Originally published: London : George Allen & Unwin, 1927.

Includes bibliographical references and index.

Philosophic doubts -- Man from without -- Man and his environment -- The process of learning in animals and infants -- Language -- Perception objectively regarded -- Memory objectively regarded -- Inference as a habit -- Knowledge behaviouristically considered -- The physical world -- The structure of the atom -- Relativity -- Causal laws in physics -- Physics and perception -- Physical and perceptual space -- Perception and physical causal laws -- The nature of our knowledge of physics -- Man from within -- Self-observation -- Images -- Imagination and memory -- The introspective analysis of perception -- Consciousness? -- Emotion, desire, and will -- Ethics -- The universe -- Some great philosophies of the past -- Truth and falsehood -- The validity of inference -- Events, matter, and mind -- Man's place in the universe.