Author: Gbenga, Fasiku
Date published: September 1, 2011
This paper elucidates the hard problem of consciousness. There is a prevalent assumption that the fact that a mental experience has a phenomenal property is an ontological fact and that the problem of explaining the phenomenal property of a mental experience is an epistemological problem. Contrary to this assumption, the paper argues that the fact about phenomenal properties of mental experiences is wholly epistemological. Hence, the problem of explaining phenomenal properties of a mental state is not a metaphysical problem, and what is considered a hard problem of consciousness is due to human reasoning process rather than an ontological process.
When I see a rose, there are some light-rays emitting from my eyes in the direction of the rose, producing an image in my retina. The visual systems are psychological properties that caused me to see the rose, and these psychological properties are explained by the cognitive sciences. Apart from these, there is the feel of seeing a rose; the Svhat it is like to' see a rose. So, seeing a rose is one thing, the feel of seeing the rose is another. Again, if I smiled, there are physiological activities (categorized as the psychological properties) that took place that explained the event. Moreover, there is a feel of smiling; the Svhat it is like to smile'. The mental experience of seeing a rose and smiling are perceptual and physiological processes, which are explainable in cognitive sciences through the paradigms of visual and physiological sciences. However, there is a problem explaining what it feels like to see a rose and what it feels like to smile, which are the phenomenal properties of the mental experiences of seeing a rose and of smiling. The need to explain the phenomenal properties of mental experiences is described as the hard problem of consciousness.
The Easy and the Hard Problems of Consciousness
David Chalmers distinguished between two aspects of the mind. These are the psychological aspect and the phenomenal aspect. 1 In the psychological aspect, the mind is the internal mechanism or system which serves as the causal and explanatory basis of human actions, experiences, thoughts, beliefs, actions, etc. In this respect, mental states are those states of the mind that are causally responsible for behaviour, experiences, thoughts, beliefs, actions, etc and through which they are explained. Moreover, in the psychological aspect, the mind is construed as, and is understood in terms of, what it does. This, however, did not reveal the nature of the mind and its states. Rather, the cognitive science' account of the mind, which is the psychological aspect, reveals what the mind does, and not what the mind is. On the phenomenal aspect, the mind is conceived not as what causes or explains experience, but as the experience itself. This experience is qualified as conscious experience, phenomenal consciousness or qualia. Conscious experiences are the properties of our mental states. They are the properties of a mental state, and it is instantiated as a 'felt' quality. The mind is characterized by the way it feels, and what it means for a mental state to be phenomenal is for it to feel a certain way.
There are problems associated with each aspect of the mind. For the psychological aspect, part of the problems is to explain what the internal basis (i.e. the causal processes, activities and properties) of behaviours are, and to explain how the states of this causal mechanism or process produce behaviour. For example, in an attempt to explain an experience of seeing a rose, all that is necessary is to specify perceptual properties and processes in the human being that culminate in the perceptual experience of seeing a rose. These include explaining how some photons strike the retina, how some electrical signals are passed from the optic nerves to different areas of the central nervous system. All of these constitute the causal explanation of the mental experience of seeing a rose. This is all that psychologists, neuroscientists, and neurobiologists would offer as the explanation of the mental experience of seeing a rose. This is an objective explanation verifiable through experimental apparatuses and processes. Given a relative knowledge of neurophysiology, neuroscience and molecular biology, it is feasible to understand, explain and even predict the structures, activations and operations of the peripheral nervous system, the central nervous system, the cortex, the neurochemicals and as well as the other components in the human body, that culminate in the mental experience of seeing a rose. Hence, questions such as ???/ does the brain process environmental stimulation like a rose?' THow does it integrate the information received through the nerves in the human body?' can be answered in terms of specifying the causal activities and processes of the organs and properties in the human body. There could be disagreements about the nature and function of the organs and properties in the body; about how the organs and properties play a causal role in the production of behaviour. These disagreements are resolvable within the cognitive and physical sciences. It is on the basis of this that problems associated with the psychological aspect of the mind are, for David Chalmers, the easy problems of consciousness.2
