What does "tu si gou peng" (the rabbit dies, the hound is cooked) mean, with a detailed explanation of its origin and allusion

"Tu si gou peng" is a widely circulated Chinese idiom. Its literal meaning is that once the rabbits have all been hunted out, the hunting dog loses the prey it can chase, has no more value to exploit, and is then boiled and eaten by people. It is used as a metaphor for how, after a matter succeeds, the people who once contributed effort instead end up cold-shouldered, abandoned, or even killed, and it is mostly used to describe the fate of those who rendered great service.

This idiom first came from the Records of the Grand Historian. In the late Spring and Autumn period, after King Goujian of Yue destroyed Wu and restored his state, the strategist Fan Li knew well that the King of Yue could share adversity but found it hard to share ease, so he retired after success and reminded his colleague Wen Zhong that when the flying birds are all shot, the good bow is put away, and when the cunning rabbits are all dead, the hunting dog is cooked, urging him to leave as early as possible. Later, when the famous early Han general Han Xin fell from power, he also voiced the lament that when the cunning rabbit dies, the good dog is cooked, which made this saying even more widely known.

In usage, "tu si gou peng" is a derogatory term, mostly used as a predicate and attributive, and is often used together with or interchangeably with expressions such as "when the birds are gone, the bow is put away", "kill the donkey once the milling is done", and "cross the river and tear down the bridge". In modern times, besides commenting on the phenomenon of emperors and kings killing meritorious officials in history, people also use it to describe situations such as a partner being kicked aside after cooperation ends, or an employer tearing down the bridge after crossing the river.

When using it, note that "tu si gou peng" focuses on pointing out that people who contributed effort are abandoned or even harmed, while "when the birds are gone, the bow is put away" focuses on being shelved and put away after losing use value. The two have similar meanings but each has its own emphasis, and they are often used together. The key to understanding this idiom lies in the interdependent relationship of interests between the rabbit and the dog: once the prey is gone, the dog's value naturally disappears along with it.