《资治通鉴·汉纪·汉纪六十》
当初，夏侯渊虽然多次打胜仗，魏王曹操却经常告诫他说： 作为将领，应有胆怯的时候，不能单凭勇猛。
初，夏侯渊战虽数胜，魏王操常戒之曰： 为将当有怯弱时，不可但恃勇也。
At that time, although Xiahou Yuan had won many battles, Wei Wang Cao Cao often warned him: As a general, you should be timid and cannot rely solely on bravery.