Yi Zhongtian, a Xiamen University professor, speculated that Cao Cao was probably trying to console himself after mistakenly killing Lü Boshe's family by speaking in a regretful tone ("heartrendingly remarked").
Yi Zhongtian, a professor from Xiamen University, commented on this incident in his book Pin San Guo (品三国) in response to criticism from Fudan University history professor Zhou Zhenhe (周振鹤) and a web user called "Hongchayangweili" (红茶杨威利), after he said in a lecture on the television programme Lecture Room that "Cao Cao's rights to the invention of the Empty Fort Strategy had been stolen from him" (referring to this incident in 195).