Nicomachean Ethics

​But perhaps to say that happiness is the best good appears to be something agreed upon, but it is desired that what it is still be expressed more clearly. Perhaps this might indeed come about if the function (ergon) of man were grasped. For just as for a flute-player, a sculptor, and every artisan, and generally for all who have some function and activity, the good and the “well” seem to reside in their function, so it would seem to be also for man, if indeed there is some function of his. Are there then certain functions and activities of a carpenter and a shoemaker, but of man is there none, but is he by nature born idle? Or, just as there appears to be some function of eye, hand, foot, and generally of each of the parts, so also for man, besides all these, should one posit some function? What then indeed could this ever be? For living appears to be common even to plants, but what is sought is what is peculiar. Therefore, we must set aside the life of nutrition and growth. And next would be a certain sensitive life, but this too appears to be common to horse, ox, and every animal. There remains, then, a certain active life of that which has reason; and of this, one part is obedient to reason, while the other possesses reason and thinks. And since this life also is spoken of in two ways, we must posit the one in activity; for this seems to be spoken of in a more proper sense. And if the function of man is an activity of soul in accordance with reason or not without reason, and we say that the function of a certain kind of person and of a serious person of that kind is the same in genus, just as of a lyre-player and of a serious lyre-player, and absolutely so in all cases, with the superiority in accordance with virtue being added to the function (for the function of a lyre-player is to play the lyre, and of a serious one to do it well); if this is so, the human good turns out to be an activity of soul in accordance with virtue, and if there are more virtues than one, in accordance with the best and most complete. And further, in a complete life. For one swallow does not make a spring, nor does one day; and so neither does one day or a short time make a man blessed and happy. Let the good, then, have been outlined in this way; for perhaps we must first sketch it, and then later fill in the details. And it would seem to be open to anyone to advance and articulate what is well outlined, and that time is a good discoverer or co-worker in such things; whence also the advances in the arts have occurred; for it belongs to anyone to add what is lacking. But we must also remember what has been said before, and not demand precision in all things alike, but in each according to the underlying matter and to such an extent as is proper to the inquiry. For both a carpenter and a geometrician seek a right angle differently; the former insofar as it is useful for his work, the latter as to what it is or what kind of thing, for he is a spectator of truth. In the same way, then, we must act in other things, so that the main works may not be outnumbered by the side-issues. And we must not demand the cause in all things alike, but it is sufficient in some cases that the fact “that it is so” be well shown, as indeed in the case of principles; and the fact “that it is so” is a first thing and a principle. And of principles, some are contemplated by induction, some by perception, some by a certain habituation, and others in other ways. And we must try to pursue each in the way they are by nature, and make a serious effort that they be well defined; for they have great weight for what follows. For the principle seems to be more than half of the whole, and many of the things being sought become clear through it.