Humility from Mao Zedong makes people progress, while pride makes people fall behind.
An old saying goes: Fullness brings losses, modesty brings benefits. The phrase comes from "Shang Shu. Dayu Mo", which means - pride and complacency will lead to losses, while modesty and caution will gain benefits. Later, Chairman Mao used the past to serve the present in his article, that is, "humility makes people progress, and pride makes people fall behind."
The focus of this sentence is to emphasize the contrast between humility and pride, and then express it in a more literary language. In our traditional concepts, we appreciate humility in learning and oppose pride and arrogance. With an open mind to learn, you can make progress little by little, but if a person is proud and arrogant, one day he will become more ignorant than others.