Originally published in 1915, this book provides a detailed discussion of the relationship between metaphysics and material reality, arguing for a reconciliation between Christian theology and evolutionary theory. The main premise of the text is that there can be no strict division between the soul and the corporeal aspects of human life; the human being is viewed 'as a soul closely tied to a mechanism.' Nonetheless, this closely intertwined relationship is one in which the metaphysical aspect of existence is regarded as the fundamental driving force, and biological evolution is subordinated to spiritual progress. This book will be of value to anyone with an interest in theology, philosophy and theories of evolution.