理學系統中是否有獨立的氣學一系，這是箇仍待討論的問題。本文從功夫論的角度入手，將近世儒學的氣論分成兩種，一種是先天類型，一種是後天類型。兩者都反對朱子學理氣二分的世界觀，也反對佛老的「空」、「無」之世界觀。但兩種「氣」的哲學基礎不同，先天類型的「氣」之概念等同於「體用論」中的「用」之概念（如羅欽順、張載），先天型氣論學者的工夫論主張逆覺以入「動靜一如」的流行之境，他們或從心學（心性論）的視野定位此先天型之氣（如劉宗周），或從道論（本體宇宙論）的角度定位此概念，其目的皆是要求得存在源頭之動能，返本以開個人與世界之新。後天型氣論的思想可定位為狹義的氣學，此氣學的氣是自然主義的用法，它反對超越性的內涵，所以其工夫主張乃落在氣的特殊性，用氣成性；也落在主張氣在此世的交感性，透過氣的共振建立意義交感的共同體；也透過心知的作用，納萬物之知為己性。先天型氣論的工夫仍是理學大傳統的「復性」模式，後天型氣學的主張則已走出理學的範圍，集中在經營氣質之性。前者是縱貫－溯源式的，後者則是橫拓－前進式的。前者是永恆不斷切入變化之流中的創新，後者的創新則是不斷與世交感的代換。兩者皆有「整體性」的倫理要求，但一來自超越的源頭，一來自血氣心知的內在目的性。

It is an unsolved problem that whether there's an independent philosophy of Ch'i in the system of Lixue. This article tries to divide the Ch'i philosophy into two modes--one is pre-created (transcendental, 先天), and the other is post-created (empirical, 後天). Both of them disapproved Zhu Xi's dichotomic worldview of Li and Ch'i and the "void" and "non-being" worldviews of Buddhism and Taoism; but they had dissimilar philosophic bases. The concept of Ch'i in the pre-created mode was equal to the "function" of "the theory of substance and function" (e.g. Lo Ch'in-shun, Chang Tsai); and these scholars advocated returning to the luminous realm of "Dong Jing Yi Ru" in order to obtain the dynamic energy from the source of Primordial Creation and to renew the individual and the world. They orientated the pre-created Ch'i either from the viewpoint of the doctrine of Mind (e.g. Liu Tsung-chou) or from the aspect of onto-cosmology (e.g. Chang Tsai). The one of the post-created mode can be defined as the narrow or standard Ch'i theory, which belonged the the usage of naturalism and objected to transcendence, therefore, it stressed the specially and the earthly sympathy of Ch'i. By the unique quality of Ch'i spreading in everybody, everyone should develop his or her unique personality. By the sympathetic quality of Ch'i, everyone should cultivate the feeling of unity with others. The cultivation of the pre-created Ch'i theory still belonged to the mode of "the recovery of the Nature" of the tradition of Lixue; however, the cultivation of the post-created one had gone beyond the limit of Lixue. The former mode is vertical-regressive, and the later one is horizontal-progressive.