And, indeed, if the custom of man could speak, this would be its language. That its first beginnings were, as it were, beginnings of desire that it might preserve itself in that nature in which it had been born. For it had not yet been sufficiently explained what nature desired above all things. Let it therefore be explained. What else then will be understood but that no part of nature is to be neglected? And if there is nothing in it besides reason, then the chief good must be in virtue alone. But if there is also body, then will that explanation of nature have caused us to abandon the belief which we held before the explanation. Is it, then, being in a manner suitable to nature to abandon nature? As some philosophers do, when having begun with the senses they have seen something more important and divine, and then abandoned the senses; so, too, these men, when they had beheld the beauty of virtue developed in its desire for particular things, abandoned everything which they had seen for the sake of virtue herself, forgetting that the whole nature of desirable things was so extensive that it remained from beginning to end; and they do not understand that they are taking away the very foundations of these beautiful and admirable things. XVI. Therefore, all those men appear to me to have made a blunder who have pronounced the chief good to be to live honourably. But some have erred more than others,—Pyrrho above all, who, having fixed on virtue as the chief good, refuses to allow that there is anything else in the world deserving of being desired; and, next to him, Aristo, who did not, indeed, venture to leave nothing else to be desired, but who introduced influence, by which a wise man might be excited, and desire whatever occurred to his mind, and whatever even appeared so to occur. He was more right than Pyrrho, inasmuch as he left man some kind of desire; but worse than the rest, inasmuch as he departed wholly from nature: but the Stoics, because they place the chief good in virtue alone, resemble these men: but inasmuch as they seek for a principle of duty, they are superior to Pyrrho; and as they do not admit the desire of those objects which offer themselves to the imagination, they are more correct than Aristo; but, inasmuch as they do not add the things which they admit to be adopted by nature, and to be worthy of being chosen for their own sakes, to the chief good, they here desert nature, and are in some degree not different from Aristo: for he invented some strange kinds of occurrences; but these men recognise, indeed, the principles of nature, but still they disconnect them from the perfect and chief good; and when they put them forward, so that there may be some selection of things, they appear to follow nature; but when they deny that they have any influence in making life happy, they again abandon nature.