John Locke's classic work An Essay Concerning Human Understanding laid the foundation of British empiricism and remains of enduring interest today. Rejecting doctrines of innate principles and ideas, Locke shows how all our ideas, even the most abstract and complex, are grounded in human experience-attained by sensation of external things or reflection upon our mental activities. A thorough examination of the communication of ideas through language and the convention of taking words as signs of ideas paves the way for his penetrating critique of the limitations of ideas and the extent of our knowledge of ourselves, the world, God and morals. This abridgement, based on P.H. Nidditch's acclaimed critical edition, retains in full all key passages, thus enabling Locke's arguments to be more clearly followed. The new introduction by Pauline Phemister provides valuable background on Locke's essay, illuminating its arguments and conclusions. The book also includes a chronological table of significant events, select bibliography, succinct explanatory notes, and an index-all of which supply additional historical information and aids to navigating the text.