problems which need philosophy, and to-day philosophers, with good or bad philosophy, are at work everywhere. The physicists, the chemists and the biologists, the astronomers and the mathematicians, the psychologists and the sociologists, the historians and the economists, the linguists and the jurists, all are to-day busily engaged in philosophical enquiries, in enquiries into the conditions of their knowledge, into the presuppositions and methods of their sciences, into their ultimate principles and conceptions; in short, without a word of sudden command, the front has changed its direction. We are moving again towards philosophy, towards Idealism, towards Emerson. Does all this mean that we are to forget the achievements of natural science, and ignore the results of empirical labor, of labor which has given us an invincible mastery of stubborn nature and an undreamed-of power to calculate all processes of the physical and of the psychical world? No sane man can entertain such a notion. Yes, such ideas would contradict the laws which have controlled the alternation of Idealism and Positivism through the ages of the past. Whenever Positivism returned, it always showed a new face, and the teaching of the intervening period of Idealism was never lost. The naturalism of the middle of the nineteenth century was not at all identical with the naturalism of the middle of the eighteenth; and so Idealism too, as often as it returned to mankind after periods of neglect and contempt, had every time gained in meaning, had every time found increased responsibilities, had every time to do justice to the new problems which the preceding period of Positivism had raised. If Idealism to-day wants to gain new strength, nothing must be lost of all that the last fifty years have brought us, no step must be taken backward, the careful scientific work of the specialists must be encouraged and strengthened, and yet the totality of this work must be brought under new aspects which allow a higher synthesis; yes, a higher synthesis is the problem of the philosopher of to-day. He does not want to be ignorant of natural science and simply to substitute idealistic demands in the place of solid, substantial facts; and he should feel ashamed of the foul compromise with which half-thinkers are easily satisfied, a compromise which allows science its own way till it comes over the boundaries of human emotions, a compromise which accepts rigid causality but pierces little holes in the causal world, making little exceptions here and there that human freedom may be saved in the midst of a world-machinery; a compromise which accepts the social origin of ideals, but claims a mystic knowledge that just our own private pattern will remain in fashion for eternity. No philosophy can live by compromises. If natural science is to be accepted and Idealism is to hold its own, they must be combined, they must form a synthesis in which the one no longer contradicts the other.