C. D. Broad, Five Types of Ethical Theory, 1930 [177](B) EPISTEMOLOGICAL QUESTIONS. I have discussed the epistemology of ethics very fully in connexion with Hume, and can therefore afford to be brief here. Sidgwick's argument begins in the last paragraph of p. 33 in the Sixth Edition. It may be summarised as follows. We have come to the conclusion that there are judgments which use certain specific and indefinable ethical notions, such as right and ought. We may ascribe such judgments to a faculty of Moral Cognition, without thereby assuming that any of them are true. Can this faculty be identified with, or regarded as a species of, any of the familiar cognitive faculties which deal with non-ethical matters? In particular, is it analogous to Sense or to Reason? It is not plausible to suppose that all moral judgments are the results of reasoning from self-evident general principles to particular cases. On the contrary it is quite plausible to hold that the faculty of Moral Cognition primarily pronounces singular judgments on particular cases as they arise. And this might make it appear that this faculty is more analogous to Sense than to Reason. But (a) this suggests that it involves sensations or feelings, which might vary from man to man, and that there could be no question of truth or falsity and no real differences of opinion on ethical matters. And (b) even if we start with singular ethical judgments, we never remain content with them or regard them as ultimate. If I judge that X is wrong I always think it reasonable to be asked for a ground for my assertion. And [178] the ground would always take the form: "X has certain non-ethical characteristics C, and it is evident that anything which had these characteristics would be wrong." These general principles are reached from particular cases by acts of intuitive induction, and this is a typical act of Reason. Moreover, there are certain very abstract general principles which form an essential part of Ethics, though they do not suffice to tell us our duties in particular cases. An example is that it is wrong to give benefits to or impose sacrifices on A rather than B unless there be some ground, other than the mere numerical difference between A and B, for treating them differently. Such principles can be grasped only by Reason.
After what I have said in connexion with Hume I need make only the following comments. (a) The essential point is that Ethics involves both a priori concepts and a priori judgments; and these, by definition, are the work of Reason. We may therefore admit that Reason is essential in ethical cognition. But (b) analogy would suggest that it is not sufficient. In other departments of knowledge Reason does not form a priori concepts unless and until it is presented with suitable materials to reflect upon by Sense perception. Thus, e.g., it may well be that, unless our sensations had very often come in recurrent bundles, we should never have reached the a priori concept of Substance; and that, unless there had been a good deal of regularity in sense-perception, we should never have reached the a priori concept of Cause. It therefore seems likely that something analogous to sense-perception is necessary, though not sufficient, in ethical cognition. It is difficult to suppose that ordinary sense-perception can play the required part. But it does seem to me plausible to suppose that this part may be played by emotions of moral approval and [179] disapproval. The statement that X is wrong is not, in my opinion, a statement about my own or other men's emotions of disapproval; just as the statement that X causes Y is not, in my opinion, a statement about the regular sequence of Y-like events on X-like events. But it seems to me arguable that wrongness would never have been recognised by Reason without the stimulus and suggestion of the emotion of disapproval and that causation would never have been recognised by Reason without the stimulus and suggestion of perceived regular sequence. I do not think that this is in any way incompatible with the fact that now, in many cases, the judgment that so-and-so is wrong may precede and causally determine an emotion of moral disapproval towards so-and-so.
PSYCHOLOGICAL QUESTIONS ABOUT MOTIVES AND VOLITIONS.