俱舍論疏 1.191

1.191

論「善與不善名淨不淨」，此第三述無表性也。必假強表方能發故，不通無記。

The Śāstra says: "Wholesome and unwholesome are called pure and impure." This is the third section, which states the nature of the unmanifest. It must rely on a strong manifest action to be initiated, and therefore it does not extend to the indeterminate.