The two essentials of justice are (1) the desire to punish some one, and (2) the notion or belief that harm has been done to some definite individual or individuals. Now, it appears to the author that the desire to punish is a spontaneous outgrowth of two sentiments, both natural, and, it may be, instinctive; the impulse of _self-defence_, and the feeling of _sympathy_. We naturally resent, repel, and retaliate, any harm done to ourselves and to any one that engages our sympathies. There is nothing moral in mere resentment; the moral part is the subordination of it to our social regards. We are moral beings, in proportion as we restrain our private resentment whenever it conflicts with the interests of society. All moralists agree with Kant in saying that no act is right that could not be adopted as a law by all rational beings (that is, consistently with the well-being of society). There is in Justice a rule of conduct, and a right on the part of some one, which right ought to be enforced by society. If it is asked why society _ought_ to enforce the right, there is no answer but the general utility. If that expression seem feeble and inadequate to account for the energy of retaliation inspired by injustice, the author asks us to advert to the extraordinarily important and impressive kind of utility that is concerned. The interest involved is _security_, to every one's feelings the most vital of all interests. All other earthly benefits needed by one person are not needed by another; and many of them can, if necessary, be cheerfully foregone, or replaced by something else; but security no human being can possibly do without; on it we depend for all our immunity from evil, and for the whole value of all and every good, beyond the passing moment. Now, this most indispensable of all necessaries, after physical nutriment, cannot be had unless the machinery for providing it is kept unintermittedly in active play. Our notion, therefore, of the claim we have on our fellow-creatures to join in making safe for us the very groundwork of our existence, gathers feelings around it so much more intense than those concerned in any of the more common cases of utility, that the difference in degree (as is often the case in psychology) becomes a real difference in kind. The claim assumes that character of absoluteness, that apparent infinity, and incommensurability with all other considerations, which constitute the distinction between the feeling of right and wrong, and that of ordinary expediency and inexpediency.