It comes from the couplets written by Xie Jin in the Ming Dynasty.
It is a metaphor for a derogatory couplet, describing an arrogant and complacent person who does not do things in a down-to-earth manner and prefers to be vain and vain; he is exaggerated and mean, but has no knowledge or real skills. It is used to satirize people and discuss things, hoping that people can behave in a down-to-earth manner.
Quoting Mao Zedong's "Reforming Our Learning": "There is a couplet that depicts this kind of people. The couplet says: Reeds on the wall are top-heavy and have shallow roots; bamboo shoots in the mountains have sharp mouths and thick skin. The belly is empty. "Extended information
Story
Xie Jin was smart and studious since he was a child. He was good at poetry and writing at the age of 7, and he was upright by nature. Li Shangshu, who retired from old age and returned to his hometown, did not believe that Xie Jin was such a talented person. He invited several powerful officials to write poems for a banquet, and sent someone to call Xie Jin to deal with it, hoping to deliberately ridicule him in public.
The couplets in the middle are very exciting. Xie Jin is able to deal with them one by one without losing his talent, which makes the minister and other dignitaries feel useless. At the end of the day, as the closing couplet, Xie Jin raised his glass and toasted, saying: "It's rare for so many talents to gather together today, I would like to inscribe and present a couplet to cheer up." After hearing this, the minister hurriedly asked someone to bring the four treasures of the study, Xie Jin waved his brush and ink, then threw the pen and left laughing. Everyone came over and took a look, and were dumbfounded and speechless for a long time. It turned out that this was an allegorical couplet: "The reeds on the wall are top-heavy and have shallow roots; the bamboo shoots in the mountains have sharp mouths, thick skins and hollow bellies."
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