Prudence as well as Moral Virtue determines the complete performance of a man's proper function: Virtue ensures the rightness of the end we aim at, Prudence ensures the rightness of the means we adopt to gain that end.
[the virtues] cannot exist without Prudence. A proof of this is that everyone, even at the present day, in defining Virtue, after saying what disposition it is [i.e. moral virtue] and specifying the things with which it is concerned, adds... ...
A wise person doesn't put themselves in unnecessary danger, as there are few things they care deeply enough about; but in big crises, they are willing to give their life, knowing that sometimes life isn't worth living under certain conditions.
If a man of good natural disposition acquires Intelligence [as a whole], then he excels in conduct, and the disposition which previously only resembled Virtue, will now be Virtue in the true sense. Hence just as with the faculty of... ...
[Prudence] is the virtue of that part of the intellect [the calculative] to which it belongs; and . . . our choice of actions will not be right without Prudence any more than without Moral Virtue, since, while Moral Virtue... ...
So virtue is a purposive disposition, lying in a mean that is relative to us and determined by a rational principle, and by that which a prudent man would use to determine it. It is a mean between two kinds... ...
...virtue is not merely a state in conformity with the right principle, but one that implies the right principle; and the right principle in moral conduct is prudence.
