Chapter XVII · (continued 2)

And if this is true of philology, assuredly it is no less true of psychology. For “the development of speech is only a copy of that chain of processes, which began with the dawn of [human] consciousness, and eventually ends in the construction of the most abstract idea.”[346] Unless, therefore, it can be shown that my distinction between ideation as receptual and conceptual is invalid, I know not how my opponents are to meet the results of the foregoing analysis. Yet, if this distinction should be denied, not only would they require to construct the science of psychology anew; they would place themselves in the curious position of repudiating the very distinction on which their whole argument is founded. For I have everywhere been careful to place it beyond question that what I have called receptual ideation, in all its degrees, is identical with that which is recognized by my opponents as non-conceptual; and as carefully have I everywhere shown that with them I fully recognize the psychological difference between this order of ideation and that which is conceptual. The only point in dispute, therefore, is as to the possibility of a natural transition from the one to the other. It is for them to show the impossibility. This they have hitherto most conspicuously failed to do. On the other hand, I now claim to have established the possibility beyond the reach of a reasonable question. For I claim to have shown that the probability of such a transition having previously occurred in the race, as it now occurs in every individual, is a probability that has been raised tower-like by the accumulated knowledge of the nineteenth century. Or, to vary the metaphor, this probability has been as a torrent, gaining in strength and volume as it is successively fed by facts and principles poured into it by the advance of many sciences.

Of course it is always easy to withhold assent from a probability, however strong: “My belief,” it may be said, “is not to be wooed; it shall only be compelled.” Indeed, a man may even pride himself on the severity of his requirements in this respect; and in popular writings we often find it taken for granted that any scientific doctrine is then only entitled to be regarded as scientific when it has been demonstrated. But in science, as in other things, belief ought to be proportionate to evidence; and although for this very reason we should ever strive for the attainment of better evidence, scientific caution of such a kind must not be confused with a merely ignorant demand for impossible evidence. Actually to demonstrate the transition from non-conceptual to conceptual ideation in the race, as it is every day demonstrated in the individual, would plainly require the impossible condition that conceptual thought should have observed its own origin. To demand any demonstrative proof of the transition in the race would therefore be antecedently absurd. But if, as Bishop Butler says, “probability is the very guide of life,” assuredly no less is it the very guide of science; and here, I submit, we are in the presence of a probability so irresistible that to withhold from it the embrace of conviction would be no longer indicative of scientific caution, but of scientific incapacity. For if, as I am assuming, we already accept the theory of evolution as applicable throughout the length and breadth of the realm organic, it appears to me that we have positively better reasons for accepting it as applicable to the length and breadth of the realm mental. In other words, looking to all that has now been said, I cannot help feeling that there is actually better evidence of a psychological transition from the brute to the man, than there is of a morphological transition from one organic form to another, in any of the still numerous instances where the intermediate links do not happen to have been preserved. Thus, for example, in my opinion an evolutionist of to-day who seeks to constitute the human mind a great exception to the otherwise uniform principle of genetic continuity, has an even more hopeless case than he would have were he to argue that a similar exception ought to be made with regard to the structure of the worm-like creature Balanoglossus.

If this comparison should appear to betray any extravagant estimate on my part of the cogency of the evidence which has thus far been presented, I will now in conclusion ask it to be remembered that my case is not yet concluded. For hitherto I have almost entirely abstained from considering the mental condition of savages. The reason why this important branch of my subject has not been touched is because I reserve it for the next instalment of my work. But when we leave the groundwork of psychological principles on which up to this point we have been engaged, and advance to the wider field of anthropological research in general, we shall find much additional evidence of a more concrete kind, which almost uniformly tends to substantiate the conclusions already gained. The corroboration thus afforded is indeed, to my thinking, superfluous; and, therefore, will not be adduced in this connection. Nevertheless, while tracing the principles of mental evolution from the lowest levels which are actually occupied by existing man, we shall find that no small light is incidentally thrown upon the demonstrably still more primitive intelligence of pre-historic man. Thus shall we find that we are led back by continuous stages to a state of still human ideation, which brings us into contact almost painfully close with that of the higher apes. This, indeed, is a side of the general question which my opponents are prone to ignore—just as they ignore the parallel side which has to do with the psychogenesis of a child. And, of course, when they thus ignore both the child and the savage, so as directly to contrast the adult psychology of civilized man with that of the lower animals, it is easy to show an enormous difference. But where the question is as to whether this is a difference of degree or of kind, the absurdity of disregarding the intermediate phases which present themselves to actual observation is surely too obvious for comment. At all events I think it may be safely promised, that when we come to consider the case of savages, and through them the case of pre-historic man, we shall find that, in the great interval which lies between such grades of mental evolution and our own, we are brought far on the way towards bridging the psychological distance which separates the gorilla from the gentleman.