As an important reasoning mode in the theory construction of traditional Chinese medicine（ TCM）

five-phase theory promoted the formation of TCM theory and brought plain characteristics of system theory and control theory to TCM. However

the five-phase reasoning mode has insurmountable logical defects

mainly manifested in comparability of five-phase classification

attachment irreconcilability of four seasons and five phases

difference between equal rights of five phases and priority of five zang-organs

unidirectionality of five-phase action and complexity contradiction of the relationship of five zang-organs. It is not only difficult to meet the needs of holistic

complex and syndrome differentiation thinking in clinical TCM diagnosis and treatment

but also an obstacle in academic development of TCM to a certain extent. Therefore

for the application and research of the five-phase reasoning mode

we must have a clear and correct attitude

fully understand its limitations

and constantly revise and improve it according to the actual situation in practical activities. We can also try to make use of modern mathematics

mathematical logic and other methods for its explanation or transformation

so as to promote the academic development of TCM.