《论衡·卷十四·状留篇》
姜太公白了头才显贵；百里奚的智慧，到晚年才表现出来。他们能为国家深谋远虑，因此成了君主的辅佐，但都是些才高德重，很难被提拔任用的人。
吕望之徒，白首乃显；百里奚之知，明於黄发：深为国谋，因为王辅，皆夫沉重难进之人也。
Jiang Taigong showed his nobility only after he became white-haired;百里奚's wisdom was revealed only in his later years. They were able to plan far ahead for the country, and therefore became assistants to the monarch, but they were all people of great talent and virtue, and it was difficult for them to be promoted and reused.