Natural Realism And The Contact Theory Of Perception – Part I

Natural Realism

The author of this wonderful treatise, Chittaranjan Naik, holds an undergraduate degree in Aeronautical Engineering from IIT Madras and a post-graduate degree in Industrial Engineering from the same institute. Despite a sterling professional career in various companies, he quit his job in a quest for higher spiritual pursuits. He chose the path of Advaitic Vedanta. Simultaneously, he involved himself in a deep study of the six traditional darshanas of Indian philosophy along with Western philosophy. With a solid hold on science, western, and Indian thought by way of his unique educational background and specific interests, he comes up with a book which leaves the reader stunned. The book deserves a place in all the library shelves along with the other classics like by Bertrand Russell and Will Durant. He brings out the profundity and richness of Indian thought in a manner which can only bring pride to every Indian of our civilizational heritage. This book on Indian philosophical thought directly challenges the contemporary paradigms in Western science and philosophy. The present series is a humble effort to summarise some of the key points of the book, with the kind permission of the author himself, to prepare the readers to engage with the book itself in more detail.

Bertrand Russell says philosophy as something intermediate between theology and science in his book, ‘History of Western Philosophy.’ Like theology, it consists of speculations on matters where there is still no definite knowledge; and like science, it appeals to human reason rather than to authority of a tradition or revelation. Philosophy occupies thus a No Man’s Land between the definite knowledge of science and the dogma belonging to theology. It exposes itself to attacks from both sides. Philosophy in the western world explain religion, but it takes care not to question the scientific dogma. It always moulds itself to be alignment with science. This overriding principle of philosophical pursuits is typical of Western philosophy.

In contrast stand the six systems of Indian philosophy, the sheer depth, strength, and antiquity of which is completely unknown to most Indians unfortunately. Western philosophers have been either ignorant of Indian thought or perhaps thought that the East had nothing to contribute to philosophical thought. Our colonial consciousness allows to persist with that view. There have been great exceptions of course. Indian philosophy influenced and impressed a few like Walt Whitman, Ralph Waldo Emerson, Voltaire, and Schopenhauer, but this was hardly adequate. Bertrand Russell acknowledged the differentiation between the Eastern and the Western thoughts.

The Indian philosophical system classifies into orthodox or non-orthodox depending on whether they accept the Vedas or not respectively. The orthodox systems include the six systems called Samkhya, Yoga, Nyaya, Vaisesika, Mimansa, and Vedanta. The orthodox schools combine in pairs: Yoga-Samkhya, Nyaya-Vaisesika, and Mimansa-Vedanta. The first element is the practice and the second element pertain to theory. The non-orthodox systems are Charvakism (materialism), Buddhism, and Jainism. In Indic traditions, philosophy never takes a dry intellectual exercise like its western counterpart. Most importantly, philosophy should have ‘soteriological’ power-the power of intense individual transformation from ignorance and bondage to freedom and wisdom. This has been the driving force for Indian philosophy, to reiterate. There is never a sacrifice to reason and experience, but what distinguishes Indian philosophy is that there is no extreme reverence to science. It does not make any attempts to reconcile itself to scientific dogma. In its quest to achieve human liberation, it would get rid of science too if it comes in the way. The strength of Indian philosophy comes from the fact that despite so many scientific advancements over centuries, it has never felt the need to change or adapt new lines of enquiry. We can only rediscover but not reinvent.

Philosophy has engaged with the most engaging questions for humanity. What is my purpose in life? What is the purpose of Universe? What is the reality status of the objects in the Universe? Are they ‘real’ in the true sense of the word or is everything we see a representation and reconstruction in our brains? Is there a God? If so, what is the relation between God and Nature? Does the individual soul exist? How does mind and matter correlate? At the root of all these questions is the most important one of whether Consciousness is primary (the Indian view) or a secondary phenomenon of matter-mind (the Western view). These are some of the quintessential questions of philosophy.

