One of the reasons for the current explosion of interest in the study of consciousness has been the development of new technologies for the study of the brain. This has given rise to a widespread optimism within the neuroscience community that a theory of consciousness could be just around the corner.
However many commentators have pointed out that although there has been undoubted progress in the study of the neural correlates of consciousness, there is still an "explanatory gap." What sort of theory would it take to bridge the gap between brain processes and phenomenal experience?
Philosopher David Chalmers gave eloquent expression to this at the first Tucson conference, when he drew a distinction between the "easy problems" (cognitive functions like discrimination and the focus of attention) and the "hard problem" (why should any of this be accompanied by phenomenal experience?).
The Journal of Consciousness Studies is publishing a three-part special issue in which authors are invited to address this "hard problem". The first two issues are now available, and contain the following articles:
Additional Hard Problem articles appear in Issue 3, No.3, Issue 3, No.4, Issue 3, No.5/6
Chalmers' response appears in Issue 4, No.1
Full text for the Chalmers keynote paper is available and, for North American browsers, we also include a link to the US connection.
But it's a long paper, and who wants to sit in front of a computer all day anyway? So we have printed an extra 1000 copies of these two issues which we are making available at the special price of $US 8.50 (UK 5 pounds) each. The price includes accelerated delivery for US, UK and Europe, surface elsewhere (airmail extra $2.50 (UKP 1.50).
Or take out a subscription for the current year (Vol.4, 1997) and we will send you the original special issue (containing David Chalmers' keynote article and six commentaries) free of charge.
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JCS, 2 (3), 1995, pp. 200-19
David J. Chalmers,
Department of Philosophy,
University of California
Santa Cruz, CA 95064,
Consciousness poses the most baffling problems in the science of the mind. There is nothing that we know more intimately than conscious experience, but there is nothing that is harder to explain. All sorts of mental phenomena have yielded to scientific investigation in recent years, but consciousness has stubbornly resisted. Many have tried to explain it, but the explanations always seem to fall short of the target. Some have been led to suppose that the problem is intractable, and that no good explanation can be given.
To make progress on the problem of consciousness, we have to confront it directly. In this paper, I first isolate the truly hard part of the problem, separating it from more tractable parts and giving an account of why it is so difficult to explain. I critique some recent work that uses reductive methods to address consciousness, and argue that these methods inevitably fail to come to grips with the hardest part of the problem. Once this failure is recognized, the door to further progress is opened. In the second half of the paper, I argue that if we move to a new kind of nonreductive explanation, a naturalistic account of consciousness can be given. I put forward my own candidate for such an account: a nonreductive theory based on principles of structural coherence and organizational invariance and a double-aspect view of information.
The full text is available.
JCS, 2 (3), 1995, pp. 241-55
Thomas W. Clark,
7 Partridge Ave.,
Somerville, MA 02143,
This paper critiques the view that consciousness is likely something extra which accompanies or is produced by neural states, something beyond the functional cognitive processes realized in the brain. Such a view creates the `explanatory gap' between function and phenomenology which many suppose cannot be filled by functionalist theories of mind. Given methodological considerations of simplicity, ontological parsimony, and theoretical conservatism, an alternative hypothesis is recommended, that subjective qualitative experience is identical to certain information-bearing, behaviour-controlling functions, not something which emerges from them. This hypothesis explains the isomorphism between the structure of experience and neural organization, while providing a naturalistic account of qualia as relational properties of informational states, not a separate ontology of phenomenal essences. On this functionalist view, the hard, empirical problem of consciousness is to discover precisely which neural functions constitute subjective experience.
JCS, 2 (3), 1995, pp. 231-40
University of Southampton,
Faculty of Mathematical Studies,
Southampton SO17 1BJ,
The dominance in normal awareness of visual percepts, which are linked to space, obscures the fact that most thoughts are non-spatial. It is argued that the mind is intrinsically non-spatial, though in perception can become compresent with spatial things derived from outside the mind. The assumption that the brain is entirely spatial is also challenged, on the grounds that there is a perfectly good place for the non-spatial in physics. A quantum logic approach to physics, which takes non-locality as its starting point, offers a non-reductive way of reconciling the experience of mind with the world description of physics. For further progress it is necessary to place mind first as the key aspect of the universe.
JCS, 2 (3), 1995, pp. 266-71
Department of Philosophy,
University of Durham,
This paper challenges David Chalmers' proposed division of the problems of consciousness into the `easy' ones and the `hard' one, the former allegedly being susceptible to explanation in terms of computational or neural mechanisms and the latter supposedly turning on the fact that experiential `qualia' resist any sort of functional definition. Such a division, it is argued, rests upon a misrepresention of the nature of human cognition and experience and their intimate interrelationship, thereby neglecting a vitally important insight of Kant. From a Kantian perspective, our capacity for conceptual thought is so inextricably bound up with our capacity for phenomenal consciousness that it is an illusion to imagine that there are any `easy' problems of consciousness, resolvable within the computational or neural paradigms.
