If one is mentally optimistic, his energy will be smooth and spirit vigorous; if one is depressed, his energy will be stagnant and spirit sagging; if one's emotions of joy and anger are not restrained, his energy will be exhausted and spirit waned. Therefore, keeping a clear mind and few desires can make one's heart energy peaceful, blood circulation smooth, and spirit calm, so that even with great shock or sudden fear, it cannot do harm. The method of regulating spirit includes practicing Zen meditation, having something to rely on mentally, entertaining oneself with music and singing, or exploring the mysteries of mountains and forests, so as to maintain a graceful demeanor, a calm mind, leisurely aspirations with few desires, a peaceful heart without fear, then the spirit can be regulated.