"Unity of nature and man" is one of the fundamental concepts of classical Chinese philosophy, which is opposite to the theory of "division of nature and man". The so-called "Heaven", according to one view, includes the following contents: 1. Heaven is an entity that can have a reciprocal relationship with people; 2. Heaven is an entity that bestows good and bad luck on people; 3. Heaven is an entity that people revere and serve. Object; 4. Heaven is the existence that dominates people, especially the destiny of dynasties (the heaven of destiny); 5. Heaven is the existence that gives people the nature of benevolence, justice, propriety and wisdom. Another view is that "Heaven" is the representative of "Nature". "Unity of man and nature" has two meanings: First, it means that man and nature are unified. The universe is naturally a big world, while humans are a small world. The second is the correspondence between heaven and man, or the communication between heaven and man. It means that man and nature are essentially connected, so all human affairs should comply with the laws of nature to achieve harmony between man and nature. Laozi said: "Man follows the earth, the earth follows the sky, heaven follows the Tao, and the Tao follows nature." (The second copy of "Laozi" unearthed in Mawangdui) shows the consistency and interconnection between man and nature. Pre-Qin Confucianism also advocated "the unity of nature and man". "Book of Rites: Doctrine of the Mean" said: "Sincerity is the way of heaven, and sincerity is the way of man." It is believed that as long as people carry forward the virtue of "sincerity", they can be consistent with heaven. Dong Zhongshu, a Han Confucian, clearly stated: "Heaven and man are integrated into one." ("Spring and Autumn Fanlu: Deep Observation of Names") has become an important point of Confucian thought for two thousand years.
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