In this book, the author takes up specific and important questions related to the perception process of the external world, the reality status of objects in the world and the mind-matter relationship. He compares Indian and Western thought on these issues, and shows clearly that they are two different paradigms in explaining reality. There is a huge problem of ‘incommensurability’ here which means that the reasoning of one paradigm cannot explain the other paradigm going in a completely different direction. Because Western philosophy honours science without arguing much against it, the Indian paradigms perhaps seem difficult to digest or understand. However, a little thought shows that the answers and the consequences are far clearer. It might even lead to salvation, without even believing in the existence of God. In Indian traditions, even atheism is a route to liberation. Philosophy is not an independent exercise, but intricately weaves itself into the fabric of both science and tradition.

Indirect Realism And Direct Realism

When it comes to perceiving objects in the external world, the standard Western paradigm is that light falls on an object first. This reflected light enters the eyes, falls on to the retina from where neural impulses travel via the nerves to a region of the brain. Here, the image gets a reconstruction, and the person ‘sees’ the object. The same sequence is true for all the other senses too like hearing, touch, smell, and taste. This is the ‘stimulus-response theory of perception,’ a stimulus of some sort evoking a response inside our brains through an intermediate causal chain. Of course, there is a little difficulty in explaining how an internal image inside the brain projects to the outside world.

Hence, in effect, what we perceive in the external world are not as they really exist, but how the interpretation occurs in our brains depending on our endowed senses. This is Representationalism- the perceived world as only an internal representation of an external world; hence, it is an indirect form of reality. What exists outside is never known. What is known is by the reconstruction of neural impulses in the brain. The world outside is not a true world in this sense. In Kantian philosophy, the original unknown is the ‘noumenon’ (in modern parlance- ‘the non-linguistic’ world) and the known constructed reality is the ‘phenomenon’. Representation is the contemporary scientific view and gets the term ‘Scientific Realism’ or ‘Indirect Realism’, and forms the basis of both philosophy and neuroscience.

In contrast, Indian philosophy for thousands of years has been clear on its stand of a ‘Natural Realism’ or ‘Direct Realism’. All the six systems of Indian philosophy with some minor variations propound an active theory of perception where the perceiver is central in the scheme of things. The perceiver goes out and reaches the object in the world. This is the ‘contact-theory of perception’ of Indian philosophy in contrast to the ‘stimulus-response theory of perception’. Contact with the object by the perceiver gives a direct information of the world as it exists. Hence, the external world as seen or heard is an actual world in its reality and not a construction. This establishes the role of pratyaksha or direct perception as a valid pramaana or means of knowledge. This contrasts with Western philosophy where the world can never be known; hence, perception is never a valid source of knowledge in western traditions. This also becomes the driving conclusion of the author in the book.

Western Philosophy And The Problem Of Ontology

Ontology (‘onto’- real or existence; ‘logia – science) studies what is real and what exists. What are the fundamental parts of the world and how are they related to each other? Are physical parts more real than the immaterial concepts, like for example are the physical shoes more important than the immaterial concept of walking? And what exists-the shoes or the walking? Along with metaphysics, ontology deals with questions concerning what entities exist or thought to exist and how such entities group, relate within a hierarchy, and subdivide according to similarities and differences. Ontological studies divide into two groups: one believes that the material processes are real and reality exists independent of the observer; while the other group believes that the immaterial mind and the generated consciousness are the true reality, and the world is a construction in the observer’s mind.

Thus broadly, there are two contemporary philosophical positions with how we perceive and experience the reality. Representationalism (Scientific Realism or Indirect Realism) believes that the perceived world is only an internal representation of an external world; hence, it is an indirect form of reality, because the brain reconstructs the neural impulses impinging on it to create a world outside. The real world remains unknown. Idealism is a variation of contemporary thought that believes that the world we perceive is subjective and mind-dependant. The world has no existence independent of the mind and of our subjective perceptions of the world. In both the above forms, the world is mind-dependent. There is a third position called Realism. Western philosophy has a slightly different meaning for this position. The thesis of the book holds Realism as a position that the world exists independent of our perceptions of them.

