The unity and differentiation of consciousness
Deep down the consciousness of mankind is one. This is a virtual certainty because even in the vacuum matter is one; and if we don't see this, it's because we are blinding ourselves to it.
David Bohm, Statement of 1986, as quoted in Towards a Theory of Transpersonal Decision-Making in Human-Systems (2007) by Joseph Riggio, p. 66
Consciousness cannot be accounted for in physical terms. For consciousness is absolutely fundamental. It cannot be accounted for in terms of anything else.
Erwin Schrödinger, As quoted in The Observer (11 January 1931); also in Psychic Research (1931), Vol. 25, p. 91
Consciousness is never experienced in the plural, only in the singular. Not only has none of us ever experienced more than one consciousness, but there is also no trace of circumstantial evidence of this ever happening anywhere in the world. If I say that there cannot be more than one consciousness in the same mind, this seems a blunt tautology — we are quite unable to imagine the contrary...
Erwin Schrödinger, "The Oneness of Mind", as translated in Quantum Questions: Mystical Writings of the World's Great Physicists (1984) edited by Ken Wilber
It is generally understood that all knowledge or experience (epistemology) of the world arrives through the sense organs. This is accurate, even obvious, as far as it goes. But, like all generalizations, it is only useful as a starting point for inquiring into particular knowledge; in this case particular knowledge concerning the true nature of knowledge. Some of the particular knowledge about knowledge that Zen regards as significant, is that the sense organs – eyes, ears, nose, tongue, body, and mind – are components of consciousness. Thus, while experience or knowledge of the world arrives through the sense organs, it is realized (made real) by and as consciousness. In this, then, we come to see; the known/experienced world is – exists as – consciousness itself.
The nondual perspective presupposes both a subject and an object are present in/as all instances of consciousness; in the absence of either, consciousness cannot exist. All knowledge/experience is the realization of a sentient being (subject; conscious existent) and a being of sentience (object; existent of consciousness). One thing this illumines is Zen’s recognition of the Buddha nature or wisdom of the human capacities for reasoning (dori) and discrimination – that is, Zen’s affirmation of the essential nature and role of the discriminating mind.
Contrary to the views commonly asserted in certain contemporary Zen circles, discrimination is an essential element of authentic Zen practice-enlightenment. Based on superficial notions of nonduality – notions confuse ‘nonduality’ with ‘oneness’ and/or ‘duality’ with ‘dualism’ – the negative or delusional nature of discrimination is commonly suggested, even explicitly asserted in popular accounts of Zen. Naturally, if one misunderstands ‘nonduality’ as meaning ‘oneness,’ one can only regard distinctions to be unreal or illusory. Similarly, to confuse ‘duality’ with ‘dualism’ can only lead to distorted views of plurality and variety. ‘Nondual’ means ‘not two,’ it does not mean ‘one.’ That ‘subjects’ and ‘objects’ are nondual means they are interdependent, not that they are inter-changeable, much less indistinguishable.
Zen distinguishes between subjects and objects because subjects are not objects, and objects are not subjects. In the context of knowledge, subject and object are coessential, coextensive foci; two distinct, mutually dependent elements of consciousness. The subject of an object has its place (dharma-position) in the universe which is not the same as the place as the object of the subject – consciousness, knowledge, or experience is a subject realizing an object and an object realized by a subject. In other words, the normality of subjects and objects is for subjects to be subjects and objects to be objects; objects exist as ‘what is realized’ by subjects, and subjects exist as ‘what realizes’ objects.