This is an enlarged, revised edition of the Paul Carus lecturers which John Dewey delivered in 1925. It covers Dewey's basic formulation of the problem of knowledge, with both a full discussion of theories and resolutions propounded by other systems, and a detailing of Dewey's own concepts upon the relationship of the external world, the minds, and knowledge. Starting with a thorough examination of philosophical method, Dewey examines the interrelationship of experience and nature, and upon the basis of empirical naturalism analyzes experience, the formulation of law, the role of language and social factors in knowledge, the nature of mind, and the final interrelation of mind and matter. Dewey, as in his other mature philosophy, attempts to replace the traditional separation of nature and experience with the idea of continuity, using the traditional separation of nature and experience with the idea of continuity, using the concept of language as the bridge. Dewey's treatment of central problems in philosophy and philosophy of science is profound, yet extremely easy to follow. His range of subject matter is very wide, from the anthropology of Malinowski to gravity, evolution, and the role of art, and his insights are clear and valuable. Scientists, philosophers of science, philosophers, and students of American history of thought will all find this one of the most profitable works by a great 20th-century thinker.