During the Three Kingdoms period, after Emperor Wen of Wei, Cao Pi, ascended the throne, he harbored deep suspicions towards his brother, Cao Zhi, and constantly sought opportunities to harm him. However, due to the intervention of their mother, Cao Pi was prevented from executing Cao Zhi.

Frustrated by his lack of opportunity to use his talents, Cao Zhi wrote a petition. In it, he mentioned that Yi Yin, a humble minister who came with the dowry, and Lü Shang, who worked as a butcher and fisherman, both found like-minded patrons in Shang Tang and King Wen of Zhou, respectively. They then helped these rulers achieve great undertakings.