This page needs to be proofread.

212 B. B. HALDANE : objects ". Here the psychophysical standpoint is of much value. Whether by what is physical we mean, as Prof. Munsterberg thinks, what is " a possible object for every subject," as distinguished from the psychical occurrence which is possible object for " one subject only," is a question to which every one might not give the answer that Prof. Munsterberg gives. Is there any such division of the two kinds of experience? It is true that the contents of my consciousness cannot be directly apprehended by any one else, but this truth is apparently not confined to the im- pressions of what is called inner sense. My visual im- pression of a locked gate is just as much within my own consciousness as is my impression of annoyance at the prospective trouble of having to climb over it. The real medium of communication does not appear to be reduction to a common external experience for no experience of mine whether external or internal, can really be shared by any other but reduction to symbols which indicate general relations that intelligence can grasp and express. If I describe the gate as white, and of a certain height and in a certain wall, others will be able to classify their experience as, not identical with, but similar to mine. It is here that the categories and relations of quantity, and the symbols of language which represent them, become of immense value ; and it is probably in the main through these that we con- struct that most rooted fiction of common sense, the fafon de parler of a common experience identical for a plurality of subjects. But this is not the place to follow out this problem, for even if we do not accept Prof. Miinsterberg's version of the answer it does not affect the general drift of his reasoning. Passing from physiology to education and art, which form the topics of the next two chapters, the author attacks those who think that the abstract methods of psychology can throw much light on subject matter cognisable only under wholly different categories. It would occupy too much space to quote the passages, beginning at p. 128, in which Prof. Mnnsterberg pours scorn on the notion that the teacher ought to be a psychologist. Child psychology may be and often is useful in other sciences, never in the science of teaching as such. "Certainly the teacher ought to study children and men in general, but with the strictly anti- psychological point of view ; he ought to acknowledge them as indissoluble unities, as centres of free will, the functions of which are not causally but teleologically connected by