knew exactly where to point his great telescope, and, as we all know, it pointed to Neptune.
It was the same with geology. Sir Charles Lyell substituted for the unimaginable cataclysms of the older geologists the slow and simple operations of Nature's present forces. It was his work which changed geology from a wild dream into an accurate science, and to-day we hold this principle of causation as the check and test of all geological speculations.
The science of chemistry was born when the principle of the conservation of matter became established, and men stood face to face with the necessary relation between cause and effect; when they realized their own inability to bring matter out of nothingness, or to make it pass into nothingness again. Similarly, physics, as a science, came only with the recognition of the principles of the conservation of energy and the correlation of forces. It is difficult for us, standing on the vantage ground of the present, to realize into what an abyss we should suddenly plunge if we lost sight for one moment of these gains and passed into a world of thought in which energy came and went and matter appeared and disappeared. It would practically be a world of insanities.
Almost in our own generation we have seen the birth of the science of biology, and we all remember very vividly the bitter pain of its birth. As a branch of study, it has existed from the very earliest days when man first began to observe animated Nature; but it remained a body of isolated facts until the work of Darwin and Wallace established the causal relations involved in evolution, and suggested the mode by which this process of unfolding had been brought about.
It would be very easy to enlarge these illustrations in what we call the "natural" sciences, but it is hardly necessary. The point is probably established.
In those branches of inquiry which have to do with human rather than with purely physical activities, we shall find precisely the same thing; but in this case their history is so complex that the recognition of the principle of causation, and its application to human affairs, have been correspondingly slower. Even now it is far from complete. Nevertheless, in this study of the human spirit, we have all along been blindly trying to establish the principle of cause and effect. In the half-science which has grown out of this attempt, the failure has come, not from a wrong end in mind—and this is to be particularly noted but—rather from the establishment of fictitious causal relationships. In the complex operations of the human spirit we have observed definite results; we have sought for causes; we have not been wise enough to find them; but we have found something which we mistook for causes, and so we have built up a system founded on false re-
