Zhu believes that "the heart of Tao" is based on justice or the meaning of life, and it has the heart of benevolence, righteousness, courtesy and wisdom. Just show compassion, shame, right and wrong, and resignation. "People's heart" is based on selfishness, which refers to hunger and thirst for food. If so, a saint can't be ruthless. However, saints focus not on people's hearts, but on the hearts of Tao. He believes that the relationship between "Tao Xin" and "people's heart" is both contradictory and related, and that "Tao Xin" needs to be solved through "people's heart", and there is a master-slave relationship between "Tao Xin" and "people's heart", which must be obeyed. Based on the theory of mind and nature, Zhu discussed the issues of justice and human desire. He believes that people have selfish desires, so there is danger; The heart of Tao is the principle of nature, so it is subtle. To this end, Zhu put forward the idea of "restraining human desires and preserving justice" Zhu acknowledged people's legitimate desire for material life and opposed Buddhism's universal advocacy of no desire. He opposes material desires beyond the conditions of continued existence.