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.
They - Young People have exalted notions, because they have not been humbled by life or learned its necessary limitations; moreover, their hopeful disposition makes them think themselves equal to great things - and that means having exalted notions. They would always rather do noble deeds than useful ones: Their lives are regulated more by moral feeling than by reasoning - all their mistakes are in the direction of doing things excessively and vehemently. They overdo everything - they love too much, hate too much, and the same with everything else.
You'll understand what life is if you think about the act of dying. When I die, how will I be different from the way I am right now? In the first moments after death, my body will be scarcely different in physical terms than it was in the last seconds of life, but I will no longer move, no longer sense, nor speak, nor feel, nor care. It's these things that are life. At that moment, the psyche takes flight in the last breath.
The good lawgiver should inquire how states and races of men and communities may participate in a good life, and in the happiness which is attainable by them.
And it is characteristic of man that he alone has any sense of good and evil, of just and unjust, and the like, and the association of living beings who have this sense makes family and a state.
Whereas young people become accomplished in geometry and mathematics, and wise within these limits, prudent young people do not seem to be found. The reason is that prudence is concerned with particulars as well as universals, and particulars become known from experience, but a young person lacks experience, since some length of time is needed to produce it.
But obviously a state which becomes progressively more and more of a unity will cease to be a state at all. Plurality of numbers is natural in a state; and the farther it moves away from plurality towards unity, the less of a state it becomes and the more a household, and the household in turn an individual.