If there is a mind dependent world, then what is the ontological status or the true reality of the world? All we ever know are the ‘phenomenon’ with the true ‘noumenon’ always unknown. By the beginning of the 20th century, there was an impasse in the philosophical world, which was the ‘problem of the external world’. The perceived world is the world we are immediately aware of; it is the world we experience and transact with; it is the world we refer to by the language we use in everyday life; and it is a world that appears to be external to us and to be existent independently of our minds. Yet, the externality and mind independence of the objects perceived becomes problematic. What we perceive are secondary qualities, as presented to our sensory faculties and their specific powers. They are not the primary qualities that belong to the objects themselves. All Representationalist systems cannot thus effectively address the topic of ontology (reality) as the real world (noumenon) is always beyond our capacity of comprehension.

The belief that there are some motions in the bodies and in the intervening mediums that carry the data to the sense-organs has logical inconsistencies and conundrums. These motions and transmissions of data through a medium such as space or air would be existing prior to the appearance of the representations. In other words, they are noumena. In which case, how can we speak of the ideas of motion, medium, space, time, and their relations when they are all categories applicable to phenomena? The stimulus-response theory of perception presents a riddle. The riddle will not go away irrespective of whether we believe in Idealism or Representationalism. If, then, we are constrained to speak of the perceived world merely as mind or phenomena and we do not possess the capacity to speak of the real world external to us- noumenon, in meaningful terms, how indeed would we be able to investigate the topic of ontology? In the field of Western philosophy this problem is unresolved to this day.

The Western Response

The response to the impasse came from two different directions: the phenomenogical epoche of Husserl and the linguistic turn in philosophy spearheaded by Frege. The former, through the systematic procedure of ‘phenomenological reduction‘ suspends judgment regarding the belief in the existence of the external world, and examine only the phenomena as originally given to consciousness. The author shows that Phenomenology is not a philosophy, but rather, a science of consciousness with a limited domain of applicability. It fails to address the questions that arise with respect to the central topics of philosophy, namely metaphysics and ontology.

The linguistic turn in philosophy gave birth to the philosophical stream known as Analytical Philosophy. This rejected natural language as a suitable device for providing the kind of clarity and exactness required for philosophical discourses. They attempted to build an alternative ideal language embodying a specially devised notation with precisely defined meanings and rules for its use and manipulation. This would avoid the errors of the past philosophers. The author calls Analytic Philosophy as a ‘horse with binders’ approach as it focuses on narrow topics while ignoring the broad topics. Neither the incorporation of mathematics nor the development of a powerful logical technique seems to have enabled Analytic philosophy to solve the problem of showing how objects may be mind-independent.

Requirements To Explain The Reality Of  The World

There are certain requirements for contemporary paradigms with relation to explain the reality of the world. The first is the relation between mind and matter. This has again occupied Western philosophers since Descartes’ conception of reality as a duality comprising mind and matter in which the two were disparate kinds of things. For Descartes, mind was a thinking kind of thing and, matter an extended kind of thing. What is their correlation?

Idealism seeks to overcome this problem by denying the existence of matter altogether and holding that matter is nothing but mind. Only the mind exists and the sensation of an outside world, when nothing exists at all, is only because of impulses generated internally in the brain. Physicalism attempts to overcome the problem by reducing mind to matter; and thereby avoiding having to treat the mind as an independently existing thing. In both these cases, there is reduction of one kind of thing to another kind of thing. But reduction is not the solution to the problem; it is a semantic conflation, that is, a conflation brought about by taking the meaning of one word for the meaning of another; and such semantic conflation amounts to a cognitive error. An investigation into reality must therefore strive to resolve the problem of mind and matter without resorting to reduction.

