Han Yu put forward the view that saints are impermanent teachers in Teacher's Theory, which is an exploration of the relationship between teachers and students. He believes that people, regardless of seniority and seniority, are qualified to be teachers as long as they have the ability to preach and teach. "Disciples don't have to be inferior to teachers, teachers don't have to be superior to disciples, and teaching and learning have priority", and "a threesome must have my teacher" is the ideological origin of Han Yu's "sage impermanence teacher". "I love my teacher, especially the truth" has become a fine tradition in the history of education in China. This incisive conclusion makes the world theory shine.