The so-called six evils are the general name of six exogenous diseases and evils: wind, cold, summer heat, dampness, dryness and fire. The phase shift of Yin and Yang, especially the phase shift in cold and summer, and the climate change have certain rules and limits. If the climate change is abnormal, the occurrence of six qi is more or less, or sometimes there are qi, and the climate change is too sudden; When it exceeds a certain limit, the body can't adapt, which will lead to the occurrence of diseases. In this way, the six qi changed from harmless to harmful and became a pathogenic factor.

The seven emotions are joy, anger, worry, thinking, sadness, fear and surprise. The seven emotions are closely related to the functional activities of zang-fu organs. The seven emotions belong to the five internal organs, represented by joy, anger, thinking, sadness and fear, and are called "five aspirations". The seven emotions are different reflections of the human body on external objective things, and are normal phenomena of life activities, which will not make people sick. However, under the sudden, intense or long-term emotional stimulation, it is beyond the normal range of physiological activities, but it can not adapt, which will lead to the disorder of viscera and blood functions, thus leading to the occurrence of diseases. At this time, the seven emotions become the pathogenic factor and one of the main factors leading to internal injuries, so it is called the seven emotions of internal injuries.