牟宗三主張「美是氣化之多餘的光彩」，其含義為，美是宇宙中陰陽之氣生化的、無概念無利害的、萬物一體之生命由內而外所放出的光彩。簡言之，美就是即真即善的光彩，它可以在智的直覺中朗現。牟宗三的這種學說，是在孟子「充實而有光輝」之思想的基礎上，對康德與海德格爾之理論所進行的超越。康德把美視為真與善之橋樑，而海德格爾則把美視為真的顯露。牟宗三所定義的美，是站在儒家真善美合一之化境的前提下所分別說中的美，具有濃厚的道德的形而上學的色彩。這體現了牟宗三復興儒學、實現圓教的宏願。

Mou Zongsan held that “beauty is the superfluous brilliance of gasification”, which means that beauty is the brilliance of the Yin and Yang Qi in the universe. In short, beauty is the brilliance of truth and goodness, which can be seen in the intuition of wisdom. On the basis of Mencius’s thought of “brilliance of fullness”, Mou Zongsan’s theory transcended the theories of Immanuel Kant and Martin Heidegger. Immanuel Kant saw beauty as a bridge between truth and good, while Martin Heidegger saw beauty as the manifestation of truth. Mou Zongsan’s definition of beauty was the separate beauty, based on the Confucian realm of unity of truth, goodness and beauty, with a strong moral metaphysics color. This embodies Mou Zongsan’s grand wish to revive confucianism and realize Yuan Religion.