Consciousness: The Key to Non-Duality

“Like clay in the modifications of clay, like gold in the modifications of gold, like thread in woven fabrics, so is the Infinite, the all-preceding, all-pervading Consciousness. It is without origin, without end, unchangeable and present in all phenomena. Ananda is the essence of all happiness flowing from Consciousness, the oceanic bliss in which all creatures are grounded.” (Anonymous, Sarvasāra Upanishad)

“To desire something other than this immediately present Consciousness is like having an elephant at home and still look for its footprints elsewhere... Thus it is that if you do not understand that everything comes from Consciousness, it will not be possible to achieve Buddha-hood... If you do not see that your own Consciousness is actually the Buddha, Nirvana will remain hidden.” (Padmasambhava, Self-Liberation Through Seeing With Naked Awareness)

“Through Her own Will, Consciousness unfolds the universe on the canvas that She Herself is... When this is fully seen, the mind – by turning inward – is expanded and revealed as pure Consciousness... By thus realizing your innate potential, you absorb the entire universe within yourself.” (Rajanaka Kshemaraja, The Recognition Sutras)

Non-Duality and Idealism
As the quotes above indicate, Consciousness plays a central role in the main forms of Eastern non-dual spirituality, namely Advaita Vedanta (first quote), Buddhism (second quote) and Shaivite Tantrism (third quote). Why? Why is Consciousness the key to non-duality? The short answer is: because, according to these traditions, our entire reality – i.e. everything we can experience and understand – exists only in Consciousness. All things, material objects no less than thoughts and feelings, can appear to us only in Consciousness. In this way, Consciousness is all-embracing, the Whole, the “Brahman”, the “One without second,” as the Upanishads say.

If you then realize that you are that Consciousness, that you are the One in which all things appear, you will see that you essentially coincide with the Whole, that you are the all-embracing, boundless space in which everything takes place. Everything is One; and that all-embracing One is Consciousness; and that Consciousness is you at your innermost core. This realization is the seed of Enlightenment, the realization of your true nature and the liberation from suffering. Your essence can no longer be touched by the things and events in the world, because from now on you know yourself as “That” which precedes the world, namely the Consciousness in which the world appears.

Immanuel Kant (1724-1804)

In philosophy, the idea that “everything is Consciousness” is known as Idealism – an idea that is also found in Western philosophy (in philosophers such as Berkeley and Kant and the contemporary thinker Bernardo Kastrup). The opposite view, Materialism, says that ultimately everything consists of matter, i.e. atoms, molecules, quarks, photons, etc. According to Materialism, Consciousness is nothing more than a by-product of material-mechanical processes, such as Darwinian evolution and electrochemical activity in the brain. Idealism, on the other hand, states that what we experience as material objects is ultimately nothing more than that: a bundle of experiences in our Consciousness, sensory sensations that are (mistakenly) interpreted by our mind as objects existing outside of us. So where Materialism says: “Matter produces Consciousness”, Idealism makes the inverse statement: “Consciousness produces matter”.

Materialism: A philosophy of despair and conflict
The debate between Idealism and Materialism may seem abstract and academic, far removed from everyday life, but on closer inspection the opposite is true. From the Scientific Revolution in the 16th and 17th centuries onward, Materialism has steadily grown into the dominant worldview of Western civilization. As such, Materialism has exerted an enormous – and very harmful – influence in our culture. It is not for nothing that the word “materialism” is synonymous with greed and the exclusive focus on material possessions. The most important cultural consequence of scientific Materialism has undoubtedly been modern individualism, an extreme form of the dualistic belief in the reality of the separate ego.

The seemingly separate ego experiences itself as detached from – and at odds with – an indifferent outside world, in which it must struggle to maintain itself. Materialism naturally leads to belief in separation because this philosophy sees Consciousness as a by-product of the brain. In that case, Consciousness is by definition tied to an individual and mortal body, and thus different from individual to individual. In this way, Materialism is in large part responsible for the suffering that the dualistic belief in separation entails: egoism, greed, exploitation, feelings of inferiority, hatred, abuse, violence… These are all thoughts, feelings and behavioral patterns that originate in the conviction that I – as this person, with this body and this mind – am nothing more than this individual being, separate from the other people around me, separate from nature, separate from the Universe, separate from the Divine...

Thus the Advaita teacher Rupert Spira (2017: 2) calls Materialism “a philosophy of despair and conflict, and, as such, the root cause of the unhappiness felt by individuals and the hostilities between communities and nations”. That is why the debate between Idealism and Materialism is not just theoretical and academic: ultimately, the fate of Western civilization is at stake here. The choice between Idealism and Materialism is the fundamental choice we have to make between universal unity and harmony on the one hand and the destructive effects of competitive individualism on the other. This is a particularly weighty choice in the light of the impending climate apocalypse and the continuing hardening of both society and international politics.

Non-duality not an intellectual game
Now, we could put forward a whole arsenal of theoretical arguments in favor of Idealism and against Materialism – for example, the fact that Materialism fails to explain Consciousness (which is known in philosophy as “the Hard Problem of Consciousness”), or the constitutive role of the observer in quantum mechanics, or the old epistemological argument that we cannot know anything outside of Consciousness (an argument found both in Western philosophers such as Berkeley and Kant and in Eastern traditions such as Yogacara Buddhism and Shaivite Tantrism). From a theoretical perspective, such arguments are of course very important and – in my opinion – ultimately convincing.

