This Chapter from The Yellow Emperor's Classic of Internal Medicine details the digestive system's dimensions and capacity, explaining why a person dies after seven days without food. The text describes the size and volume of the stomach, small intestine, large intestine, and colon, calculating their combined capacity for food and water. It then argues that a person's daily waste eliminates the stomach and intestinal contents over seven days, resulting in the depletion of essential fluids and energy, hence death. The text establishes a physiological basis for survival based on the body’s digestive capacity and daily waste output. The author uses this detailed anatomical and physiological description to support the explanation of death by starvation.