§4. But the question may be raised, whether it is legitimate to take for granted (as I have hitherto been doing) the existence of such intuitions? And, no doubt, there are persons who deliberately deny that reflection enables them to discover any such phenomenon in their conscious experience as the judgment or apparent perception that an act is in itself right or good, in any other sense than that of being the right or fit means to the attainment of some ulterior end. I think, however, that such denials are commonly recognised as paradoxical, and opposed to the common experience of civilised men:---at any rate if the psychological question, as to the existence of such moral judgments or apparent perceptions of moral qualities, is carefully distinguished from the ethical question as to their validity, and from what we may call the `psychogonical' question as to their origin. The first and second of these questions are sometimes confounded, owing to an ambiguity in the use of the term ``intuition''; which has sometimes been understood to imply that the judgment or apparent perception so designated is true. I wish therefore to say expressly, that by calling any affirmation as to the rightness or wrongness of actions ``intuitive'', I do not mean to prejudge the question as to its ultimate validity, when philosophically considered: I only mean that its truth is apparently known immediately, and not as the result of reasoning. I admit the possibility that any such ``intuition'' may turn out to have an element of error, which subsequent reflection and comparison may enable us to correct; just as many apparent perceptions through the organ of vision are found to be partially illusory and misleading: indeed the sequel will show that I hold this to be to an important extent the case with moral intuitions commonly so called.
The question as to the validity of moral intuitions being thus separated from the simple question `whether they actually exist', it becomes obvious that the latter can only be decided for each person by direct introspection or reflection. It must not therefore be supposed that its decision is a simple matter, introspection being always infallible: on the contrary, experience leads me to regard men as often liable to confound with moral intuitions other states or acts of mind essentially different from them,---blind impulses to certain kinds of action or vague sentiments of preference for them, or conclusions from rapid and half-unconscious processes of reasoning, or current opinions to which familiarity has given an illusory air of self-evidence. But any errors of this kind, due to careless or superficial reflection, can only be cured by more careful reflection. This may indeed be much aided by communication with other minds; it may also be aided, in a subordinate way, by an inquiry into the antecedents of the apparent intuition, which may suggest to the reflective mind sources of error to which a superficial view of it is liable. Still the question whether a certain judgment presents itself to the reflective mind as intuitively known cannot be decided by any inquiry into its antecedents or causes.
It is, however, still possible to hold that an inquiry into the Origin of moral intuitions must be decisive in determining their Validity. And in fact it has been often assumed, both by Intuitionists and their opponents, that if our moral faculty can be shown to be `derived' or `developed' out of other pre-existent elements of mind or consciousness, a reason is thereby given for distrusting it; while if, on the other hand, it can be shown to have existed in the human mind from its origin, its trustworthiness is thereby established. Either assumption appears to me devoid of foundation. On the one hand, I can see no ground for supposing that a faculty thus derived, is, as such, more liable to error than if its existence in the individual possessing it had been differently caused: to put it otherwise, I cannot see how the mere ascertainment that certain apparently self-evident judgments have been caused in known and determinate ways, can be in itself a valid ground for distrusting this class of apparent cognitions. I cannot even admit that those who affirm the truth of such judgments are bound to show in their causes a tendency to make them true: indeed the acceptance of any such onus probandi would seem to me to render the attainment of philosophical certitude impossible. For the premises of the required demonstration must consist of caused beliefs, which as having been caused will equally stand in need of being proved true, and so on ad infinitum: unless it be held that we can find among the premises of our reasonings certain apparently self-evident judgments which have bad no antecedent causes, and that these are therefore to be accepted as valid without proof. But such an assertion would be an extravagant paradox: and, if it be admitted that all beliefs are equally in the position of being effects of antecedent causes, it seems evident that this characteristic alone cannot serve to invalidate any of them.
I hold, therefore, that the onus probandi must be thrown the other way: those who dispute the validity of moral or other intuitions on the ground of their derivation must be required to show, not merely that they are the effects of certain causes, but that these causes are of a kind that tend to produce invalid beliefs. Now it is not, I conceive, possible to prove by any theory of the derivation of the moral faculty that the fundamental ethical conceptions `right' or `what ought to be done', `Good' or `what it is reasonable to desire and seek', are invalid, and that consequently all propositions of the form `X is right' or `good' are untrustworthy: for such ethical propositions, relating as they do to matter fundamentally different from that with which physical science or psychology deals, cannot be inconsistent with any physical or psychological conclusions. They can only be shown to involve error by being shown to contradict each other; and such a demonstration cannot lead us cogently to the sweeping conclusion that all are false. It may, however, be possible to prove that some ethical beliefs have been caused in such a way as to make it probable that they are wholly or partially erroneous: and it will hereafter be important to consider how far any Ethical intuitions, which we find ourselves disposed to accept as valid, are open to attack on such psychogonical grounds. At present I am only concerned to maintain that no general demonstration of the derivedness or developedness of our moral faculty can supply an adequate reason for distrusting it.
On the other hand, if we have been once led to distrust our moral faculty on other grounds---as (e.g.) from the want of clearness and consistency in the moral judgments of the same individual, and the discrepancies between the judgments of different individuals---it seems to me equally clear that our confidence in such judgments cannot properly be re-established by a demonstration of their `originality'. I see no reason to believe that the `original' element of our moral cognition can be ascertained; but if it could, I see no reason to hold that it would be especially free from error.