Many of the most important ideas in TCM are based on the teachings of Daoism. Based on the teachings of TCM, it is important to balance the five elements in a person's body: wood, fire, earth, metal, and water. Each element also has something called "yin" and "yang", or opposite values that must exist alongside each other rather than to overcome the other. The way to balance the "yin" and "yang" is to strengthen "qi", or an invisible force that brings balance to the "yin" and "yang". Knowing the five elements and the "yin" and "yang" is important because each organ of the body is related to one of the five elements. It is important to strengthen a person's "qi" because balancing the "yin" and "yang" of a person's organs is important for people to be healthy. The different treatments in TCM are made to bring balance to the elements in a person's body.