A Brief Discourse on the Essence of Consciousness

Chapter One: Types of Consciousness

Consciousness, also known as the sixth consciousness, has the intrinsic nature of differentiating and discerning the realms of dharma dust (objects of mental perception). It encompasses mental activities such as thinking, analyzing, reasoning, judging, recollecting, making vows, planning, delusional thinking, investigating, and so forth, exhibiting three natures: wholesome, unwholesome, and neutral (non-wholesome, non-unwholesome, and non-recordable). Consciousness exists in two forms: five-concomitant consciousness and solitary consciousness.

Five-Concomitant Consciousness: This consciousness arises simultaneously with the first five consciousnesses and jointly differentiates the six dusts (objects of the senses) alongside them. For example, when the eye perceives form, the eye consciousness differentiates the coarse aspects of form dust, such as color, brightness, darkness, haze, and emptiness or non-emptiness (manifest colors). The conscious mind, however, differentiates the subtle aspects of the form dust, such as quality, category, connotation, weight, gender, beauty or ugliness, goodness or evil, cultivation, charm, shape, surface color, and non-surface color. When the ear hears sound, the ear consciousness differentiates the coarse aspects of sound, such as vibrations, frequency, amplitude, etc., while the conscious mind differentiates the subtle aspects, such as pitch, distance, coarseness or fineness, the connotation, meaning, category, origin, wholesome or unwholesome nature, goodness or badness, male or female voice, charm, etc., manifested on the sound dust. The conscious mind similarly differentiates simultaneously with the nose consciousness, tongue consciousness, and body consciousness—that is, it differentiates alongside the five consciousnesses. Hence, it is called five-concomitant consciousness.

Solitary Consciousness: This consciousness does not differentiate the five dusts together with the five consciousnesses. Instead, it functions alone to differentiate and discern dharma dust, recollecting the past, envisioning the future, engaging in delusional thinking, discerning meditative states, dream states, and other solitary-shadow realms. This is solitary consciousness. Solitary consciousness is further divided into scattered solitary consciousness, meditative solitary consciousness, dream solitary consciousness, and deranged solitary consciousness.

II. The Functional Nature of Consciousness

The functional nature of consciousness is to engage in a series of mental activities such as pondering, analyzing, reasoning, judging, deliberating, and making choices regarding the realm of dharma dust. The arising of consciousness occurs because the mental faculty (manas) relies on dharma dust, attends to dharma dust, and discerns dharma dust, after which it resolves to discern dharma dust in detail. The Tathāgatagarbha (Buddha-nature) then gives rise to consciousness to perform subtle discernment, enabling the mental faculty to know the subtle dust realms through consciousness. When the mental faculty relies on dharma dust, the Tathāgatagarbha gives rise to consciousness. Once consciousness arises, mental activities such as analysis, thinking, reasoning, and judgment come into being.

Where do the dharma dust realms analyzed and deliberated by consciousness come from? Their source is the Tathāgatagarbha, which manifests them as illusory phenomena based on conditions. Whether the dharma dust corresponding to and discerned by consciousness is associated with the first five dusts or not depends on whether this dharma dust is related to the five dusts, whether it is a subtle aspect of the five dusts, and whether the discernment of the conscious mind requires the five consciousnesses as supporting conditions. If the dharma dust is unrelated to the five dusts, it is a solitary-shadow realm—dharma dust discerned by solitary consciousness. If discernment does not require the five consciousnesses, it is solitary consciousness; if discernment cannot occur alone without the cooperation of the five consciousnesses, it is five-concomitant consciousness.

If the conscious mind is five-concomitant consciousness, it must differentiate simultaneously alongside the first five consciousnesses. The dharma dust corresponding to this conscious mind is necessarily form included in the dharma base (dharmāyatana) that is associated with the five dusts of form, sound, smell, taste, and touch—it is related to the five dusts. This means the Tathāgatagarbha transforms the external six dusts through the six sense faculties into the subtle sense faculties (indriyas), thereby manifesting the internal six dusts. When the faculties and dusts make contact, consciousness and the first five consciousnesses arise together to differentiate the realms of the six dusts. Thus, the dharma dust discerned by consciousness is related to the first five dusts. Without the first five dusts, this dharma dust would not exist, and the conscious mind could not arise. Therefore, this type of consciousness is called five-concomitant consciousness.

