Although Hasdai Crescas was a great leader of Spanish Jewry in the late fourteenth and early fifteenth centuries, he is known today chiefly for his philosophical work Sefer Or Adonai (The Book of the Light of the Lord, 1405-1410). In this work Crescas attempted to sound the death knell for the synthesis between Aristotelianism and Judaism achieved by such thinkers as Moses Maimonides and Gersonides. Yet unlike the Jewish opponents of Aristotelianism who attacked the philosophers from orthodox or Cabalistic standpoints, Crescas sought to undermine philosophically the Aristotelian worldview that pervades his predecessors' works. His trenchant critique of Aristotelian physics, especially the notions of time, place, infinity, and motion, shows affinities to the new physics developed at Paris by Nicholas Oresme and prefigured the treatment of these notions during the Renaissance.

It is possible to view Crescas's critique of Jewish Aristotelianism as a natural reaction against an "official...