On the phenomenal aspect of the mind, the mind is not construed as what it does, but as the feel that accompanies mental states. This is the subjective quality, the 'what it feels like to see a rose', attached to the mental or perceptual experience of seeing a rose. This feel is the conscious experience. This conscious experience is also known as the 'phenomenal consciousness', 'qualia', 'what it is like to be', 'raw feels', etc. The question is, just as we can specify the mechanisms or systems, the properties and processes, etc of the perceptual experience of seeing a rose, can we specify the mechanisms or systems, the properties and processes that explain phenomenal consciousness of the perceptual experience of seeing a rose? Why does a particular phenomenal consciousness accompany a given mental state (e.g. a particular perceptual experience) rather than a different one? This is a problem. According to Chalmers, "the problem of explaining these phenomenal qualities is just the problem of explaining consciousness. This is the really hard part of the mindbody problem."'3 Parts of the questions to be answered in addressing the hard problem of consciousness are: What are conscious experiences? Do they exist? How are they produced? Could they be products of the causal activities or processes or properties? As Joseph Levine clearly puts it, the fundamental sets of questions that need answer are: "Do the features that distinguish minds from everything else in nature mark a fundamental division between the natural, or the physical, and the non-natural, or the immaterial? Are we, and the phenomena that constitute our mental lives, an integral part of the natural, physical world, or not?"4 For instance, just as there are physiological and morphological properties, processes and activities that explain the mental experience of smiling, are the raw feels of the mental state of smiling, the what it is like to smile, in anyway explained or explainable through the physiological and morphological properties, processes and activities? Are Svhat it feels like to smile' parts of the edifice of the natural world which can be studied objectively?' These questions introduce what, in the Philosophy of Mind, is called "The Hard Problem of Consciousness.
Further Arguments to Establish the Hard Problem of Consciousness
The hard problem of consciousness is centered on two fundamental issues. The first is to determine the ontological status of phenomenal consciousness or qualia: What are qualia?' TDo qualia exist?' What conditions give rise to qualia?' 'Are these conditions open to empirical investigation?' 'Are qualia predictable and explainable within the purview of an objective and scientific study provided by the physical sciences?' The second issue is to explain why and how a particular mental experience is accompanied by some particular qualia that it has, rather than the other. Put in another words, the hard problem of consciousness is in two strands. The first is the need to justify the possibility or otherwise of separating consciousness and its properties, such as phenomenal consciousness or qualia, from the central nervous system and its properties like the nerve impulses, information processing, neuron firing, and other activities. And if the separation is possible, then there are two kinds of things: consciousness (and its properties) and central nervous system (and its properties). The questions that arise are: What is each of these phenomenon?' and ??\? can each of them be known?' The second is to answer the question, What is the relationship between the two possibly separate phenomena? In other words, given the scientifically observable explanatory apparatus through which the central nervous systems and its properties are explained, it is not all obvious HOW and WHY, within that apparatus, we can account for the causal character of the relation between the activities, processes and properties in the central nervous system of a particular mental state and the phenomenal consciousness that accompanies such mental experience.
As at 2003, Robert C. Coghill, et al, had reported that "no study to date has identified the neural correlates of an individual's subjective experience of pain and characterized them in relation to those of other individuals receiving exactly the same stimulus"5. Also in 2009 Coates and others are more specific in declaring that there is a mystery of conscious experiences, which contemporary scientists still cannot explain. Coates explains,
when we see a sunset or hear a symphony our sense organs, brains and bodies are moved in ways that are well understood by the physical and biological sciences. But during such experiences we also enjoy distinctive forms of conscious awareness. Yet this undeniable fact about our conscious lives is stubbornly resistant to scientific understanding. How is it even possible for purely physical brain activity to produce conscious experience? How do the qualities that manifest themselves in experience relate to the very different properties that are referred to in scientific descriptions of the physical world?6
Put in another way, the hard problem of consciousness is the need to answer the questions: Svhy and how does a given physical process generate the specific experience that it does?' Why, for example, does a physical process in the brain produce an experience of redness rather than greenness? What really defines the hard problem of consciousness is the need to account for the causal relationship between the physical properties and processes in the central nervous system and the properties of mental states called 'phenomenal consciousness'.
