Mary Carruthers is Professor Emeritus of English at New York University. She is author of The Book of Memory: A Study of Memory in Medieval Culture and The Craft of Thought: Rhetoric, Meditation, and the Making of Images, 400-1200. Jan M. Ziolkowski is Arthur Kingsley Porter Professor of Medieval Latin at Harvard University and editor of Obscenity: Social Control and Artistic Creation in the European Middle Ages.