[Academic perspective on a classic acupoint pair: Hegu (LI4) and Taichong (LR3)]

Hegu (LI4) combined with Taichong (LR3) is a classic acupoint pair in science of acupuncture and moxibustion, widely recognized in academic circle as "four-gate points". Through conceptual tracing and textual research, it is determined that: XU Feng, the master of the Ming Dynasty, provided the annotations for Biao You Fu (Song to Elucidate Mysteries) chapter in Zhenjiu Daquan (The Complete Compendium of Acupuncture and Moxibustion), and he specified that Hegu (LI4) and Taichong (LR3) were the acupoints for "opening four gates". It is the beginning of the association between"four gates" and the two acupoints. However, these two acupoints were not commonly used as paired points by medical masters before that time. Medical texts of later ages further elaborated on this annotation, evolving the functions of Hegu (LI4)and Taichong (LR3) from merely "opening four gates" to encompassing both the concept of the "four gates" and the specific term "four-gate points". Even though, after specifically emphasized by XU Feng, this pair of acupoints had not been increasingly used in clinical practice. At that time, these two acupoints were primarily utilized in accordance with their respective therapeutic indications and their application was rarely guided by the theories such as "four gates", "four-gate points" and "opening four gates". Nowadays, the combination of Hegu (LI4) and Taichong (LR3) has been supported by the clear academic rationale. Such combination adheres to relatively rigorous principles of traditional acupuncture-moxibustion theories. Thus, it is concluded that theoretical construction and clinical practice do not represent a simple one-way relationship of "experience upgraded to theory". Academic research in acupuncture and moxibustion should distinguish between "the formulation of theories" and "the validation of theories", and it should be advanced prudently through both historical analysis and contemporary validation, so as to achieve a creative transformation of classical theories.