But when it comes to Enlightenment through non-dual Consciousness, these arguments are less relevant. Non-duality is much more than just theory, and certainly not a purely intellectual game with philosophical subtleties. Non-dual spirituality is primarily about the living realization of Enlightenment by directly experiencing the existential truth behind Idealism, i.e. by discovering oneself as the one Consciousness underlying everything and everyone.

This also indicates the main difference between Western Idealism and the non-dual spirituality of the East. Although both see Consciousness as the ultimate reality, Western Idealism remains stuck in purely theoretical arguments and does not penetrate into the experiential dimension of Enlightenment, the direct intuition of non-dual Consciousness. Whereas it is precisely this redeeming experience that is the central motive of Eastern spirituality. In Advaita, Tantra and Buddhism, philosophical theory and rational argumentation are certainly not lacking, but they are secondary to the practical pursuit of Enlightenment. In his classic book Philosophies of India, Heinrich Zimmer aptly describes this difference between Western and Indian philosophy as follows:

“India [...] has had, and still has, its own disciplines of psychology, ethics, physics, and metaphysical theory. But the primary concern – in striking contrast to the interests of the modern philosophers of the West – has always been, not information, but transformation: a radical changing of man’s nature and, therewith, a renovation of his understanding both of the outer world and of his own existence; a transformation as complete as possible […]. The attitudes toward each other of the Hindu teacher and the pupil bowing at his feet are determined by the exigencies of this supreme task of transformation. Their problem is to effect a kind of alchemical transmutation of the soul. Through the means, not of a merely intellectual understanding, but of a change of heart (a transformation that shall touch the core of his existence), the pupil is to pass out of bondage, beyond the limits of human imperfection and ignorance, and transcend the earthly plane of being.” (Zimmer 1953: 4-5)

The Eastern contribution: Consciousness is not individual
In the following, therefore, I will not go into the many arguments that can be given for Idealism and against Materialism. Instead, I will focus on one specific argument from Eastern philosophy about the fundamental nature of Consciousness – an argument that directly touches on the experience of Enlightenment. It also addresses one of the main objections raised by Westerners when confronted with non-duality. As said, non-duality is about discovering yourself as the one, all-embracing Consciousness underlying everything and everyone. For most Westerners, that’s a rather absurd idea, trapped as they are in the – ultimately Materialistic – belief that Consciousness is always individual, because always tied to an individual body.

For Westerners, the Materialist assumption that Consciousness is in one’s head, and in particular in the brain, is very natural; it’s what they are brought up with. As said, if Consciousness is in the brain, then Consciousness is by definition of an individual nature, tied to an individual body. It is striking to see that even Western thinkers such as Berkeley and Kant have – despite their Idealism – not been able to escape this Materialist assumption of the individuality of Consciousness. In this respect, Eastern philosophy shows a very different and, above all, more consistent picture. For if we start from the plausible idea that the Consciousness necessarily precedes the phenomena appearing in it, then the strictly impersonal, pre-individual nature of Consciousness follows automatically.

After all, everything that characterizes you as you – your body, your thoughts, your feelings, your character, your social position, your country, your culture – all these things are objects perceived by Consciousness and are therefore preceded by Consciousness. Consciousness is not in your head or brain, on the contrary: your head and brain are, as objects of experience, in Consciousness. Everything that individualizes us, everything that makes us into different individuals – bodies, thoughts, feelings, personal histories, etc. – all these things appear in Consciousness, which as such precedes all of them and is therefore not defined by any of them. The entire talk of “individual consciousness” is nonsensical.

It is only through Consciousness that can we see, feel, perceive, think, understand objects. Consciousness itself, therefore, is not one of those objects – that is to say: it is not a thing itself, and in that sense it is a kind of nothing, a “no-thing”. As Nisargadatta puts it: “Resolutely reject what you are not, till the real Self emerges in its glorious nothingness, its not-a-thing-ness.” (2009: 503) By thus realizing the true nature of one’s Consciousness, one ceases to experience oneself as a particular individual, limited in space and time. Rather, one transcends space and time, which are now seen as mere appearances in Consciousness. Thus Nisargadatta again: “In reality time and space exist in you; you do not exist in them.” (2009: 196)

A widely used metaphor in Eastern philosophy is that Consciousness is the Light in which everything can appear. Of course, this is not about light in the physical sense of the word (a stream of photons), but about the ‘spiritual’ Light in which all objects (including photons) become manifest, i.e. perceptible, knowable and understandable. Therefore, Consciousness itself cannot be perceived or understood as an object: the pure Light in which all things appear cannot itself appear as a thing. In that sense, Consciousness itself is completely featureless, indefinite and formless.

Consciousness: a limitless void
Properties are always determined and as such different from other properties. Red is red because it is different from other colors, long is long because it is different from short, warm is warm because it is different from cold, and so on. In philosophy, this is often expressed in terms of Spinoza’s statement that “omnis determinatio est negatio”, that is, every determination (of a property) is a denial (of another property). In that sense, each property is necessarily finite because essentially limited by other properties. But properties can only appear to us in Consciousness, which is why Consciousness itself is without properties: it precedes all of them. Consciousness is therefore not finite as properties are: it is infinite, limitless...

