This book is based on the author’s Psychology, now in preparation, which should logically have been published first. The standpoint of the latter is roughly and provisionally indicated in Chapter X, with which it is hoped any reader with philosophic interests will begin. This point of view is further set forth in the last part of Chapter XVI, and some of its implications appear in Chapter XII, which should follow. That, recognizing fully all that has hitherto been done in this direction, the genetic ideas of the soul which pervade this work are new in both matter and method, and that if true they mark an extension of evolution into the psychic field of the utmost importance, is the conviction of the author. Although most of even his ablest philosophical contemporaries, both American and European, must regard all such conceptions much as Agassiz did Darwinism, he believes that they open up the only possible line of advance for psychic studies, if they are ever to escape from their present dishonorable capitivity to epistemology, which has to-day all the aridity, unprogressiveness, and barrenness of Greek sophism and medieval scholasticism, without standing, as did these, in vital relations to the problems of their age.