"Parens's scholarship is sound, persuasive, utterly interesting, and compelling. In many ways, this book may even be described as pathbreaking. The breadth of the author's reading in the history of philosophy, coupled with his deep understanding of the issues that have been raised over time, is extremely impressive. I also find his ability to integrate the secondary literature into his general exposition very helpful and masterful. Parens has a unique ability to formulate his concerns in terms of debates that have bothered scholars—and philosophers—through the ages and to contribute intelligently to the ongoing debate. Even those who find their theories skewed in this work cannot help but learn from what Parens has to say." — Charles E. Butterworth, University of Maryland, College Park"The topic of this book is not only significant to the history of medieval Islamic philosophy but to modern students of political philosophy, law, religion, and classics."—Terence Kleven, Queen's College