III. Solitary Consciousness

Solitary consciousness is further divided into scattered solitary consciousness, meditative solitary consciousness, dream solitary consciousness, and deranged solitary consciousness.

(I) Scattered Solitary Consciousness

Scattered solitary consciousness refers to when consciousness, while differentiating the dharma dust on the five dusts alongside the first five consciousnesses, is not focused. It simultaneously engages in solitary contemplation, delusional thinking, recollection, and discernment of other dharma dusts, leading to mental scattering. The mind cannot settle on a single object or stabilize on one realm; the mental waters become turbid, lacking concentration and wisdom, rendering it unable to clearly consider any matter. When the six consciousnesses differentiate the six dusts simultaneously, part of the conscious mind not only differentiates the six dusts alongside the five consciousnesses but also has its own scattered solitary realm, attending to other dharma dusts. The portion of dharma dust corresponding solely to consciousness is then unrelated to the first five dusts. It is dharma dust separately manifested by the Tathāgatagarbha—dharma dust directly output from the Tathāgatagarbha’s storehouse of seeds—a solitary-shadow realm discerned solely by the conscious mind.

For instance, while our eyes are observing a certain object, consciousness and eye consciousness are together discerning that object. Simultaneously, consciousness attends to other matters and is not focused on observing and discerning the present object. At this moment, the attention of the conscious mind is divided. It not only attends to the present matter alongside the eye consciousness but also contemplates other matters alone. This situation is a diversion of the seed-stream of consciousness, commonly called “lack of concentration” or “distraction.” When the conscious mind diverts, whichever aspect it leans toward is discerned more clearly because the seed-stream flows more abundantly there, resulting in stronger discernment power. If attention to the present object is weak, the seed-stream flowing to it is reduced, discernment power weakens, and the present object is discerned unclearly.

The diversion of the conscious mind’s attention is like the diversion of a river. If an originally powerful and swift current divides into several streams, the flow of each stream diminishes; with reduced flow, the force weakens, and its efficacy becomes feeble. If the conscious mind diverts, its attention scatters, resulting in unclear discernment in all aspects due to weakened power and diminished discernment capacity.

The attention of consciousness is a force, equivalent to the mental factor of attention (manaskāra) in consciousness. When consciousness attends to multiple realms, it simultaneously contacts multiple realms, receives multiple realms, and subsequently discerns multiple realms. Thus, the power of consciousness disperses, its efficacy becomes very weak, the force to discern each realm is feeble, discernment is unclear, and wisdom cannot arise. Therefore, without concentration, there is no meditative absorption (dhyāna); without meditative absorption, wisdom cannot arise.

Similarly, when listening to sound, if the conscious mind is not focused—i.e., attention is scattered—the connotation of the sound cannot be clearly heard, and its profound meaning remains unknown. When smelling fragrance, if consciousness is not focused and attention is scattered, the scent cannot be clearly distinguished, and discernment is neither meticulous nor thorough. When tasting, if the conscious mind is not focused and the mind is contemplating other matters, one experiences “eating without tasting.” When sensing touch, if consciousness is not focused and the mind is preoccupied with other thoughts, one remains unaware of bodily conditions; even if bitten by a mosquito or experiencing bodily abnormalities, one is completely oblivious. If everyone could practice the Dharma with this mindset—showing no interest in the body, form, sound, smell, taste, or touch, forgetting everything around them—practicing the Dharma would yield great results.

When studying the Dharma, if consciousness focuses most of its attention on contemplating the Dharma and pays little heed to the other five dust realms, it naturally becomes oblivious to the five dust realms. At this time, the conscious mind is mostly attending to the content of Dharma practice and realization, enabling one to “forget the body.” This is also a form of concentration. What is most feared is when the conscious mind attends to multiple realms but is attentive to none, being utterly distracted like a “monkey mind”; the mind then remains unclear about anything, plunged into complete bewilderment.

