The principle of magical correspondence in TCM is called wu xing (五行) in Chinese, and is known as the Five Phases/Elements Theory in English. It can be summarized as follows:
1. Everything (including our organs) is ruled by one of 5 entities: Water (水), Wood (木), Fire (火), Earth (土), and Metal (金) —which are also the Chinese names for the planets Mercury, Jupiter, Mars, Saturn, and Venus. 2 For instance, the heart is ruled by Fire (Mars), the liver by Wood (Jupiter), etc.
2. There is a sympathetic connection (or resonance) between things that are ruled by the same entity (or planet). For example, the heart is connected with the color red, the direction south, the summer season, a bitter taste, and the feeling of joy —because all of these are ruled by Fire (Mars).
3. All 5 entities are interconnected and act on each other. Disease is understood as a result of either the over-,or under-influence of one entity on another. For example, digestive disruptions can be attributed to “Wood overacting on Earth.”
The concept map (pictogram) of wu xing is often drawn by placing the 5 entities in a circle, and then connecting them according to the lines of influence. The connecting lines create a “pentacle,” or a pentagram within a circle.