Syndrome differentiation and treatment is a main thinking mode for diagnosis and treatment in traditional Chinese medicine （TCM）， and has significant advantages when used in the condition of “different diseases treated in the same way”. However， over-emphasis on syndrome differentiation and treatment tends to overlook the relation of disease， symptom， cause， and mechanism.

Treatise on Cold Pathogenic and Miscellaneous Diseases

（《伤寒杂病论》） holds that “one syndrome is enough” and introduces Chaihu （

Radix Bupleuri

） Decoction-related symptom as an example emphasizing the application of grasping main symptom in clinical diagnosis and treatment， but the direct matching of formulas and symptoms tends to simplify the thinking of diagnosis and treatment. Based on this， the theory of “du cang （独藏， the only core symptom hidden in many symptoms）” has been proposed， for which “du” refers to “the only one”， while “cang” means “deep hidden”. By identifying the only core symptom hidden in many symptoms， deducing simplicity into complexity， the integration of the holistic view of disease differentiation and the precision of symptoms differentiation is realized. Taking the identification of diabetic peripheral neuropathy， latent-

qi

warm disease and obesity as examples， this paper discussed the differentiation and treatment thought of “du cang”， which focuses on distinguishing the main symptoms， takes disease as principle and syndrome differentiation as the hub， examines the causes and inspects the mechanism， integrating “disease-symptom-syndrome-cause and mechanism” so as to guide diagnosis and treatment thinking.