Health preservation, as ancient sages often said, "nourishes nature", what kind of "nature" do they raise? Sun Simiao pointed out in "Preface to Cultivating Sexuality": "A husband who cultivates sexuality wants Xi Zhi, and his nature is good." "Since human nature is good, all internal and external diseases are naturally not born, and disasters are unprovoked. This is also a big lesson in nourishing nature. "

It can be seen that the cultivation of nature is mainly moral cultivation characterized by goodness, which is also an important aspect of one's moral cultivation, that is, the so-called "goodness and moral construction" in Guoyu.

A kind-hearted person, who is proud of his dedication and ready to help others, can inspire people's love and gratitude for him, thus gaining inner comfort and happiness, alleviating negative emotions such as anxiety and tension, and helping to maintain the harmonious balance between zang-fu organs and Yin and Yang and maintain physical and mental health. Doing good deeds can also directly bring happiness to people, because doing good deeds is another realization of self-worth, which can meet people's spiritual needs of self-realization. Therefore, Zhang Jingyue, a great doctor in the Ming Dynasty, said in "The Complete Book of the Pure Moon and the Record of Nakagawa": "Only happiness can keep you healthy, and those who want to be happy are nothing more than goodness."