The Mind Faculty Cannot Merely Perceive Significant Dharma Objects

Question: Some say: "The mental faculty is like the edge of a sword, which cannot cut itself. This refers to the seventh consciousness, the mental faculty, also known as the manas consciousness. The Buddha stated that this seventh consciousness is called the mental faculty because it serves as the dynamic force for the manifestation of the seeds of the sixth consciousness (mano-vijñāna) from the eighth consciousness (ālaya-vijñāna). The sixth consciousness relies on the mental attention (manaskāra) of the manas consciousness to manifest, and after manifestation, it operates entirely according to the mental attention of the mental faculty, the manas consciousness. Hence, it is said that the manas consciousness is the root of the sixth consciousness. The particular discernment (pratiniyata-prajñā) of this mental faculty is extremely inferior; it can only perform very simple discernment on the mental objects (dharmas) arising from the five sense objects (rūpa, śabda, gandha, rasa, sparśa)—for example, whether there are major changes in the mental objects arising from the five sense objects? This seventh consciousness is not like the perceiving mind of the sixth consciousness, which can function adeptly with the five particular mental factors (pratiniyata-caitta): desire (chanda), conviction (adhimokṣa), mindfulness (smṛti), concentration (samādhi), and discernment (prajñā). It lacks the mental factors of desire, conviction, mindfulness, and concentration, and its function of discernment (the particular discernment) is also extremely inferior, capable only of performing very simple discernment regarding changes in mental objects.

Thus, being unable to discern even the five sense objects, it must arouse the sixth consciousness, and only then, relying on the particular discernment of the sixth consciousness, can it engage in various contemplations regarding all phenomena. How then could it have the ability to introspect itself? How could it have the ability to contemplate all dharmas? How could it have the ability to correct its own mental conduct and habits? Therefore, although this seventh consciousness is extremely adroit and can pervade all dharmas, and can further rely on the particular discernment of the sixth consciousness to act as the master everywhere and at all times, and can contemplate and determine various mental activities; yet, if separated from the particular discernment of the sixth consciousness, it becomes incapable of any action. Due to this nature, the Buddha said that the mental faculty (the manas consciousness) is like the sharp edge of a sword (metaphor for its adroitness in pervading all dharmas. Although the sixth consciousness possesses particular discernment, it cannot pervade all dharmas) yet cannot cut itself (metaphor for its lack of the 'self-verifying aspect' (svasaṃvitti) of particular discernment, hence it cannot correct its own wholesome or unwholesome mental conduct); meaning that for this consciousness 'to change its defiled nature, to transform into a pure mental faculty,' it must rely on the particular discernment and contemplative wisdom of the sixth consciousness to effect any transformation. It cannot eliminate its own corresponding afflictions solely by its own function. Hence, the Buddha said the mental faculty is like the edge of a sword, which cannot cut itself."
The above passage feels somehow incorrect. Could you analyze and explain it?

Answer: The claim that the mental faculty only discerns significant mental objects contradicts the Buddha's teaching that the mental faculty silently contains all dharmas. Since the mental faculty can pervade all dharmas, it can grasp any dharma; there is nothing it cannot grasp. Yet the above text states that the mental faculty only grasps mental objects arising from the five sense objects, and moreover only significant or changing ones, imposing so many limitations. If the mental faculty has so many dharmas it cannot grasp, this contradicts the Buddha's principle that the mental faculty pervades all dharmas.

For example, when observing the sun, one may observe it for an hour, or even half a day or a full day. The sun does not change significantly within an hour. Why then can the sixth consciousness continue observing it? Does the mental faculty not grasp the unchanging sun? Whatever dharmas the mental faculty grasps, the sixth consciousness is qualified to discern them. What the sixth consciousness knows, what the six consciousnesses discern, are all dharmas that the mental faculty has decided to grasp and discern. How could the mental faculty grasp only mental objects arising from the five sense objects, and moreover only significant or changing ones? The Śūraṅgama Sūtra states that the mental faculty silently contains all dharmas. If the mental faculty could not grasp subtle and minute objects of the six sense fields, it would not be silently containing all dharmas. In that case, the six consciousnesses would never know subtle and minute objects of the six sense fields.

If the mental faculty lacked desire and did not wish to act, the six consciousnesses would not arise, and no phenomena would appear. When the eye consciousness selects purple from a multitude of colors, it is decided by the mental faculty. This shows that the mental faculty also grasps objects of the five sense fields, enabling it to act as the master directing the six consciousnesses to discern those objects. If the mental faculty did not grasp or contact objects of the five sense fields, the five sense consciousnesses would not arise to discern them, and there would be no selectivity regarding the five sense objects. If there were dharmas the mental faculty could not grasp, it would not be pervading all dharmas.

If the mental faculty lacked conviction (adhimokṣa), always being muddled, it could not act as the master, nor could it perform correct, reasonable, true, and dharmic actions. It could not avoid dangers, nor transform consciousness into wisdom. If the mental faculty lacked mindfulness (smṛti), it could not cause the sixth consciousness to manifest mindfulness. No phenomena would appear; one could not recite the Buddha's name nor engage in Chan meditation. No phenomena would arise. If the mental faculty could not contemplate, the sixth consciousness's influence on the mental faculty would be meaningless, and it certainly could not transform consciousness into wisdom. No wisdom would appear. If the mental faculty lacked concentration (samādhi), no matter how the six consciousnesses cultivated concentration, they could not achieve it.

If the mental faculty could not correct wholesome and unwholesome mental conduct, then mental conduct could never be changed. Evil would remain evil forever. How then could one subdue afflictions and eradicate them? The sixth consciousness's influence on the mental faculty would yield no results, rendering the effort futile. The above passage states that the mental faculty lacks introspective power and lacks the self-verifying aspect (svasaṃvitti), yet the Buddha said all eight consciousnesses possess the self-verifying aspect. Sentient beings trust themselves so much, being extremely stubborn—this is the functioning of the mental faculty's self-verifying aspect. Being utterly obstinate and unwavering in belief is the mental faculty's self-verifying aspect; it simply believes itself to be right.

The mental faculty has the function of constant examination and contemplation. All dharmas must undergo its examination and approval before they can pass and decisions can be made. If the mental faculty's discernment were always so inferior, how could it reasonably examine and approve, how could it make wise decisions? If it could not make wise decisions, sentient beings' bodily, verbal, and mental actions would constantly exhibit foolishness and lack of wisdom. How then could intelligent people exist in the world? How could one attain wisdom and become a Buddha through practicing Buddhism? Furthermore, if the mental faculty contemplates, it should rely on its own inherent wisdom to contemplate. How could it rely on the particular discernment of the sixth consciousness to contemplate? This claim is too strange. It is like saying person A must rely on person B's wisdom to think, borrowing person B's brain. This does not conform to even a little logic. The above passage contains too many errors. I will analyze it in detail when time permits.