Secondly, the distinction between perception and hallucination needs clarity. There should be an assurance that the perceived world is existent unlike the things seen in an illusion or a hallucination which merely seem to be existent. If we are to undertake a meaningful investigation into ontology, the distinction between perception and hallucination needs grounding in ideas of mind and matter; perception as objective and mind-independent; and hallucination subjective and mind-dependent.

The theory of perception today as a stimulus- response system from the external object to the mind is incoherent in explaining the ontological status or reality of the world. If there is an unknown ‘noumenon’ and a representative ‘phenomenon’, then every object in the causal chain from the external world to the perceiver, including the intervening medium is unknowable. Even the brain is a noumenon because we see it. What is the truth status of our body and the sense organs? This logical extension of the current thinking leads to conundrums and inconsistencies. Some have undertaken a Direct Realism philosophy to sort the problems, but leaving the prevailing stimulus-response theory of perception unquestioned. A stimulus response theory is simply incompatible with Direct Realism. An indirect theory of perception (a physicality theory) can never achieve a transparency due to the transforming nature of the operations of the physical causal intermediaries. The brain-in-a-vat hypothesis in which there is no need of an object at all in an ‘external’ world for the phenomenal object to appear is an extreme but logical extension of the Representationalism’s proposal.

Attempts for Direct Realism and The Time-Lag Argument

Contemporary philosophy has tried to formulate theories of Direct Realism, where the perception of the world is as it is. There is no transformation of the object by the intervening causal chain of intermediaries. This ensures that there is a complete transparency of everything in between from the perceiver to the external object. The perception of the object is in its raw, original, and true form. In contemporary philosophy, the thesis that stands by such a strong form of Direct Realism is Disjunctivism. However, the Disjunctivist makes no attempt to provide an explanation of how the objects seen in a perception may be the same as the objects that exist in the world. The naïve assumption Disjunctivism makes that they are the same makes it a form of Naïve Realism.

The strongest objection to any conception of Direct Realism comes from science; and this at the core of all contemporary philosophy’s rejection of Direct Realism- Western or Indian. This is based on the time-lag argument, which goes like this: There exists a time interval between the reflection or emission of light from a physical object and the light reaching our sensory apparatus, so considering that (i) perception involves a long and complex causal series of events, and (ii) that the object itself may not be existent by the time the reflected light reaches us and gets processed through the causal chain, what is perceived must be something other than the object. One might be seeing a distant star today in the skies which might have completely disappeared millions of years ago. The famous physics example often quoted to explain this time-lag is if the sun completely disappears from the skies, a person on Earth would realize it after eight minutes or so.

So, given that these causal intermediates are present, irrespective of whether the percipient has prior awareness of them or not, what is it that assures the Direct Realist that the percipient directly perceives the object exactly as they are? The finite light velocity is an obstacle in explanations for any direct realism. The Disjunctivists are unable to counter this. This is because a good and cogent defense of Direct Realism is impossible if the stimulus-response theory of perception remains intact, says the author. Direct Realism is incompatible with the stimulus-response theory of perception, and this is the incommensurability problem. They belong to two different paradigms, and one paradigm cannot judge the truth value of the other with its rules and concepts. The implications of the categorical divide in the form of phenomena and noumena that the stimulus-response process of perception invokes has resulted in only confusion rather than solutions.

Refutation of Representationalism and its Variants

Most contemporary philosophers think it foolish to doubt the role of the physical process-chain from the external object ending with the physical brain as the main cause of our perceptions and motor abilities. Representationalism leads to contradictions and logical conundrums. The logical conundrum is because the brain is also a perceived object as are other objects of the perceived world. There must be hence a ‘noumenal’ brain too for the ‘phenomenal’ brain; and there must be ‘some processing mechanism’ presenting the phenomenal brain to us; the original existing in the unknown realm. This postulation of a processing mechanism simply leads to a situation of going one step backwards. The processing mechanism has now another ‘noumenal’ and ‘phenomenal’ attributes with respect to another processing mechanism. Such steps all the way back to infinity leads to a situation of a reductio-ad-absurdum. It is thus difficult to conceive an end point ‘processing mechanism’ as the final percipient which lies outside the phenomena of all representations.

