Zheng Chen is an ancient author about whom very little is known. Publicly available sources contain no clear record of his place of origin, birth and death dates, or official career. What can be confirmed is that he wrote the work Yanji, of which a version titled Yanji (Unannotated Edition) also survives, and that two of his works are held in the collection. Judging from the extant works, Zheng Chen's writing touches on calligraphy theory and literary appreciation, discussing the origins and development of calligraphy, the aims of brush technique, and evaluations of earlier calligraphers' works, showing the speculative character of traditional literati criticism. His prose is concise and stresses underlying principles, and he is adept at advancing personal judgments while tracing the history of calligraphy, giving his writing a distinctive place among works of its kind. Yanji has often been classified among later works on calligraphy theory and retains some reference value for the study of ancient calligraphic concepts and the tradition of connoisseurship. Owing to the scarcity of relevant materials, details of his life and intellectual background remain to be further investigated.