The hard problem is, however, not entirely new in philosophy. It is widely accepted that consciousness poses a special explanatory problem for science. This is because the problems related to the structure and the causal interactions of matter and physical (entities and properties), and their implications for understanding of macroscopic and microscopic structural levels and phenomena are successfully scientifically resolved during past three centuries of explosive development of natural sciences. However, the problem of how consciousness evolves has remained scientifically unresolved.7 This same sentiment was entrenched in the writings of the 17th century writers as exemplified by John Locke. He claimed that there is a clear distinction between the quantifiable and objectively identifiable features of reality, such as bulk, figure, motion, etc., and the conscious ideas we experience of those features of reality8. For Locke, the quest to establish a connection between the two is really a difficult task to accomplish. It is this quest that still subsists, and is redefined as the hard problem of consciousness. Locke's pessimism had, in the 19th century, been taken a bit further by a biologist, Thomas Huxley, who asserted that the hard problem of consciousness is an enquiry into Tiow it is that anything so remarkable as a state of consciousness comes about as a result of irritating nervous tissues, is just as unaccountable as the appearance of Djin when Aladdin rubbed his lamp"9
In the contemporary literature, discourses on the Hard Problem of Consciousness raise the same issues. For example, in David Chalmers' view,
Consciousness is the biggest mystery. It may be the last outstanding obstacles to our quest for a scientific understanding of the universe... We have good reason to believe that consciousness arises from physical systems such as brains, but we have little idea how it arises or why it exists at all. ... We do not just lack a detailed theory; we are entirely in the dark about how consciousness fits into the natural order. 10
According to Chalmers, a theory of consciousness should explain the conditions under which physical processes give rise to consciousness. The theory should explain how it arises, so that the emergence of consciousness seems intelligible rather than magical. In the end, Chalmers says "we would like the theory to enable us to see consciousness as an integral part of the natural world. Currently it may be hard to see what such a theory would be like, but without such a theory we could not be said to fully understand consciousness."11
McGinn also expressed the same worry when he asks 'how technicolor phenomenology can arise from grey soggy matter?' McGinn puts the question more succinctly by saying:
how could the aggregation of millions of individually insentient neuron generate subjective awareness? We know that brains are the de facto causal basis of consciousness, but we have, it seems, no understanding whatever of how (and why) that can be so. It strikes us as miraculous, eerie, even faintly comic. Somehow, we feel the water of the physical brain is turned into the wine of consciousness but we draw a total blank on the nature of the conversion.12
In a more explicit manner, Michael Tye introduces the hard problem of consciousness by asserting that "we are all material beings. But we are also being who have experiences and feelings. We perceive things with our senses, and in so doing we undergo perceptual experiences; we have bodily sensations; we feel a variety of emotions and moods. These things are subjective, or, at any rate, they have a subjective side. How can they just be a matter of matter?"13 Moreover, the pessimism about a successful physicalist or materialist explanation of consciousness is forcefully expressed in Jerry Fodor's view. For him, "nobody has the slightest idea how anything material could be conscious. Nobody even knows what it would be like to have the slightest idea about how anything material could be conscious". 14 Thomas Nagel, had been inclined to believe that the problem has no solution. According to him, "the subjective features of conscious mental processes - as opposed to their physical causes and effects - cannot be captured by the purified form of thought suitable for dealing with the physical world that underlies appearances."15
The Hard Problem of Consciousness; a Phenomenal of the Noumenal
While appropriately designating the hard problem of consciousness is an epistemological rather than a metaphysical problem, in explaining the details, John Searle and Joseph Levine assert that it is a matter of fact that brain processes cause conscious states, but what we do not know is how physical processes cause conscious states. 16 According to John Searle, the question of *what' caused what is metaphysical and the question of how it is caused is epistemological; the former is not problematic, it is a matter of fact, but the latter is a problem. In the same vein, Joseph Levine argued that two sorts of explanation can be given of the relation between mental states and their qualitative characters. The first is a metaphysical explanation and the second is an epistemological explanation.
