Fung Yu-lan's philosophical works, which developed under the influence of American pragmatism and Neo-Realism, as well as Confucianism and Marxism, show a marked transition from traditional interpretations to radical Maoist thinking. After receiving his B.A. from Beijing University, Fung went to Columbia University to complete his doctorate in philosophy. Still sympathetic to Confucianism, he returned to China in the late 1920s and set to work applying his newly learned pragmatic methods to the study of classical Chinese philosophy. The development of this comparative East-West perspective can be seen in both his Philosophy of Life and his two-volume A History of Chinese Philosophy (1931, 1934). In attempting to overturn many traditional interpretations, he soon earned a reputation for himself, not only in China, but also in the West. By the late 1930s, Fung had started to formulate his own philosophical system---a rational formalism that reinterpreted the apparently ontological categories of Neo-Confucianism (such as dao, li, and qi, also romanized as tao, li, and ch'i ) into logical functions. Of his works at this time, New Li Hsueh (The New Rational Philosophy) was his most important and famous expression of Neo-Confucianism in light of modern philosophy. With the Communist Revolution, Fung's ideas came under attack as being overly idealistic. This led to the rethinking of his former historical and logical positions more in light of dialectical materialism. Fung eventually became a supporter of Mao Tse-tung's anti-Confucian campaign during the 1970s and served as intellectual consultant to Mao's wife, Chiang Ch-ing. Nevertheless, Fung never quite fit the paradigm of the Maoist philosopher, and until his death his philosophy periodically underwent official criticism as being overly "abstract" and "idealistic." His "philosophical career" ended when Chiang's group fell from power shortly after Mao's death.