Eight Consciousnesses, What is and isn't Yogacara

Eight Consciousnesses
-----Quotation from Dan Lusthaus’ article on “What is and isn’t Yogacara”

The most famous innovation of the Yogācāra school was the doctrine of eight consciousnesses. Standard Buddhism described six consciousnesses, each produced by the contact between its specific sense organ and a corresponding sense object. When a functioning eye comes into contact with a color or shape, visual consciousness is produced. When a functioning ear comes into contact with a sound, auditory consciousness is produced. Consciousness does not create the sensory sphere, but on the contrary is an effect of the interaction of a sense organ and its proper object. If an eye does not function but an object is present, visual consciousness does not arise. The same is true if a functional eye fails to encounter a visual object. Consciousness arises dependent on sensation. There are altogether six sense organs (eye, ear, nose, mouth, body, and mind) which interact with their respective sensory object domains (visual, auditory, olfactory, gustatory, tactile, and mental spheres). Note that the mind is considered another sense since it functions like the other senses, involving the activity of a sense organ (manas), its domain (mano-dhātu), and the consciousness (mano-vijñāna) resulting from the contact of organ and object. Each domain is discrete, which means vision, audition, and each of the remaining spheres function apart from each other. Hence deaf can see, and blind can hear. Objects, too, are entirely specific to their domain, and the same is true of the consciousnesses. Visual consciousness is entirely distinct from auditory consciousness, and so on. Hence there are six distinct types of consciousness (visual, auditory, olfactory, gustatory, tactile, and mental consciousness). These eighteen components of experience - viz. six sense organs, six sense object domains, and six resulting consciousnesses - were called the eighteen dhātus. According to standard Buddhist doctrine these eighteen exhaust the full extent of everything in the universe, or more accurately, the sensorium.

Early Buddhist Abhidhamma, focusing on the mental and cognitive aspects of karma, expanded the three components of the mental level - mind (manas), mental-objects (mano-dhātu), and mental-consciousness (mano-vijñāna) - into a complex system of categories. The apperceptive vector in any cognitive moment was called citta. The objects, textures, emotional, moral, and psychological tones of citta's cognitions were called caittas. Caittas (lit.: "associated with citta") were subdivided into numerous categories that varied in different Buddhist schools. Some caittas are "universal," meaning they are components of every cognition (e.g., sensory contact, hedonic tone, attention, etc.); some are "specialized," meaning they only occur in some, not all, cognitions (e.g., resolve, mindfulness, meditative clarity, etc.). Some caittas are wholesome (e.g., faith; lack of greed, hatred, or misconception; tranquility; etc.), some unwholesome, some are mental disturbances (kleśa) (appropriational intent, aversion, arrogance, etc.) or secondary mental disturbances (anger, envy, guile, shamelessness, etc.), and some are karmically indeterminate (torpor, remorse, etc.).

As Abhidharma grew more complex, disputes intensified between different Buddhist schools along a range of issues. For Yogācāra the most important problems revolved around questions of causality and consciousness. In order to avoid the idea of a permanent self, Buddhists said citta is momentary. Since a new citta apperceives a new cognitive field each moment, the apparent continuity of mental states was explained causally by claiming each citta, in the moment it ceased, also acted as cause for the arising of its successor. This was fine for continuous perceptions and thought processes, but difficulties arose since Buddhists identified a number of situations in which no citta at all was present or operative, such as deep sleep, unconsciousness, and certain meditative conditions explicitly defined as devoid of citta (āsaṃjñī-samāpatti, nirodha-samāpatti). If a preceding citta had to be temporally contiguous with its successor, how could one explain the sudden restarting of citta after a period of time had lapsed since the prior citta ceased? Where had citta or its causes been residing in the interim? Analogous questions were: from where does consciousness reemerge after deep sleep? How does consciousness begin in a new life? The various Buddhist attempts to answer these questions led to more difficulties and disputes.

Yogācārins responded by rearranging the tripartite structure of the mental level of the eighteen dhātus into three novel types of consciousnesses. Mano-vijñāna (empirical consciousness) became the sixth consciousness (and operated as the sixth sense organ, which previously had been the role of manas), surveying the cognitive content of the five senses as well as mental objects (thoughts, ideas). Manas became the seventh consciousness, redefined as primarily obsessed with various aspects and notions of "self," and thus called "defiled manas" (kliṣṭa-manas). The eighth consciousness, ālaya-vijñāna, "warehouse consciousness," was totally novel. The Warehouse Consciousness was defined in several ways. It is the receptacle of all seeds, storing experiences as they "enter" until they are sent back out as new experiences, like a warehouse handles goods. It was also called vipāka consciousness: vipāka means the "maturing" of karmic seeds. Seeds gradually matured in the repository consciousness until karmically ripe, at which point they reassert themselves as karmic consequences. Ālaya-vijñāna was also called the "basic consciousness" (mūla-vijñāna) since it retains and deploys the karmic seeds that both influence and are influenced by the other seven consciousnesses. When, for instance, the sixth consciousness is dormant (while one sleeps, or is unconscious, etc.), its seeds reside in the eighth consciousness, and they "restart" when the conditions for their arising are present. The eighth consciousness is largely a mechanism for storing and deploying seeds of which it remains largely unaware. Cittas occur as a stream in ālaya-vijñāna, but they mostly cognize the activities of the other consciousnesses, not their own seeds. For Yogācāra 'ignorance' (avidya) in part means remaining ignorant of what is transpiring within one's own ālaya-vijñāna. In states devoid of citta, the flow of cittas are repressed, held back, but their seeds continue to regenerate without being noticed, until they reassert a new stream of cittas. Warehouse Consciousness acts as the pivotal karmic mechanism, but is itself karmically neutral. Each individual has its own Warehouse Consciousness which perdures from moment to moment and life to life, though, being nothing more than a collection of ever-changing "seeds," it is continually changing and therefore not a permanent self. There is no Universal collective mind in Yogācāra.

Enlightenment consists in bringing the eight consciousnesses to an end, replacing them with enlightened cognitive abilities (jñāna). Overturning the Basis turns the five sense consciousnesses into immediate cognitions that accomplish what needs to be done (kṛtyānuṣṭhāna-jñāna). The sixth consciousness becomes immediate cognitive mastery (pratyavekṣaṇa-jñāna), in which the general and particular characteristics of things are discerned just as they are. This discernment is considered nonconceptual (nirvikalpa-jñāna). Manas becomes the immediate cognition of equality (samatā-jñāna), equalizing self and other. When the Warehouse Consciousness finally ceases it is replaced by the Great Mirror Cognition (Mahādarśa-jñāna) that sees and reflects things just as they are, impartially, without exclusion, prejudice, anticipation, attachment, or distortion. The grasper-grasped relation has ceased. It should be noted that these "purified" cognitions all engage the world in immediate and effective ways by removing the self-bias, prejudice, and obstructions that had prevented one previously from perceiving beyond one's own narcissistic consciousness. When consciousness ends, true knowledge begins. Since enlightened cognition is nonconceptual its objects cannot be described. Thus Yogacarins provide no descriptions, much less ontological accounts, of what becomes evident in these types of enlightened cognitions, except to say they are 'pure' (of imaginative constructions). One more Yogācāra innovation was the notion that a special type of cognition emerged and developed after enlightenment. This post-enlightenment cognition was called pṛṣṭhalabdha-jñāna, and it concerned how one who has understood things as they actually become (yathā-bhūtam) now engages the world to assist other sentient beings in overcoming suffering and ignorance.
------see http://www.acmuller.net/yogacara/articles/intro-uni.htm