I might here pause, without attempting to pass a judgment on what I have described. The extreme difficulty of the subject would be my excuse, but I shall not avail myself of it; and I had rather that my readers, clearly perceiving my object, should refuse to follow me than that I should leave them in suspense. The principle of interest rightly understood is not a lofty one, but it is clear and sure. It does not aim at mighty objects, but it attains without excessive exertion all those at which it aims. As it lies within the reach of all capacities, everyone can without difficulty apprehend and retain it. By its admirable conformity to human weaknesses, it easily obtains great dominion; nor is that dominion precarious, since the principle checks one personal interest by another, and uses, to direct the passions, the very same instrument which excites them. The principle of interest rightly understood produces no great acts of self-sacrifice, but it suggests daily small acts of self-denial. By itself it cannot suffice to make a man virtuous, but it disciplines a number of citizens in habits of regularity, temperance, moderation, foresight, self-command; and, if it does not lead men straight to virtue by the will, it gradually draws them in that direction by their habits. If the principle of interest rightly understood were to sway the whole moral world, extraordinary virtues would doubtless be more rare; but I think that gross depravity would then also be less common. The principle of interest rightly understood perhaps prevents some men from rising far above the level of mankind; but a great number of other men, who were falling far below it, are caught and restrained by it. Observe some few individuals, they are lowered by it; survey mankind, it is raised. I am not afraid to say that the principle of interest, rightly understood, appears to me the best suited of all philosophical theories to the wants of the men of our time, and that I regard it as their chief remaining security against themselves. Towards it, therefore, the minds of the moralists of our age should turn; even should they judge it to be incomplete, it must nevertheless be adopted as necessary.