... famous essay on "Perpetual Peace":
"Many say a republic would have to be a nation of angels, because men with their selfish inclinations are not capable of a constitution of such sublime form. But precisely with these inclinations nature comes to the aid of the general will established on reason, which is revered even though impotent in practice. Thus it is only a question of a good organization of the state (which does lie in man's power), whereby the powers of each selfish inclination are so arranged in opposition that one moderates or destroys the ruinous effect of the other. The consequence for reason is the same as if none of them existed, and man is forced to be a good citizen even if not a morally good person.... but is his observations of a Europe seemingly in perpetual warfare relevant today, in Britain, in Wales ?
The problem of organizing a state, however hard it may seem, can be solved even for a race of devils, if only they are intelligent. The problem is: 'Given a multitude of rational beings requiring universal laws for their preservation, but each of whom is secretly inclined to exempt himself from them, to establish a constitution in such a way that, although their private intentions conflict, they check each other, with the result that their public conduct is the same as if they had no such intentions.'
A problem like this must be capable of solution; it does not require that we know how to attain the moral improvement of men but only that we should know the mechanism of nature in order to use it on men, organizing the conflict of the hostile intentions present in a people in such a way that they must compel themselves to submit to coercive laws. Thus a state of peace is established in which laws have force."