Shanghan Lun

The Shanghan Zabing Lun or the Treatise on Cold Damage and Complex Diseases is considered the forefather of all formula books. The original work was lost to the tooth of time, but most of its contents are preserved in two extant works called the Treatise on Cold Damage shanghan lun and the Concise Essentials of the Golden Cabinet jingui yaolue. The first work primarily addresses externally triggered disorders while the latter work describes the pathology and treatment of complex diseases generated internally.

Chapter seventy-four of the Great Treatise on the Essence of the Utmost Truth zhizhen yaodalun of the Inner Classic of the Yellow Emperor huangdi neijing records the most encompassing and original rules in Chinese medicine pathology. The nineteen patterns, most commonly known as the Nineteen Lines on Pathology, are considered to be the most authoritative instructions on classical etio-pathology and the only discourse where a differentiation method based on the five phase energetics is presented.