ted a écrit :
Comment est-elle définie précisément dans les enseignements ?
Pour les écoles du bouddhisme tibétain, le texte de référence est l'Uttartantra Shastra de Maitreya.
Dans le chapitre sur "les quatre derniers points vajra", il est dit :
The Last Four Vajra Points
The virtuous Three Jewels, which are rare and sublime,
arise from suchness bound up with pollution, from the one free from pollution,
from the qualities of unpolluted buddhahood, and from the deeds of the Victor.
This is the object of those who see the ultimate truth.
The disposition of the Three Rare and Sublime Ones
is the object [of vision] of those who see everything.
Furthermore, these four aspects in the given order
are inconceivable, for the following four reasons:
[The buddha element] is pure and yet has affliction.
[Enlightenment] was not afflicted and yet is purified.
Qualities are totally indivisible [and yet unapparent].
[Activity] is spontaneous and yet without any thought.
Constituting what must be realized, realization,
its attributes, and the means to bring it about,
accordingly the first is the cause to be purified
and the [latter] three points are the conditions.
The Fourth Vajra Point: The Element
The perfect buddhakaya is all-embracing,
suchness cannot be differentiated,
and all beings have the disposition.
Thus they always have buddha nature.
The Buddha has said that all beings have buddha nature
“since buddha wisdom is always present within the assembly of beings,
since this undefiled nature is free from duality,
and since the disposition to buddhahood has been named after its fruit.”
Essence, cause, fruit, function, endowment, manifestation,
phases, all-pervasiveness of suchness, unchangingness,
and inseparability of the qualities should be understood
as intended to describe the meaning of the absolute expanse.
Just as a jewel, the sky, and water are pure
it is by nature always free from the poisons.
From devotion to the Dharma, from highest wisdom,
and from samadhi and compassion [its realization arises].
[Wielding] power, not changing into something else,
and being a nature that has a moistening [quality]:
these [three] have properties corresponding
to those of a precious gem, the sky, and water.
Enmity towards the Dharma, a view [asserting
an existing] self, fear of samsara’s suffering,
and neglect of the welfare of fellow beings
are the four veils of those with great desire,
of tirthikas, shravakas, and pratyekabuddhas.
The cause that purifies [all these veils]
consists of the four qualities [of the path],
which are outstanding devotion and so on.
Those whose seed is devotion towards the supreme vehicle,
whose mother is analytical wisdom generating the buddha qualities,
whose abode is the blissful womb of meditative stability,
and whose nurse is compassion, are heirs born to succeed the Muni.
The fruit is the perfection of the qualities
of purity, self, happiness, and permanence.
Weariness of suffering, longing to attain peace,
and devotion towards this aim are the function.
In brief, the fruit of these [purifying causes]
fully divides into the remedies [for the antidotes],
which [in their turn] counteract the four aspects
of wrong beliefs with regard to the dharmakaya.
The [dharmakaya] is purity, since its nature is pure
and [even] the remaining imprints are fully removed.
It is true self, since all conceptual elaboration
in terms of self and non-self is totally stilled.
It is true happiness, since [even] the aggregates
of mental nature and their causes are reversed.
It is permanence, since the cycle of existence
and the state beyond pain are realized as one.
Their analytical wisdom has cut all self-cherishing without exception.
Yet, cherishing beings, those possessed of compassion do not adhere to peace.
Relying on understanding and compassionate love, the means to enlightenment,
noble ones will neither [abide] in samsara nor in a [limited] nirvana.
If the buddha element were not present,
there would be no remorse over suffering.
There would be no longing for nirvana,
nor striving and devotion towards this aim.
... etc.
Sabba danam dhammadanam jinati - Le don du Dhamma surpasse tout autre don 
Pour clarifier ce que le Bouddhisme entend par "conscience" (skt. vijñana, tib. rnam shes) , "esprit" (buddhi, blo ou chitta, sems) "cognition" (jñana, shes pa/rig pa) *, qui sont synonymes pour l'épistémologie/psychologie bouddhiste: toute conscience a pour caractéristique conventionnelle (ou définition): ce qui est clair et cognitif ; et l'esprit a pour nature la claire lumière (skt. prabhasvaram idam chittam), ce qui revient exactement au même. Donc, pour résumer, selon l'ensemble du corpus de l'Inde (cf. Dhamakirti et son Pramanavarttika ou Nagarjuna et son Dharmadhatustavam entre autres exemples frappants) et du Tibet (cf. les commentaires aux Sutras du 3ème cycle, au Madhyamaka des Tantras supérieurs, au Dzogchen et au Mahamudra tantrique), la nature de bouddha est ce qui deviendra l'esprit éveillé du Bouddha (le Dharmakaya, conceptuellement distingué en Svabhavikakaya et Jñanadharmakaya), tandis que la méthode (les 5 premières perfections transcendantes dans les Sutras et le yoga de la déité dans les Tantras) deviendra le corps de forme du Bouddha (Rupakaya), c'est pourquoi la nature de bouddha (sauf pour le Madhyamaka tel qu'il est exposé dans les Soutras pour qui la nature de bouddha est la vacuité de l'esprit) est une conscience, un type d'esprit.
