Book excerpt: A one-voume reference to the history of ideas that is a compendium of everything that humankind has thought, invented, created, considered, and perfected from the beginning of civilization into the twenty-first century. Massive in its scope, and yet totally accessible, A HISTORY OF KNOWLEDGE covers not only all the great theories and discoveries of the human race, but also explores the social conditions, political climates, and individual men and women of genius that brought ideas to fruition throughout history. Crystal clear and concise...Explains how humankind got to know what it knows. Clifton Fadiman Selected by the Book-of-the-Month Club and the History Book Club