This Chapter from The Yellow Emperor’s Classic of Internal Medicine explores the concepts of yin and yang, purity and turbidity within the human body. The dialogue between the Yellow Emperor and Qí Bó examines how these opposing forces interact within the twelve meridians, influencing the flow of qi and blood. The text details how pure and turbid qi behave differently, affecting various organs and meridians, and provides guidance on acupuncture techniques to balance these energies. Differentiation between pure and turbid qi is crucial for understanding health and disease. Ultimately, the text aims to elucidate the relationship between the internal energetic balance and overall well-being.