How Do Dreams Arise? How Many Consciousnesses Are There in Dreams?

Dreams arise from the manas' grasping and attachment to things one has experienced and things one has not experienced; the tathāgatagarbha, complying with that grasping, manifests the dream. The manas' grasping and attachment belong to the manas' imputed nature (parikalpita-svabhāva). All the mental activities of the manas are known by the tathāgatagarbha; after knowing them, it complies with the manas' mental intentions and the karmic force of sentient beings, manifesting the dream, allowing sentient beings to continue grasping and attaching within the dream. If the manas does not grasp and attach, the tathāgatagarbha will not actively manifest a dream.

Therefore, after some people's cultivation gains strength, their dreams gradually change from turbid to pure, and from many dreams to few dreams. This is because their cultivation has penetrated deep into the manas; after being perfumed, the manas' ignorance diminishes and its attachment decreases. The arhats' manas, having completely severed the afflictions of self-grasping and eliminated attachment to worldly dharmas, rarely has dreams appear.

Within a dream, three consciousnesses—the sixth consciousness, the seventh consciousness, and the eighth consciousness—are actively operating; the first five consciousnesses are not present. Therefore, the images in dreams are very hazy, unlike when awake. When awake, the five sense-object realms are all clear and distinct, whereas in dreams the five sense-object realms are not clear and distinct. Although after waking one feels that the eyes also saw material sense-objects, one cannot see the colors of people and things. Although one can sense colors, sense spaciousness, and sense brightness and darkness, that is only the mind consciousness's sensing, not the eye consciousness truly seeing these scenes. The realms seen in dreams differ greatly from those seen when awake.

For example, seeing people from past lives, or seeing people from other worlds—these cannot be seen by the eye consciousness. The eye consciousness absolutely cannot see people from past lives or from other worlds; otherwise, all sentient beings would possess the divine eye. Without supernatural powers and the divine eye, the eye consciousness cannot see people and things of past lives, cannot see people and things of future lives, and cannot see people and things of other worlds. If the eye consciousness could see them, the eye faculty would be able to face those material sense-objects; in fact, the eye faculty cannot face those material sense-objects and cannot condition those material sense-objects. Otherwise, the eye faculty could go to past lives and other worlds, and the body faculty could also go to other worlds; in fact, the body is still sleeping in bed and has gone nowhere.

A dream is a solitary realm, a mental sense-object realm manifested by the tathāgatagarbha directly transmitting seeds; only the manas and the sixth consciousness can condition it, and the one that can truly clearly discern it is only the sixth consciousness. The eighth consciousness transmits karmic seeds and manifests the mental sense-object realm in the dream because the manas has the nature of grasping and attachment; the manas grasps, the eighth consciousness complies, and thus the dream is manifested. "What one thinks of by day, one dreams of by night" illustrates this principle: precisely because of what the manas' deliberation (manasikāra) thinks and contemplates, the eighth consciousness manifests the dream.