c. 1215-c. 1286

French scholar who translated numerous works by ancient Greek scientists, in many cases making the writings of thinkers such as Aristotle (384-322 B.C.) available for the first time to the scholars of medieval Western Europe. A member of the Dominican order, William was acquainted with such leading figures of the time as Thomas Aquinas (c. 1225-1274) and Witelo (c. 1230-1275), and served as consultant to Pope Gregory X during the Council of Lyons in 1274. In addition to Aristotle, he translated commentaries on the latter, as well as works by Hippocrates (c. 460-c. 377 B.C.), Ptolemy (c. 100-170), and the Neoplatonist Proclus (c. 410-485).