Professor Bergson's theory of dreaming here set forth in untechnical language, fits into a particular niche in his general system of philosophy as well as does his little book on _Laughter_. With the main features of his philosophy the English-reading public is better acquainted than with any other contemporary system, for his books have sold even more rapidly here than in France. When Professor Bergson visited the United States two years ago the lecture-rooms of Columbia University, like those of the College de France, were packed to the doors and the effect of his message was enhanced by his eloquence of delivery and charm of personality. The pragmatic character of his philosophy appeals to the genius of the American people as is shown by the influence of the teaching of William James and John Dewey, whose point of view in this respect resembles Bergson's. During the present generation chemistry and biology have passed from the descriptive to the creative stage. Man is becoming the overlord of the mineral, vegetable and animal kingdoms. He is learning to make gems and perfumes, drugs and foods, to suit his tastes, instead of depending upon the chance bounty of nature. He is beginning consciously to adapt means to ends and to plan for the future even in the field of politics. He has opened up the atom and finds in it a microcosm more complex than the solar system. He beholds the elements melting with fervent heat and he turns their rays to the healing of his sores. He drives the lightning through the air and with the product feeds his crops. He makes the desert to blossom as the rose and out of the sea he draws forth dry land. He treats the earth as his habitation, remodeling it in accordance with his ever-varying needs and increasing ambitions. This modern man, planning, contriving and making, finds Paley's watch as little to his mind as Lucretius's blind flow of atoms. A universe wound up once for all and doing nothing thereafter but mark time is as incomprehensible to him as a universe that never had a mind of its own and knows no difference between past and future. The idea of eternal recurrence does not frighten him as it did Nietzsche, for he feels it to be impossible. The mechanistic interpretation of natural phenomena developed during the last century he accepts at its full value, and would extend experimentally as far as it will go, for he finds it not invalid but inadequate. To minds of this temperament it is no wonder that Bergson's _Creative Evolution_ came with the force of an inspiration. Men felt themselves akin to this upward impulse, this _elan vital_, which, struggling throughout the ages with the intractableness of inert matter, yet finally in some way or other forces it to its will, and ever strives toward the increase of vitality, mentality, personality.