What does the Yin and Yang of Eight Diagrams mean in Taiji?

This problem should be explained as follows: 1. Yin and Yang are a pair of categories in China's ancient philosophy. The original meaning of yin and yang is very simple, indicating that the sun faces the back, the sun faces the sun, and the back faces the sun. Later, it was extended to the warmth and coldness of the climate, the up and down or so, the internal and external directions, and the restlessness and tranquility of the movement state. 2. Philosophers in ancient China further realized that all phenomena in nature are antagonistic and interactive, so they used the concept of Yin and Yang to explain two kinds of antagonistic and interactive material forces in nature, and thought that the opposition and fluctuation of Yin and Yang were inherent in things themselves, and then thought that the opposition and fluctuation of Yin and Yang were the basic laws of the universe. 3. Yin He not only represents opposing things, but also can be used to analyze two aspects of internal opposition. Generally speaking, everything that is vigorous, extroverted, rising, warm and bright belongs to Yang; Relatively quiet, defensive, healthy, cold and dark belong to yin. In terms of heaven and earth, the weather is light and bright, and the atmosphere is heavy and turbid. In terms of fire and water, water is cold, nourishing subordinate yin, fire is hot, and inflammation belongs to yang.