瑜伽師地論略纂 15.51

15.51

處非處善巧體，謂後得智得果因相，順處、相違非處智也。

The essence of skill in the possible and impossible (sthānāsthāna-kauśalya) is the posterior wisdom that apprehends the characteristics of causes and effects; it is the knowledge of what is conforming as possible, and what is contrary as impossible.