Yet in actual practice, what are these working hypotheses that work because they are compensating conceptions or doors in the panelling? No veracity without unrestrained voracity is interesting as a formula, but how verify it? Verification, or illustration, is now imperative. Illustration, however, is very difficult for a reason which the scientists now on trial must allow me to mention. The scientists know too much about the sciences, or at least of them, while I know too little. Still, as too much knowledge is often the source of obscurity, and so only a form of ignorance, my situation is not altogether hopeless. Thus, while it is true that the scientists are likely to insist, even in the face of a mind bound to preserve the unity of an indivisible universe in all the varied studies and conclusions of science, that physics is only physics and chemistry only chemistry and biology only biology and psychology only psychology, and while also all illustrations must come from the field of their special studies, and may therefore only set them more firmly in the wilful blindness of their specialism, still the principle of a conserving mind, or an eternally conserved truth or an indivisible reality, is a disturbing influence which they cannot evade. Then, too, I am forgetting and allowing them to forget a very important fact in scientific work to-day. In these [p.091] times the running together or merging of different sciences, as if through something of the nature of a chemical reaction, is a very familiar phenomenon. It is as familiar, although not so loudly heralded, as that of the railroads and industrial companies; and it has been taking place with such persistence and confidence as actually to suggest a natural affinity, each of the sciences involved having the rich experience of discovering itself already in the others. This fact, then, must make illustration less difficult, since, in a way that must appeal to the scientist as no merely theoretical considerations can, it proves or goes very far toward proving what is to be illustrated. Moreover, specific illustration is hardly necessary in the sphere of the different physical sciences, or again, in that of the social or the psychological sciences, for within each one of these groups the affinity but just now referred to has been very clearly exemplified, as in the interesting case of physics, chemistry, and mathematics, which nowadays are one science, not three, and which can be held apart only on methodological grounds, not metaphysically. Illustration, accordingly, appears, after all, to be needed only for the specialism that separates the physical and the psychical sciences.