Human life is a composite continuum of varying phases of consciousness, of different processes of thought. It comprises a few links in the long chain of development, a few rungs in the lofty ladder of evolution. It is a series of conditions, becomings, events, which ever stretch beyond themselves and point to something remote, something wider and yet unattained. Life is, therefore, an ever-increasing organisation of consciousness, never resting in itself, never satisfied, but always hoping to be completed in a state of existence which is dimly foreshadowed in the present experience of the individual. Every condition of experience appears to be real and complete when it takes the role of being the one immediately above that which is directly being experienced in consciousness. It reveals its unsatisfactory character when it becomes the content of immediate experience. Unachieved ends seem to promise fulfilment and perfection, but they become pointers to another unachieved state when they are actually experienced. This shows that life is only a step, a stage, means, and not the final goal, destination or end of endeavour. Every lower stage of life appears to be unreal in a higher stage, though no stage is unreal from the point of view of its own temporary existence. Though all stages are real in a sense, they have differing values, and so we are to admit degrees in reality. The higher includes and transcends the lower; the higher is the fulfilment of the lower, and the sense of satisfaction is more in the higher than in the lower. The aim of life is to experience in immediate consciousness the highest state of reality, i.e., the Ultimate Reality, where all aspirations find their consummation and the supreme purpose of life reaches its realisation.

Philosophy starts with the recognition of the inadequacy of the present state of life. It is the outcome of the discovery that something beyond human life does exist. Dissatisfaction with what is presented to the empirical consciousness is the source of all speculation and spiritual effort. The method adopted in realising the Supreme Being is dependent on the conception of it which one has. The conception of reality is a form of the mental consciousness objectified as the complement of the subjective need or the extent to which incompleteness is felt in the depths of the individual. Thus, conceptions of the nature of reality are bound to differ from one another, as different persons feel dissatisfaction in varying intensities. We have, therefore, to consider the views which directly influence the methods of approach to reality.

Existence and Value

The problem of reality has direct bearing on that of existence and value. Existence is what is independent of everything else, different from relations of every kind. Value is the nature of existence as it is related to a perceiving subject; it is the manner in which an external existence becomes a content of an internal consciousness. An object as cognised or perceived is, therefore, a value, and not an existence as such. But the true nature of the object, without being related to a cogniser, is its existence. The problem of perception involves the determination of the nature of existence and value. For, on this depends the worth of perceptive knowledge. What do we really perceive? Is it only an illusion, an error, or is it a fact in itself? Do we grasp phantoms in sense-perception or do we have real and genuine knowledge of anything truly existent? The investigation of this phenomenon of the relation between existence and value, truth and error, leads one to various kinds of metaphysical and epistemological speculations. The Upanishads synthesise all empirical views of reality, dive deep into the facts of experience and proclaim what is most authoritative, direct and in harmony with the various phenomena of the universe. To understand the exact value of the philosophical position of the declarations of the Upanishads, we may proceed from the first views of things held by those who depend on what is given on the surface of human experience.

Naive Realism

There is a theory which is generally termed naive realism. According to it, what is perceived through the senses is the true nature of the object thus perceived. The datum of experience is identical with the reality that is presented to the perceiving consciousness in the form of the external object. There is no difference between object as perceived and object as it is in itself. The universe of objective perception is really in the very form in which it is experienced through the senses. The universe is material in nature, diverse in form and even mind which is the perceiver is a kind of modification of cosmic matter. This is, in other words, the materialistic view of reality. The great defect of this view is that it cannot account for the fact of error in perception. What is meant by erroneous knowledge? What is wrong perception? Why is it that sometimes we are unable to know things as they are, but are made to take a phantom as the given in experience? How can the perception of water in a mirage be explained, if what is experienced through the senses is the same as what is in fact externally in the world? The theory that reality is material and is as it is experienced individually is untenable for various reasons. That which is really material cannot be assimilated into one's consciousness, and what is thus not assimilated cannot be known by the consciousness on account of there being a gulf between the experiencer and the experienced.

