What do water, gold, wood and earth mean in ancient algorithms?

Wood, fire, water, gold and earth are ubiquitous in the world. They interact and develop with each other, maintaining the balance of nature. Wood represents the growing substance; Fire represents a substance that can give off heat energy; The earth represents nature itself; Water represents a flowing substance and can be recycled; Gold stands for solid matter. Wood fire is above the soil, and water and gold are below the soil, so wood fire is yang, water and gold are yin, and soil is neutral.

Second, the five elements:

The Five Elements is a kind of material view in ancient China, which is mostly used in philosophy, traditional Chinese medicine and divination. The theory of five elements is the basic theory of Chinese medicine, which is established by using the characteristics of wood, fire, earth, gold and water in ancient philosophical theories and their laws of birth and grams to understand and explain the systematic structure and methodology of Chinese medicine in nature, so as to explain the relationship between viscera, viscera attributes, movement changes and the relationship between human body and the external environment. "Five elements" are closely related to "five internal organs" and "five aspirations". When the five elements can't maintain the physiological balance of mutual generation and mutual restraint, the relationship between generation and restraint is transformed into a relationship of bullying, thus resulting in corresponding related diseases.