Former U.S. Ambassador to Japan, Ralph Stahl, said that in order to understand and surpass Japan, one must first understand Tokugawa Ieyasu. Mr. Bo Yang, on the other hand, believed that: "There are two books in China that can be compared with 'Tokugawa Ieyasu', one is 'Comprehensive Mirror for Aid in Government', and the other is 'Romance of the Three Kingdoms'."