戴震在其主要著作《孟子字義疏證》中以氣學的進路重構了儒學，也改寫了孟子的身體觀。氣學進路的儒學重構預設了自然主義一元論的立場（理氣一本、性才同源），藉此反對程朱理氣二分的形上架構。戴震主張規範的必然性就在自然之中，他批評程朱「離人而空論夫理」，反對從超越而同一的理來說明規範的基礎。氣化的身體對戴震而言並非與精神相對反的概念，就像欲望未必與理性相對；氣化的身體本具必然的理則，欲望的合理表現便是理性。

Dai Zhen(戴震) reconstructs Confucianism with the approach of Qi(氣), in which Meng Zi’s(孟子) idea of body is renewed. His Qi-approach presupposes holistic naturalism, where Li(理) and Qi(氣) are inseparable, and deconstructs the metaphysical dichotomy in Neo-Confucianism of Cheng Yi(程頤) and Zhu Xi(朱熹). The notion of Li in Dai Zhen’s interpretation of Pre-Qin Confucianism is different from that in Cheng Yi and Zhu Xi, which represents a norm beyond human being. Dai Zhen claims that the necessity of norm is intrinsic to Nature; Li must not be detached from desire(欲). For Dai Zhen, Qi-body is not a concept opposed to spirit; in the same fashion desire is not against reason. Necessary principle exists in Qi-body by nature; hence the reasonable desire is just the reason itself.