Confucius said in the Analects of Confucius: When three people walk together, they must have me as their teacher.

This sentence means: Among the three walking people in front, there must be someone who can be my teacher.

Of course, Confucius said this out of modesty. However, it does make sense. Why does it make sense? Everyone has heard this story (Two Children Debating the Sun). This story tells about the problem of two children that stumped Confucius. As the saying goes, live until you are old and learn until you are old, and there are still three points that you have not learned. A person's energy is limited. Maybe someone else has learned the three points you didn't learn, and then others know more about this three points of knowledge than you do.

Confucius wanted to teach people to be humble and to be diligent in asking others questions they don’t understand.