For desires are insatiable, and ruin not only individuals but entire families, and often overturn the whole state. From desires arise hatred, dissensions, quarrels, seditions, wars. Nor is it only out of doors that these passions vent themselves, nor is it only against others that they run with blind violence; but they are often shut up, as it were, in the mind, and throw that into confusion with their disagreements. And the consequence of this is, to make life thoroughly wretched; so that the wise man is the only one who, having cut away all vanity and error, and removed it from him, can live contented within the boundaries of nature, without melancholy and without fear. For what diversion can be either more useful or more adapted for human life than that which Epicurus employed? For he laid it down that there were three kinds of desires; the first, such as were natural and necessary; the second, such as were natural but not necessary; the third, such as were neither natural nor necessary. And these are all such, that those which are necessary are satisfied without much trouble or expense: even those which are natural and not necessary, do not require a great deal, because nature itself makes the riches, which are sufficient to content it, easy of acquisition and of limited quantity: but as for vain desires, it is impossible to find any limit to, or any moderation in them. XIV. But if we see that the whole life of man is thrown into disorder by error and ignorance; and that wisdom is the only thing which can relieve us from the sway of the passions and the fear of danger, and which can teach us to bear the injuries of fortune itself with moderation, and which shows us all the ways which lead to tranquillity and peace; what reason is there that we should hesitate to say that wisdom is to be sought for the sake of pleasure, and that folly is to be avoided on account of its annoyances? And on the same principle we shall say that even temperance is not to be sought for its own sake, but because it brings peace to the mind, and soothes and tranquillizes them by what I may call a kind of concord. For temperance is that which warns us to follow reason in desiring or avoiding anything. Nor is it sufficient to decide what ought to be done, and what ought not; but we must adhere to what has been decided. But many men, because they are enfeebled and subdued the moment pleasure comes in sight, and so are unable to keep and adhere to the determination they have formed, give themselves up to be bound hand and foot by their lusts, and do not foresee what will happen to them; and in that way, on account of some pleasure which is trivial and unnecessary, and which might be procured in some other manner, and which they could dispense with without annoyance, incur terrible diseases, and injuries, and disgrace, and are often even involved in the penalties of the legal tribunals of their country.