Why is there this reluctance to accord to moral experience its full metaphysical significance? There can be little doubt, I think, that the leading influence is the immense authority which belongs, for most thinkers, to the belief which runs directly counter to the implications of moral experience, the belief in the intelligibility of reality. The belief may be taken to be guaranteed by the cumulative success of scientific inquiry, or it may be supposed to be an actual postulate implied in all thinking. In either case the security of its lodgment in human experience is regarded as well-nigh indisputable. Now when against this deep-seated belief are set the implications of an experience which, after all, is of but sporadic occurrence in human life, an experience which, although acknowledged to occur as a matter of fact, is not visibly embedded in the very structure of human nature (as a necessary postulate of thought is embedded), it is hardly surprising that if, in the interests of consistency, one side must give way, the 'moral' is felt to be the side which must be sacrificed. (It is only justice to add, however, that the presence of moral experience, however sporadic, is constantly felt to be embarrassing. Hence the divers attempts to concoct an interpretation of morality for which the freedom of 'open possibilities' is not required - a forlorn hope indeed, but natural enough if both morality and an 'intelligible reality' are felt to have inescapable claims).
These considerations suggest a line of treatment for our problem which, if successful, should be a good deal more effective in establishing the reality of the 'ought' than any re-hash of the arguments against the sceptical analysis of moral experience. Is it not possible, we must ask, that moral experience too may be 'visibly embedded in the very structure of human nature'? If this can be shown, if moral experience can be exhibited as a permanent and indefeasible element in the kind of experience which man has, then it becomes manifestly impossible to ignore or gloss over the implications of moral experience in the construction of metaphysical theory. Its claim to recognition will be on the same footing as the claim of 'thinking' experience. And if these two claims in the end prove incompatible (which we have, in earlier chapters, seen reasons for doubting) there will be no option but frankly to admit ourselves saddled with a metaphysical dualism.
My argument 'in defence of the ought' will, therefore, pursue the following course. I shall try to show that the psychological situation in which moral experience occurs (or in which 'oughtness' is apprehended) is one of definitely assignable conditions, which conditions are permanently rooted in the nature of man: that, accordingly, so long as human nature is what it is, recognition of 'oughtness' must remain an inseparable element of it. I shall not, I may add, be propounding any very novel doctrine. In large part I shall follow the account given by T. H. Green of the setting of the moral principle in the economy of human nature.1 But if this view (at present, one fears, almost without disciples) can be established, the significance of it within our present context of thought will be, I think, very great indeed.
1 It will be observed that I regard it as possible to disentangle the essential truth of Green's moral theory from its unhappy relations with the 'eternal self-consciousness'.