Nature, meanwhile, that part of the universe which is not consciously guided, has become within a century our favorite field of scientific study. The very word science is popularly appropriated to naturalistic investigation. Of course this is a perversion. Originally it was believed that the proper study of mankind was man. And probably we should all still acknowledge that the study of personal structure is as truly science as study of the structure of physical objects. Yet so powerfully is the tide setting toward reverence for the unconscious and the sub-conscious that science, our word for knowledge, has lost its universality and has taken on an almost exclusively physical character. Perhaps there was only one farther step possible. Philosophy itself, the study of mind, might be regarded as a study of the unconscious. And this step has been taken. Books now bear the paradoxical title "Philosophy of the Unconscious," and investigation of the sub- conscious processes is perhaps the most distinctive trait of philosophy to-day. More and more it is believed that we cannot adequately explore a person without probing beneath consciousness. The blind processes can no longer be ruled out. Nature and spirit cannot be parted as our fathers supposed they might. Probably Kant is the last great scholar who will ever try to hold that distinction firm, and he is hardly successful. In spite of his vigorous antitheses, hints of covert connection between the opposed forces are not absent. Indeed, if the two are so widely parted as his usual language asserts, it is hard to see how his ethics can have mundane worth. Curiously enough too, at the very time when Kant was reviving this ancient distinction, and offering it as the solid basis of personal and social life, the opposite belief received its most clamorous announcement, resounding through the civilized world in the teachings of Rousseau. Rousseau warns us that the conscious constructions of man are full of artifice and deceit, and lead to corruption and pain. Conscious guidance should, consequently, be banished, and man should return to the peace, the ease, and the certainty of nature. V Now I do not think it is worth while to blame or praise a movement so vast as this. If it is folly to draw an indictment against a nation, it is greater folly to indict all modern civilization. We must not say that philosophy and the fine arts took a wrong turn at the Renaissance,--at least it is useless to call on them now to turn back. The world seldom turns back. It absorbs, it re-creates, it brings new significance into the older thought. All progress, Goethe tells us, is spiral,--coming out at the place where it was before, but higher up. No, we cannot wisely blame or praise, but we may patiently study and understand. That is what I am attempting to do here. The movement described is no negligible accident of our time. It is world-wide, and shows progress steadily in a single direction.