Mathematical theoretical system of yin-yang and five phases is composed of three axioms based on theories of yin-yang and five phases and several ten theorems deriving from these axioms. The three axioms is mathematical model of vital movement of human body in a sense of traditional Chinese medicine. Physiological formulas of yin-yang and five phases deriving from some theorems reveal the universal laws of physiological activities of human body. On the basis of these formulas,we can deduce disease before onset from with,and deduce the prescription on the bases of the principle of the yin-yang equilibrium of human body followed by the yin-yang equilibrium of five internal organs and six hollow organs,theory of channel tropism of traditional Chinese medicines and its impact with regard to yin-yang. Furthermore,we can develop application software of traditional Chinese medical science and realize modernization of determination of treatment based on pathogenesis obtained through differentiation of symptoms and signs,thereby traditional Chinese medical science go to the world.

The change and transformation of nature of disease and transmission of a disease are the two core issues of TCM pathology.Satisfactory explanation can be elicited separately from both axiom 1 and axiom 2,3 of mathematics of yinyang and five elements.The crux of the changes of nature of disease mainly lies in the size changes of the clarity of the leading property;but which of transmission of a disease depends on the sign changes of the clarity of the leading property.