It comes from chapter 1 1 of Yi Zhuan Cohesion Uploading, and was later learned by Confucius during the Warring States Period. The original text wrote: "Therefore, it is easy to have Tai Chi, and it is to give birth to two instruments, two instruments give birth to four elephants, and four elephants give birth to gossip, which will determine good and bad luck, and good and bad luck will give birth to great cause."
Vernacular translation: So Tai Chi contains Yin and Yang and is divided into two parts, so Tai Chi gives birth to two devices. Tai Chi gives birth to Yin and Yang, which is transformed into four images: Taiyin, Sun, Shaoyin and Shaoyang. From this, eight diagrams evolved, namely: Gan, Kun, Zhen, Gen, Li, Kan, Jiao and Xun. Gossip determines the quality of things and leads to great development.
Extended data:
"Tai Chi gives birth to two instruments, and two instruments give birth to four images" first came from the Book of Changes.
Tai Chi is the first two steps for China's philosophy to understand the world. From scratch, Tai Chi gives birth to two devices, and "life" means performance. Taiji evolved into two instruments, and then two instruments gave birth to four images, and four images gave birth to gossip. Everything in the world is born of yin and yang of heaven and earth.
In Song Dynasty, Zhang Zai thought that two instruments refer to yin and yang and two qi, and "one thing (Tai Chi) and two bodies (two instruments) are also qi". Regardless of qi and chaos, it is called "Tai Chi"; Divided into yin and yang, it is called "two instruments". Yin and yang feel each other, moving and changing.
According to Yi Zhuan, the formation and changes of all things are caused by the ups and downs of Yin and Yang, the combination of rigidity and softness, the opposition between motion and static, mutual resistance and friction oscillation, that is, "Yin and Yang are the Tao" and "the combination of rigidity and softness produces changes".
Baidu Encyclopedia-Taiji gives birth to two instruments, and two instruments give birth to four images.