"Huashu", a Taoist work, was written by Tan Qiao in the late Tang and Five Dynasties. "He expounded the moral principles of Huang Lao in many books, and his writing style is simple, vigorous and profound." Connoting physics, chemistry, biology, medicine and other sciences, he can be said to be an amazing ancient scientist. ***Six volumes, divided into six elements: Dao, skills, virtue, benevolence, food, and frugality, one hundred and ten chapters. The main theme of its content is based on Huang Lao Liezhuang's thoughts and integrates Confucianism. The book believes that the world is rooted in "empty", which transforms into gods, spirits into qi, and qi into forms, and finally returns to emptiness. "Void" is both the origin and the destination of all things. The emptiness and things are in a cyclical and transforming relationship. You can enter the realm of eternal life where "gods may not be transformed, and forms may not be born". The book also spends a lot of space discussing social evolution, revealing the causes of unrest and proposing countermeasures. In terms of content, the book basically develops Huang Lao Liezhuang's theory, which believes that the world is changing all the time, and everything is born from emptiness and then turns into emptiness. The inexhaustible transformation, like the endless rings, all come from the Tao, and based on this, the idea of ??cultivating the Tao and becoming an immortal is expounded. Although it is a Taoist book, it also involves many socio-economic and political discussions at that time. It also has some knowledge about concave and convex mirrors, covering a wide range of areas. Ideologically, this book has a social and historical outlook that sympathizes with the people; it inherits traditional Taoist thought and is greatly influenced by Liezi's thoughts such as Zihua and Daotian. It occupies an important position in the history of Chinese thought. Tan Qiao's "Book of Changes" has had a profound impact on Chinese classical aesthetics. Later, as one of the important Taoist classics, it was included in the Taoist book collection "Tao Zang".