On the metaphysical side, to say that phenomenon A is explained by B is to say that B is responsible for A. The sense of 'responsibility' at issue may be causal, or it may be some other relation that fits under the heading 'in virtue of.' The point is that it is in virtue of B, because of B, that A occurs. On the other hand, to say that A is explained by B can also mean that by appeal to B we can understand, or make intelligible, why A occurs. Of course these two sides to explanation are related, since appealing to what is responsible for A is a way of making intelligible why it occurs, but nevertheless they are not the same thing. 17
Answer to the question - what explains the qualitative character of my sensation when I look at a rose?' - may very well be the physical properties of the brain states. If this is so, the question could then be addressed in some sort of biological and neurobiological theories. But, according to Levine, "what causes a problem is that appeal to these physical properties does not explain the qualitative character in the epistemological sense - it does not provide understanding of why there should be the reddish quale that there is."18 Thus, Levine assumes that it is an ontological fact that the physical properties of the brain states cause qualitative character of mental states.
Contrary to the assumption expressed by Searle and Levine shown above, we would argue that the relationship between the qualitative character of a mental state and the physical properties of the brain states is due to human description, therefore facts about the relationship are wholly epistemological rather than being metaphysical. In fact, we would argue that the assumption that a qualitative character accompanies a mental state is based on a belief about what exists in the world, and that such a belief needs further justification.
There are two conceptions of metaphysics. The first is that metaphysics is an enquiry into the nature of reality. In this sense, metaphysicians examine reality as it is and derive facts about its structure, scope and order. The second conception is that metaphysics is a self-reflective exercise that seeks to gain an understanding about how we (human beings) represent facts about reality to ourselves. 19 In this sense, the concern of metaphysicians is about how our conceptual and semantic schemes structure our minds and thoughts about reality. In other words, the concern of metaphysics is not about reality as it is, but about the relationship between our conceptual and semantic schemes and reality. This conception of metaphysics exemplified what is identified as descriptive metaphysics (in which metaphysics is merely a description of 'the actual structure of our thought about the world^, while the first conception of metaphysics fits into what is identified as real metaphysics (in which metaphysics is an attempt to describe the actual, fundamental structure of the world). 20 The difference between the two conceptions of metaphysics is that in the first conception, metaphysicians examine and derive facts about the nature of reality as it is. This means that reality as it is is one thing, and the facts about it, derived and subjected to examination, is another. In the second conception, metaphysics is concerned with reality as it is presented to us through our conceptual and semantic schemes. This means that the relation of human beings with reality as it is is mediated by human conceptual and semantic schemes. What comes out of the two conceptions of metaphysics is a reminiscent of Kantian distinction between noumena (things in themselves) and phenomena (empirical objects)
What tied the two conceptions of metaphysics together is that reality as it is exists unmediated, and metaphysicians construe it as facts either derived through or mediated by our conceptual schemes. Thus, there are two kinds of reality: reality as it is and reality as derived or represented by conceptual schemes.21 In a sense, it is correct to argue that the latter is also a part of the former. This is because the derived facts about reality and the reality represented by conceptual schemes both exist in the 'underived' and 'unrepresented' reality (i.e. reality as it is). It is in this sense that Tienson is correct to affirm that "there is a world, and our thought about it is but part of that world. Any complete philosophical position must tell a story about the structure of our thought, a story about the wider world of which that thought is a part, and a story about how the two are related."22 This implies that there is the way the world is, which is independent of any derived facts, conceptual representations, thoughts etc, and the emotional approval or otherwise of derived facts and conceptual representations.23 However, it is important to point out that Tienson's distinction between the wider world (reality as it is) and a story about the structure of our thought about it did not clearly demarcate the world as it is from thoughts about the world. This is because a story about the wider world is a story, it is an account of our conceptual schemes about the world; and it is possible to separate the story from the object of the story. In this case, the wider world (reality as it is) is the object of the story. What could be implied is that there can be no wider world (reality as it is) independent of our thought, story, or conceptual schemes. This shows that the only reality is what thoughts or conceptual schemes say it is.
