Yu Rang served the noble families of Fan and Zhonghang. When Zhi Bo destroyed them, Yu Rang went over to Zhi Bo. Later Zhi Bo was killed by Zhao Xiangzi, and Yu Rang tried again and again to kill Zhao Xiangzi. “A gentleman dies for the one who knows him,” he said. “A woman makes herself beautiful for the one who delights in her.” (士為知己者死，女為說己者容)
Zhao Xiangzi asked why he took such deep revenge for Zhi Bo, when he had done nothing for his first masters. Yu Rang answered: “The Fan and Zhonghang treated me as an ordinary man, so I repaid them as an ordinary man. Zhi Bo treated me as a man of the state, so I repay him as a man of the state.” (Records of the Grand Historian)