Art, then, as we said, is a certain formed faculty or habit of production with correct reasoning or calculation, and the contrary of this ( ἀτεχνία ) is a habit of production with incorrect calculation, the field of both being that which is variable.

In order to ascertain what prudence is, we will first ask who they are whom we call prudent.

It seems to be characteristic of a prudent man that he is able to deliberate well about what is good or expedient for himself, not with a view to some particular end, such as health or strength, but with a view to well-being or living well.

This is confirmed by the fact that we apply the name sometimes to those who deliberate well in some particular field, when they calculate well the means to some particular good end, in matters that do not fall within the sphere of art. So we may say, generally, that a man who can deliberate well is prudent.