[8] Beginning in the 1970s, he conducted research on Chinese cultural societies, studying unique phenomena such as yuanfen, filial piety, guanxi, and face.

His most influential books, recognized as essential reference works in Chinese psychology, are:[6] During the Martial Law era, Yang was a strong advocate for political freedom and democracy and was frequently critical of the Kuomintang government.

He and three other liberal scholars, Hu Fo, Li Hung-hsi [zh], and Chang Chung-tung, were considered the "Four Bandits" or "Four Poisonous Weeds" by the government.

After President Chiang Ching-kuo lifted the martial law in 1987, they established the political group Taipei Society (澄社, Chengshe) in 1989.

[9] Yang served as the founding president of the society,[2] which aimed to promote "freedom, fairness, diversity, and the equitable distribution of wealth".