"Just in the same way that I believe the intuition of space, possessed by any living individual, to have arisen from organised and consolidated experiences of all antecedent individuals who bequeathed to him their slowly-developed nervous organisations—just as I believe that this intuition, requiring only to be made definite and complete by personal experiences, has practically become a form of thought, apparently quite independent of experience; so do I believe that the experiences of utility, organised and consolidated through all past generations of the human race, have been producing corresponding nervous modifications, which, by continued transmission and accumulation have become in us certain faculties of moral intuition—certain emotions responding to right and wrong conduct, which have no apparent basis in the individual experiences of utility."

In short, Spencer maintained that intellectual and moral intuitions had arisen from gradually organised and inherited experience. "What the transcendentalist called a priori principles the evolutionist regards as a priori indeed to the individual, but a posteriori to the race; that is as race experiences which in the individual appear as intuitions."[16]

[16] W. H. Hudson, Introduction to the Philosophy of Herbert Spencer.

This was an ingenious eirenicon, but it does not seem to satisfy all the philosophers, those namely who feel that intuitions—both intellectual and moral—have a validity, universality, and compelling necessity which cannot be accounted for if they are simply the outcome of race-experience. The only alternative seems to be to say that their validity depends on the nature of mind itself, or, what comes to the same thing, because they are in harmony with the spiritual principle in nature.

Nor are the biologists quite satisfied with Spencer's reconciliation, between empiricism and apriorism, for, in the form he gave it, there is the tacit assumption that results of experience are as such transmissible. But this is biologically a hazardous assumption. The only alternative would be to suppose that the advance to rational intuitions came about by the selection of variations towards that type of mental constitution which rational and moral intuitions express—a probably very slow process which would be sheltered by the individual moulding himself to the social heritage in which many results of experience are registered and entailed independently of any germ-plasm. It is possible that there has been an underestimate of the extent to which what are regarded as intuitions are sustained by tradition in the widest sense, and an underestimate of the extent to which they are individually acquired by each successive generation.

When we speak of either instincts or intuitions arising by the selection of variations, we need not think of such wonderful results as originating in fortuitous mental sports; we are quite entitled to think of definiteness in mental (at the same time neural) variation as in bodily variation; we are quite entitled to think of mental (at the same time neural) 'mutations' as well as bodily 'mutations'; we do not require to burden natural selection with more than the pruning off of irrationalities, instabilities, disharmonies, and imbecilities. Thus even biologically we may admit that the validity of intuitions depends on the nature of mind itself, socially confirmed from age to age.

Test of Truth.—Spencer took great stock in "intuitions," especially in his First Principles, and yet he believed in their empirical origin; and this leads us to ask what his test of truth was. It may be summed up in the phrase "the inconceivability of the opposite." After a curiously self-contradictory attempt to show by reasoning that "a certainty greater than that which any reasoning can yield has to be recognised at the outset of all reasoning," he states the "universal postulate": "The inconceivableness of its negation is that which shows a cognition to possess the highest rank—is the criterion by which its insurpassable validity is known."

He admitted, however, that there were limitations to the utility of this test of truth. "That some propositions have been wrongly accepted as true, because their negations were supposed inconceivable when they were not, does not disprove the validity of the test, for these reasons: (1) That they were complex propositions, not to be established by a test applicable only to propositions no further decomposable; (2) that this test, in common with any test, is liable to yield untrue results, either from incapacity or from carelessness in those who use it." In regard to which Prof. Sidgwick says:[17] "These two qualifications surely reduce very much the practical value of the criterion. For how are we to proceed if philosophers disagree about the application of the criteria? How are we to test 'undecomposability'? For notions which on first reflection appear to us simple are so often found on further reflective analysis to be composite. Which conclusion, then, are we to trust, the earlier or the later? This seems to me a serious dilemma for Mr Spencer; whichever way he answers he is in a difficulty."

It would seem then that Spencer did not get much further than others who have tried to answer the question: What is the test of truth? Nor for our part can we supply the deficiency. It is probably more profitable, as Sidgwick says, "to turn from infallible criteria to methods of verification, from the search after an absolute test of truth to the humbler task of devising modes of excluding error." "These verifications are based on experience of the ways in which the human mind has actually been convinced of error, and been led to discard it; i.e., three modes of conflict, conflict between a judgment first formed, and the view of this judgment taken by the same mind on subsequent reconsideration; conflict between two different judgments, or the implications of two partially different judgments formed by the same mind under different conditions; and finally, conflict between the judgments of different minds." In other words, what is true for us is that which survives these conflicts, but the conflict is unceasing.