Wu Ch'eng (1249-333) was the most innovative Confucian scholarteacher during the Mongol epoch in China, and his thought is a bridge between thinkers of the Sung und Ming eras. Having experienced the Mongol takeover in his thirties and the abrogation of the examination system, which blocked the traditional route to an official career, Wu was at first associated with Sung loyalists and did not serve the Yüan rulers until he was over sixty (in the National College and the Hanlin Academy). Even then, his affinities for Taoism and individualistic strains in Confucian thought set him at odds with those who reestablished the examination system in the early fourteenth century. He was also one of the first scholars to question the legitimacy of the conquest dynasties. Wu pursued a scholarly vision that bore fruit in his searching classical commentaries, educational policies, and philosophical essays stressing intellectual enlightenment. This study of Wu's life and career examines his flirtations with official service, his disagreements with the educational establishment at the capital and locally, and how these experiences shaped his outlook.