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Shi Nai'an

Many scholars believe that the first 70 chapters were indeed written by Shi Nai'an; however the authorship of the final 30 chapters is often questioned, with some speculating that it was instead written by Luo Guanzhong, who may have been a student of Shi. Another theory, which first appeared in Gao Ru 's Baichuan Shuzhi (百川書志) during the Ming dynasty, suggests that the whole novel was written and compiled by Shi, and then edited by Luo.

Shi drew from oral and written texts that had accumulated over time. Stories of the Liangshan outlaws first appeared in Old incidents in the Xuanhe period of the great Song dynasty (大宋宣和遺事) and had been circulating since the Southern Song dynasty, while folk tales and opera related to Water Margin have already existed long before the novel itself came into existence. This theory suggests that Shi Nai'an gathered and compiled these pieces of information to write Water Margin.