Let us then proceed, said he, since we have digressed from these first principles of nature, which everything which follows ought to be in harmony with. But this is the first division of the subject. A thing is said to be estimable: for so we may, I think, call that which is either itself in accordance with nature, or else which is the efficient cause of something of such a character that it is worthy of being selected because it has in it some weight worth appreciating, which he calls ἀχία; and, on the other hand, something not estimable, which is the contrary of the preceding. The first principles, therefore, being laid down, that those things which are according to nature are to be chosen for their own sakes, and those which are contrary to it are in like manner to be rejected; the first duty (for that is how I translate the word καθῆκον) is, for a man to preserve himself in his natural condition; next to that, to maintain those things which are in accordance with nature, and reject what is opposite to it; and when this principle of selection and rejection has been discovered, then follows selection in accordance with duty; and then that third kind, which is perpetual, and consistent to the end, and corresponding to nature, in which there first begins to be a proper understandingof what there is which can be truly called good. For the first attraction of man is to those things which are according to nature. But as soon as he has received that intelligence, or perhaps I should say, notion, which they call ἔννοια, and has seen the order and, if I may so say, the harmony in which things are to be done, he then estimates it at a higher value than all the things which he loved at first; and by this knowledge, and by reasoning, he comes to such a conclusion that he decides that the chief good of man, which deserves to be praised and desired for its own sake, is placed in what the Stoics call ὁμολογία, and we agreement, if you approve of this translation of the term; as therefore it is in this that that good is placed to which all things [which are done honourably] are to be referred, and honour itself, which is reckoned among the goods, although it is only produced subsequently, still this alone deserves to be sought for on account of its intrinsic power and worth; but of those things which are the principal natural goods there is not one which is to be sought for its own sake.
But as those things which I have called duties proceed from the first principles of nature, they must necessarily be referred to them; so that it may be fairly said that all duties are referred to this end, of arriving at the principles of nature; not, however, that this is the highest of all goods, because there is no such thing as honourable action in the first attractions of nature; for that is what follows, and arises subsequently, as I have said before. But still it is according to nature, and encourages us to desire itself much more than all those things which have been previously mentioned. But, first of all, we must remove a mistake, that no one may think that it follows that there are two supreme goods. For as, if it were the purpose of any one to direct an arrow or a spear straight at any object, just as we have said that there is an especial point to be aimed at in goods,—the archer ought to do all in his power to aim straight at the target, and the other man ought also to do his endeavour to hit the mark, and gain the end which he has proposed to himself: let this then which we call the chief good in life be, as it were, his mark; and his endeavour to hit it must be furthered by careful selection, not by mere desire.