born 1240, duchy of Brabant
died between 1281 and 1284, Orvieto, Tuscany
French philosopher.
He taught at the University of Paris and was a leader of the school of radical Aristotelianism. From 0441; 1260 he and others gave lectures on the works of Greek, Arabic, and medieval philosophers without regard for church teaching, which had blended Aristotelianism with the Christian faith. Some of his teachings were condemned in 1270 by the bishop of Paris, and in 1277 many more were condemned by the bishop. When summoned by the Inquisition (1276), he fled to Italy. Dante , in The Divine Comedy , put Siger in the Heaven of Light.