首楞嚴義疏注經 2.568

2.568

若見明時不與明合，明、見二性應相乖異。如牛之角敵對各立，曾不相應。亦如耳根對於明緣，何曾相觸？耳但聞聲，不緣明故。若以此例，見須不知明相所在，若無明相亦不顯見。明見既無，如何分別合與非合二種義耶？

If when seeing light it does not join with light, the two natures of light and seeing should be completely divergent. Like the horns of an ox, they would stand opposed to each other and never correspond. It would also be like the ear faculty confronting the condition of light—how could they ever make contact? The ear only hears sounds and does not condition light. If analogized by this, seeing must not know where the appearance of light is; and if there were no appearance of light, seeing would not be manifested either. Since neither light nor seeing would exist, how could one distinguish the two meanings of joining and not joining?