The mental factor of volition (cetanā) of the manas determines the discernment of the eye consciousness and the mind consciousness

When the eye consciousness sees form, what it sees are manifest forms (rūpa): blue, yellow, red, white, light and darkness, clouds, mist, haze, and space. Light is a kind of material substance, composed of the four great elements, arising and ceasing, changing moment by moment; it is false and unreal.

The eye consciousness itself possesses the mental factor of volition (cetanā). After receiving the form sense-object, it cognizes the form sense-object, and then the mental factor of volition arises, deciding to act—whether to avoid it or to look at it a while longer. The eye consciousness works in close cooperation simultaneously with the manas and the mind consciousness. Without the manas's attention (manaskāra) and the mental factor of volition, there would be no arising of the eye consciousness and the mind consciousness, and no cognition by them; there would be no operation of the five universal mental factors of the eye consciousness, nor would the five universal mental factors of the mind consciousness appear. When the eye consciousness sees form, the seventh consciousness cannot see form; when the mind consciousness analyzes, infers, and judges, the seventh consciousness cannot infer or analyze. Only when a consciousness has the nature of discrimination, cognition, and recognition is it called a consciousness; otherwise it is not called a consciousness. All seven consciousnesses possess the nature of cognition, discrimination, and recognition.

Do the first five consciousnesses have the function of deliberation?

The first five consciousnesses also have the five universal mental factors: attention (manaskāra), contact (sparśa), feeling (vedanā), perception (saṃjñā), and volition (cetanā); it is just that theirs are simpler and coarser than the five universal mental factors of the sixth and seventh consciousnesses. The sixth and seventh consciousnesses deliberate upon mental sense-objects (dharma-viṣaya), and their deliberation can be very subtle and profound; the first five consciousnesses deliberate upon the five sense-objects, and their deliberation is very coarse and simple. As long as one can separate the five sense-objects from the mental sense-objects and not confuse them, one can distinguish the difference between the volition of the five consciousnesses and the volition of the sixth and seventh consciousnesses. The volition of the five consciousnesses is not the kind of deliberative function that the mind consciousness has; the two are different, and the difference is considerable. Separating the five sense-objects from the mental sense-objects is extremely difficult, so distinguishing the cognition of the five consciousnesses from that of the mind consciousness is also very difficult. Likewise, most people cannot distinguish the functions and roles of the manas from those of the mind consciousness.

What people ordinarily call deliberation generally refers to the sixth and seventh consciousnesses' deliberation upon mental sense-objects, especially the solitary consciousness's (mano-vijñāna-eka-citta) deliberation upon subjectively imagined realms; the five consciousnesses cannot but participate in it. The volition within the five universal mental factors of the five consciousnesses mainly serves the function of judgment and decision. After the five consciousnesses cognize their corresponding five sense-objects, they take the marks of those objects, make a simple, coarse judgment, and then decide whether to continue cognizing or to stop and avoid; the mind consciousness simultaneously participates in the cognition. The reason the five consciousnesses' cognition is said to be coarse is that the five sense-objects are gross and do not require fine discrimination; therefore the cognition is fast and does not require much mental effort from the five consciousnesses, as if it did not go through the brain at all. The mental sense-objects that accompany the five sense-objects, however, are relatively subtle and require the fine cognition of the mind consciousness; therefore the mind consciousness's cognition and analytical thinking are relatively slow and take more mental effort.

When the five sense-objects are major and their impact is great, the manas makes its decisions primarily following the judgments and decisions of the five consciousnesses, with no time to process the mind consciousness's analysis and judgment, and so it overlooks the mind consciousness's cognition and deliberation. Usually the five consciousnesses' cognition is rather direct and fast, while the mind consciousness's cognition is finer and slightly slower than that of the five consciousnesses. For major matters, the manas relies mainly on the reactions of the five consciousnesses and cannot attend to the mind consciousness's reactions. Therefore, in some sudden emergencies, the mind consciousness's analysis and deliberation are not used; the manas directs the matter to completion, causing the mind consciousness to be slow to realize what has happened. To sum up: deliberation refers to the deliberation of the sixth and seventh consciousnesses; the volition of the first five consciousnesses is simpler, coarser, and more direct than deliberation—not deep enough, and it does not need to be deep, because the five sense-objects and their dharmas are shallow, coarse, and direct.