Not understanding the six sense bases does not mean not discerning the six sense bases (ṣaḍāyatana)

The Buddha, in the Vimalakīrti Nirdeśa Sūtra, spoke of the eighth consciousness as the bodhi mind: "the sense bases do not engage with it"—that which does not engage is bodhi. Does "not engaging with the six sense bases" mean not discriminating the six sense bases? Who received the Fifth Patriarch's robe and bowl? The one who did not engage with the Buddha-dharma received it. What does this "not engaging" mean? It means not understanding or knowing the specific contents of the Buddha-dharma—this refers to the eighth consciousness, the bodhi mind.

The six sense bases (ṣaḍāyatana) include the eye base, ear base, nose base, tongue base, body base, and mind base, encompassing the outer six sense bases—form, sound, smell, taste, touch, and dharma—and the inner six sense bases: the eye supreme faculty, ear supreme faculty, nose supreme faculty, tongue supreme faculty, body supreme faculty, and the manas. The six consciousnesses, which arise in dependence upon the outer and inner six sense bases, both know and understand the six sense faculties, and also know and understand the six sense objects. But the eighth consciousness, the bodhi mind, neither knows nor understands what the six sense faculties are, and neither knows nor understands what the six sense objects are.

The eighth consciousness has no ignorance; it can condition all dharmas—attention (manaskāra), contact (sparśa), feeling (vedanā), perception (saṃjñā), and volition (cetanā) toward all dharmas—and thus it can know all dharmas as they truly are and understand all dharmas. If the eighth consciousness did not know or understand all dharmas, did not know or understand the six sense faculties and six sense objects, then how could it grasp and sustain the six sense faculties and six sense objects at every moment, instant by instant, second by second, and transform the six sense faculties and six sense objects? The eighth consciousness also engages in feeling, perception, and volition toward the six sense faculties and six sense objects, making choices and carrying out subsequent actions; it must therefore know and understand the six sense faculties and six sense objects, and that is precisely why it necessarily knows how to act. It is only that the eighth consciousness does not know the worldly dharma-marks of the six sense faculties and six sense objects, and does not know their worldly contents—these are the contents known by the seven consciousnesses. Then what does the eighth consciousness know? Without profound seed-wisdom of Consciousness-Only (唯识种智), one cannot observe what the eighth consciousness knows; one would have to ask the eighth consciousness itself. The eighth consciousness has no ignorance; it discriminates all dharmas with perfect clarity, without the slightest error or confusion—unlike the seven consciousnesses, which in many cases discriminate unclearly, resulting in confused choices, confused actions, and confused karmic retribution.