Knowing and Seeing Without Seeing: This Is Nirvāṇa

There is a saying in the Śūraṅgama Sūtra: 知见立知，即无明本；知见无见，斯即涅槃。"知见立知，即无明本" means that all sentient beings possess a mind of seeing, hearing, awareness, and knowing, capable of seeing, hearing, being aware, and knowing. However, if we take these faculties of knowing as real, establishing the knowing faculty that knows the six sense objects as true, as an everlasting, imperishable self that can go on to future lives, then such a view is a wrong view/false view (mithyā-dṛṣṭi), the root of ignorance. In that case, one will transmigrate through the six realms of birth and death, unable to attain liberation.

"知见无见，斯即涅槃" — if, through contemplative practice (vipaśyanā-caryā), we come to understand that these faculties of seeing, hearing, awareness, and knowing are all deluded minds subject to arising, ceasing, and change, unable to abide permanently, unable to exist forever, and not the true self, then the mind will no longer take the faculties of seeing, hearing, awareness, and knowing as the self. Once such a view is firmly established, the view of self (satkāya-dṛṣṭi) is eradicated, and in the future one will be able to eradicate self-grasping and attain Nirvāṇa without remainder (Anupadhiśeṣa-nirvāṇa). If, upon the faculties of seeing, hearing, awareness, and knowing, one can realize that intrinsically pure mind which itself possesses no faculty of seeing, hearing, awareness, or knowing, then one has realized the originally pure nirvāṇa of self-nature.

To explain this saying more precisely: "知见无见" means that, alongside the various views and knowings of the six consciousnesses, there is simultaneously a fundamental mind, the tathāgatagarbha, which has no views or knowings whatsoever, and which has been operating behind the scenes all along; "斯即涅槃" — He is the unborn and unceasing fundamental mind, the tathāgatagarbha, within the state of nirvāṇa, that is, the mind of nirvāṇa.