This already shows that all individuals share the same universal Consciousness. We have seen that Consciousness – as a condition for the appearance of objects – must itself be completely indeterminate and limitless, a kind of infinite ‘no-thing’ that precedes all ‘some-things’. But how many of such ‘no-things’ – how many indeterminate and limitless Consciousnesses – can there be? It is obvious that only one can exist. Because suppose there are several. How then do you compare them to each other? How do you compare multiple ‘no-things’? Clearly, this is impossible: these ‘no-things’ do not have any properties that can be used for comparison. Hence: there is only one Consciousness.
 

Put differently: if we were to say that ‘my’ consciousness differs from ‘your’ consciousness, then they must somehow have (different) properties. Our consciousnesses must then be limited in some way, for then there must be some kind of boundary between ‘my’ consciousness and ‘your’ consciousness. But how is that possible if Consciousness is indeterminate and limitless? Of course, you are aware of different things than I am. For example, you eat an apple while I drink a cup of tea; you feel cheerful while I am sad; you think of your grandmother, while I think of the pain in my back, etc. But these differences all concern the objects in Consciousness. That which perceives these objects, i.e. Consciousness itself, is exactly the same for both of us: featureless, boundless, formless... Seen in this way, I cannot distinguish ‘my’ Consciousness from ‘your’ Consciousness. The whole difference between ‘mine’ and ‘thine’ dissolves in the limitless void of pure Consciousness.

The “neti, neti” formula
Let us return to the fact that properties can only be determined in relation to each other, by differing from each other. This accounts for the famous phrase “neti, neti” (“not this, not this”) which traditionally denotes Consciousness in the Vedanta – an expression that is already found in the oldest Upanishad: “With what means can one perceive that through which one perceives this whole world? About this Self one can only say “neti, neti”.” (Brihadaranyaka, 4.5.15)

This double negation indicates that Consciousness is not characterized by any property, therefore not by any property A or by the opposite property non-A (from which A must differ in order to be A). For example, if I merely said “Consciousness is not large”, I would leave open – due to the relational nature of properties – the possibility that Consciousness is small. It is to exclude this possibility that the phrase “neti, neti” is used. Through this phrase it becomes clear that Consciousness is completely beyond the relational dimension of mutually limiting properties – as the Brihadaranyaka Upanishad (3.8.8) says: “it is neither gross nor subtle, neither short nor long”, and so on.

Thus, the non-duality of Consciousness does not just mean that there is no longer any subject-object duality (although that’s the main meaning of it); it also means that Consciousness is essentially beyond (or before) the dualities of our empirical, property-determined world. Consciousness is neither cold nor warm, neither large nor small, mind nor matter, male or female, good nor evil, etc.

The “groundless openness” of the space of Consciousness
Clearly, we are reaching the limits of language and conceptual thinking. How can one talk and think about something that has no properties, something indescribable, something ineffable? To meet this exigency, Advaita, Tantra and Buddhism employ various metaphors to indicate the non-objectifiable essence of Consciousness. We have already got to know one of these metaphors, namely the Light in which all objects become visible, but which itself cannot be seen as an object.

A closely related metaphor is that of the empty sky or space in which material objects can find a place. That space necessarily precedes all objects and is therefore not an object itself. In that sense one can say that Consciousness “gives space” to all phenomena – or rather: it is that space, that indefinite and infinite openness in which everything can appear. Enlightenment is about experiencing oneself as this infinite space in which everything happens.
 

Thus Nisargadatta often used to ask his visitors questions like: “Have you ever felt the all-embracing emptiness in which the universe swims like a cloud in the blue sky?” (2009: 330) The Dutch Advaita philosopher Douwe Tiemersma, who also happened to be one of Nisargadatta’s students, aptly spoke of the “groundless openness”, i.e. the boundless and open space of Consciousness that is “groundless” because there is nothing outside of it and that therefore does not depend on anything (it is its own ground, one could say).

Of course, this is not about space in the scientific sense of the word, i.e. not the geometric space of mathematics or the physical space of physics. These spaces are objects in Consciousness, since they can be studied scientifically. As such, they presuppose an even more fundamental space, the space of Consciousness in which they can appear as objects. In that sense, Consciousness is “the space behind space” or “the space around space”, i.e. the indefinite and groundless openness in which the geometric and physical spaces can first come to appearance. This is what the Chandogya Upanishad means with the following remarkable passage:

“As immeasurable as the space around is this space in the Heart, which contains both the earth and the sky, both fire and wind, both the sun and the moon, both lightning and stars… Now, what is called space is that which generates name-and-form (nama-rupa). That in which they are grounded – that is Brahman; that is the Immortal, that is the Self.” (Chandogya Upanishad, 8.1.3 & 8.14)

Consciousness and Enlightenment
The last sentence of the above quote – “that is Brahman; that is the Immortal; that is the Self” – points to the importance of the non-dualistic view of Consciousness for the ideal of Enlightenment in Advaita, Buddhism and Tantra. To begin with, we have to see that this indeterminate and limitless space of Consciousness is our deepest Self, or rather our deepest I. For the third-person form of “the Self” can create the dualistic impression that it is about something apart from us, standing over against us, a divine He, while the point is precisely the non-dualistic insight that we are “That” ourselves. After all, I am aware of all my experiences, feelings and thoughts. I am the observer to whom the world appears. I am the subject to which all objects appear but who can never become an object itself. In short, I am that featureless, boundless Consciousness that underlies and precedes all phenomena.

