Zhang Zai's main contribution to philosophy is that he first put forward a more detailed theory of qi from the perspective of natural view and established a systematic theory of qi. Qi is the basic concept of China's ancient materialism. Taoism in the pre-Qin period once put forward the view that "one ear can communicate with the whole world". Wang Chong creatively put forward the materialistic theory of natural vitality in Han Dynasty, which came to an end after Fan Zhen, Liu Zongyuan and Liu Yuxi. In the Wei, Jin, Sui and Tang Dynasties, metaphysics and Buddhism put forward idealism ontology to counter the vitality naturalism of materialism. Metaphysics, represented by Wang Bi, highly praised Laozi's "making something out of nothing" and vigorously demonstrated "making something out of nothing". Buddhism also takes truth as its nature or heart. They all try to find a spiritual ontology that dominates the universe outside, above and after the phenomenal world, and regard it as the highest source of the universe. In this context, Zhang Zai founded the ontology of vitality, which holds that the ontology of the universe is not spirit, but material qi. He also used it as a weapon to criticize the idealism fallacy of Taoism and Buddhism, and initially demonstrated that the unity of the world lies in the principle of materiality. He also affirmed that Qi changes in movement, and the root of movement changes lies in the inherent contradictions contained in Qi itself, thus preliminarily demonstrating the internal relationship between matter and movement. Taihe Pian embodies these exquisite thoughts of Zhang Zai and occupies a very important position in Zhengmeng.