JCS, 2 (3), 1995, pp. 220-30
Dept. of Philosophy,
P.O. Box 270,
Consciousness lacks extension and other spatial properties. But how can this be, if it arises from matter in space? The paper argues that this conundrum can only be solved by recognizing that our current conception of space is fundamentally inadequate. However, no other conception is available to us.
JCS, 2 (3), 1995, pp. 272-88
University of Toronto,
1265 Military Trail,
Ontario M1C 1A4,
The generation problem is to explain how material configurations or processes can produce conscious experience. David Chalmers urges that this is what makes the problem of consciousness really difficult. He proposes to side-step the generation problem by proposing that consciousness is an absolutely fundamental feature of the world. I am inclined to agree that the generation problem is real and believe that taking consciousness to be fundamental is promising. But I take issue with Chalmers about what it is to be a fundamental feature of the world. In fact, I argue that taking the idea seriously ought to lead to some form of panpsychism. Powerful objections have been advanced against panpsychism, but I attempt to outline a form of the doctrine which can evade them. In the end, I suspect that we will face a choice between panpsychism and rethinking the legitimacy of the generation problem itself.
JCS, 2 (3), 1995, pp. 255-65
Department of Psychology,
Goldsmiths, University of London,
London, SE14 6NW,
Within psychology and the brain sciences, the study of consciousness and its relation to human information processing is once more a focus for productive research. However, some ancient puzzles about the nature of consciousness appear to be resistant to current empirical investigations, suggesting the need for a fundamentally different approach. In Velmans (1991a; b; 1993a) I have argued that functional (information processing) accounts of the mind do not `contain' consciousness within their workings. Investigations of information processing are not investigations of consciousness as such. Given this, first-person investigations of experience need to be related nonreductively to third-person investigations of processing. For example, conscious contents may be related to neural/physical representations via a dual-aspect theory of information. Chalmers (1995) arrives at similar conclusions. But there are also theoretical differences. Unlike Chalmers I argue for the use of neutral information processing language for functional accounts rather than the term `awareness'. I do not agree that functional equivalence cannot be extricated from phenomenal equivalence, and suggest a hypothetical experiment for doing so - using a cortical implant for blindsight. I argue that not all information has phenomenal accompaniments, and introduce a different form of dual-aspect theory involving `psychological complementarity'. I also suggest that the hard problem posed by `qualia' has its origin in a misdescription of everyday experience implicit in dualism.
JCS, 3 (1), 1996, pp.4-6
Daniel C. Dennett
Center for Cognitive Studies,
The strategy of divide and conquer is usually an excellent one, but it all depends on how you do the carving. Chalmer's (1995) attempt to sort the `easy' problems of consciousness from the `really hard' problem is not, I think, a useful contribution to research, but a major misdirector of attention, an illusion-generator. How could this be? Let me describe two somewhat similar strategic proposals, and compare them to Chalmers' recommendation.
JCS, 3 (1), 1996, pp.7-13
Valerie Gray Hardcastle
Department of Philosophy,
Virginia Polytechnic Institute and State University,
In this essay, I hope to make clearer what the points of division between the materialists and the sceptics are. I argue that the rifts are quite deep and turn on basic differences in understanding the scientific enterprise. In section I, I outline the disagreements between David Chalmers and me, arguing that consciousness is not a brute fact about the world. In section II, I point out the fundamental difference between the materialists and the sceptics, suggesting that this difference is not something that further discussion or argumentation can overcome. In the final section, I outline one view of scientific explanation and conclude that the source of conflict really turns on a difference in the rules each side has adopted in playing the game.
JCS, 3 (1), 1996, pp.14-25
William S. Robinson
Department of Philosophy,
Iowa State University,
This paper offers an account of why the Hard Problem cannot be solved within our present conceptual framework. The reason is that some property of each conscious experience lacks structure, while explanations of the kind that would overcome the Hard Problem require structure in the occurrences that are to be explained. This account is apt to seem incorrect for reasons that trace to relational theories of consciousness. I thus review a highly developed representative version of relational theory (namely, David Rosenthal's, 1986; 1990) and explain why I do not find it acceptable. This rejection requires a nonrelational alternative, which I describe and defend against a certain further objection. Finally, I discuss implications of the foregoing for the views of McGinn (1991) and Chalmers (1995).
JCS, 3 (1), 1996, pp.26-32
Div. of Philosophy,
Virginia Commonwealth University,
915 West Franklin Street,
David Chalmers (1995) calls the problem of explaining why physical processes give rise to conscious phenomenal experience the `hard problem' of consciousness. He argues convincingly that no reductive account of consciousness can solve it and offers instead a non-reductive account which takes consciousness as fundamental. This paper argues that a theory of the sort Chalmers proposes cannot hope to solve the hard problem of consciousness precisely because it takes the relation between physical processes and consciousness as fundamental rather than explicable. The hard problem of consciousness is, for reasons Chalmers himself gives, insoluble. Its insolubility does not, however, impugn the naturalistic respectability of consciousness.
