The history of the evolution of life, incomplete as it is, already reveals to us how the intellect has been formed, by an uninterrupted progress, along a line which ascends though the vertebrate series up to man. Found in this present work are chapters relative to: evolution of life, mechanism and teleology; divergent directions of the evolution of life, torpor, intelligence, instinct; on the meaning of life, the order of nature and the form of intelligence; cinematographical mechanism of thought and the mechanistic illusion, a glance at the history of systems, real becoming and false evolutionism.