It holds that Life manifests in two aspects or forms, which are generally found by us in connection and co-operation with each other, but which are both, probably, an expression of some One Thing higher than either. These two aspects or forms, which together go to make up or produce that which we know as "Life," are known as (1) Substance or Matter; and (2) Mind. In this book the term "Substance" is used in preference to "Matter," owing to the fact that the term "Matter" has become closely identified with certain ideas of the Materialistic school of thought, and has generally been regarded by the public in the light of "dead matter," whereas this book holds that all Substance is Alive. The term "Mind" is used in the sense of "Mind, _as we know it_," rather than as "Mind, _as it is_"--or, as "The Cosmic Mind." In some places the term "Mind-principle" is used to convey the idea of "a portion of the Great Principle of Mind, of which that which we call 'Mind' is but a small and but partially expressed portion." These terms are explained and illustrated as we proceed. The aspect of "Energy or Force" is not treated as a separate aspect or form of Life, in this book, for the reason that it is regarded as merely a manifestation of Mind, as will appear as we proceed. We have much to say regarding Motion, but the writer has tried to explain and prove that, at the last, all Motion results from Mental Action, and that all Force and Energy is Vital-Mental Force and Energy. This book is not intended to run along metaphysical or theological lines--its field is different. And so, while it recognizes the importance of these branches of human thought, still, it finds that its own particular field is sufficient to engross its entire attention, for the moment, and, consequently the aforesaid subjects shall not be touched upon except incidentally, in connection with the subject matter of the book. This being the case, there will be no discussion of the "origin of Life"--the question of "creation"--the problems of theology and metaphysics--the riddle of the "Why and Wherefore" of Life and the Universe. The writer has his own opinions upon these questions, but feels that this is not the place in which to air the same. For the purposes of the book, he prefers to leave every reader to his own favorite views and conceptions regarding these great subjects, feeling that the views regarding Life, Mind, Motion and Substance, that are advanced in this book, may be accepted by any intelligent reader, without prejudice to his, or her, accepted religious or philosophical views. The writer sees that this something called "Life" exists--he finds it in evidence everywhere. And he sees it always in its aspects of Substance and Mind. And he feels justified in regarding "Life" as always existing in, and manifesting in these aspects--always in conjunction--at least, Life "as we know it."