We often say to be a "saint", which is probably the highest pursuit of China traditional literati. But what is the realm of saints? After his own revision, Wang Yangming told us very clearly that a saint is a state in which all the pollution attached to his conscience is removed. This is the "Tao mind" emphasized in Shangshu, which Buddhists call "Buddha nature". But in reality, people's conscience is always mixed with too many human weaknesses, which requires us to practice, and the process of practice is "to conscience." Wang Yangming said: "Knowing is the noumenon of the heart, and the heart will naturally know." Seeing the father naturally knows filial piety, seeing the brother naturally knows the younger brother, and seeing the boy enter the well naturally knows sadness. This is a conscience, not fake. "The so-called conscience is the heart of the Tao, the positive energy in people's hearts, and the process of constantly wiping away the dust on the mind to show the heart of the Tao.