What derives from the above is that the claim that mental states are accompanied by some qualitative properties is a fact derived from the world as is it. This claim is parts of our conceptual schemes about the reality as it is. Given the understanding of the phenomenal properties of mental experiences as a purely qualitative, non-conceptual element in human consciousness: a feeling in itself; and as one which we have no epistemic access24, it is correct that our beliefs and assertions are subject to error and requires some kind of justification. So, to assert that that the feeling in itself or phenomenal consciousness accompanies mental states is not to be taken as a matter of fact but a mere report about how things are in the world. The possibility that things could have been different from this, or that the mental states may have been accompanied by other properties other than phenomenal consciousness or raw feels, suggests that it is open to debate whether it is a fact or not that in actual reality, in reality as it is, mental states are really accompanied by qualitative properties. What this shows is that claims about the nature of qualitative properties (also known as phenomenal consciousness, qualia, raw feel, conscious experience, etc) are mere epistemological claims, which are subject to systematic error. More important, just as the hard problem is correctly asserted as an epistemological problem of how and why do qualitative properties accompany mental experiences, the above shows that it should be correct to assert the claim that mental experiences are accompanied by qualitative properties is also an epistemological claim rather than a matter of fact.
The implication of this is that the hard problem of consciousness is stressed backward to cover the claim that mental experiences are accompanied by qualitative properties. The question is how do we know that this is a true reflection or representation of how things really are in themselves? In other words, quests to resolve the hard problem of consciousness should be start by answering the initial question of whether mental states are indeed accompanied by qualitative properties. Hence, the question that characterized the hard problem of consciousness: questions such as how and why qualitative properties accompany a particular mental state, is a further question. The initial question is, 'is it true that mental states are accompanied by qualitative properties?' Answering this question requires a beep into reality as it is, and this beep cannot provide an indubitable feature of reality as it is, so, whatever is asserted as the relationship between mental states and qualitative properties is an account of reality in itself, and questions ranges on how to authenticate this account. The need for this authentication may be considered a harder problem of consciousness.
The current discourse in the Philosophy of Mind centered on what is called the hard problem of consciousness. In this paper, it is argued that the hard problem of consciousness should be preceded by the need to justify the claim that, in reality, a mental state is accompanied by some qualitative properties. It was shown that rather than being a matter of fact, the claim that a mental state has some raw feels attached to it, is a belief, an account of the conceptual scheme or a story about reality as it is. This proven, the paper strengthens the assertion that the hard problem of consciousness is an epistemological problem. But, more important, we reject the assertion that there are facts about the relationship between mental states and the qualitative properties that allegedly accompany them are ontological fact. We argue that this assertion is just like any other epistemological statement and its truth needs to be justified. Indeed, the search for such a justification is, in our opinion, a harder problem of consciousness.
1 David J. Chalmers, The Conscious Mind: In Search of a Fundamental Theory. Oxford: Oxford University Press, 1996, pp. 30-31
2 On Chalmers's view, the easy problems are easy because they ask for no more than an explanation of various cognitive functions - and explaining any sort of function is something that science is well suited to do. Once the relevant mechanisms are well understood, there is little or no explanatory work left to do. Although experience is associated with a variety of functions, explaining how those functions are performed would leave important questions unanswered. We would still want to know why their performance is accompanied by experience, and why this or that kind of experience rather than another kind. So, for example, nerve stimulation and nerve damages could be the mechanisms that play the causal role of pain, and these mechanisms cause recoil and avoidance. Explaining these causal mechanisms could possibly be done by studying the essential nature of nerves, and find out what happens when nerves are stimulated, or damaged. This inquiry is best suited in the cognitive sciences. This is why the problem of explaining causal mechanisms is easy.
3 David J. Chalmers, The Conscious Mind, p.4
4 Joseph Levine, Purple Haze: The Puzzle of Consciousness. Oxford: Oxford University Press, 2001, p.4
5 Coghill Robert C, McHaffie John G., and Yen Ye-Fen, "Neural Correlates of Interindividual Differences in The Subjective Experience of Pain". Proceedings of the National Academy of Sciences (PNAS). Volume 100, Number 14, 2003.
