by the law common to all things, that is to say, the right reason which pervades all things, and is identical with this Zeus, lord and ruler of all that is. And this very thing constitutes the virtue of the happy man and the smooth current of life, when all actions promote the harmony of the spirit dwelling in the individual man with the will of him who orders the universe. Diogenes then expressly declares the end to be to act with good reason in the selection of what is natural. Archedemus says the end is to live in the performance of all befitting actions. By the nature with which our life ought to be in accord, Chrysippus understands both universal nature and more particularly the nature of man, whereas Cleanthes takes the nature of the universe alone as that which should be followed, without adding the nature of the individual. And virtue, he holds, is a harmonious disposition, choice-worthy for its own sake and not from hope or fear or any external motive. Moreover, it is in virtue that happiness consists ; for virtue is the state of mind which tends to make the whole of life harmonious. When a rational being is perverted, this is due to the deceptiveness of external pursuits or sometimes to the influence of associates. For the starting-points of nature are never perverse. Virtue, in the first place, is in one sense the perfection of anything in general, say of a statue ; again, it may be non-intellectual, like health, or intellectual, like prudence. For Hecato says in his first book On the Virtues that some are scientific and based upon theory, namely, those which have a structure of theoretical principles, such as prudence