Jeffrey F. Hamburger is Professor in the Department of History of Art and Architecture at Harvard University. He is author of these award-winning books: "The Visual and the Visionary "(1998), "Nuns as Artists: The Visual Culture of a Medieval Convent "(California, 1997), and "The Rothschild Canticles: Art and Mysticism in Flanders and the Rhineland circa 1300 "(1990). Among his honors are the John Nicholas Brown Prize of the Medieval Academy of America (1994), the Jacques Barzun Prize in Cultural History (1998), the Roland H. Bainton Prize (1998), and the Charles Rufus Morey Award in the Histo...