefore it does shine?” He must give in; for the principle of the connexion compels you to grant the last proposition after you have once granted the first. And in what does this conclusion differ from the other,—“If you lie, you lie; but you do lie, therefore you do lie?” You assert that it is impossible for you either to approve or disapprove of this: if so, how can you any more approve or disapprove of the other? If the art, or the principle, or the method, or the force of the one conclusion avails, they exist in exactly the same degree in both.
This, however, is their last resource. They demand that one should make an exception with regard to these points which are inexplicable. I give my vote for their going to some tribune of the people; for they shall never obtain this exception from me. In truth, when they cannot prevail on Epicurus, who despises and ridicules the whole science of dialectics, to grant this proposition to be true, which we may express thus—“Hermachus will either be alive to-morrow or he will not;” when the dialecticians lay it down that every disjunctive proposition, such as “either yes or no” is not only true but necessary; you may see how cautious he is, whom they think slow. For, says he, if I should grant that [pg 069] one of the two alternatives is necessary, it will then be necessary either that Hermachus should be alive to-morrow, or not. But there is no such necessity in the nature of things. Let the dialecticians then, that is to say, Antiochus and the Stoics, contend with him, for he upsets the whole science of dialectics.
For if a disjunctive proposition made up of contraries, (I call those propositions contraries when one affirms and the other denies,) if, I say, such a disjunctive can be false, then no one is ever true. But what quarrel have they with me who am following their system? When anything of that kind happened, Carneades used to joke in this way:—“If I have drawn my conclusion correctly, I gain the cause: if incorrectly, Diogenes shall pay back a mina;” for he had learnt dialectics of that Stoic, and a mina was the pay of the dialecticians.
I, therefore, follow that system which I learnt from Antiochus; and I find no reason why I should judge “If it does shine, it does shine” to be true, because I have learnt that everything which is connected with itself is true; and yet not judge “If you lie, you lie,” to be connected with itself in the same manner. Either, therefore, I must judge both this and that to be true, or, if I may not judge this to be true, then I cannot judge that to be.
XXXI. However, to pass over all those prickles, and all that tortuous kind of discussion, and to show what we are:—after having explained the whole theory of Carneades, all the quibbles of Antiochus will necessarily fall to pieces. Nor will I say anything in such a way as to lead any one to suspect that anything is invented by me. I will take what I say from Clitomachus, who was with Carneades till his old age, a man of great shrewdness, (indeed, he was a Carthaginian,) and very studious and diligent. And he has written four books on the subject of withholding assent; but what I am going to say is taken out of the first.
Carneades asserts that there are two kinds of appearances; and that the first kind may be divided into those which can be perceived and those which cannot; and the other into those which are probable and those which are not. Therefore, those which are pronounced to be contrary to the senses and contrary to evidentness belong to the former division; [pg 070] but that nothing can be objected to those of the second kind. Wherefore his opinion is, that there is no appearance of such a character that perception will follow it, but many such as to draw after them probability. Indeed, it would be contrary to nature if nothing were probable; and that entire overturning of life, which you were speaking of, Lucullus, would ensue. Therefore there are many things which may be proved by the senses; only one must recollect that there is not in them anything of such a character that there may not also be something which is false, but which in no respect differs from it in appearance; and so, whatever happens which is probable in appearance, if nothing offers itself which is contrary to that probability, the wise man will use it; and in this way the whole course of life will be regulated.
And, in truth, that wise man whom you are bringing on the stage, is often guided by what is probable, not being comprehended, nor perceived, nor assented to, but only likely; and unless a man acts on such circumstances there is an end to the whole system of life. For what must happen? Has the wise man, when he embarks on board ship, a positive comprehension and perception in his mind that he will have a successful voyage? How can he? But suppose he goes from this place to Puteoli, thirty furlongs, in a seaworthy vessel, with a good pilot, and in fine weather like this, it appears probable that he will arrive there safe. According to appearances of this kind, then, he will make up his mind to act or not to act; and he will be more willing to find the snow white than Anaxagoras, who not only denied that fact, but who affirmed, because he knew that water, from which snow was congealed, was of a dark colour, that snow did not even look white. And he will be influenced by anything which affects him in such a way that the appearance is probable, and not interfered with by any obstacle. For such a man is not cut out of stone or hewn out of oak. He has a body, he has a mind, he is influenced by intellect, he is influenced by his senses, so that many things appear to him to be true, and yet not to have conspicuous and peculiar characteristics by which to be perceived. And therefore the wise man does not assent to them, because it is possible that something false may exist of the same kind as this true thing. Nor do we speak against the senses differently from the Stoics, who say that many things [pg 071] are false, and are very different from the appearance which they present to the senses.
XXXII. But if this is the case, that one false idea can be entertained by the senses, you will find some one in a moment who will deny that anything can be perceived by the senses. And so, while we are silent, all perception and comprehension is done away with by the two principles laid down, one by Epicurus and the other by you. What is Epicurus's maxim?—If anything that appears to the senses be false, then nothing can be perceived. What is yours?—The appearances presented to the senses are false.—What is the conclusion? Even if I hold my tongue, it speaks for itself, that nothing can be perceived. I do not grant that, says he, to Epicurus. Argue then with him, as he is wholly at variance with you, but leave me alone, who certainly agree with you so far, that the senses are liable to error. Although nothing appears so strange to me, as that such things should be said, especially by Antiochus, to whom the propositions which I have just mentioned were thoroughly known. For although, if he pleases, any one may find fault with this, namely with our denying that anything can be perceived; at all events it is not a very serious reproof that we can have to endure. But as for our statement that some things are probable, this does not seem to you to be sufficient. Grant that it is not. At least we ought to escape the reproaches which are incessantly bandied about by you, “Can you, then, see nothing? can you hear nothing? is nothing evident to you?”
I explained just now, on the testimony of Clitomachus, in what manner Carneades intended those statements to be taken. Hear now, how the same things are stated by Clitomachus in that book which he dedicated to Caius Lucilius, the poet, after he had written on the same subject to Lucius Censorinus, the one, I mean, who was consul with Marcus Manilius; he then used almost these very words; for I am well acquainted with them, because the first idea and arrangement of those very matters which we are now discussing is contained in that book. He then uses the following language—
“The philosophers of the Academy are of opinion that there are differences between things of such a kind that some appear probable, and others the contrary. But that it is not a sufficient reason for one's saying that some of these can be [pg 072] perceived and that others cannot, because many things which are false are probable; but nothing false can be perceived and known. Therefore, says he, those men are egregiously wrong who say that the Academics deny the existence of the senses; for they have never said that there is no such thing as colour, or taste, or sound; the only point they argue for is, that there is not in them that peculiar characteristic mark of truth and certainty which does not exist anywhere else.”