William of Champeaux
c.1070-1121. Medieval philosopher, theologian, and reforming bishop. He is best known for his controversy with Abelard on the question of universals. Reacting against Roscellinus* of Compiègne's Nominalist position of universals, William taught an extreme Realist doctrine. In 1100, while teaching at the cathedral school in Paris, Peter Abelard,* his pupil, attacked the position by illustrating the ludicrous logical results of this teaching. William left his post shortly afterward and retired to the Abbey of St.-Victor, where he modified his teachings and started a school of theology. He was consecrated bishop of Chãlons-sur-Marne in 1113 and was responsible for a reform of the clergy in his diocese. Few of his writings have survived, and his views on universals must largely be based on the descriptions of Abelard.