 James tells us that he will follow the psychological method of introspection in The Principles, which he defines as “the looking into our own minds and reporting what we there discover” (PP 185). In fact he takes a number of methodological approaches in the book. Early on, he includes chapters on “The Functions of the Brain” and “On Some General Conditions of Brain Activity” that reflect his years as a lecturer in anatomy and physiology at Harvard, and he argues for the reductive and materialist thesis that habit is “at bottom a physical principle” (PP 110). As the book moves along, he involves himself in discussions with philosophers—for example with Hume and Kant in his hundred-page chapter on the self, and he finds himself making metaphysical claims that anticipate his later pragmatism, as when he writes: “There is no property ABSOLUTELY essential to any one thing. The same property which figures as the essence of a thing on one occasion becomes a very inessential feature on the other” (PP 959).