The Bowmar Professor in Humanistic Studies Emeritus atCornell University. A world authority on Western historyand canon law, he has published a dozen books includingFoundations of the Conciliar Theory: The Contributionsof the Medieval Canonists from Gratian to the GreatSchism; Origins of Papal Infallibility, 1150-1350: AStudy on the Concepts of Infallibility, Sovereignty andTradition in the Middle Ages; Medieval Poor Law: ASketch of Canonical Theory and Its Application inEngland; and Religion, Law and the Growth ofConstitutional Thought, 1150-1650. "