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The word "harmony" comes from The Book of Rites, which is an educational paper in ancient China, an article in The Book of Rites, a monograph of ancient laws and regulations in China, and the earliest document devoted to education and teaching in the history of the world. It is generally believed that this is the work of China Meng Si School at the end of the Warring States Period. According to Guo Moruo's textual research, the author is Ke, a student of Mencius.

This paper expounds the purpose and function of education, the system, principles and methods of education and teaching, the position and function of teachers, and the relationship between teachers and students and classmates in the process of education, and systematically and comprehensively summarizes the educational experience of pre-Qin period in China. He is concise, vivid in metaphor, fluent in style and artistic to some extent.

The Book of Learning is one of the Book of Rites, which was written from the 4th century BC to the 3rd century BC. According to Guo Moruo's textual research, its author may be Ke, a student of Mencius. Gu Shusen supported Guo Moruo's view that Xue Ji was written by Le Zhengzi, a Confucian scholar, at the end of the Warring States Period, and borrowed ideas from the school, probably by Ke, a disciple of Mencius.

Gao Shiliang also agrees with this view, thinking that Xueji is a work of the Warring States period, and the specific time is in the late Warring States period. Its author should be Ke, because Ke is Mencius' favorite pupil and deeply influenced by Mencius' thought. Secondly, Le Zhengzi also studied under Zeng Shen, "Le Zhengzi said that I had heard of Ceng Zi". Third, the original music is a scholar, and the Book of Rites says:' Music is advocating four skills and establishing four religions. The descendants of academic officials all have family origins in education. "