6 This is the basis of a three-year research project being embarked on by a team of University Hertfordshire philosophers led by Professor Paul Coates and Dr. Sam Colemaa For details, see Science Daily, January 26, 2009, "Researchers Explore What Contemporary Science Cannot Explain." Retrieved April 7, 2009 from http://ww.sciencedailv.com/releases/2009/01/090123075632.htm
7 Dejan Rakovic and Djuro Koruga, Consciousness, Scientific Challenge of 21a Century, Belgrade: European Centre for Peace and Development (ECPD) of the United Nations University for Peace, 1996, p. i
8 John Locke, An Essay Concerning Human Understanding , Chap IV, iii, 28, Oxford: Clarendon Press, 1979, pp. 558559
9 Thomas Huxley, 1866, 8, p.210, quoted by Michael Tye, Ten Problems of Consciousness, Cambridge, M.A.: The MJT Press, 1995, p.15
10 David Chalmers, The Conscious Mind: In Search of a Fundamental Theory, Oxford: Oxford University Press, 1996, p.15
11 David Chalmers, The Conscious Mind, 1996, p. 5
12 Colin McGinn, "Can We Solve te Mind-Body Problem" in Ned Block, Owen Flanagan and Guven Guzeldere, eds., The Nature of Consciousness Cambridge, Mass.: MIT Press, 1997, p. 529
13 Michael Tye, Consciousness Revisited: Materialism without Phenomenal Concepts. Massachusetts: The MIT Press, 2009, xi
14 Fodor Jerry A., "Can there be a science of mind? Times Literary Supplement, No. 4657, July 3, 1992, p. 5
15 Thomas Nagel, "The Problem of Consciousness" in David Dennett, Consciousness Explained, London: Allen Lane, 1991, p.372
16 Searle John, "The Problem of Consciousness". In Antti Revonsuo and Marti Kamppinen (eds.) Consciousness in Philosophy and Cognitive Neuroscience. New Jersey: Lawrence Erlbaum Associates Inc., 1994.
17 Joseph Levine, Purple Haze: The Puzzle of Consciousness, p. 7
18 Joseph Levine, Purple Haze: The Puzzle of Consciousness, p. 7
19 Nicholas Bunnin and E. P. Tsui-james, Blackwell Companion to Metaphysics_(Oxford: Blackwell Publishers Ltd., 1996), p. 64
20 John L. Tienson, 1989, "A Conception of Metaphysics". American Philosophical Quarterly, Volume 26, Number 1, p. 63
21 This is reminiscent of the Kantian distinction between the noumena and the phenomena worlds. It is important to note that 'Kant's conception of things in themselves as noumena, contrasted with empirical objects as phenomena, has been controversial from the beginning.' Since this distinction and the controversies around it are not our immediate objects of concern, we shall not discuss them. For a comprehensive interpretation and defense of the distinction, see Robert Merrihew Adams, 1997. "Things in Themselves", Philosophy and Phenomenological Research, Vol. 57, No. 4, pp. 801825.
22 John L. Tienson, p. 63
23 See Ward E. Jones, 2011. "Being Moved by a Way the World is Not", Synthese, 178, pp. 131-141. Here, Jones examined Bas van Fraassen's view expressed in The Empirical Stance that the change of view involved in scientific revolutions as being, at least in part, emotional. Jones understood van Fraaseen to mean that there is a description of the world which is entirely owed to the emotional approval of someone, e.g., a scientist, and that this, as it may turn out, may not be the way the world is. This suggests that there is a way the world is, different from the way it is described to be.
24 This understanding of the qualitative properties of mental states is due to Stephens G. Lynn, in his analysis of CS. Peirce's account of the qualitative properties of mental states as feeling as it is in itself. See Stephens G. Lynn, 1985. "Noumenal Qualia: CS. Peirce on Our Epistemic Access to Feelings", Transactions of the Charles S. Peirce Society, Vol. 21, No. 1, pp 95-108
Adams Robert Merrihew, (1997) Things in Themselves, Philosophy and Phenomenological Research, 57 (4) pp 801-825
Bunnin Nicholas and Tsui-james E. P., (1996) Blackwell Companion to Metaphy sicsx Oxford: Blackwell Publishers Ltd.
Chalmers David J., (1996) The Conscious Mind: In Search of a Fundamental Theory. Oxford: Oxford University Press
Coates Paul and Coleman Sam, (2009) Science Daily, Researchers Explore What Contemporary Science Cannot Explain, http://www.sciencedailv.com/releases/2009/01/090123075632.htm (April 7, 2009)
Coghill Robert C, McHaffie John G., and Yen Ye-Fen, (2003) Neural Correlates of Interindividual Differences, in The Subjective Experience of Pain, Proceedings of the National Academy of Sciences (PNAS), 100 (14).
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Fasiku Gbenga and Oyelakin R.T
Department of Philosophy,
Obafemi Awolowo University, Ile-Ife, Nigeria