The doctrine of five evolutive phases and six climatic factors （abbreviated as the doctrine） is described in large amount of text in the

Inner Canon of Yellow Emperor

（《黄帝内经》）， accounting for nearly 1/4 of the length of

Basic Questions

（《素问》）. The description of pathological mechanism， treatment and others have extremely high value for guiding the clinical practice. Based on the classic

Origins of Medicine

（《医学启源》） by ZHANG Yuansu of the

Yishui

（易水） School， this paper discussed his inheritance and development of the doctrine in the

Inner Canon of Yellow Emperor，

using the method of textual research. It is believed that ZHANG Yuansu not only takes full advantages of the doctrine， but dares to break through and innovate. He uses the “the main treatment method of six

qi

” to unify the complexity of “six

qi

as a disease” in the doctrine， and clarifies the ascending and descending theory of

qi

and flavor in the doctrine with “the diagram of the ups and downs of

yin

and

yang

， the thick and the thin， the cold and the hot”， and uses “preparation based on five phases and generation and restriction cycles” to govern the treatment method of the five flavors in the doctrine. Based on these， he establishes the system of theory-law-prescription-medicine， which is characterized by “differentiation of the diseases and prescription of the formulas based on

zang

-

fu

（脏腑） organs” and “understanding the herbal medicine with analogy”， and has created the

Yishui

School with a profound influence on later generations.