Nourishing the mother for deficiency (treating the mother’s organ by nourishing the deficiency of one of the five organs) and diarrhea of the child for reality (treating the child’s organ by diarrhea of the reality of one of the five organs) are the basic treatment principles of Chinese medicine in treating illnesses by applying the law of the Five Elements in a clinical manner. To replenish the mother in case of deficiency means that in case of deficiency of an organ, not only must the organ be replenished in order to recover, but at the same time, it should also be replenished in accordance with the order of the five elements, so as to promote its recovery through the effect of “phasic life”. When there is deficiency, tonifying the mother is applicable to the deficiency of the mother-child relationship, such as when there is a deficiency of liver blood, in addition to tonifying the blood of the liver, it can also be used to tonify the essence of the kidneys, i.e., to promote the recovery of the liver blood through the effect of “water begets wood”. The actual diarrhea of its son refers to the real disease of an organ, not only must be diarrhea to remove the hyperactive qi of the organ, but also based on the order of the five elements, diarrhea of its “child organ” to diarrhea the hyperactive qi of its “mother organ”. In fact, the diarrhea of the child is applicable to the mother-child relationship, such as liver fire, in addition to clearing and diarrhea of the liver fire, but also clearing and diarrhea of the heart fire in order to eliminate the overactive liver fire.