Ancient excellent physicians did not pre-formulate fixed prescriptions. Why? Because the onset and progression of diseases are infinite, whereas the number of prescriptions is finite. If incompetent practitioners were confused by similar yet distinct symptoms and applied these fixed prescriptions indiscriminately, the harm would be severe. Only Zhang Zhongjing’s *Shanghan Lun* (Treatise on Cold Pathogenic Diseases) meticulously details both disease manifestations and corresponding prescriptions, and further provides methods for modification, addition, reduction, and adjustment to anticipate future changes. Alas! The profound intention of a benevolent person cannot be achieved unless one possesses divine insight and exquisite skill. Pang Anchang further worried that there were cases with symptom descriptions but lacking corresponding prescriptions; thus, he continued to write several volumes of treatises. His dedication and medical expertise, without emulating ancient masters, how could he have reached such heights? People in Huainan say that Pang Anchang can "speak with" cold damage (indicating his mastery over the pathogenesis of cold damage), is this not true? I am about to leave Huangzhou. Luan Zhongshi, succeeding as the Vice Prefect of Huangzhou, requested me to inscribe a postface written by his father. His father was a physician who had mastered the subtleties of Master Pang’s art. What do you think? (From Zhang Lei’s *Keshan Ji*, Volume 44)