If mind and consciousness are products of matter, they must be inherent in matter. What is not in the cause in some form or the other cannot be produced as the effect. If the cause is matter, the effect also would be matter. If mind and consciousness are facts of experience, and if they are said to be effects, they must have a conscious cause, too. How can something arise from nothing? The attempt to merge the entire individual experiencer in a material universe is bound to end in failure. Epistemologically and metaphysically the theory of naive realism is found to be unsatisfactory on account of its inability to explain facts of consciousness and experience of matter by consciousness.

What is the relation between the experienced object and the experiencing consciousness? Taking for granted that the object is material and is different from consciousness, we would be obliged to fall into a chasm of the unceasing difference between the given in experience and the experiencer. What is it that exists between the experiencer and the experienced? According to crude realism, it can be neither matter nor consciousness. For, if the relation is material, it would be indistinguishable from the object; if it is conscious, it cannot be separated from the subjective experiencer. If it is neither, the relation remains unexplained, unless a purely arbitrary and unwarranted neutral stuff is brought forward as the explanation thereof. If the subject and the object are totally different from one another, there cannot be knowledge. Nor can it be said that the subject and the object are of identical nature, and this nature is material, for materiality being not the same as consciousness, there cannot be apprehension of anything on the supposition that the experiencer is material in nature. Matter is unconscious and it cannot know anything.

Naive Idealism

There is another of reality which goes by the name of naive idealism. It is the view that what is experienced is the same as the real, and that this real is identical with the idea of the individual subject. This is equal to merging the whole cosmos in the idea or the consciousness of the individual. All the substance of the earth and the heavens is my idea; you all are contained in my conception or notion. There is no cosmos independent of the subjective idea. The world is the projection of the experiencing subject.

This view is quite good as far as it is confined to the private reactions which the subject manifests towards the objects of the universe in consonance with the interests which the subject cherishes on account of the presence of various kinds of desires and impressions imbedded in itself. But when this theory is taken to be metaphysical one, i.e., a theory of reality, it falls to the ground. It cannot be said that an individual can perceive external objects even if there is nothing at all outside in the form of some degree of reality. There cannot even be an appearance of externality if there is no support for this appearance. Appearance presupposes reality. Further, it is not true that the individual experiencer has full control over what is experienced outside as the universe. Experience shows that the individual is bereft of knowledge of and power over the vast universe and that the other individuals of the universe are not in any way inferior to their experiencer as far as their status as existence is concerned. All exist in the same degree of reality in a particular plane of existence; otherwise, there cannot be subject-object-relationship. If the subject is more real than the object, there cannot be interaction between the two, and there cannot be knowledge. This proves that the external universe is not subservient to the ideas of the subject. It has an independent reality which no individual can deny. The knower and the known are in the same status, on a parallel basis. There is no difference in degree of truth between the experiencer and the experienced. The theory of naive idealism, or subjective idealism, is not tenable.

Critical Realism

The theory of critical realism is that the percept of the individual is neutral and the real object presented in experience is different from the percept. The datum in experience through the senses is different in quality and reality from the true object which is in the external universe. There is thus a dualism between the actual percept of the senses and the reality behind the sense-experience. There is what is called the universe of the subject and the universe independent of experience by the individual. Reality is not known through sense-experience. What is known is private to the individuals and what is there in fact in the universe is quite a different thing. Reality, therefore, cannot be known through means possessed by the individual. We are given an epistemological trinity and a metaphysical indeterminism. There are some who take this real as material in nature. That the metaphysical reality cannot be matter has already been shown.

Objective Idealism

Objective idealism is an epistemological dualism, and it differs from critical realism in holding that the true object of experience is a Cosmic Mind or Universal Thought. This Universal Mind is independent of individual minds. Empirical perception is the form taken by subjective consciousness, but the reality behind this perception is the Universal Mind. The nature of the Universal Mind cannot be known through individual perception. Reality is different from appearance. It is necessary that the individual should expand its consciousness to universality in order that it may be enabled to experience Reality.

