This paper considers the medical thought in Takuan’s philosophy.His medical idea was similar to modern preventive medicine. He thought about a disease as follows: Qi (material force) circulates through a human whole body. When this qi is delayed, a disease occurs. It is necessary to adjust the qi to prevent it from stopping. Thereby it is demanded that the human being becomes mindless (mushin). It may be said that Takuan’s medical thought was based on the theory of li (principle) and qi.
