The man we call Averroes was one of the great thinkers of the Muslim world during the Middle Ages. An accomplished physician and judge, Averroes is most renowned for writing comprehensive commentaries on Aristotle, ranging from short paraphrases of the great Greek philosopher's words to lengthy, line-by-line analyses approachable by only the most learned scholars. In time, Averroes's commentaries introduced Europe, which had been plunged into the...