Duan Yucai

Duan Yucai (1735–1815), courtesy name Ruoying, was a Chinese philologist of the Qing Dynasty. He made significant contributions to the study of Historical Chinese phonology. Born in Jintan, Jiangsu, he resigned from his government post at the age of 46 to dedicate himself to his studies. As a student of Dai Zhen, Duan Yucai classified Old Chinese words into 17 rhyme groups, proposing that characters sharing the same phonetic component belong to the same rhyme group, based on the rhyming scheme of the *Shijing*. He also theorized the absence of the departing tone in Old Chinese. His magnum opus, the *Shuowen Jiezi Zhu* ("Annotated *Shuowen Jiezi* "), was the culmination of 30 years of work and was published shortly before his death. Praised by contemporaries like Wang Niansun, it is considered a landmark in Chinese philological studies, the most significant since the original *Shuowen Jiezi*.