This book focuses on two primary concerns, language and philosophical thinking. The first part of the book examines the ways that language, particularly the English language, shapes and channels our thoughts. The second part considers the three basic processes in concept formation: abstracting, imagining and generalizing. Lastly, the rational process itself is examined, looking at definition, rational inquiry and philosophical system building. First published in 1967, this edition is a reprint of the 1972 enlarged edition published by University of New Mexico Press.