Take fifty steps to laugh at a hundred steps! Where does this allusion come from?

From "Mencius: King Hui of Liang, Part 1", the phrase "laugh at a hundred steps at fifty steps" means that during a war, a person who runs back fifty steps laughs at a person who runs back a hundred steps for being cowardly. .

"Mencius · King Hui of Liang 1": King Hui of Liang said: "I am in charge of my country, and I only have my heart and ears. If there is a bad situation in Henei, I will immigrate to the east of the river, and move my millet to the east of the river. The same is true for the bad situation in the east of the river. . Observing the policies of neighboring countries, it is not as good as the people of the neighboring countries. If the people of the neighboring countries are not reduced, why not increase the people of the people? After catching the sword, he abandoned his armor and started to move forward, or he stopped after taking fifty steps. What if he took fifty steps and laughed at a hundred steps? He said: "If the king knows this, he will have no hope of having more people than his neighbors." Allusion During the Warring States Period, the princes and kingdoms all adopted the strategy of uniting vertically and horizontally, making contacts at a distance and attacking at a close distance. War continues year after year, which brings suffering to the people of all countries. Mencius saw it and decided to travel around the country to persuade those warlike monarchs. Mencius came to Wei and met with the warlike King Hui of Liang. King Hui of Liang said to Mencius: "I have tried my best to govern the country and love the people, but I don't see the number of people increasing. What is the reason?" Mencius replied: "Since King Hui of Liang loves war, let me use war as an analogy. ! When two armies meet on the battlefield, there will inevitably be a fight. The defeated party will inevitably throw away his helmet and flee for his life. If a soldier runs slowly and only runs fifty steps, he will run away. A soldier who has reached a hundred steps is greedy for life and afraid of death." After Mencius told the story, he asked King Hui of Liang, "Is this right?" King Hui of Liang immediately said, "Of course not! He just didn't go a hundred steps. But it is also an escape." Mencius said: "Although you love the people, if you like to fight, the people will suffer. This is the same as the fifty steps.

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