t.k. from a talk at lunch today - Ok, to answer your question we must refer to the dynamics of reality as they manifest in Dzogchen.
Ngobo --> Rangzhin --> Thugsje
Tongpa – Salwa -- Rigpa
Brightness across expanse. An irreducible openness (ngobo) whose very essence is primordial purity (kadag) and whose spontaneity (lhundrup) IS brightness. And the two, in truth not two or one, but an immediacy and intimacy beyond numbers or concept - so close they are each others without which they can not exist.
Expanse is only expanse because of brightness. The brightness is a radiance and radiance is motion and motion requires extensity and so expanse comes into being because brightness’ activity demands it. A father becomes a father only when the son is born.
Spontaneous bright across expanse presences and reveals its own face. Rangzhin, is this movement - Reality’s unutterable essence ……..that is empty open nothingness, but not a mere nothingness – rather it is a plenum of pure potentiality. …. It is its own inherent urge to reveal its fullness that is not other than its openness. This revelation is bursting forth …. It is the spontaneous (lhundrup) movement of brightness (salwa) across-within, of-as the presencing of itself to itself as itself.
Presencing is resonance. What characterizes resonance is that it has quality - the resonance of a violin versus cello, and here is where extant qualities emerge from pure potential into the virtual. Resonance (thugsje) – the way in which the self presencing, self revealing, self disclosure of openness nothingness begins …. And its quality? Is tender-hearted compassion.
Brightness reveals itself as tender-heartedness (thug) which lords over (je). What does it mean it lords over? It means that it is the presiding substratum which then pervades whatever manifests from its energy - nothing is outside its domain. Whatever is made of gold is gold – a bowl, an earring, a ball made of gold are all gold. Appearing emerges from and within and as display of the resonance domain that is thugsje.
Mind’s ownmost urge is to reveal the plenum inherent within the quality-less, attribute-less, location-less openness that is as yet a nothingness (no thing-ness). Reveal to whom? To itself! And so ngobo--. Rangzhin--. Thugsje the essence the nature and the energy of awareness are this. ....... And thugsje is a resonance and a resonance across expanse is a resonance domain. And everything of this domain is not other than reality itself and is not elsewhere than reality itself. So this resonance pervades (Kunkhyab) …. The way sweetness pervades sugar, wetness pervades water, warmth pervades flame.
Even while dynamic openness nothingness, the unmanifest reality manifests as somethingness appearing...... it mysteriously remains an irreducible openness. It is like Meister Eckhart said in the 13th century in theistic terms “God flows out from the Godhead as everything without ever leaving the Godhead.” And as it says, I think in the SangNying, “This marvelous and wondrous truth is the mystery of all perfect Buddhas: From that which has no origin, everything that is has taken its origin, yet in having taken its origin, it remains that which has no origin.“
Irreducible openness nothingness mystery (ngobo) in its plethora of dynamics (rangzhin, thugsje ect) appears and yet remains irreducible openness. Appearance is not a step-down emanationism, or a reduced space (tzimtzum), it is the expressiveness of Buddha Nature in the fullness of its mystery and divinity. It is Reality's potency (tsal). Because it never leaves the non-dimensionality of openness it retains the dynamic activity which does not admit to any ultimate reduction. This activity is the true nature of emptiness as a verb (tongpa).
When I say mind’s true nature reveals itself to itself, I am saying that inherent knowingness (rigpa) which is an intensity of brightness, and also pervades expanse, knows itself in its ownmost display. Where rigpa recognizes the truth of appearing as the playful dynamics (rolpa tsal) of openness, this is called Buddha. When there is non-recognition, this is called sentient being.