Scattered solitary consciousness also includes another situation: when consciousness engages in solitary contemplation and discernment, it is still scattered. It does not contemplate a single principle exclusively but jumps around contemplating many dharmas. The mind is chaotic and disorganized, lacking coherence, resulting in an inability to clearly contemplate anything. Wisdom becomes very shallow or nonexistent.

(II) Meditative Solitary Consciousness

The dharma dust discerned by meditative solitary consciousness is directly manifested by the Tathāgatagarbha and is unrelated to the first five dusts—it does not coexist with them. The first five consciousnesses do not manifest; thus, the conscious mind alone discerns the dharma dust of the meditative state.

True concentration refers to the four dhyānas and eight samāpattis (absorptions). The concentration before the first dhyāna is the desire-realm concentration. Desire-realm concentration has six levels, corresponding to the six heavens of the desire realm. The more detached one is from human affairs, the deeper the level of concentration. The body becomes larger, sensations more free, lighter, and more comfortable. The highest heaven is the Paranirmitavaśavartin Heaven, closest to the first dhyāna heaven of the form realm. The concentration corresponding to it is called the “concentration not yet reached” (anāgamya-samādhi)—a concentration before reaching the first dhyāna stage, also divided into different levels, some complete and some incomplete. In desire-realm concentration, the five dusts are present, and the first five consciousnesses manifest. For example, opening the eyes allows one to see the scene before them; the ears can hear surrounding sounds. However, at this moment, the conscious mind is relatively focused, attending only to the object of meditation, or a certain sensation, or a specific thought, while other dust realms are faintly discerned.

For instance, when focused on contemplating and investigating the Dharma, investigating a critical phrase (huatou), the first five consciousnesses still exist. Because consciousness pays little attention to the five dusts, and the five consciousnesses’ own discerning power is relatively weak, their discernment is coarse. Although the first five consciousnesses exist, when there is dharma dust from a meditative state, it is consciousness alone that discerns it; the five consciousnesses do not participate. The five consciousnesses can still faintly discern the five dusts, and the conscious mind also participates in discernment, but discernment is relatively faint and unclear because consciousness is simultaneously attending to other dharma dusts, focusing its mind on contemplating other dharmas.

Starting from the form realm heavens, there are the four dhyānas and eight samāpattis. In the first dhyāna of the form realm’s first dhyāna heaven, the eye consciousness, ear consciousness, and body consciousness among the five consciousnesses are present and discern form dust, sound dust, and touch dust realms. Consciousness is also present, simultaneously discerning the dharma dust realms on these three dusts. However, if consciousness focuses on a single realm, mental attention is relatively unified and unscattered. At this time, consciousness can focus on contemplating a single Dharma principle, focusing on discerning the dharma dust of the meditative state. If consciousness attends to many realms, the mind scatters, and one may fall out of the first dhyāna concentration.

In concentrations from the second dhyāna upward, only solitary consciousness discerns the dharma dust of the meditative state alone; the first five consciousnesses do not exist. Therefore, solitary consciousness cannot know the dharma dust on the five dusts. In the concentration of non-perception (asaṃjñā-samāpatti), solitary consciousness also ceases; thus, there is no conscious mind to discern the dharma dust of the meditative state. None of the six consciousnesses exist; only the seventh consciousness (manas) and eighth consciousness (ālaya-vijñāna) exist, jointly maintaining the existence of the body so that the life-form does not vanish. In the Arhat’s cessation concentration (nirodha-samāpatti), there is also no solitary consciousness; no conscious mind discerns the dharma dust of the meditative state. Only the mental factors of attention (manaskāra), contact (sparśa), and volition (cetanā) of the seventh consciousness exist. Most crucially, the existence of the eighth consciousness ensures the body continues to exist without perishing.

So-called concentration is the mind abiding on a single realm, neither disturbed nor scattered. The minds in the first dhyāna and the “concentration not yet reached” can abide on one realm or primarily on one realm, paying no attention to other realms. When the conscious mind focuses on a single realm, because attention is concentrated and the seed-stream does not divert, its discerning power is strong, discernment becomes deep and subtle, differentiation is clear, and wisdom can arise. So-called wisdom is the clear and thorough discernment of things, enabling one to understand the true nature and meaning of phenomena.