God, the Universe and the Individual

These considerations lead us to the problem of the relation of God, the universe and the individual. It must be remembered at the outset that all processes of reasoning proceed from experience-experience of the individual self. 'I am'-this experience does not require any other proof outside itself. It is self-evident. All proofs are the results of and developments from this indubitable fact. The consciousness of my existence as an individual at once brings into my notion the existence of other individuals in an external universe. 'I am' means 'you also are', i.e., 'the world also is'. The being of the world is the correlative of the existence of my individuality. There cannot be a subject without an object of experience. The world is the necessary implication of the individual.

But the position, as it is known to us, of the individual and the world does not explain all matters that arise out of this position. Thinking beings, capable of reflection, become eager to know the relation between the world and the individual. What is the cause of this world? How am I connected with the other things of the world? What is my duty here? Questions of this kind crop up in the minds of several persons. And these questions cannot be answered by anything that is the content of sense-experience. But the need for a solution of the difficulties that arise out of the appearance of the world and the individual is stringent. The solution can be arrived at by higher synthesis brought about through the deeper consciousness implied in ordinary experience, the consciousness which becomes the direct experiencer in such higher contemplations. The link between the world and the individual should be either of the nature of the object or of the subject. The objective universe is seen to be material, and if this is taken to be the nature of the relation between the world and the individual, it would be another name for another part of the universe. In other words, there would be no such thing as relation. And, at the same time, the zeal with which one identifies the universe with the experiencing consciousness should not lead one to subjective idealism; for the defects of this view have been pointed out. Somehow, we are made to feel that this relation should be conscious, and yet it cannot be identical with the subjective consciousness. The relation between two things cannot be any of these two things. It must be a third thing. Otherwise there would be no perception of difference. Difference is a third category, and there cannot be knowledge of this difference without an underlying unity between the knower and the known. Absolutely unrelated things cannot become correlatives of each other. The higher synthesis which is in consciousness should therefore be transcending the empirical distinction between the subject and the object. The world and the individual should be included in this higher consciousness, and yet, none of these should lose their intrinsic worth in it. If we are able to establish this universal conscious relation between the world and the individual, we have established the existence of God. God is the necessary postulate which alone can explain the true nature of the various phenomena of the universe. The order, the system, the regularity and harmony of the universe cannot find an adequate explanation without the admission of this all-comprehending Being, which we term God. It does not matter by what name we refer to it, but it has to be admitted in order that we may be consistent in our explanation of the consistency that is in the universe. Our deepest reality is an irrefutable consciousness, and it asserts itself in every one of our endeavours to give an account of experience, subjective or objective. Without consciousness, there can neither be a universe nor an individual. Nothing can be, if consciousness is not to be. All value and existence come to a nought when consciousness is abolished from the field of experience. Supreme Intelligence or Consciousness has to be equated with the Sovereign of the Universe-God.

The conception of God in the Upanishads is of special significance. The God of the Upanishads is the Antaryamin, the Indwelling Presence in the Universe. This God is different from the God of the Nyaya and the Vaiseshika philosophies, who is entirely cut off from the universe of manifestation; the God of the Yoga philosophy, who has no intelligible relation to the principles of Purusha and Prakriti, and is not the ultimate goal of the aspirations of individuals; or the God of certain theistic schools, who is different from the manifested universe and the Jivas, though he is considered to be omnipresent and the existence of everything. The God or the Ishvara of the Upanishads is the Absolute-Individual, the only Person or Purusha, whose form is all that was, is and will be, who transcends the threefold time and is beyond spatiality and its concomitants. In this Great God are comprehended the possibilities and the potentialities of all the Jivas; in him are also all the actual forms of the Jivas. He is the Goal of knowledge and power. He is omnipresent, omniscient, omnipotent. He is, to the universe, the highest representative of Satchidananda, Brahman. He is the universe and he is all the individuals. Different from this God, there is no universe, no individuals. Ishvara is Brahman from the cosmic standpoint. Brahman is Reality unrelated. As long as the Absolute is experienced as an object by differentiated individuals, it shall appear as a material universe of changing forms, a not-self contending with the self. Differences cannot be annihilated in individualistic perception. Only the Experience-Whole can reveal the reality of the indivisible Absolute, whose essence and existence is Consciousness, Eternal, without any relation to external appearances.

