Mend the Fold After a Sheep is Lost 亡羊补牢

The Chinese expression 亡羊补牢 (wang2 yang2 bu3 lao2) literally means mend the fold after finding a missing sheep. It comes from a story about the King of Chu during the Warring States Period (475-221 BC).

During this period, the State of Chu was not very powerful and the King and his senior court officials were incompetent and morally corrupt. They indulged themselves and did not attend to the important affairs of state. Zhuang Xin, one of the King's ministers, feared the State of Chu was headed for disaster if the King did not quickly mend his ways. So he tried to persuade the King to change, but the King flew off the handle and accused Zhuang Xin of being disloyal.

Zhuang Xin tried to explain that he was actually trying to do the right thing, but the King would not have a bar of it. Seeing the writing on the wall, Zhuang Xin asked the King for leave to visit the State of Zhao and stay there for a while. The King granted him the leave.

Five months later, the King of Qin sent his troops to invade Chu and occupied a large piece of its territory. The King of Chu was forced into exile. The King realised that he needed some open and honest advice if he was to ever going to get things back on track, so he sent his men to fetch Zhuang Xin. Zhuang Xin gave the King the following advice: It's not too late if you mend the sheepfold when you find a sheep is missing. He then made some good suggestions designed to recover the lost land and give the State of Chu a new lease of life.

The idiom is used by the Chinese to advise people that even if they make a mistake and suffer losses as result, they can still remedy the situation by drawing lessons from the mistake and acting quickly to correct it.