Here then we have a second Intuitional Method: of which the fundamental assumption is that we can discern certain general rules with really clear and finally valid intuition. It is held that such general rules are implicit in the moral reasoning of ordinary men, who apprehend them adequately for most practical purposes, and are able to enunciate them roughly; but that to state them with proper precision requires a special habit of contemplating clearly and steadily abstract moral notions. It is held that the moralist’s function then is to perform this process of abstract contemplation, to arrange the results as systematically as possible, and by proper definitions and explanations to remove vagueness and prevent conflict. It is such a system as this which seems to be generally intended when Intuitive or _a priori_ morality is mentioned, and which will chiefly occupy us in Book iii.
§ 4. By philosophic minds, however, the ‘Morality of Common Sense’ (as I have ventured to call it), even when made as precise and orderly as possible, is often found unsatisfactory as a system, although they have no disposition to question its general authority. It is found difficult to accept as scientific first principles the moral generalities that we obtain by reflection on the ordinary thought of mankind, even though we share this thought. Even granting that these rules can be so defined as perfectly to fit together and cover the whole field of human conduct, without coming into conflict and without leaving any practical questions unanswered,--still the resulting code seems an accidental aggregate of precepts, which stands in need of some rational synthesis. In short, without being disposed to deny that conduct commonly judged to be right is so, we may yet require some deeper explanation _why_ it is so. From this demand springs a third species or phase of Intuitionism, which, while accepting the morality of common sense as in the main sound, still attempts to find for it a philosophic basis which it does not itself offer: to get one or more principles more absolutely and undeniably true and evident, from which the current rules might be deduced, either just as they are commonly received or with slight modifications and rectifications.[90]