Aristotle, Nicomachean Ethics
H. Rackham, Ed.

since we always choose it for its own sake and never as a means to something else; whereas honor, pleasure, intelligence, and excellence in its various forms, we choose indeed for their own sakes （since we should be glad to have each of them although no extraneous advantage resulted from it）, but we also choose them for the sake of happiness, in the belief that they will be a means to our securing it. But no one chooses happiness for the sake of honor, pleasure, etc., nor as a means to anything whatever other than itself. [6]

The same conclusion also appears to follow from a consideration of the self-sufficiency of happiness—for it is felt that the final good must be a thing sufficient in itself. The term self-sufficient, however, we employ with reference not to oneself alone, living a life of isolation, but also to one's parents and children and wife, and one's friends and fellow citizens in general, since man is by nature a social being.¹ [7] On the other hand a limit has to be assumed in these relationships; for if the list be extended to one's ancestors and descendants and to the friends of one's friends, it will go on ad infinitum. But this is a point that must be considered later on; we take a self-sufficient thing to mean a thing which merely standing by itself alone renders life desirable lacking in nothing,² and such a thing we deem happiness to be. [8] Moreover, we think happiness the most desirable of all good things without being itself reckoned as one among the rest³; for if it were so reckoned, it is clear that we should consider it more desirable when even the smallest of other good things were combined with it, since this addition would result in a larger total of good, and of two goods the greater is always the more desirable.

Happiness, therefore, being found to be something final and self-sufficient, is the End at which all actions aim. [9]

To say however that the Supreme Good is happiness will probably appear a truism; we still require a more explicit account of what constitutes happiness. [10] Perhaps then we may arrive at this by ascertaining what is man's function. For the goodness or efficiency of a flute-player or sculptor or craftsman of any sort, and in general of anybody who has some function or business to perform, is thought to reside in that function; and similarly it may be held that the good of man resides in the function of man, if he has a function. [11]

Are we then to suppose that, while the carpenter and the shoemaker have definite functions or businesses belonging to them, man as such has none, and is not designed by nature to fulfil any function? Must we not rather assume that, just as the eye, the hand, the foot and each of the various members of the body manifestly has a certain function of its own, so a human being also has a certain function over and above all the functions of his particular members? [12] What then precisely can this function be? The mere act of living appears to be shared even by plants, whereas we are looking for the function peculiar to man;