In the second part of this essay material from two papers published in the _Journal of Philosophy, Psychology and Scientific Methods_ has been laid under contribution, and also from my doctor’s thesis. Much of this material was written in 1909, since which time a number of views which some of mine resemble more or less have been published. It has not seemed to me necessary always to note these agreements of thought arrived at independently by myself and others. I have reported a part of the brilliant critique of Bergson’s doctrine of freedom by Monsieur Gustave Belot. This expresses with elegance and force much of my own reaction to the doctrine. Indebtedness to Belot and other authors is acknowledged throughout the essay. Except possibly Professor Bergson himself, there is no one who has influenced my thinking so much as Professor Ralph Barton Perry, my teacher who introduced me to Bergson’s philosophy. Professor Perry’s writings are full of finished renderings of less articulate convictions of my own; and, though I have often referred to and quoted from his work explicitly, his instruction and stimulus have had so much to do with the history of my thinking that I could never say just what I owe him, but only that I owe him much. Professor Bergson has permitted me to translate from a private letter some comments of his on certain of my criticisms. Professor Edmund H. Hollands has given the first two parts a careful reading, in the manuscript, and his able criticisms and suggestions, mainly concerning the matter itself, have been of great benefit. I am no less obliged, for help in improving the literary form, to Professor S. L. Whitcomb, whose critical ability has been patiently applied to a careful revision, page by page, of the whole manuscript. I have tried, in the third part, to justify explicitly the great and unique value which I attach to Professor Bergson’s work, antagonistic though my own convictions are to his results. And, besides this aim, it has seemed to me interesting and instructive, in view of the very considerable literature which has grown up about Bergson’s philosophy, to bring together in a comparative view the judgments of a number of his exponents. For literature by and about Bergson, the reader is referred to the exhaustive bibliography prepared last year by the Columbia University Press under the direction of Miss Isadore G. Mudge, the Reference Librarian. “The bibliography includes 90 books and articles by Professor Bergson (including translations of his works) and 417 books and articles about him. These 417 items represent 11 different languages divided as follows:--French 170, English 159, German 40, Italian 19, Polish 5, Dutch 3, Spanish 3, Roumanian 2, Swedish 2, Hungarian 1.” This work is invaluable to the student of Bergson. It is incomparably the fullest Bergson bibliography extant. ARTHUR MITCHELL. University of Kansas, January, 1914. PART ONE