In Su Wen's Secret Sutra of Linglan, it is pointed out that the heart plays a vital role in the human body, and it is described as "the official of the monarch, and the god comes out." This is because the heart has the function of commanding the viscera of the whole body and controlling various physiological activities of the human body. It is also closely related to people's spirit, consciousness and thinking activities. If the heart function is normal, then people's mental state will be full, their thinking will be agile and their emotions will be stable.