The evidential scholar Tai Chen (1723-1777), who originally positioned himself in the tradition of Chu Hsi and the Sung Confucians, once wrote that "The discussion of 'principle' (li) , the 'Way' (tao) , the 'mind' (hsin) and 'human nature' (hsing) [by Sung advocates of `li-hsueh`] claims to be derived from the six classics and the writings of Confucius and Mencius. Yet this discussion of principle , the Way , the mind , and human nature is bound up with the doctrines of Lau-tzu and Buddhism". It was dissatisfaction with this body of scholarship that prompted Tai to write his `Yuan` shan , `Hsu` yen , Meng-tzu ssu-shu lu , and Meng-tzu tzu-i shu cheng. Nevertheless, because of the predominance in Tai's day of an evidential scholarship which emphasized the authority of Han interpretations, Tai did not make these writings available to the public. Even Tai Chen's closest student , Tuan `Yu-ts'ai` did not read the final editions of the `Hsu` yen and the Meng-tzu ssu-shu lu, or the Meng-tzu tzu-i shu cheng until after his teacher's death. For this reason , the dates of the composition of Yuan shan and the Meng-tzu tzu-i shu cheng have become an important subject of debate among scholars of Tai's thought. One crucial source for resolving this problem is Tai Chen's letter to P'eng Chi-ch'ing , a representative figure among lay Buddhists of the Ch'ien-lung period. This study, through analysis of Tai's lengthy letter , as well as of P'eng's "Letter to Tai Chen" (`Yu` Tai Tung-yuan shu) , explores the relationship between these two figures and their debate over Confucianism and Buddhism. In addition , this study examines the background for the approach to Han Learning (Han-hsueh) and Buddhism taken by the group known as the Kung-yang scholars, centered on the figures Kung Tzu-chen and Wei `Yuan`.