It is not only the external object which has the ‘noumenal’ and ‘phenomenal’ attributes; the real and the represented respectively. Every single aspect in the chain of transmission of information- the medium like air, water; the sensory organs; the nerves carrying the information to the brain; and the brain itself also lie in the perceived world. The transforming mechanisms of the noumenon into phenomenon also have these two attributes. How can one be then so sure of the transforming chain as ‘real’? It is only a presupposition.

When the objects and events in the noumenal external world are not perceivable and non-cognizable, how can we ever infer that the objects and events seen in a perception are reliable indicators of the existence of objects and events in an external world? Thus, the stimulus-response theory of perception, which purports to explain how we perceive objects, ends up postulating that we do not perceive objects at all, and indeed logically leads to a position in which objects would be entirely imperceptible.

Correlation Is Not Causation and The Falsifiability Criteria

There are correlations between brain processes like neurological impulses and brain waves and the individual’s perceptions. This is a proof to substantiate the stimulus-response theory, claims contemporary paradigms. The author says that this position is faulty as correlation does not equate to causation. This, because both the brain-processes and perceptions are ‘phenomena’. The correlation established between brain-processes in an individual and the changes that take place in the individual’s perceptions cannot form a ground for inferring that the brain is the primary cause of perception.

Moreover, the belief in the stimulus-response theory of perception, and the notions of the phenomenal world and noumenal world that it leads to, makes the theory of perception itself into a superfluity in as much as all the prior stages of the imagined noumenal causal chain of processes leading up to perception can be dispensed with; and the explanation for perception can be provided merely by considering them as representational states of the (noumenal) brain alone. Indeed, considering the law of parsimony, it would be more reasonable to accept the brain-in-a-vat hypothesis as the explanation for perception than to posit an entire chain of causal processes. This serves in explaining perception in a needlessly cumbersome manner.

Moreover, the proponents of Scientific Realism hold that a scientific proposition must have a falsifiability criterion. In the case of the claimed division between phenomena and noumena, there is no criterion by which it can be empirically falsified. Thus, as measured by the yardstick of science itself, the proposition is unscientific and accorded the status of a superstitious belief. The division of phenomena and noumena, or phenomenal-objects and things-in-themselves, is an imaginary division not sustainable through empirical means nor through reason.

The Intentionality Theorists, Computers, and Artificial Intelligence

The Intentionalists, another variant of the Representationalists, say that the representational states or cognitive activity in the physical brain are like that in computing machines. But, even in the case of computing machines, what exists in them are mere physical states and not representations, and these physical states attain the status of representations or activities only because of conscious agents. It is meaningless to speak of the representational state as something deployed in nature independently of conscious agents. To superimpose arithmetic activity, logical activity, or some other form of cognitive activity, which exist purely in the minds of conscious agents, onto the physical system and to believe that the physical computer system itself engages in cognitive activity is nothing short of delusion.

There can be no cognitive activity in a computing machine because it lacks the essential characteristic that makes for a cognitive activity- self-awareness. Self-awareness is the distinguishing principle that distinguishes a cognitive activity from a physical activity. Therefore, the physical processes in a computer, even if they seem to exhibit the external behavior of human beings, are not cognitive activities; they are merely simulations, or appearances, of the external behavior of conscious beings.

The Intentionalist’s thesis, which holds that representational states can be in purely physical substrates without the presence of conscious agents, or that cognitive activity can take place in the physical brain as it takes place in a computing machine, has no reasonable basis. The intentionalist’s explanation of perception fails to account for its essential character-self-awareness. The intentionalist might argue that consciousness or self-awareness along with other features of perception, emerges from brain-processes as a secondary phenomenon (an epiphenomenon). In which case, all the arguments against representationalism would become applicable to intentionalism too.

