But first we must consider in what the good life consists and how it is to be acquired, whether all who receive the epithet 'happy' become so by nature (as we become tall, short, or of different complexions), or by teaching (happiness being a sort of science), or by some sort of discipline for men acquire many qualities neither by nature nor by teaching but by habituation, bad qualities if they are habituated to the bad, good if to the good.