The seeing of this is what Enlightenment is, Awakening, the liberation of suffering. All experiences, thoughts, feelings appear in Consciousness, but they do not touch Consciousness; it remains featureless, formless, unmoved – just as a theater remains unmoved by the drama that takes place in it, or as a cinema screen is not touched by the film it displays. As the Brihadaranyaka Upanishad says, Consciousness is “the one who is beyond hunger and thirst, beyond sadness and confusion, beyond old age and death” (3.4.2).

Although Advaita, Buddhism and Shaivite Tantrism place slightly different accents and use different terminologies, the essence is always the same insight, namely that you are primarily this non-dual Consciousness and not one of the limited phenomena that show up in Consciousness. In a following post I will elaborate on the relationship between Advaita, Buddhism and Tantra. The superficial differences that indeed exist between these traditions should not obstruct our view of the liberating core message they have in common.

References
-Heinrich Zimmer, Philosophies of India, edited by Joseph Campbell, 1953, Routledge and Kegan Paul.
-Nisargadatta, I Am That, edited by Sudhaker S. Dikshit, translated by Maurice Frydman, Chetana, 2009.
-Philip Renard, Non-Dualisme: De Directe Bevrijdingsweg, 2005, Felix Uitgeverij (p. 103 for the Padmasambhava quote).
-Rajanaka Kshemaraja, The Recognition Sūtras, translated and annotated by Christopher Wallis, 2017, Mattamayūra Press.
-Rupert Spira (2017), The Nature of Consciousness: Essays on the Unity of Mind and Matter, Sahaja Publications.
-Wim van de Laar, De Upanishads, translated and annotated by Wim van de Laar, 2015, Uitgeverij Nachtwind.

"Atman is Brahman" – How Absolute Idealism originated in Indian Philosophy

Absolute Idealism is a much misunderstood philosophical tradition. At least two stubborn prejudices stand in the way of its proper reception. One is that Absolute Idealism was refuted at the beginning of the 20th century by the founding fathers of Analytic Philosophy, and that it has henceforth become obsolete. In my previous post I already adduced several arguments why this view is wrong, i.e. why Absolute Idealism is in fact still 'alive and kicking'. In this post I want to focus on the second prejudice, namely, that Absolute Idealism was first and foremost a creature of the 19th century, created by the post-Kantian German Idealists (Fichte, Schelling and Hegel) and then taken up and developed further by the Anglo-American Idealists (Green, Bradley, McTaggart, Royce).

In this post I want to show that Absolute Idealism did not originate in early 19th century Germany but rather in ancient India from roughly 1000 to 500 BCE. There the Hindu religious tradition, as originally expressed in the Vedas, underwent a radical transformation culminating in the Upanishads, the fons et origo of philosophical speculation in Indian thought (the Sanskrit term "Upanishad" literally means "sitting down near" and refers to the practice of a student sitting down near the teacher in order to receive esoteric teaching). During this transformation, the polytheism of the early Vedic religion was gradually rationalized into a philosophical monotheism which in the Upanishads took on the character of an Absolute Idealism, i.e. the belief in a transcendent Conscious Self – annunciated in the principle that "Atman is Brahman" – as the absolute ground of all reality. The resulting philosophical system, called Vedanta, will be the topic of this post. Please note that all quotes from the Upanishads are taken from the translation by Sarvepalli Radhakrishnan (1953).

Was Absolute Idealism invented in the 19th century?
Absolute Idealism is often viewed as a creature of the 19th century, created by the post-Kantian German Idealists. A typical example of this view can be found in The Routledge Dictionary of Philosophy: "Absolute idealism developed after Kant, notably with Hegel, and was popular in Britain from about 1865 to 1925. It takes many forms, but its central point is that there is only one ultimately real thing, the Absolute, which is spiritual in nature. Other things are partial aspects of this, or illusory appearances generated by it. Here idealism becomes a form of MONISM. The Absolute is so called because it alone does not depend on or presuppose anything and does not have its properties relative to something else." (Proudfoot & Lacey 2010: 173)

The substantive definition of Absolute Idealism given by the Routledge Dictionary is in itself – in all its brevity – quite adequate and instructive. But its historical claim that "Absolute idealism developed after Kant, notably with Hegel" is a flagrant case of historical myopia (or Eurocentrism, if you will). To be sure, the term "Absolute Idealism" originated with the post-Kantian German Idealists, who self-applied it in order to characterize their philosophy in contradistinction to Kant's Critical Idealism. But the philosophical point of view indicated by that term – the belief in a spiritual Absolute as the ultimate ground or essence of reality – is much older. In fact, it is as old as philosophy itself.

In the West the clearest case of Absolute-Idealist thinking prior to the German Idealists is the Neoplatonism of Plotinus, whose vision of the One clearly anticipated the doctrine of the Absolute as later developed by the post-Kantian Idealists (see Bréhier 1958; Beierwaltes 2004). But already well before Plotinus we find hints of Absolute-Idealist thinking in pre-Socratic Greek philosophy, notably in Parmenides of Elea. His notorious claims that "thinking and being are the same" and that "all things are one, and this one is Being" are sometimes interpreted along Absolute-Idealist lines (see e.g. Dunham, Grant & Watson 2011: 10-18). But the few surviving fragments of his writings are too scanty to warrant any definite conclusions about what his philosophy amounted to.

