Which is born first: the eye consciousness or the mind consciousness?

Observe: when you look but do not see, do you know there is light before your eyes? If you know there is light before your eyes, then the eye consciousness has discerned it, and the mind consciousness has discerned it very faintly. Because the mind consciousness must divert part of its attention—or most of its attention—to think about other important matters, its discernment is very faint, and only then does the phenomenon of looking without seeing occur. Observe: when seeing form, is it the case that one first knows there is light, there are images, and only then can one know the fine details of objects? If so, this shows that the eye consciousness arises first and the mind consciousness afterward. Without direct perception (valid direct cognition), with poor meditative concentration, and with erroneous theory on top of that, no matter what, one cannot arrive at the correct conclusion.

At the very beginning of discerning a certain dharma, the question arises of whether the five sense consciousnesses arise first or the mind consciousness arises first; once all have arisen, the question of which consciousness arises first no longer applies. When you close your eyes and then open them again, the question of whether the eye consciousness or the mind consciousness arises first comes into play. Even with your eyes closed, through the eyelids, you can still sense there is light—that means the eye consciousness has not ceased and can still discern visible form; the eye consciousness only discerns visible form, the colors on material sense-objects, as described in Volume One of the Yogācārabhūmi-śāstra.

What the five sense consciousnesses discern is the relatively coarse part of material form—the four great elements' subtle particles that the tathāgatagarbha, based on the outer five sense-objects, extracts from the outer five sense-objects and transmits into the supreme faculty at the back of the brain, where they are manifested. This is close to the essential nature of the outer five sense-objects that the tathāgatagarbha contacts and discerns. The eye consciousness needs to make fresh mental engagement only at the beginning of seeing form. For example, there are many things in a room; when the eye consciousness shifts from one place to another and the objects seen change, the eye consciousness must make fresh mental engagement, and the mind consciousness must also make fresh mental engagement. So whenever the form seen changes, the question of the arising of the eye consciousness and mind consciousness is involved. But in every case, the eye consciousness arises first, and a moment later the mind consciousness arises. When seeing form, the eye consciousness first sees hazy, indistinct colors—whether it is empty or whether there is an object—and the mind consciousness afterward sees the shape, size, length, shortness, squareness, roundness, content, and meaning, and so on. However, upon waking from sleep, it is certainly the solitary mental consciousness transforming into the mental consciousness accompanying the five sense consciousnesses that arises first, and then the five sense consciousnesses arise afterward—the order is the reverse of that when one is awake.

Whatever belongs to the coarse part—vague, hazy, and indistinct—is the content discerned first by the five sense consciousnesses; the fine content is discerned afterward by the mind consciousness. The connection between the five sense consciousnesses and the mind consciousness is extremely fast; a person without meditative concentration (dhyāna) simply cannot distinguish it. Therefore, many people, even when told these contents, still cannot carry out contemplative practice (vipaśyanā-caryā) on them and cannot realize them; they can only recite other people's theories. Each time the six consciousnesses see a form of material dharma, they must make fresh mental engagement; the manas must first make fresh mental engagement even more so—only through continual mental engagement can it guide the six consciousnesses to engage mentally and discern. These subtle dharmas simply cannot be brought forth in contemplative practice without meditative concentration.

Hearing sounds is the mind consciousness and ear consciousness hearing together; the ear consciousness alone cannot hear sounds. When sitting in meditation and suddenly hearing a sound, the ear consciousness arises first to discern, and the mind consciousness discerns afterward; the ear faculty first senses the vibration, and only afterward does the mind consciousness know what the sound is. When the ear consciousness hears a sound, first there is a vibrational sound transmitted to the ear faculty, vibrating the eardrum—this is the coarse sound discerned by the ear consciousness; afterward the mind consciousness discerns the fine content such as the sound's pitch, distance, loudness, and meaning. This shows that the ear consciousness discerns before the mind consciousness and arises before the mind consciousness.