Perhaps, however, so much as this has scarcely ever been expressly maintained. What Plato in his _Republic_ and other writers on the same side have rather tried to prove, is not that at any particular moment duty will be, to every one on whom it may devolve, productive of more happiness than any other course of conduct; but rather that it is every one’s interest on the whole to choose the life of the virtuous man. But even this it is very difficult even to render probable: as will appear, I think, if we examine the lines of reasoning by which it is commonly supported.
To begin with Plato’s argument. He represents the soul of the virtuous man as a well-ordered polity of impulses, in which every passion and appetite is duly obedient to the rightful sovereignty of reason, and operates only within the limits laid down by the latter. He then contrasts the tranquil peace of such a mind with the disorder of one where a succession of baser impulses, or some ruling passion, lords it over reason: and asks which is the happiest, even apart from external rewards and punishments. But we may grant all that Plato claims, and yet be no further advanced towards the solution of the question before us. For here the issue does not lie between Reason and Passion, but rather--in Butler’s language--between Rational Self-love and Conscience. We are supposing the Egoist to have all his impulses under control, and are only asking how this control is to be exercised. Now we have seen that the regulation and organisation of life best calculated to attain the end of self-interest appears _prima facie_ divergent at certain points from that to which men in general are prompted by a sense of duty. In order to maintain Plato’s position it has to be shown that this appearance is false; and that a system of self-government, which under certain circumstances leads us to pain, loss, and death, is still that which self-interest requires. It can scarcely be said that our nature is such that only this anti-egoistic kind of regulation is possible; that the choice lies between this and none at all. It is easy to imagine a rational egoist, strictly controlling each of his passions and impulses--including his social sentiments--within such limits that its indulgence should not involve the sacrifice of some greater gratification: and experience seems to show us many examples of persons who at least approximate as closely to this type as any one else does to the ideal of the orthodox moralist. Hence if the regulation of Conscience be demonstrably the best means to the individual’s happiness, it must be because the order kept by Self-love involves a sacrifice of pleasure on the whole, as compared with the order kept by Conscience. And if this is the case, it would seem that it can only be on account of the special emotional pleasure attending the satisfaction of the moral sentiments, or special pain or loss of happiness consequent on their repression and violation.