The Upanishads, it is true, do not give us a systematic account of reality. They are collections of statements of Truth in its various phases. These statements are made not by one but several seers in different Upanishads. We have to study the Upanishads carefully and thoroughly in order to gather a philosophical system from them. It is the genius of Acharaya Shankara that for the first time evolved a consistent system out of the diverse declarations of the Upanishads. It is the argument of Shankara that reason should not be unbridled, but should conform to the intuition expressed in the Upanishads; reason can be made use of till its limit is reached, but beyond this limit the Shrutis or the words of the spiritual preceptor alone are the support. Reason has, therefore, a value, but within certain limits. Tarka (discussion) and Anubhava (experience), Yukti (reason) and Shruti (revelation), logic and intuition, should go hand in hand. As long as it is possible to make use of the power of reason in determining truth, it is one's duty to use it; but when its limit is reached, it should be abandoned. Any further use of it would lead to error and not truth. We cannot conceive of a greater respecter of reason than Shankara, and yet no one could be more conscious of its defects and limitations. Reason and faith in the intuitional declarations together become the royal road to the realisation of Brahman. The lower truths are useful until higher truths are realised. The higher truth includes the lower in a transfigured condition.

An attempt at attaining to the truth of experience takes us through two ideas-the subjective and the objective. The subjective idea considers things as purely mental or idealistic. The universe, according to it, is an externalised form of mind or idea. But, it will be clear that this is not a tenable position. Experience shows that the object of consciousness is not more real or more unreal than the experiencing idea or consciousness. If the idea of the perceiver is to externalise itself as something in the universe, there must be a basis for it. We have objective perception in dream-experience. We have a dream-space, a dream-time and dream-objects. It may be said that all that we perceive in dream is an idea. But, if we critically examine this position, we shall notice that there is something deeper implied in the argument than what is apparent. What is the meaning of dream? It is known that, in dream-experience, there is a dream-subject together with dream-objects. I become the perceiver of the dream-objects in my dream. But is this dreaming individual identical with the waking individual?

I become a subject in dream; and I am a subject in the waking state also. The question that we have to put here is: Is this dreaming individual who is different from the dream-objects the same as the waking individual who is different from the objects of waking experience? If we think carefully over the issue, we will find that they are different from each other. The waking individual contains within himself the dream-subject as well as the dream-objects. It is the waking subject that has externalised his ideas as the dream-subject and his universe. When we wake up we find that not only the dream-universe is not there, but the dream-subject, also, is not there. The dream-subject and the dream-objects are unified in the waking subject. This can give us a clue to the relation of the individual to the universe. Even as the dream-subject is different from the dream-objects, this waking subject is different from the waking universe; but even as the dream-universe is not created by the dream-subject, so the waking universe is not the product of the waking subject. And, even as the subject and the objects in the dream state are resolved into another subject in the waking state, the waking subject and the waking universe are resolved into another subject which is Purushottama or Virat. Ishvara contains in himself all the objects and subjects. The universe is the objectification of the Cosmic or Universal Consciousness, and not of any individual mind.

Ishvara is the Soul of the universe, the Cosmic Self, the Cosmic Mind, who is the efficient and material cause of the individual minds; the individual has no independent existence apart from Ishvara; God includes in himself both mind and matter. Brahman (the Absolute) is Ishvara divested of cosmic relations, and Ishvara is Brahman in relation to the cosmos.

When we started philosophising, we came across three principles-God, the universe and the individual. We have advanced further and have found that God must include within Himself the universe and the individuals. He is not merely a relation, but true existence. He is That which resolves into Itself the universe and the individuals.

