As an example, again, of thinkers who, while recognising in human nature a disinterested regard for duty or virtue as such, still consider that self-love is a proper and legitimate motive to right conduct, we may refer to Butler and his disciples. Butler regards “reasonable self-love” as not merely a normal motive to human action, but as being--no less than conscience--a “chief or superior principle in the nature of man”; so that an action “becomes unsuitable” to this nature, if the principle of self-love be violated. Accordingly the aim of his teaching is not to induce men to choose duty rather than interest, but to convince them that there is no inconsistency between the two; that self-love and conscience lead “to one and the same course of life.”
This intermediate doctrine appears to me to be more in harmony with the common sense of mankind on the whole than either of the extreme views before contrasted. But I do not conceive that any one of the three positions is inconsistent with fundamental assumptions of the Intuitional method. Even those who hold that human beings cannot reasonably be expected to conform to moral rules disinterestedly, or from any other motive than that supplied by the sanctions divinely attached to them, still commonly conceive God as supreme Reason, whose laws must be essentially reasonable: and so far as such laws are held to be cognisable by the ‘light of nature’--so that morality, as Locke says, may be placed among demonstrative sciences--the method of determining them will be none the less intuitional because it is combined with the belief that God will reward their observance and punish their violation. On the other hand those who hold that regard for duty as duty is an indispensable condition of acting rightly, would generally admit that acting rightly is not adequately defined as acting from a pure desire to act rightly; that though, in a certain sense, a man who sincerely desires and intends to act rightly does all he can, and completely fulfils duty, still such a man may have a wrong judgment as to the particulars of his duty, and therefore, in another sense, may act wrongly. If this be admitted, it is evident that, even on the view that the desire or resolution to fulfil duty as such is essential to right action, a distinction between two kinds of rightness is required; which we may express by saying that an act is--on this view--“formally”[163] right, if the agent in willing is moved by pure desire to fulfil duty or chooses duty for duty’s sake; “materially” right, if he intends the right particular effects. This distinction being taken, it becomes plain that there is no reason why the same principles and method for determining material rightness, or rightness of particular effects, should not be adopted by thinkers who differ most widely on the question of formal rightness; and it is, obviously, with material rightness that the work of the systematic moralist is mainly concerned.