The debate of the Guwen Shangshu which has continued over the past 300 years, still involves many unsolved problems, such as the meanings of the Confucian classics, classical learning, and critical interpretation, etc., even including historical and political research. These questions concern epistemology and methodology. According to the general conclusion, the commentary to the 25 chapters contributed by Mei Yi were not written by Ma Rong and Zheng Xuan. Zheng Xuan’s admirers in the Qing dynasty, such as Hui Dong, Qian Daxin, Dai Zhen, Wang Mingsheng, Liu Duanlin and Li Dun confirmed that Wang Su forged Jia yu and Kong congzi. Ding Yan (1794-1875), in particular, collected many materials and proved this conclusion in his work Shangshu yulun. Only a few scholars like Chen Li or Liu Shipei challenged Ding’s opinion, until Wu Chengshi (1884-1939) took the contrary position. Rethinking the case, from suspicion to confirmation to negation, we can see some aspects of the learning process in Qing dynasty and modern times.