Refutation of Idealism

There are three important concepts in philosophy: the soul, the matter, and the mind. The soul is also the perceiver or the consciousness which has the important property of self-awareness. It is also the sense of ‘I’ in every person. The ultimate question is philosophy is whether consciousness is primary or secondary to other processes. Indian traditions are clear about the status of consciousness as primary; and Western philosophy considers it secondary. Western philosophy does away with the soul and considers mind and matter alone. The only trouble is trying to correlate them. One group reduces everything to matter; with the brain, mind, and later consciousness emerging consequently as epiphenomenal processes. The other group, calls everything as mind, and matter becomes an outcome of this mind. The matter and the universe are only representations of some form in the mind. The latter philosophy, as we saw before, is Idealism. In the Indian tradition however, the two things which exist are the soul (purusha) and matter-mind (prakriti). In the Indian tradition, mind and matter are the same. There is no differentiation and there is no reduction of one to the other.

The Idealists posit that all matter is finally the mind; and the world becomes mind-dependant, like in a dream. Idealism is quite old in Indian traditions. Indic tradition in the course of the historical debates between the Nayyayakas and the Bauddha Idealism has refuted at length Idealism. The knowledge that dream-objects are just creations of the mind is based on the mind-independent structures of objects, and the impossibility of these objects from accommodating within the space of the body. Thus, there is a negation of the reality of the dream object. The dream world is sublated by the waking world.

A dream or a hallucination is sublated by the waking state world which shows that the former is mind-dependent. Similarly, a mind-dependent world of the waking stage would need in theory a sublating knowledge in the existence of a parallel mind-independent world. Thus, the sublating knowledge would reveal a world of real objects whose forms the objects seen in the current waking state would be mimicking. The sublating knowledge would, while showing the world perceived currently to be mind-dependent stimulations, invoke a parallel world of real mind-independent objects. We do not have any evidence of such parallel worlds. String theory shows maybe such parallel worlds; but the theory itself suffers from the lack of ‘falsifiability’ criteria required by science.

Empirical Evidence from Science

There is a strong tendency and dogma among many contemporary philosophers to give pride of place to science. The physical sciences deal with the physical world which constitutes the field of the perceived. Whereas, the theory of perception does not deal with this field but to the process of perception of this field by our sensorium. Representationalism would superficially appear to be a natural consequence of the stimulus-response theory. However, it turns out to be problematical, because it invokes the perceived world as a representation of a delusional non-existent ‘real world’, which, on examination, turns out to be nothing more than an illusory reference conjured up by an illegitimate verbal construction. Yet, philosophers, in general, continue to espouse the stimulus-response theory of perception because it happens to be the theory supported by science; and science has shown a correlation to exist between brain-processes and our perceptions of the world. Philosophers today have succumbed to the inducements of science without labors to examine its foundations with the acuity that philosophy demands. The result is a kind of belief reflected in Will Durant’s words who thought ‘philosophy may blithely allow itself to be led by the hand of science.’

In the context of the theory of perception, there are two claims that it would be mandatory for us to examine; these are: the claim of a correlation between brain processes and our perceptions of the world; and the claim of a time-lag between the occurrence of an event in space and its perception by a human observer. What science has done is to merely locate the processes of the specific organ in the human body which exhibits a correlation with the altered state of perception.

In the next part, we will see how the Indian philosophy seeks to offer a counter-narrative and give an alternative explanation to reality. Direct Realism of Indian traditions most importantly contend that no time-lag exists; and that the claimed observations of the time-lag have all been theory-laden with the presumptions implicit in the theoretical framework of science itself. Direct Realism contends that the time-lag does not pertain to the time taken for light to travel from the source of light to a human observer; it pertains to the time taken for light to travel from the source of light to an object that gets illuminated by the source of light; such an object may be a measuring instrument.

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