But, if, in God, the universe and the individuals are merged completely, why is there perception of difference? I cannot say that I am the same as the world that I see. This question can be answered by making a distinction between the human view of the universe and the divine view. We look at the universe in terms of space, time and causation. The moment we think, we think in terms of these three terms of knowing. Everything is involved in these three links. We imply in the fact of our thinking, our being individuals. We think of something in space; space objectifies experience. When we try to introduce a relation among these principles, i.e., God, the universe and the individual, we have already created difference. The difference implied in their conception is the very basis of our processes of thinking. How can we think of the nature of the Divine Being without objectifying it in space? This is why the Upanishads hold that Ultimate Truth is transcendental. The mind of man cannot think of anything independent of objectivity. This is the fundamental error in human perception. God transcends space, time and causation. In order to think of God, we have to transcend these limiting factors. And we cannot do that. The moment we try to avoid these things, we avoid our own existence. The thinker ceases to exist in the attempt at transcending relativity of perception and experience.

Philosophy leads us up to a certain stage of thinking; not to the Ultimate Truth. Philosophy trains the intellect in order to recognise its own limitations. It can only make us understand how much we can know in the universe and what we cannot know. The limit of the reasoning power is revealed by philosophy. But the Upanishads do not stop there, with mere reason or with understanding. They reveal the relation among the principles of God, the world   and the individual. Only Aparoksha-Anubhava, or immediate experience, can reveal the truth of this relation. It is non-relational experience, without a relation between the perceiver and the perceived. It is not like man conceiving of God, but God knowing that he is. 'I am'-this is the knowledge of God. Here differs the knowledge of God from the knowledge of man. Man knows: 'I am; and others also are'. But God's experience is not like that. When He knows, 'I am', nothing else exists. This 'I' includes everything; there is no space, time or causation for Him; it is pure Consciousness.

The distinction that is ordinarily made between Ishvara and Brahman can be traced finally to the Upanishads. Though the rigid distinction which is made between these two metaphysical principles in the official Vedanta philosophy of Shankara and his followers cannot be found in the Upanishads clearly set forth, there is no doubt that the basis for this distinction is in the Upanishads themselves. Brahman is described sometimes as Purusha-Vidha which can, without difficulty, be identified with the Divine Being constituting the three phases of Ishvara, Hiranyagarbha and Virat. The Upanishads, however, do not show much interest in distinguishing between Ishvara and Brahman, and the reason for this it is not hard to seek. It is our extreme attachmeht to the process of logical thinking that leads us conceive of Ishvara as somehow distinguished from the Supreme Brahman. For all practical purposes, this distinction need not be made, for it is not necessary. To us, who think as individuals situated in space, time and causal relations, the Absolute appears as something which must have some kind of connection with the universe of our experience. We take the universe of objective perception for granted, and then argue that there must be an Absolute beyond the universe. We cannot disregard the universe, for we see it before our eyes and experience it; and we cannot also abandon the Absolute, for without it all experience seems to become self-contradictory and meaningless. We have also to retain our own individuality, for we do not see any difference between our being and our individuality. We want everything, we want also difference, and we want consistency and logical perfection! We are aiming at Truth, but to get at Truth we make use of methods which are inconsistent with Truth. This explains our failure in grasping it in its completeness. The distinctions among Brahman, Ishvara, Jagat and Jiva are not fundamental; they are relative to individual experience. And the Upanishads, which concern themselves with Truth as it is, and not merely with the logical truth arrived at through speculation, would quite obviously not pay much heed to these relative distinctions created by individual experience. When Ishvara is directly realised, and not merely established by reason, it will be found that Ishvara sheds the relative attributes imposed upon him by the individuals and thus coalesces with the Absolute, Brahman. Brahman appears as Ishvara; it does not become Ishvara. And it appears as Ishvara to the Jivas. When Jivahood is transcended, Ishvarahood, also, has to get cancelled, for the latter is only the correlative of the former, and neither of the two can have irrelative existence. The Absolute alone is; Ishvara, Jagat and Jiva are not absolute existence; they are relations within the Absolute, and independent of the Absolute they cannot be. The Absolute is the All. This is the central doctrine of the Upanishads. But this purport does not easily make itself explicit in any of the proclamations of these texts. They are highly mystical, suggestive and intricate in the manner of their expressions. Nevertheless, this is the outcome of their long discourses, when they are well distilled and properly coordinated.