Rabbi Levi ben Gershom (Ralbag, Gersonides; 1288-1344), one of medieval Judaism's most original thinkers, wrote about such diverse subjects as astronomy, mathematics, Bible commentary, philosophical theology, technical philosophy, logic, Halakhah, and even satire. In his view, however, all these subjects were united as part of the Torah. Influenced profoundly by Maimonides, Gersonides nevertheless exercised greater rigor than Maimonides in interpreting the Torah in light of contemporary science, was more conservative in his understanding of the nature of the Torah's commandments, and was more optimistic about the possibility of wide-spread philosophical enlightenment. Gersonides was a witness to several crucial historical events, such as the expulsion of French Jewry of 1306 and the Babylonian Captivity of the Papacy. Collaborating with prelates in his studies of astronomy and mathematics, he had an entree into the Papal court at Avignon. Kellner portrays Gersonides, revered among Jews as the author of a classic commentary on the latter books of the Bible, as a true renaissance man, whose view of Torah is vastly wider and more open than that held by many of those who treasure his memory. Professor Kellner is one of the more productive and creative scholars in medieval Jewish thought. Over the years he has published many important essays on various aspects of medieval Jewish philosophy, especially on Gersonides and Maimonides. These studies are fundamental readings for any student of medieval Jewish philosophy. This anthology of his writings is a most valuable contribution to our understanding of these two thinkers. Born and educated in the United States, Menachem Kellner (Ph.D., Washington University in St. Louis, 1973) has lived in Israel for the last 30 years. Author, editor, or translator of 16 books and over 100 scholarly articles, Kellners most recent book is Maimonides Confrontation with Mysticism (2006).Gersonides (1288-1344) was, in my view, the most lc+