If we want to find the true origin of Absolute Idealism – or at least its oldest recorded manifestation – we have to leave the West behind and journey not only deeper into the past but also further to the East, namely, to India in the 8th to 5th centuries BCE. This was a crucial period in human history, the so called Axial Age (Karl Jaspers), when from Greece to China independent rational thought first broke free from the bondage of traditional religious dogmas and myths. In India this step was accomplished by the anonymous sages behind the Upanishads as they began to rationalize the polytheistic mythology of the Hindu religion, as expressed in the Vedas, into a philosophical monotheism.

The result was the world's first full-blown system – or rather family of systems – of Absolute Idealism, precisely as defined above by the Routledge Dictionary: an Idealistic Monism recognizing only one 'thing' as ultimately real, the Absolute, which is spiritual in nature, and of which all other things are partial aspects or illusory appearances. As Radhakrishnan notes, "the general spirit of Indian thought", of which the Upanishads are the original source, "has a disposition to interpret life and nature in the way of monistic idealism, though this tendency is so plastic, living and manifold that it takes many forms and expresses itself in even mutually hostile teachings." (Radhakrishnan 1989: 32) At the end of this post, I will return to the different forms taken by this Idealistic Monism which is pervasive in Indian thought. First, however, we will take a closer look at the central ideas of the Absolute Idealism expressed in the Upanishads.

Brahman, the Vedantic Absolute
Those unfamiliar with Indian philosophy may be forgiven for never having heard of Hindu Absolute Idealism, since the terminology commonly used in relation to it is so very different. The resulting philosophical system (or rather family of such systems) is not usually known as Absolute Idealism but rather as Vedanta, literally meaning "end / culmination of the Vedas". Likewise for the spiritual Absolute as the ground of all reality, which in the Vedanta is known as Brahman – a term of unclear etymological origin, supposedly deriving from a Sanskrit root meaning "to grow, to burst forth". In the older Vedas "Brahman" meant primarily mantra or ritual prayer. It was only later, at the time of the earliest Upanishads, that the term came to indicate the object of prayer, that which is invoked by the prayer, the growing force underlying and permeating the universe (cf. Keith 1989: 445; Radhakrishnan 1989: 163, n.1).

Exactly how and why this semantic transition from "Brahman" as mantra to "Brahman" as the Absolute occurred is an interesting question which I will investigate in a following post. Let us now simply note that through this transition "Brahman" came to stand for the Absolute qua unconditioned ground of all reality (cf. Radhakrishnan 1953: 66). Brahman is that which explains all reality and which as such cannot be explained by anything other than itself. It is "that which, being known, everything else becomes known" (Mundaka Upanishad: 672). It is "the self-caused" (Katha Upanishad: 630; Svetasvatara Upanishad: 747). It "created itself by itself" (Taittiriya Upanishad: 549). And as such it is not relative to anything else but is "one without a second" (Chandogya Upanishad: 447-8).

To appreciate the revolutionary novelty of such an all-inclusive explanatory approach to reality, we only have to take a look at classical Greek philosophy. There anything comparable to the Vedantic notion of Brahman emerged only many centuries later in the Neoplatonism of Plotinus, whose concept of the One points to a similarly self-creating Absolute. (There is even some evidence suggesting that Plotinus was influenced by the Vedanta; see Bréhier 1985.) Thus the Plotinian One represented a revolutionary development in Greek philosophy, where the existence of reality had always been taken for granted as unproblematic, as needing no explanation.

This can be seen from the fact that neither Plato's Demiurge nor Aristotle's Unmoved Mover presents us with an all-creating Deity. Leibniz’s famous question “Why is there something rather than nothing” simply did not occur to the ancient Greeks. They probably would have rejected that question as nonsensical. This has a lot to do with the fact that the Greeks simply had no conception of absolute nothingness (what philosophers nowadays call the "null state" in which nothing at all exists), which is reflected in the fact that they did not have the mathematical concept of zero either. For the Greeks it was simply unimaginable that the universe might not have existed.

The role of nothingness in late Vedic thought
The situation was very different in ancient India. There an acute philosophical awareness of the ontological possibility of absolute nothingness was already well in place before 1000 BCE, as testified by the famous Hymn of Creation (from the Rig Veda) which begins by describing the state preceding the creation of the universe: "Non-being then existed not nor being" (Radhakrishnan & Moore 1957: 23). As to why the ancient Indian mind, in contrast to the classical Greek mind, was so much more alive to the ontological possibility of nothingness we can only speculate. One reasonable speculation is that the explanation lies in the practice of meditation in ancient India (first termed "yoga" in the Upanishads), which had no counterpart in classical Greece. The "emptiness of consciousness" attained in meditation may very well have been the experiential source of the Indian concept of nothingness.

Fact is that this concept played an important role in Indian philosophy from early on. Note, for example, the philosophical acumen displayed by the anonymous author of the Hymn of Creation in his conscious effort to avoid ascribing existence to nothingness as a result of his negation of existence: at the beginning "being" did not yet exist but neither did "non-being". This shows a clear awareness of the logical paradoxes surrounding the concept of nothingness (comparable, for example, to Carnap's critique of Heidegger's concept of nothingness). As a result of this philosophical familiarity with the concept of nothingness, the urgency behind the question why something exists rather than nothing was sharply felt in ancient Indian thought. Thus, after having introduced the paradoxical notion of the void preceding the creation of the universe, the Hymn of Creation asks: "Whence was it born, and whence came this creation? / The gods were born after this world's creation. / Then who can know from whence it has arisen?" (Idem: 23-4) In this free questioning spirit, this skeptical and almost sacrilegious attitude towards the Vedic polytheism from which it sprang, the Hymn of Creation already makes the transition away from traditional myth towards independent rational thinking, pointing forwards to the Upanishads

