Finally, I have in Part III sought to present the tradition of philosophy in the form of general types. My purpose in undertaking so difficult a task is to acquaint the reader with philosophy in the concrete; to show how certain underlying principles may determine the whole circle of philosophical ideas, and give them unity and distinctive flavor. Part II offers a general classification of philosophical problems and conceptions independently of any special point of view. But I have in Part III sought to emphasize the point of view, or the internal consistency that makes a _system of philosophy_ out of certain answers to the special problems of philosophy. In such a division into types, lines are of necessity drawn too sharply. There will be many historical philosophies that refuse to fit, and many possibilities unprovided for. I must leave it to the individual reader to overcome this abstractness through his own reflection upon the intermediate and variant stand-points. Although the order is on the whole that of progressive complexity, I have sought to treat each chapter with independence enough to make it possible for it to be read separately; and I have provided a carefully selected bibliography in the hope that this book may serve as a stimulus and guide to the reading of other books. The earlier chapters have already appeared as articles: Chapter I in the _International Journal of Ethics_, Vol. XIII, No. 4; Chapter II in the _Philosophical Review_, Vol. XI, No. 6; Chapter III in the _Monist_, Vol. XIV, No. 5; Chapter IV in the _International Journal of Ethics_, Vol. XV, No. 1; and some paragraphs of Chapter V in the _Journal of Philosophy, Psychology, and Scientific Methods_, Vol. I, No. 7. I am indebted to the editors of these periodicals for permission to reprint with minor changes. In the writing of this, my first book, I have been often reminded that a higher critic, skilled in the study of internal evidence, could probably trace all of its ideas to suggestions that have come to me from my teachers and colleagues of the Department of Philosophy in Harvard University. I have unscrupulously forgotten what of their definite ideas I have adapted to my own use, but not that I received from them the major portion of my original philosophical capital. I am especially indebted to Professor William James for the inspiration and resources which I have received from his instruction and personal friendship. RALPH BARTON PERRY. CAMBRIDGE, March, 1905. FOOTNOTES: [vii:A] Edw. Caird: _Literature and Philosophy_, Vol. I, p. 207. TABLE OF CONTENTS PART I APPROACH TO THE PROBLEM OF PHILOSOPHY PAGE CHAPTER I. THE PRACTICAL MAN AND THE PHILOSOPHER 3