Just such synthetic harmonization, and not at all a stubborn ignorance of the other side or a compromise with cheap concessions, was the aim of the period from Kant to Emerson. It is merely the naturalistic period which ignores its idealistic counterpart, which delights in its one-sidedness, which is afraid of harmony because it is suspicious of demands for concessions. It is naturalism only which thinks that mankind can walk on one leg. If we ask where such harmonization can be found, where the great Idealists of the beginning of the last century have sought it, and where our modern philosophy is seeking it again, well aware that by the progress of science in the mean time the difficulties have been multiplied, the logical responsibilities have become gigantic, we cannot do more here than to point out the direction; we cannot go the way. And it is clear, of course, too, that such an answer has its individual shape, and that no one can promise to give a bird's-eye view of the marching movement while he is himself marching among his comrades. But the individual differences are non-essential. The one great tendency, the Emersonian spirit, if it is rightly understood, is common to them all. What has modern philosophy all over the world to say about that threefold claim concerning Nature, Freedom, and Oversoul? What has it to say when natural science has fully said its say and had its fair hearing, and has been approved as sound and welcome? A philosopher might answer, perhaps, as follows: You Positivists have done wonderfully with your microscopes and your telescopes, with your chronoscopes and spectroscopes; you have measured and weighed and analyzed and described, and finally explained the whole world which you perceive, and there is nothing in space and time and causality which can escape your search. But did not all that work of yours involve certain presuppositions which you had accepted and which it was not your business to look on critically, but which, nevertheless, may be open to enquiry? Your first claims granted, all may follow; but how is it with the first claims? You examine all that is in space and time, but what are space and time? You examine the material substances and the contents of consciousness, but what is consciousness, and what is matter? You seek the special applications of causality, but what is causality? Well, you reply, you give the facts just as you find them; but do you do that really? And what do you mean by saying that you find the facts? Let us look, at least for a moment, at the very simplest facts with which your work begins. You say there are physical objects made up of atoms, and you describe them as a physicist; and there are mental ideas in consciousness made up of sensations, and you describe them as a psychologist; and both, you say, you are finding. But what does it mean, that you find the physical object outside there and the mental idea of the object inside in you; is that really a statement