Once the Middle Qi (Middle Jiao Qi) is deficient, it cannot ascend to generate Metal (Lung) and thus causes coughing; nor can it descend to control Water (Kidney/Fluids) and thus leads to leukorrhea. Generally speaking, for this type of syndrome, although coughing and leukorrhea manifest separately in the upper and lower parts on the surface, seeking their root reveals that Metal (Lung) and Water (Kidney) share the same origin, ultimately all resulting from deficiency of the Middle Jiao. Once the source of the disease is identified, one can naturally predict future pathological developments based on the current primary symptoms, let alone those already manifested. Another question arises: Dongzhuang considers nasal congestion and dripping nose as a welcome sign; what is the rationale? The answer is: Skin and hair are the external correspondence of the Lung. When the Lung loses nourishment, the Couli (pores and interstices) become loose, making it easy for external pathogens to invade. Nasal congestion and dripping nose are, therefore, exterior syndromes of Wind-strike affecting the Taiyang Channel (Taiyang Meridian). Wherever pathogens gather, they first attack the skin and hair; once entering the skin and hair, they immediately affect the Taiyang Channel. Therefore, in cases of external contraction, seeing cough indicates a milder condition; among cough syndromes, having an exterior syndrome indicates a milder condition, because the pathogen...