Cary J. Nederman is Associate Professor of Political Science at the University of Arizona. His most recent books include Three Tracts on Empire: Engelbert of Admont, Aeneas Silvius Piccolomini, and Juan de Torquemada (co-edited and co-translated with T. M. Izbicki) (1999) and Beyond the Persecuting Society: Religious Toleration Before the Enlightenment (co-edited with J. C. Laursen) (1998).

“This is a superb book that finds toleration where most deny that it exists—in the Middle Ages. Nederman not only finds toleration in this ‘monolithically intolerant’ period, but demonstrates the various sources of medieval theories of toleration: Abelard’s and Llull’s faith in interreligious dialogue, John of Salisbury’s skepticism, William of Rubruck’s view of a multi-religious empire, Marsiglio of Padua’s conception of the secular state, Nicholas of Cusa’s acceptance of ritual heterogeneity based on national difference, and Barolome de la Casas’s Ciceronian rationalism. By focusing on medieval theories of toleration, Worlds of Difference complements other works that begin their study of toleration from the Renaissance or beyond. Nederman’s book will be required reading for all who want a complete view of the history of toleration. It is bound to be the authoritative work on medieval ideas of toleration for a long time to come.”—Gary Remer, Tulane University