The inward turn of the Upanishads
The ancient Indian mind, in its acknowledgement of the (paradoxical) possibility of nothingness and its subsequent search for the explanation of reality as such, was remarkably modern – more so than classical Greek thought. In a way the Upanishadic sages anticipated Leibniz's rationalist Principle of Sufficient Reason, according to which there is an explanation for every fact, including the fact of reality's existence. The ancient Indian sages were the first philosophers in the world to feel this need to explain everything, as witnessed by their revolutionary postulation of Brahman as the self-causing cause of all reality. Thus the nagging questions raised in the Hymn of Creation – what preceded the creation of the universe? why and how did that creation occur? – received answers in the Upanishadic period.

The answers, we must stress, followed from a decisive new turn in Indian thought: the turn inwards, towards the mystery of human self-awareness as the key to the mystery of the cosmos. As Radhakrishnan writes: "When we pass from the Vedic hymns to the Upanishads we find that the interest shifts from the objective to the subjective, from the brooding on the wonder of the outside world to the meditation on the significance of the self. The human self contains the clue to the interpretation of nature." (Radhakrishnan 1953: 49)

It was this revolutionary turn inwards, towards the human self (the Atman), that finally turned Brahman into the Hindu equivalent of the Idealistic notion of the Absolute. The spiritual nature of Brahman as identical with Atman is announced in what are known as the four "Great Sayings" (Mahaavaakyas) of the Upanishads: (1) "Conscious is Brahman" (Aitareya Upanishad); (2) "This Self (Atman) is Brahman" (Mandukya Upanishad); (3) "Thou art That" (Chandogya Upanishad); (4) "I am Brahman" (Brihadaranyaka Upanishad). Each of these sayings is a formulaic expression of the same idea: that the single and all-encompassing Brahman is in essence identical with the human Self – or, in other words, that the empirical plurality of individual human selves is really an illusion, because in reality there is only one Self, the Atman, the Universal Self which is Brahman. Thus the Upanishads declare that Brahman, as the absolute ground of reality, is in essence a conscious self.

Atman, the Universal Knower
Why did the Upanishadic sages make this inward turn? Why did they single out the human self as holding the key to the nature of the Absolute? As I will show in a following post, this is a very intriguing question that is not easily answered. Part of the story has to do with epistemology. For one of the things that impressed the Upanishadic sages in the self is its epistemological aspect, i.e. the relation of the self to sense experience and knowledge. We already noted how the Upanishads are remarkably modern in their anticipation of Leibniz's Principle of Sufficient Reason and the concomitant question why there is something rather than nothing – a question that did not arise for the ancient Greeks. This remarkable modernity of the Upanishads also comes to the fore in the sharp awareness the Upanishadic sages had of the epistemological centrality of the self, insofar as they stressed the thoroughgoing dependence of objective empirical reality on the conscious subject to whom this reality appears. In this way the Upanishads anticipated the epistemological Idealism of modern philosophers such as Berkeley, Kant and Husserl. Much like the Kantian transcendental subject, the Vedantic Brahman was conceptualized as the universal Knower, the universal subject underlying all experience, thinking and knowledge.

Here the contrast with classical Greek philosophy is again instructive. The historian of ancient Greek philosophy M.F. Burnyeat (1982) has famously argued that epistemological Idealism was entirely absent in ancient Greece. He pointed out that although there certainly was epistemological skepticism in Greek philosophy (though mostly in its post-Classical, Hellenistic period), this skepticism never went so far as to doubt – let alone deny – the existence of an external reality (i.e. a reality independent from our consciousness of it). According to Burnyeat, such thoroughgoing skepticism became possible only after Descartes' cogito ergo sum argument, which placed the evidential basis for all certainty firmly within our consciousness and its representations ("ideas", "Vorstellungen") – representations from which the evidence for an external reality then had to be reconstructed. Only after this Cartesian turn to consciousness had been taken did it become possible for philosophers to deny the existence of any reality beyond our consciousness and thus for modern Idealism to arise.

But Burnyeat's thesis is expressly limited to Western philosophy. The situation in ancient Indian philosophy was, again, very different from early on. As we have seen, there something very much like the Cartesian turn to the subject had already been accomplished in the Upanishads with its inward turn, when the human self was chosen as the preferred model for understanding the nature of Brahman. And as said, what impressed the Upanishadic sages in the human self was partly its epistemological aspect, i.e. the fact that the self is presupposed by every experience, thought and feeling. A sensory experience is always experienced by a self; a thought is always thought by a self; a feeling is always felt by a self... But since, according to the Upanishadic sages, there is in truth only one Self, the universal Atman which is Brahman, they concluded that this Self must be the universal subject underlying all cognition.

In this way the Upanishadic concept of Atman came surprisingly close to the Kantian conception of the transcendental subject which underlies and unifies all individual acts of knowledge. Thus Brahman became "the knower of all" (cf. Mandukya Upanishad: 697; Svetasvatara Upanishad: 747), the universal "seer of seeing", "hearer of hearing", "thinker of thinking", "understander of understanding" (Brihadaranyaka Upanishad: 220), the universal "witness" (Svetasvatara Upanishad: 746). The famous Vedantic scholar Shankara (ca. 788 – 820 CE) likewise calls Brahman "the witness of all experiences" (1975: 83). This means that reality is effectively reduced to an experience of Brahman, since the latter is also the cause of everything, the Absolute underlying all reality. That is to say: reality exists only insofar as it appears to Brahman, i.e. insofar as it is seen, heard, smelled, understood (and so on) by Brahman. With this step the Absolute Idealism of the Upanishads becomes complete: reality is nothing but a mental construct created by Brahman.

