And on this account all men suppose that the happy life is a pleasant one, and that happiness involves pleasure: and the supposition is reasonable; for no exercise of a faculty is complete if it be impeded; but happiness we reckon among complete things; and so, if he is to be happy, a man must have the goods of the body and external goods and good fortune, in order that the exercise of his faculties may not be impeded. And those who say that though a man be put to the rack and overwhelmed by misfortune, he is happy if only he be good, whether they know it or not, talk nonsense.

Because fortune is a necessary condition, some people consider good fortune to be identical with happiness; but it is not really so, for good fortune itself, if excessive, is an impediment, and is then, perhaps, no longer to be called good fortune; for good fortune can only be defined by its relation to happiness.

Again, the fact that all animals and men pursue pleasure is some indication that it is in some way the highest good: