首楞嚴義疏注經 2.88

2.88

Question: The first five unconditioned dharmas are conventional in both name and substance; like the previous dharmas, they are devoid of substance, like shadows. The unconditioned dharma of tathatā is conventional in name but real in substance, serving as the nature of all dharmas; why say it is devoid of substance like an image? Answer: The tathatā spoken of in this school is still established in opposition to delusion. Since it is due to mutual opposition, it still constitutes a delusive dharma. As the sūtra below says: 'Speaking of delusion reveals all truths; delusion and truth are equally two delusions.' It also says: 'The unconditioned has no arising or ceasing; unreal, like flowers in space.' The Sūtra of Perfect Enlightenment says: 'From perfect enlightenment flow forth all pure tathatā, bodhi, nirvāṇa, and so forth.' Therefore, the dharmas of the five categories are only manifestations of the mind, and all are identical to images.