Regarding the pathway and distribution of twelve channels， the current general view emphasizes their longitud

inal distribution along the surface of the human body. Based on such a positioning， it is difficult to interpret the three

yin

and three

yang

"opening-closing- pivoting" theory， and the theory of the six channels transmission of externally-contracted febrile disease. Through combing the relevant contents in

The Inner Canon of Yellow Emperor

（《黄帝内经》）， it is proposed that， in addition to the longitudinal regional distribution of the channels on the human body， they also exhibit characteristics of layered distribution between the exterior and interior. The formation of this theory stems from the combination of body tissue and channels， that is， the

taiyang

governs the function of skin，

yangming

governs the function of flesh， and

shaoyang

governs the function of bone；

taiyin

governs the function of spleen and stomach，

jueyin

governs the function of liver， and

shaoyin

governs the function of heart. The process of integration of the channels with the body tissues has a relatively clear imprint in the syndrome differentiation of febrile disease in

The Inner Canon of Yellow Emperor

. The exterior-interior relationships of channels are the foundation and prerequisite for the theory of the three

yin

and three

yang

"opening-closing-pivoting" and the theory of the six channels transmission in

Plain Questions·Treatise on Heat

（《素问·热论篇》）.