In July 1952, he studied, then taught, at Renmin University of China, he served in several posts there, including instructor, professor, doctoral supervisor, and vice-president. He joined the Communist Party of China in 1955. In August 1989, he was appointed president of Peking University,[4] replacing Ding Shisun, who did not prevent students of Peking University from joining the Tiananmen Square protests.[5][6] When his term ended, he continued to serve as a professor, honorary director of the Council and president of Education Foundation at the university.