§1. I conceive that according to the morality of Common Sense, an ultimate harmony between (1) Self-interest and (2) Virtue is assumed or postulated; so that the performance of duty and cultivation of Virtue generally may be regarded as a ``duty to self'', as being always conducive to the agent's true interest and well-being. But further, Common Sense (in modern Europe) recognises a strict duty of preserving one's own life, even when the prospect life offers is one in which pain preponderates over pleasure; it is, indeed, held to be right and praiseworthy to encounter certain death in the performance of Strict duty, or for the preservation of the life of another, or for any very important gain to society; but not merely in order to avoid pain to the agent. At the same time, within the limits fixed by this and other duties, Common Sense considers, I think, that it is a duty to seek our own happiness, except in so far as we can promote the welfare of others by sacrificing it. This ``due concern about our own interest or happiness'' may be called the Duty of Prudence. It should, however, be observed that---since it is less evident that men do not adequately desire their own greatest good, than that their efforts are not sufficiently well directed to its attainment---in conceiving Prudence as a Virtue or Excellence, attention is often fixed almost exclusively on its intellectual side. Thus regarded, Prudence may be said to be merely Wisdom made more definite by the acceptance of Self-interest as its sole ultimate end: the habit of calculating carefully the best means to the attainment of our own interest, and resisting all irrational impulses which may tend to perturb our calculations or prevent us from acting on them.