Aristotle, Nicomachean Ethics
H. Rackham, Ed.

and the tastes of youth change quickly. Also the young are prone to fall in love, as love is chiefly guided by emotion, and grounded on pleasure; hence they form attachments quickly and give them up quickly, often changing before the day is out.

The young do desire to pass their time in their friend's company, for that is how they get the enjoyment of their friendship. 3. [6]

The perfect form of friendship is that between the good, and those who resemble each other in virtue. For these friends wish each alike the other's good in respect of their goodness,¹ and they are good in themselves; but it is those who wish the good of their friends for their friends' sake who are friends in the fullest sense, since they love each other for themselves and not accidentally.² Hence the friendship of these lasts as long as they continue to be good; and virtue is a permanent quality. And each is good relatively to his friend as well as absolutely, since the good are both good absolutely and profitable to each other. And each is pleasant in both ways also, since good men are pleasant both absolutely and to each other; for everyone is pleased by his own actions, and therefore by actions that resemble his own, and the actions of all good men are the same or similar.— 3. [7] Such friendship is naturally permanent, since it combines in itself all the attributes that friends ought to possess. All affection is based on good