Aristotle, Nicomachean Ethics
H. Rackham, Ed.

since those actions possess both these essentially pleasant qualities,¹ it therefore follows that the supremely happy man will require good friends, insomuch as he desires to contemplate actions that are good and that are his own, and the actions of a good man that is his friend are such. Also men think that the life of the happy man ought to be pleasant. Now a solitary man has a hard life, for it is not easy to keep up continuous activity by oneself; it is easier to do so with the aid of and in relation to other people. [6] The good man's activity therefore, which is pleasant in itself, will be more continuous if practised with friends²; and the life of the supremely happy should be continuously pleasant³ （for a good man, in virtue of his goodness, enjoys actions that conform with virtue and dislikes those that spring from wickedness, just as a skilled musician is pleased by good music and pained by bad）. [7] Moreover the society of the good may supply a sort of training in goodness, as Theognis⁴ remarks.

Again, if we examine the matter more fundamentally, it appears that a virtuous friend is essentially desirable for a virtuous man. For as has been said above, that which is essentially good is good and pleasing in itself to the virtuous man. And life is defined, in the case of animals, by the capacity for sensation; in the case of man, by the capacity for sensation and thought. But a capacity is referred to its activity, and in this its full reality consists. It appears therefore that life in the full sense is sensation or thought.But life is a thing good and pleasant in itself, for it is definite, and definiteness is a part of the essence of goodness, and what is essentially good is good for the good man, and hence appears to be pleasant to all men. [8] We must not argue from a vicious and corrupt life, or one that is painful, for such a life is indefinite, like its attributes.⁵ （The point as to pain will be clearer in the sequel.⁶） [9] But if life itself is good and pleasant （as it appears to be, because all men desire it, and virtuous and supremely happy men most of all, since their way of life is most desirable and their existence the most blissful） ; and if one who sees is conscious⁷ that he sees, one who hears that he hears, one who walks that he walks, and similarly for all the other human activities there is a faculty that is conscious of their exercise, so that whenever we perceive, we are conscious that we perceive, and whenever we think, we are conscious that we think, and to be conscious that we are perceiving or thinking is to be conscious that we exist （for existence, as we saw, is sense-perception or thought）;