right is betrayed too. From which fault betrayals of friendships and of republics often originate. It cannot, therefore be doubted, that no rule of wisdom can possibly be false; and it ought not to be enough for the wise man that it is not false, but it ought also to be steady, durable, and lasting; such as no arguments can shake. But none can either be, or appear such, according to the principle of those men who deny that those perceptions in which all rules originate are in any respect different from false ones; and from this assertion arose the demand which was repeated by Hortensius, that you would at least allow that the fact that nothing can be perceived has been perceived by the wise man. But when Antipater made the same demand, and argued that it was unavoidable that the man who affirmed that nothing could be perceived should nevertheless admit that this one thing could be perceived,—namely, that nothing else could,—Carneades resisted him with great shrewdness. For he said that this admission was so far from being consistent with the doctrine asserted, that it was above all others incompatible with it: for that a man who denied that there was anything which could be perceived excepted nothing. And so it followed of necessity, that even that very thing which was not excepted, could not be comprehended and perceived in any possible manner.
Antiochus, on this topic, seems to press his antagonist more closely. For since the Academicians adopted that rule, (for you understand that I am translating by this word what they call δόγμα,) that nothing can be perceived, he urged that they ought not to waver in their rule as in other matters, especially as the whole of their philosophy consisted in it: for that the fixing of what is true and false, known and unknown, is the supreme law of all philosophy. And since they adopted this principle, and wished to teach what ought to be received by each individual, and what rejected, undoubtedly, said he, they ought to perceive this very thing from which the whole judgment of what is true and false arises. He urged, in short, that there were these two principal objects in philosophy, the knowledge of truth, and the attainment of the chief good; and that a man could not be wise who was ignorant of either the beginning of knowledge, or of the end of desire, so as not to know either where to start from, or