(III) Dream Solitary Consciousness

Dream solitary consciousness is manifested solely by the Tathāgatagarbha. The first five consciousnesses do not manifest; only the conscious mind exists in the dream, discerning the dharma dust realms of the dream. The conscious mind alone differentiates the solitary-shadow realm of the dream. Without the first five consciousnesses, there are certainly no first five dusts; only the dharma dust discerned by the dream conscious mind exists.

In dreams, we seem to go to many places and do many things; we can freely travel to heaven and earth without any hindrance. In reality, we have done nothing and gone nowhere. Most people feel as if the first five consciousnesses exist in dreams, actively differentiating and functioning. In fact, the first five consciousnesses do not exist in dreams; only the conscious mind exists. This is called solitary consciousness. If the five consciousnesses existed, the body would move as when awake—that would not be sleep but wakefulness. Because in dreams, we suddenly shift from one place to another far away, even reaching heaven in the blink of an eye. If the first five consciousnesses existed, the body would necessarily move and follow to heaven or distant places. In reality, our body goes nowhere; it remains motionless in bed. Thus, the five consciousnesses do not exist in dreams.

If eye consciousness existed in dreams, our eyes would move with the transformation of form dust, but in reality, our eyes do not move in dreams. If deities appear in dreams, eye consciousness cannot see deities or ghosts. If deceased relatives appear in dreams, eye consciousness cannot see them. In dreams, if the five consciousnesses existed, when eating in a dream, the mouth and tongue should move, the stomach should contain food, and one should feel full—yet upon waking, one remains hungry. If the five consciousnesses existed in dreams, we could drink water or do anything, but in fact, our body does not move, and we still feel thirsty upon waking. Therefore, the five consciousnesses do not exist in dreams. Thus, in dreams, only the solitary conscious mind drifts with the realm; the first five consciousnesses do not exist. If the first five consciousnesses truly existed in dreams, they could control the body’s movement.

When the conscious mind exists alone in dreams, it is not restricted by time, location, the first five consciousnesses, or the body. It can instantly reach heaven, instantly go to other worlds, instantly return to past lives, and instantly traverse to future lives. With the first five consciousnesses present, none of this is possible because the body must move along, making it impossible to return to the past, traverse to the future, or ascend to heaven or descend to earth. Without the participation of the first five consciousnesses, there is no bodily involvement; only the conscious mind acts alone, unburdened by the physical body. Consciousness can then possess psychic powers (abhijñā), able to go anywhere regardless of past or future. With bodily involvement, we can go nowhere; we can only lie in bed asleep.

(IV) Deranged Solitary Consciousness

Deranged solitary consciousness is a pathological state and hallucination, a symptom of mental derangement. Consciousness cannot distinguish between reality and delusional, deranged realms; it produces hallucinations, mistaking illusions for reality, and becomes inverted and insane.

IV. The Nature of Consciousness in Dreams and Wakefulness

Whether dreaming or awake, what consciousness sees are images manifested by the Tathāgatagarbha. For the subtle sense faculties (indriyas), the mountains, rivers, and great earth of the waking state are equivalent to solitary-shadow realms. When a person awakens from a dream, they enter another dream, transitioning from solitary consciousness to five-concomitant consciousness—both are consciousness. In the waking state, scattered solitary consciousness functions simultaneously with five-concomitant consciousness and the five consciousnesses. Thus, the internal five dusts, internal dharma dust, and solitary-shadow realms appear and coexist simultaneously. When the mind is scattered, a person is in two dreams: one is a relatively realistic “direct-perception dream” (pratyakṣa dream), and the other is a purely imaginary “non-valid dream” (non-pramāṇa dream). Thus, consciousness is not unified, thinking is disordered, and wisdom struggles to arise. If consciousness has a focal point—either discerning only one dharma dust on the five dusts or only the non-valid solitary-shadow realm—it can still achieve concentration and give rise to wisdom. This is the unified state of chanting the Buddha’s name, contemplation, investigative meditation (vipaśyanā), and Chan (Zen) meditation.

