"One yin and one yang is the Tao", and the Book of Changes is named after "Yi" because the Book of Changes is a study of yin and yang, and the word "Yi" itself is a synthesis of yin and yang. There are eight strokes of the word "Yi", which corresponds to gossip. It consists of two words: day and month. The word "day" is yang and sun, and the word "month" is yin and night, with yang above and yin below, which highly summarizes the basic principles of the Book of Changes.

From the content point of view, the Book of Changes involves all aspects of the universe, and the two stars "Sun" and "Moon" are symbols of the universe and have the closest relationship with human beings. This shows how great our ancestors were. There is a cloud in the Book of Changes: "It is easy to have Tai Chi, and two instruments are born. Two instruments give birth to four elephants, and four elephants give birth to gossip. " This sentence shows that China's ancient cosmology believed that the original world was a chaotic point, that is, Tai Chi. Later, under the interaction of yin and yang, four basic phenomena were gradually born, namely, less yin, less yang, lunar and sun, which correspond to the four directions of east, south, west, north, spring, summer, autumn and winter, as well as Qinglong, white tiger and Suzaku. These four images have developed into eight basic hexagrams, namely, Gan, Kun, Kan, Li, Zhen, Gen, Xun and Hui.

By observing and analyzing the information of the ups and downs of Yin and Yang, people can find out the general laws of the movement of everything in the universe. Zhou Wenwang deduced sixty-four hexagrams by overlapping eight diagrams, and gave them specific hexagrams, which explained the development and change law of the universe in more detail.

Confucius in Wen Sheng inherited and developed the theory of the Book of Changes, raised the Book of Changes to the philosophical level, and was regarded as the magic weapon of governing the country by the ruling classes in past dynasties, becoming the first book in China.

The reason why the Chinese nation has not been destroyed by disasters like many ancient civilizations in the world, but has been in the same strain for five thousand years, and it has been developing and growing continuously, which is closely related to our grasp of the Yi-ology thought. It is precisely because of adhering to the thought of China's Yi-ology culture that Yin and Yang echo each other, combining rigidity with softness that we can constantly strive for self-improvement, cherish morality and pass on the seeds of civilization from generation to generation.