牟宗三提出的「化境」，作為一個美學範疇，值得引起特別的重視。「化境」以「善」為基石，以「即真即美即善」（合一說）為內涵，具有無相之相的特色，即真無真相、美無美相、善無善相。牟宗三的理論與王國維和馮友蘭的學說並不相同，「化境」是藝術（美學）的，但又不限於藝術（美學），而王國維「境界」主要是藝術（美學）的；「化境」是人生的，但又不限於人生，而馮友蘭的「人生境界」則主要是人生的。「化境」是人生與藝術的合一，是對王國維「境界」和馮友蘭「人生境界」之理論的發展和提升。

Mou Chung-san’s “the realm of unity”, as an aesthetic category, deserves special attention. “the realm of unity” takes “goodness” as the cornerstone, and “truth is beauty is goodness”(unity category) as the connotation. It has the characteristics of no image, that is, truth is no truth image, beauty is no beauty image, and goodness is no goodness image. The theory of Mou Chung-san is not the same as that of Wang guo-wei and Feng you-lan. “The realm of unity” is artistic (aesthetic), but it is not limited to art (aesthetic), while Wang Guo-wei’s “realm” is mainly artistic (aesthetic); “the realm of unity” is life, but it is not limited to life, while Feng You-lan’s “realm of life” is mainly life. “The realm of unity” is the unity of life and art, and it is the development and promotion of Wang Guo-wei’s “realm” and Feng You-lan’s “realm of life” theory.