Is the Manas Really a Case of Non-Valid Cognition?

It depends on what the definition of erroneous cognition (non-valid cognition) is. If wrong views, wrong understanding, and wrong grasping are defined as erroneous cognition, then the manas is erroneous cognition, and at the same time all six consciousnesses are also erroneous cognition, because all of them have wrong views and wrong understanding. If imagination, fantasy, supposition, and the like are erroneous cognition, then the manas is not erroneous cognition at all; it is entirely direct perception. If the manas could have the kind of erroneous cognition that the mind consciousness has, learning Buddhism and practicing would be much easier, living in worldly dharmas would be much easier, and upon encountering the Buddha-dharma one would easily understand it correctly; there would be no need to laboriously cultivate meditative concentration, investigate Chan, engage in contemplative inquiry, or practice contemplative practice (vipaśyanā-caryā), and attaining buddhahood would not require three great asaṃkhyeya kalpas. As for why it takes such a long time to cultivate and become a Buddha, it is precisely because the manas lacks sufficient wisdom and needs long-term permeation—presenting facts and reasoning things out.

If the definition of erroneous cognition is having wrong views and wrong understanding of all dharmas, then the manas is indeed erroneous cognition, because of ignorance: toward all dharmas He has wrong views and wrong understanding, even to the point of wrong grasping. Therefore, learning Buddhism and practicing is precisely to break through the manas's ignorance and to correct all of the manas's wrong views and wrong understanding. When ignorance is completely severed and everything becomes correct understanding, and all wrong grasping is also completely severed, sentient beings attain buddhahood.

Correcting the manas's wrong understanding depends on the mind consciousness's correct understanding. For the mind consciousness to have correct understanding, it must study the Buddhist sutras, deeply and correctly comprehend them, and then engage in right contemplation, permeating the manas, so that the manas follows and accords with the mind consciousness's correct understanding and deliberates rightly (manana), thereby endowing the manas with correct understanding and right view, rectifying its former wrong knowledge, wrong understanding, and wrong actions. Thus, the manas's ignorance that must first be broken through is the manas's self-view (ātma-dṛṣṭi); only afterward can the manas's self-grasping be completely severed.

The manas's ignorance that must next be broken through is to make Him recognize the eighth consciousness as the master of the dharma-realm, rather than Himself. Only afterward can the manas's grasping of dharmas be completely severed. When the grasping of dharmas is completely severed, sentient beings attain buddhahood.

Therefore, from beginning to end, learning Buddhism is all about cultivating the manas, with the aim of eliminating and completely severing the manas's ignorance, fully returning to self-nature, and no longer being inverted. In this process, the guidance of the mind consciousness is needed. Therefore, the mind consciousness must first break through ignorance and inverted views before it can guide the manas onto the correct path toward liberation, ultimately achieving complete and thorough great liberation. Hence, cultivating the manas is the true cultivation; cultivating only the mind consciousness, without knowing which is master and which is servant, is an inverted view—the cultivation will fall short, and liberation cannot be attained.