Book 2
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 itOr possibly For things that we have to learn to do [in contrast with things that we do by nature], we learn by doing them.: for instance, men become builders by building houses, harpers by playing on the harp. Similarly we become just by doing just acts, temperate by doing temperate acts, brave by doing brave acts.
5
This truth is attested by the experience of states: lawgivers make the citizens good by training them in habits of right action—this is the aim of all legislation, and if it fails to do this it is a failure; this is what distinguishes a good form of constitution from a bad one.
6
Again, the actions from or through which any virtue is produced are the same as those through which it also is destroyed—just as is the case with skill in the arts, for both the good harpers and the bad ones are produced by harping, and similarly with builders and all the other craftsmen: as you will become a good builder from building well, so you will become a bad one from building badly.
