How did Zhouyi come from?

Eight diagrams, not only big hexagrams, small hexagrams, but also Chinese hexagrams. Zhou Wenwang practiced the Eight Diagrams Pai into 64 hexagrams, and Confucius added 10 overlapping hexagrams, describing the natural change law of everything in the world. The divination tool is San Qian; Small hexagrams are composed of four images arranged and combined into 16 stacked hexagrams, which are specially used for divining folk trivia. Divination tools are two hexagrams opposite to the angle. China divination is composed of four images and eight diagrams, and San Qian uses divination tools comprehensively. Only those who know the knowledge of big hexagrams and small hexagrams can operate; People generally don't use it. In fact, when the sixty-four hexagrams were rehearsed in the commercial prison, they were generated according to the two hexagrams of Yin and Yang generated by Taiji. Each hexagram was added with a yang or a yin, and gradually evolved into sixty-four stacked hexagrams. As shown above: