起信論疏筆削記 13.30

13.30

"These three..." and so forth: Someone might ask: "Among these four meanings, why are three fully explained for defilement, while only one is explained for purity?" Now this is explained. Because defiled dharmas are by their original nature differentiated, and can arise only by relying on causes and depending on conditions, three meanings must be explained. Although the single flavor of pure dharmas is divided into essence and function, the function is still identical with the essence and has no difference. "Relying on and depending on causes and conditions": among these three, avidyā is the cause, deluded objects are the conditions, and the deluded mind is that which arises from causes and conditions. The fundamental consciousness and the worldly consciousness each have their causes and conditions, as broadly distinguished earlier. "Essence and function have no difference": internal perfuming is simply the essence, and external perfuming is the function. When function unites with essence, it does not come from outside separately; they fuse into a single flavor. Therefore, the Buddha within the mind of sentient beings turns back to transform sentient beings themselves; hence only one kind is spoken of.