An analysis of the course of Western intellectual history between A.D. 400 and 1400, this book is divided into two parts: the first surveys the comparative modes of thought and varying success of Byzantine, Latin-Christian and Muslim cultures, and the second takes readers from the 11th century revival of learning to the high Middle Ages and beyond, the period in which the vibrancy of Western intellectual culture enabled it to stamp its imprint well beyond the frontiers of Christendom. 24 illustrations.