Pantheism vs. acosmism in the Vedanta
It is, however, in relation to this question – How does empirical reality relate to the single Brahman? – that considerable differences emerge in the Upanishads and also in later developments of the Vedanta. This is why, as noted earlier, the Upanishads do not present a single system of Absolute Idealism but rather a family of such systems. The Upanishads do not at all speak in one voice. Although all start out from the basic identity "Brahman is Atman", different strands in the Upanishads unpack this identity in different ways. Two basic strands or families can be distinguished: (1) the acosmic strand in which empirical reality is declared to be an illusion, since only the object-less consciousness which is Brahman exists, and (2) the pantheistic strand in which the reality of the empirical world is fully recognized and subsequently explained as an expression or manifestation of the consciousness which is Brahman.

This difference turns on how the consciousness which is Brahman is conceived: as self-consciousness or rather as object-less consciousness? Each view is associated with the name of a legendary Upanishadic sage. The first view, mainly associated with the sage Uddalaka, lays more stress on the self-hood of Brahman, viewing its consciousness as essentially self-consciousness. The other view, mainly associated with the sage Yajnavalkya, downplays the self-hood of Brahman and views its consciousness as essentially object-less and thus not as consciousness of a self at all, but rather as an empty consciousness, a pure consciousness without an object. Yajnavalkja appears prominently in the Brihadaranyaka Upanishad and Uddalaka in the Chandogya Upanishad – the two oldest Upanishads, dating roughly from the 7th to 6th centuries BCE.

These different views have different implications for the relation of Brahman to the empirical world, the universe. The view associated with Uddalaka, which stresses that Brahman is essentially self-conscious, tends to see that relation as one of expression and participation: the universe is a progressive manifestation of Brahman, who gradually expresses himself (or rather itself) in the universe, reaching its fullest manifestation only in those sages who – through mystical intuition – finally realize their unity with Brahman. This family of views, then, tends to pantheism, the identification of the universe with (part of) Brahman. As Arthur Keith notes in his classic study The Religion and Philosophy of the Veda and Upanishads: "The pantheistic view is undoubtedly present in the many passages in which the development of the world from the absolute [sic] is expressed in metaphors: thus in the metaphor of the spider from which the thread proceeds, or the fire whence come forth the sparks. Often too the Atman is declared to pervade the whole of the universe, it is likened to the lump of salt which in water disappears, indeed, but leaves all pervaded by it [...]." (Keith 1989: 523)

The latter metaphor, of the salt dissolved in water, occurs in the celebrated dialogue of Uddalaka with his son Svetaku in the Chandogya Upanishad: "'Place this salt in the water and come to me in the morning.' Then he did so. Then he said to him, 'That salt you placed in the water last evening, please bring it hither.' Having looked for it he found it not, as it was completely dissolved. / 'Please take a sip of it from this end.' He said, 'How is it?' 'Salt!' 'Take a sip from the other end. How is it?' 'Salt!' 'Throw it away and come to me.' He did so. It is always the same. Then he said to him, 'Verily, indeed, my dear, you do not perceive Pure Being here. Verily, indeed, it is here. / That which is the subtle essence this world has for its self. That is the true. That is the self. That art thou, Svetaku.'" (Chandogya Upanishad: 463)

On Uddalaka's view, then, as the salt pervades the water, so the Atman pervades the entire universe. Brahman qua Atman is therefore not just the efficient cause of the universe but also its material cause, the 'subtle essence' of which everything is made. On the pantheist view, Brahman qua Atman is immanent to the universe. Other metaphors used to express this relation of the Atman to the universe invoke images of production, like sound coming from a flute: "As a spider sends forth and draws in its thread, as herbs grow on the earth, as the hair grows on the head and the body of a living person, so from the Imperishable arises here the universe... As from a blazing fire, sparks of like form issue forth by the thousands, even so, O beloved, many kinds of beings issue forth from the Immutable and they return thither too." (Mundaka Upanishad: 673, 680)

The other strand, associated with Yajnavalkya, stressing the object-less nature of Brahman as pure consciousness, tends rather to acosmism, the view that the existence of empirical reality is no more than an illusion, because in reality only Brahman qua pure consciousness exists. As Keith notes: "The theory which postulated an Atman of no real content [...] was the theory of Yajnavalkya. [I]t lays stress on the three propositions that (1) the Atman is the knowing self, is the subject of cognition; (2) that as such it can never be an object of knowledge of any sort; and (3) that beyond the Atman there is no reality at all, as it is the sole reality." (Keith 1989: 512) It is easy to see that from these propositions it follows that on Yajnavalkya's view reality is at bottom a void, an empty consciousness.

