All goods, then, are either without or within the soul, and of these those in the soul are preferable, just as we distinguish them in the external courses; for wisdom, virtue, and pleasure are in the soul, and some or all of these are generally admitted to be the end pursued.
Now of things exist in the soul, some are states or faculties, others activities and changes.
Virtue
Let these, then, be assumed in this way; and as to virtue, that it is the best disposition or state or faculty concerned with anything of which there is a using or work.
This is clear from induction, since we assume the same in every case. For example, we speak of perfection (virtue) in a cloak; for there is both a certain work and a certain using, and its best state is its perfection (virtue). The same holds good for a ship, a house or other things also. Therefore, for the soul too; for there is some work which belong to it.
Work
Let the work, then, be better when the state in which the thing resides is better, and as the states stand in relation to one another so do their works. And each thing’s work is its end.
So it is clear from these that the work is better than the state; for the end as being an end is the best, since we took as end that which is best and ultimate, for the sake of which all the others exist.
It is clear, therefore, that the work is better than the state and the disposition. But a work is so called in two ways. For in some cases the work is different as compared with the using, for instance the work of the art of house-building is a house but not the act of building, and the work of medicine is heath but not the restoration of health or the treatment.
Using
but in other cases the work is identical with the using, for instance the work of sight is the act of seeing, and of mathematical science speculation. So it follows that in cases where the work is identical with the using, this is better than the state.
Having distinguished these matters, we may say that the same work belong to a thing and to its virtue, though not in the same way. For example, the work of the art of shoe-making and of the act of shoe-making is a shoe.
If, now, there is a certain virtue which belongs to the art of shoe-making and to a good shoe-maker, then its work is a good shoe. And the same holds in other cases too.
The work of the soul
Further, let the work of the soul be the production of life, and this lies in using and waking; for sleep is a kind of idleness and quietness.
So, as the work of the soul and of virtue is one and the same, the work of virtue must be a good life. This, then, is the perfect good, which was happiness.
And it is clear from the assumptions we made (for happiness was the major good, the objectives and the best goods are in the soul, while the happiness itself is either a state or an activity), that since the activity is better than the state and the best activity than the best state, and since virtue is the best state, then the activity of virtue must be the major thing in the soul.
Happiness
But happiness too was the major thing; happiness, therefore, is activity of a good soul. But as happiness was something perfect and there is such a life as to be both perfect and imperfect, and the same with virtue (for the one is complete, the other some part of), and the activity of imperfect things is imperfect, it follows that happiness must be activity of perfect life in accordance with perfect virtue.
Bibliography: Aristotle, Eudemian Ethics (1218b.32 to 1219a.39)
Translation: George Kotsalis