As one of notable works of HUANG Yuanyu， a renowned physician from the Qing Dynasty，

The Indications of Classics by Four Medical Sage

emphasize the theoretical paradigm of “one

qi

circulation” with a particular focus on the middle

qi

. Building upon disease differentiation and treatment， HUANG Yuanyu attaches great importance to understanding the underlying cause of the disease. It is believed that the imbalance of the six climatic factors is the fundamental cause of diseases. The concept of mutual interaction between the physiological and pathological aspects of the six climatic factors is proposed to grasp the basic pathogenesis. Based on the individual's specific condition of six climatic factors， excess or deficiency， specific prescriptions are formulated. The diagnosis and treatment system can be summarized as a “differentiation of diseases → disease etiology → differentiation of the condition of six climatic factors → individualized pathogenesis of traditional Chinese medicine （TCM） → prescription of TCM” model based on the holistic view. HUANG Yuanyu' s diagnosis and treatment system is highly practical and can provide reference for clinical diagnosis and treatment of diseases in TCM.