JCS, 3 (1), 1996, pp.33-35
Department of Physiology,
University of California, San Francisco,
Solutions to the `hard problem' of consciousness must accept conscious experience as a fundamental non-reducible phenomenon in nature, as Chalmers suggests. Chalmers proposes candidates for an acceptable theory, but I find basic flaws in these. Our own experimental investigations of brain processes causally involved in the development of conscious experience appear to meet Chalmers' requirement. Even more directly, I had previously proposed a hypothetical `conscious mental field' as an emergent property of appropriate neural activities, with the attributes of integrated subjective experience and a causal ability to modulate some neural processes. This theory meets all the requirements imposed by the `hard problem' and, significantly, it is experimentally testable.
JCS, 3 (1), 1996, pp.36-53
Departments of Anesthesiology and Psychology,
University of Arizona,
University of Oxford,
24–29 St. Giles,
Oxford OX1 3LB,
What is consciousness? Some philosophers have contended that `qualia', or an experiential medium from which consciousness is derived, exists as a fundamental component of reality. Whitehead, for example, described the universe as being comprised of `occasions of experience'. To examine this possibility scientifically, the very nature of physical reality must be re-examined. We must come to terms with the physics of space–time — as is described by Einstein's general theory of relativity — and its relation to the fundamental theory of matter — as described by quantum theory. This leads us to employ a new physics of objective reduction: OR which appeals to a form of `quantum gravity' to provide a useful description of fundamental processes at the quantum/classical borderline (Penrose, 1994; 1996). Within the OR scheme, we consider that consciousness occurs if an appropriately organized system is able to develop and maintain quantum coherent superposition until a specific `objective' criterion (a threshold related to quantum gravity) is reached; the coherent system then self-reduces (objective reduction: OR). We contend that this type of objective self-collapse introduces non-computability, an essential feature of consciousness. OR is taken as an instantaneous event — the climax of a self-organizing process in fundamental space–time — and a candidate for a conscious Whitehead-like `occasion' of experience. How could an OR process occur in the brain, be coupled to neural activities, and account for other features of consciousness? We nominate an OR process with the requisite characteristics to be occurring in cytoskeletal microtubules within the brain's neurons (Penrose and Hameroff, 1995; Hameroff and Penrose, 1995; 1996).
JCS, 3 (1), 1996, pp.54-68
Dept. of Philosophy,
Virginia Commonwealth University,
It stands to reason that full understanding of what is involved in the `hard problem' will emerge only on the basis of systematic scientific investigation of the subjective phenomena of consciousness, as well as the objective phenomena of matter. Yet the idea of such a systematic scientific investigation of the subjective phenomena of consciousness has largely been absent from discussions of the `hard problem'. This is due, apparently, both to philo- sophical objections to the possibility of such a science of consciousness, and to the absence of appropriate subjective investigative methodologies. The present paper argues (1) that cognitive-developmental research on the development of the mental/physical distinction in young children undercuts standard philosophical objections to the possibility of an appropriate scientific study of the phenomena of consciousness, (2) that methodologies for exploring the contents and dynamics of consciousness akin to those developed in Eastern cultures could play a significant role in the development of such a science of consciousness, and (3) that the experience of `pure consciousness' often reported in association with these methodologies suggests reformulation of our ordinary ideas about the relationships between consciousness, qualia, and the objective world that may prove particularly useful for resolution of the `hard problem'.
JCS, 3 (1), 1996, pp.69-75
Supreme Court of New South Wales,
David Chalmers distinguishes the hard problem of consciousness — why should a physical system give rise to conscious experiences at all — with what he calls the easy problems, the explanation of how cognitive systems, including human brains, perform various cognitive functions. He argues that the easy problems are easy because the performance of any function can be explained by specifying a mechanism that performs the function. This article argues that conscious experiences have a role in the performance by human beings of some cognitive functions, that can't be realised by mechanisms of the kind studied by the objective sciences; and that accordingly some of Chalmers' easy problems will not be fully solved unless and until the hard problem is solved.
JCS, 3 (1), 1996, pp.76-88
Dept. of Philosophy,
If experience cannot be explained reductively, then we must embrace a revised understanding of nature to explain it. What kind of revision is required? A minimal revision would merely append a theory of experience onto an otherwise adequate theory of cognition, without going far beyond considerations peculiar to the study of the mind. I argue that we will need a more expansive revision, requiring us to rethink the natural order quite generally. If this is right, we will view the mind as a special context in which something new to our understanding of the world, and much more general, is being manifested.
Journal of Consciousness Studies