The Supreme Vacuity which neither comes into [nor goes out of] existence is probably the subtle principle in the reflection of the mysterious mirror of prajna (wisdom) and the source of all existence. Unless one possesses the intelligence and special penetrating power of a sage, how can he harmonize his spirit with the realm of neither existence nor nonexistence? Therefore the perfect man penetrates the infinite with his wonderful mind and the finite cannot obstruct him. He applies to the utmost his ears to listen and his eyes to see, and sound and color cannot restrict him. Is this not because he leaves the vacuous self-nature of things as it is and therefore they cannot affect his spiritual intelligence? Therefore the sage exercises his true mind and is in accord with principle (li), and there is no obstruction which he cannot pass through. He views the transformation of all things with the clear understanding that [they are all of] one material force (1) and therefore he is in accord with whatever he may encounter. Since there is no obstruction which he cannot pass through, therefore he can mix with the impure and achieve purity, and since he is in accord with whatever he encounters, he sees the unity of things as he comes in contact with them. Since this is the case, although the ten thousand forms (phenomenal things) seem to be different, they are not so in themselves. As they are not different in themselves, it follows that these [apparent] forms are not the real forms. As these forms are not the real forms, although they [appear to be] forms, they are not [real] forms at all.

(Seng-Chao)