Excellence, then, is a state concerned with choice, lying in a mean, relative to us, this being determined by reason and in the way in which the man of practical wisdom would determine it.
The true forms of government, therefore, are those in which the one, or the few, or the many, govern with a view to the common interest; but governments which rule with a view to the private interest, whether of the one or of the few, or of the many, are perversions. For the members of a state, if they are truly citizens, ought to participate in its advantages.
[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 enables us to achieve the end, Prudence makes us adopt the right means to the end.