As the subject underlying all cognition, the Atman cannot itself ever be an object of consciousness. Yajnavalkya makes this crucial point in the famous dialogue with his wife Maitreya on the nature and (un)knowability of Brahman: "For where there is duality as it were, there one smells another, there one sees another, there one hears another, there one speaks to another, there one thinks of another, there one understands another. Where, verily, everything has become the Self, then by what and to whom should one speak, then by what and on whom should one think, then by what and whom should one understand? By what should one know that by which all this is known? By what, my dear, should one know the knower?" (Brihadaranyaka Upanishad: 201)

On Yajnavalkya's view, then, the Atman cannot even be described as conscious of itself. The Atman is not self-consciousness but rather consciousness as such, pure consciousness without an object. This is reinforced by the other claim that nothing exists besides the Atman; so in effect there really is nothing for the Atman to be conscious of, since in truth there is no subject-object duality. This leads to the paradoxical result that once we attain insight into the true nature of Brahman, all differentiated reality disappears before our mind's eye as an illusion and what remains is just the reality of empty consciousness. It seems clear that this view, attributed to Yajnavalkya, anticipated much of what Buddhism would later say concerning consciousness and the emptiness of reality.

Later this difference between the acosmic and pantheist strands in the Upanishads became codified in the opposition between the Non-Dual (Advaita) Vedanta of Shankara (ca. 788 – 820 CE) on the one hand and the Qualified Non-Dual (Vishishtadvaita) Vedanta of Ramanuja (1017 – 1137 CE) on the other. Shankara, who accepts acosmism, sees only Brahman Nirguna (i.e. Brahman without any qualities) as fully real, explaining the empirical universe as an illusion (maya) arising from individual ignorance (avidya). As Radhakrishnan dramatically notes: "According to Shankara, it is some monstrous deformity of our vision that makes us see what is really one as if it were many." (Radhakrishnan 1997: 521 – my italics, PS) Ramanuja, by contrast, subscribes to the pantheist view and sees the universe as fully real, explaining it as the body of Brahman: as individual selves stand to their bodies, expressing and manifesting themselves therein, so Brahman stands to the universe as a whole.

Reception of Vedantic Idealism in the West
As noted earlier, the Upanishadic concept of Atman as the Universal Knower is surprisingly close to the Kantian conception of the transcendental subject which underlies and unifies all individual acts of knowledge. It is therefore not surprising that when the first translations of the Upanishads became available in the West during the early nineteenth century, the closeness of the Upanishadic philosophy to the dominant philosophy of the age – Kantian Idealism – was quickly noticed. Schopenhauer, in particular, stressed that the Upanishads had effectively anticipated Kant's philosophy, which in his view "leads to just the same result by a different path" (1958: vol. II, 475). This closeness to Kantian Idealism was also stressed by Paul Deussen, a renowned Indologist and admirer of Schopenhauer. Deussen even claimed that Kant's Critique of Pure Reason gave "the true scientific foundation of the Vedanta system" (1912: 55).

However, this comparison of the Vedanta to Kantian Idealism was not a very happy one. Kant, after all, still retained an unknowable "thing-in-itself" outside of all consciousness; the transcendental subject merely constructs empirical reality by imposing its order (time, space, causality etc.) on the raw sensory data caused by the thing-in-itself. In the Vedanta, however, nothing exists apart from Brahman, the self-causing cause of all reality. So there is no thing-in-itself to occasion the experiences witnessed by Brahman; somehow all these experiences flow from Brahman itself. Thus the Vedanta stands much closer to the post-Kantian Idealisms of Fichte, Schelling and Hegel, who did away with Kant's concept of the thing-in-itself which they took to be illogical. After all, if the thing-in-itself is unknowable, how then can we know about its existence? And if causality is just a subjective form imposed on sensory data, as Kant said, how then can the thing-in-itself be the cause of those data? Hence the rejection of Kant's thing-in-itself by Fichte, Schelling and Hegel. It was precisely this abolition of the thing-in-itself that turned their Idealism into Absolute Idealism, insofar as the transcendental subject remained as the sole existent and sole source of empirical reality, i.e. as the Absolute.

It is true that Schopenhauer, too, rejected Kant's notion of the thing-in-itself as being illogical. But his pessimistic Idealism, where reality is in essence nothing but a "blind Will to Life" which is eternally at war with itself, is a far cry from the Vedantic view of Brahman as supreme bliss – a view that is essentially optimistic. For Schopenhauer, ultimate deliverance meant just the cessation of all willing and thereby of all suffering – an essentially negative doctrine owing much more to Buddhism than to the Vedanta. In the Vedanta, deliverance is a supremely positive experience: participation in the bliss which is Brahman. It is a bit strange, therefore, that insofar as the Vedanta was taken up by 19th century German Idealists, these were primarily Kantian Idealists of a Schopenhauerian bend. To the Absolute Idealists – Fichte, Schelling, Hegel – the Vedanta was virtually unknown (Hegel doesn't even mention the Upanishads in his discussion of Indian Philosophy in his Lectures on the History of Philosophy), even though it fitted their philosophy much better than Schopenhauer's.

It seems likely that Schopenhauer's early appropriation of Indian philosophy prejudiced other Idealists against the latter, as it reinforced the impression that Indian philosophy was essentially nihilistic and effectively coincided with Buddhism. Professional recognition of the closeness of the Vedanta to Absolute Idealism came only during the first decades of the 20th century, notably through the work of Sarvepalli Radhakrishnan, who introduced the Vedanta into the cultural circles of British Idealism (cf. Mander 2011: 537-8). By that time, however, British Idealism itself was already on the wane, due to the onslaught of Analytic Philosophy. The professional recognition of the Vedanta as a form of Absolute Idealism was therefore short-lived: it disappeared from academic view together with Absolute Idealism...

References
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