Gad Freudenthal is a senior research fellow at the Centre National de la Recherche Scientifique (CNRS) in France and in 2005 was visiting Horace W. Goldsmith Professor in Judaic Studies/History at Yale University. His main research interests are Greek philosophy of matter and the history of science in medieval Jewish communities. He is the author of Aristotle’s Theory of Material Substance: Form and Soul, Heat and Pneuma (1995) and the editor of Studies on Gersonides — A Fourteenth-Century Jewish Philosopher-Scientist (1992) and AIDS in Jewish Thought and Law (1998) and the co-editor of Torah et Science: Perspectives historiques et théoriques. Mélanges Charles Touati (2001). He is also the editor of the periodical Aleph: Historical Studies in Science and Judaism (published by the Hebrew University in Jerusalem).