V. The Formation and Nature of Dusts

Material form (rūpa) is composed of the four great elements (mahābhūtas): earth, water, fire, and wind. The five dusts of form, sound, smell, taste, and touch are also material form and thus composed of the four great elements. The dharma dust manifested on the five dusts is called “form included in the dharma base” (dharmāyatana-rūpa) and is also composed of the four great elements. When conditions cease, the four great elements decompose, the five dusts vanish and perish, and the form included in the dharma base on the five dusts also vanishes and perishes. Therefore, the six dusts are impermanent, arising and ceasing; they are not real—all are born and manifested by the Tathāgatagarbha.

Dharma dust belongs to form included in the dharma base; it is subtle material form, composed of the four great elements. The five dusts are material form, formed by the coarse four great elements, corresponding to the five sense faculties. On the five dusts, dharma dust is simultaneously manifested, corresponding to the mental faculty. When the five dusts correspond to the five faculties, the dharma dust simultaneously manifested on the five dusts corresponds to the mental faculty. Thus, the six faculties contact the six dusts, the eighth consciousness gives rise to the six consciousnesses, the six consciousnesses contact the six dusts, and then the mental factors of feeling (vedanā), perception (saṃjñā), and volition (cetanā) of the six consciousnesses arise.

On form dust, dharma dust is manifested. The eye faculty contacts form dust; the mental faculty contacts dharma dust. The eighth consciousness gives rise to eye consciousness and consciousness simultaneously contacting form dust and the dharma dust on form dust. The two consciousnesses differentiate form simultaneously but from different perspectives and with different degrees of subtlety: eye consciousness differentiates coarse form dust, while consciousness differentiates subtle form dust. When apart from the five dust realms, dharma dust can exist alone. The conscious mind functions alone to differentiate this solitary-shadow realm of dharma dust. At this time, the conscious mind is called solitary consciousness.

For example, after hearing a sound, consciousness falls into deep thought, repeatedly contemplating the meaning within that sound. This is the dharma dust realm corresponding to consciousness—there are no five dusts; it is a solitary dharma dust image, relatively subtle. Whenever, after discerning the six dust realms, one falls into contemplative thought, it belongs to solitary consciousness discerning a solitary-shadow realm. Also, in meditative states without the first five dusts, the conscious mind contemplates, recollects, analyzes, investigates, and observes alone; the resultant meditative form (dhyāna-nimitta) is a dharma dust realm without the five dusts, discerned solely by consciousness. In dreams without the first five dusts, consciousness acts alone in the dream—all these are solitary consciousness.

VI. Consciousness During Sleep

Whether dreaming or not during sleep, the five consciousnesses do not appear or manifest because dream realms belong to solitary-shadow realms—dharma dust realms discerned solely by solitary consciousness. During sleep, the six faculties still function; the external six dusts continuously enter the point of contact between faculties and dusts; the internal six dusts also continuously transform. Because the body is in a state of deep sleep and does not give rise to the six consciousnesses, it naturally cannot discern the six dusts.

Some claim that body consciousness participates during dreaming. If body consciousness truly participated, then when dreaming of ascending to heaven, the body would follow to heaven—yet the body remains on the bed, unmoved. When dreaming of being chased and fleeing, if body consciousness existed, the body would run who knows where and certainly not remain in bed. When dreaming of eating, if body consciousness existed, food would already be in the stomach, and upon waking, the stomach should be full—no need for breakfast. When dreaming of becoming wealthy, if body consciousness existed, gold, silver, and jewels would already be in pockets or stored, and upon waking, one should find them. When dreaming of cooking, if body consciousness existed, upon waking in the morning, food should be ready—no need to cook. From the above reasoning, it is clear that the five consciousnesses do not exist in dreams; only solitary consciousness discerns the solitary-shadow realm of the dream. Once the functions of the five consciousnesses are clearly understood, one knows whether the five consciousnesses appear in dreams.