Aristotle, Nicomachean Ethics
H. Rackham, Ed.

[19]

If the other hand it be more correct to speak of the appetitive part of the soul also as rational, in that case it is the rational part which, as well as the whole soul, is divided into two, the one division having rational principle in the proper sense and in itself, the other obedient to it as a child to its father. [20]

Now virtue also is differentiated in correspondence with this division of the soul. Some forms of virtue are called intellectual virtues, others moral virtues: Wisdom or intelligence and Prudence¹ are intellectual, Liberality and Temperance are moral virtues. When describing a man's moral character we do not say that he is wise or intelligent, but gentle or temperate; but a wise man also is praised for his disposition² , and praiseworthy dispositions we term virtues.

Book 2

1. Virtue being, as we have seen, of two kinds, intellectual and moral, intellectual virtue is for the most part both produced and increased by instruction, and therefore requires experience and time; whereas moral or ethical virtue is the product of habit （ethos）, and has indeed derived its name, with a slight variation of form, from that word.³ 1. [2] And therefore it is clear that none of the moral virtues formed is engendered in us by nature, for no natural property can be altered by habit. For instance, it is the nature of a stone to move downwards, and it cannot be trained to move upwards, even though you should try to train it to do so by throwing it up into the air ten thousand times; nor can fire be trained to move downwards, nor can anything else that naturally behaves in one way be trained into a habit of behaving in another way. 1. [3] The virtues⁴ therefore are engendered in us neither by nature nor yet in violation of nature; nature gives us the capacity to receive them, and this capacity is brought to maturity by habit.1. [4]

Moreover, the faculties given us by nature are bestowed on us first in a potential form; we exhibit their actual exercise afterwards. This is clearly so with our senses: we did not acquire the faculty of sight or hearing by repeatedly seeing or repeatedly listening, but the other way about—because we had the senses we began to use them, we did not get them by using them. The virtues on the other hand we acquire by first having actually practised them, just as we do the arts. We learn an art or craft by doing the things that we shall have to do when we have learnt it⁵: for instance, men become builders by building houses, harpers by playing on the harp.