In the long run, the public interest depends on private virtue.

From The rediscovery of character: private virtue and public policy by James Q. Wilson in the Fall of 1985.

By virtue, I mean habits of moderate action; more specifically, acting with due restraint on one's impulses, due regard for the rights of others, and reasonable concern for distant consequences. Scarcely anyone favors bad character or a lack of virtue, but it is all too easy to deride a policy of improving character by assuming that this implies a nation of moralizers delivering banal homilies to one another.  

 

Virtue is not learned by precept, however; it is learned by the regular repetition of right actions. We are induced to do the right thing with respect to small matters, and in time we persist in doing the right thing because now we have come to take pleasure in it. By acting rightly with respect to small things, we are more likely to act rightly with respect to large ones. If this view sounds familiar, it should; it is Aristotle's. Let me now quote him directly: "We become just by the practice of just actions, self-controlled by exercising self-control." 
 
Seen in this way, there is no conflict between economic thought and moral philosophy: The latter simply supplies a fuller statement of the uses to which the former can and should be put. We want our families and schools to induce habits of right conduct; most parents and teachers do this by arranging the incentives confronting youngsters in the ordinary aspects of their daily lives so that right action routinely occurs. What economics neglects is the important subjective consequence of acting in accord with a proper array of incentives: people come to feel pleasure in right action and guilt in wrong action. These feelings of pleasure and pain are not mere "tastes" that policy analysts should take as given; they are the central constraints on human avarice and sloth, the very core of a decent character. A course of action cannot be evaluated simply in terms of its cost-effectiveness, because the consequence of following a given course--if it is followed often enough and regularly enough--is to teach those who follow it what society thinks is right and wrong. Conscience and character, naturally, are not enough. Rules and rewards must still be employed; indeed, given the irresistible appeal of certain courses of action--such as impoverishing future generations for the benefit of the present one--only some rather draconian rules may suffice. But for most social problems that deeply trouble us, the need is to explore, carefully and experimentally, ways of strengthening the formation of character among the very young. In the long run, the public interest depends on private virtue.