The human body has its origin, just as wood has its root and water has its source. The kidneys are the root of vitality, and the spleen is the source of vitality. In other words, “the kidney is the root of innate nature, and the spleen is the root of acquired nature”. “The kidney is the origin of the innate, the spleen is the origin of the postnatal”, which is mainly reflected in two aspects of physiology and pathology: a. Physiologically, the spleen and kidney help each other, then the shape is full of body health 1. The kidney is the main reservoir of essence, and the essence it collects includes the innate essence and the acquired essence. The essence in the kidney governs and regulates the growth and development of the human body, the maturation of reproductive functions and the physiological functions of the human body. 2, “the spleen is the essence of the latter” refers to the fact that people are based on grain, that is, “if the grain is safe, it is safe, if it is not, it is dead”. Once a person is born, the internal organs of the human body need sufficient material and energy for functional activities and growth and development, and the water and grain essence produced by the diet is the main source of nutrients needed to maintain life activities since birth. The spleen is the main organ of transportation and transformation, and the stomach is the main organ of reception, both of which are “officials of the granary”. After the food is cooked and ground by the stomach, the essence is absorbed by the spleen, transferred to the lungs and spread throughout the body, nourishing the organs and limbs. 3. The kidney collects essence, which is the origin of life; the spleen is the master of transportation, transforming qi and producing blood, which is the source of qi and blood. The first and second days complement each other and promote each other. The first day warms and stimulates the second day, the second day supplements and nurtures the first day, the first day helps the second day, the second day helps the first day. 4. The essence of the kidney depends on the cultivation and enrichment of the water and grain essence in order to constantly fill up and mature, while the spleen and stomach transform the water and grain essence with the help of the warmth of the kidney yang. The first and second days are healthy and abundant in order to maintain the normal vital activities of the body. Pathologically, the spleen and kidney are out of tune and affect each other. 1, weakness of the spleen and stomach can lead to yin and fire: the spleen and stomach yang is weak, the vital energy is insufficient, the qi is sunken in the kidney, so that the lower jiao is free from the phase of fire to take advantage of the internal burnt yin and fire, and the evidence of “heat in”. 2, the kidney yang weakness, can lead to the spleen yang invigoration: the kidney is the main yang, the spleen yang rooted in the kidney yang, the kidney is not solid, the spleen does not rise clear, can lead to the spleen and kidney yang deficiency of diarrhea and edema and other evidence. 3. The spleen and the kidney, the acquired and the congenital, must be mutually gifted and promote each other: if the kidney yang is insufficient to warm the spleen yang, the spleen yang will not be invigorated; if the spleen yang is deficient for a long time, which in turn damages the kidney yang, the kidney yang will also be deficient, leading to deficiency of both the spleen and the kidney. In short, the congenital and the acquired are mutually supportive of each other, as the human being depends on the congenital at the beginning of life, and the human being depends on the acquired; the kidney essence is nourished by the transportation of the spleen, and the transportation of the spleen depends on the kidney yang to warm it. Both are closely related physiologically and pathologically, and the congenital and postnatal are complementary to each other, together completing the complex life activities of the human body.