Yang Xiu
In Chapter 60, Liu Zhang sends Zhang Song as an envoy to meet Cao Cao in Xuchang. Zhang Song ridicules Cao Cao in front of his registrar, Yang Xiu. Yang Xiu shows Zhang Song the "New Book of Mengde" (孟德新書), a military book written by Cao Cao and based on "The Art of War". Zhang Song looks through the book and laughs and says, "Even young children in Shu can recite this book, how can it be a "new book"? This book was written by an anonymous writer during the Warring States period. (Cao Cao) plagiarised the book, and people like you are deceived by him." Zhang Song then recites the book verbatim to Yang Xiu. When Yang Xiu tells Cao Cao about the incident later, Cao Cao tears the book and burns it. The book was later found in a basin of ginger presented to Cao Cao by the sage Zuo Ci.