Both Mencius and Xunzi belong to Confucianism, and both men's judgment of human nature as good or evil is an expansion of Confucianism's core benevolence. Mencius and Xunzi believed more in their subjective judgments than Confucius' reverence for ritual and education. Mencius's theory of the original goodness of human nature was significant on the ethical and moral level, and it contributed to the development of people-oriented thinking under Chinese thought. Xunzi's theory of evil human nature is prominent in its political service characteristics. The purpose of Xunzi's moral education and the ritual government is to effectively manage the people and the legitimacy and effectiveness of the king's rule. Unlike Mencius's and Xunzi's judgment of the nature of humans, Western ethics places more emphasis on the judgment of the value of man, which leads to theories of man's state of existence and developmental needs. From this, we can see that ethics and the planning of human existence and development have similarities and different developmental orientations in China and the West's different cultural and historical environments. Mencius and Xunzi attached importance to the self-moral development of man, surrounding the development of man's mind and reality, thereby deriving the corresponding rules of ethical and moral order and political system. Western Aristotle, Aquinas, Hobbes, and Rousseau judged the moral needs and moral values of human beings and then generalized how to better realize the moral development of human beings and the creation of moral values. All of them have explored the existence and development of human beings at the level of ethics and political philosophy and use ideas and theories to build the corresponding realistic order and conditions better to promote the moral development of human beings and society.