"By jointly discussing noumenon and phenomenon, one reaches the highest consciousness and creates right understanding among sentient beings." (Fatsang, 642712, founder of the Huayen Sect of Buddhism, based on the Avatamsaka Sutra).
'Positive' is not positive without 'negative', and 'negative' is not negative without 'positive'. Therefore they can only be two halves of one whole, two conceptual aspects of one whole that as a whole, cannot be conceived precisely because it is this which seeks to conceive.
'Being' cannot be without 'nonbeing', and 'nonbeing' cannot not be without 'being'. Therefore they can only be two conceptual aspects of one whole that as such cannot be conceived in which there is neither being nor non-being as objective existences.
'Appearance' (form) cannot appear without 'void' (voidness of appearance), and 'void' cannot be voidness of appearance without 'appearance'. Therefore they must be two conceptual aspects of what is objectively inconceivable as which their identity is absolute in non-objectivity.
'Subject' has no conceptual existence apart from 'object' nor 'object' apart from 'subject'. They, too, are twin spinning aspects of the inconceivable in which they are inevitably reunited.
Where there is neither positive nor negative, being nor non-being, appearance nor void, subject nor object, there must be identity. But identity cannot perceive itself, and that is what we are. That is why only he who does not know can speak, and why he who knows cannot speak for what-he-is cannot be an object of what-he-is, and so cannot be perceived or described.
Positive and negative, being and non-being, appearance and void, subject and object, can be conceived by us because as 'us' mind is divided into subject-conceiving and object-conceived but, re-identified with what they are, we are their total objective absence which is thought of as pure undivided mind.
"That alone is true Knowledge which is neither knowledge nor ignorance. What is known is not true Knowledge. Since the Self shines with nothing else to know or to make known, It, alone is Knowledge. It is not a void."*
* Ramana Maharshi's Forty Verses - V 12.
'Space' is a static three-dimensional concept, of which 'time' is the active counterpart, whose functioning constitutes a further direction of measurement. Space cannot be conceived without time (duration), nor time without space (extension). Two conceptual aspects of a unity that is inconceivable; given the name of 'spacetime', their identity is absolute in nonconceptuality. Unaccompanied by them, phenomena cannot be extended in appearance, and only as their noumenal source can be assumed to be.
'Phenomena' cannot be such without 'noumenon' nor 'noumenon' without 'phenomena'. Therefore conceptually they also are two aspects of non-conceptuality. Phenomena, being no things in themselves (devoid of self-nature) yet are everything, and noumenon, being the source of everything, yet is no thing. Everything, then, is both, and neither is any thing: eternally separate as concepts, they are forever inseparable unconceived, and that identity is the essential understanding.
That is what the universe is in so far as its nature can be suggested in words. The universe is inconceivable because what it is, is what we are, and what we are is what the universe is and that is total absence cognitionally which, uncognised, necessarily subsists as total presence.
"If it is said, that Liberation is of three kinds, with form or without form or with and without form, then let me tell you that the extinction of the three forms of Liberation is the only true Liberation." - Ramana Maharshi's Forty Verses - V. 40.
We cannot use mind to transcend mind: therefore noumenon (which is the abstract of mind) represents the limit of possible cognition.
'Noumenon' necessarily is total potentiality. If it functions, in functioning it must be subjective, and thereby inevitably objective also. That is to say, subject objectivises itself and so becomes apparent to itself as object, manifesting phenomenally 'within' itself. It looks at itself and perceives the universe which is then apparently outside itself, since objectivisation is a process of apparent exteriorisation.
Therefore the phenomenal universe is the objective aspect of noumenon.
This process comports the appearance of space and duration, without which objects could not have the necessary extension and without their extension there could be no cognition.
Phenomena, therefore, are not something projected by noumenon: they are the appearance of noumenon or noumenon rendered objective and apparent.
This functioning is what sentient beings are, and that extension in space-time is what we know as manifestation. In that appearance like all phenomena, of which our appearance is an aspect we have no nature of our own, but in this functioning (which is our nature) noumenality and phenomenality are identical.
This is why, thus manifested, we are not as such (phenomenally), and why we are as phenomenal noumenality (or noumenal phenomenality). Thus there is no duality in what we are, but only an apparent autonomous functioning which is the manifesting of nonmanifestation.
No entity is involved in what we are, for 'entity' is a phenomenal concept and every object, material or conceptual, that is phenomenal, is devoid of nature (is not). When the autonomous functioning, which is all that we are in manifestation, no longer functions, i.e., when it no longer extends itself in an apparent space-time continuum, this-which-we-are remains totally integrated in noumenality.
Noumenality as such cannot be recorded. What 'noumenality' represents neither is nor is not. It is necessarily incognisable, because totally devoid of objective quality, as mirrorness is, and because it is precisely what we are, and absolutely all that we are, whether nonmanifested or in apparent manifestation.
Yet the final word be with Huang-Po:
"There is no difference between sentient beings and Buddhas, or between Samsara and Nirvana or between delusion and bodhi. When all such forms are abandoned there is the Buddha."