What then can this be? not mere life, because that plainly is shared with him even by vegetables, and we want what is peculiar to him. We must separate off then the life of mere nourishment and growth, and next will come the life of sensation: but this again manifestly is common to horses, oxen, and every animal. There remains then a kind of life of the Rational Nature apt to act: and of this Nature there are two parts denominated Rational, the one as being obedient to Reason, the other as having and exerting it. Again, as this life is also spoken of in two ways,[19] we must take that which is in the way of actual working, because this is thought to be most properly entitled to the name. If then the work of Man is a working of the soul in accordance with reason, or at least not independently of reason, and we say that the work of any given subject, and of that subject good of its kind, are the same in kind (as, for instance, of a harp-player and a good harp-player, and so on in every case, adding to the work eminence in the way of excellence; I mean, the work of a harp-player is to play the harp, and of a good harp-player to play it well); if, I say, this is so, and we assume the work of Man to be life of a certain kind, that is to say a working of the soul, and actions with reason, and of a good man to do these things well and nobly, and in fact everything is finished off well in the way of the excellence which peculiarly belongs to it: if all this is so, then the Good of Man comes to be “a working of the Soul in the way of Excellence,” or, if Excellence admits of degrees, in the way of the best and most perfect Excellence. And we must add, ἐν βίῳ τελείῳ;[20] for as it is not one swallow or one fine day that makes a spring, so it is not one day or a short time that makes a man blessed and happy. Let this then be taken for a rough sketch of the Chief Good: since it is probably the right way to give first the outline, and fill it in afterwards. And it would seem that any man may improve and connect what is good in the sketch, and that time is a good discoverer and co-operator in such matters: it is thus in fact that all improvements in the various arts have been brought about, for any man may fill up a deficiency. You must remember also what has been already stated, and not seek for exactness in all matters alike, but in each according to the subject-matter, and so far as properly belongs to the system. The carpenter and geometrician, for instance, enquire into the right line in different fashion: the former so far as he wants it for his work, the latter enquires into its nature and properties, because he is concerned with the truth. So then should one do in other matters, that the incidental matters may not exceed the direct ones.