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Mainstream 8Summaries and reviews of papers, articles and books relative to mainstream theories of consciousness 1.) Ghosts in the Machine - Steven Pinker - Pinker surprises by adopting the new mysterian view that we are incapable of understanding consciousness, despite insisting that it does not depend on anything outside classical physics. Assertions relative to what Penrose said are incorrect. 2.) Roger Penrose's Gravitronic Brains - Hans Moravec - Unconvincing critique of Penrose's interpretation of the Godel theorem 3.) Are We Spiritual Machines & The Singularity is Near - Ray Kurzweil - Kurzweil is put forward as a champion against Penrose/Hameroff theories 4.) Free Will is Un-Natural - John Bargh - Mostly ignores consciousness in discussing freewill and tends towards revival of behaviourism. 5.) The Continuity of Mind - Spivey, M. - Epiphenomenal view of consciousness expounded here and derived from Dennett appears to be refuted by modern experiments. 6.) Making up the Mind - Chris Frith - Freewill is both adaptive and an illusion, but may fail in justifying the illusionary aspect. 7.) The Anatomy of Thought - Ian Glynn - Criticism of Dennett from a mainstream researcher 1.) Ghosts in the Machine Steven Pinker Cosmos - Feb/March 2007 Pinker starts his article by sketching his definition of consciousness. Consciousness is life itself, and the conviction that other people suffer or flourish is the essence of empathy and the foundation of morality. Pinker discounts the once fashionable notion that consciousness depends on language, pointing to both infants and brain damaged patients, who have lost the power of speech or of comprehension of speech but appear to remain conscious. Consciousness is also said to be different from self-awareness, in that one can lose oneself in music or other sensory pleasures. He might also have said that in many examples of altered states of consciousness the self is felt to have disappeared, although there is still something that observes. Pinker agrees with Chalmers that the hard problem is to determine why it feels like something to have conscious processes in one’s brain, and why we have qualia, such as the experience of the colour green. The hard problem is to explain how subjective experience arises from the computational processing of the brain. Pinker stresses the distinction between conscious and unconscious processes He is sympathetic to Bernard Baar’s idea of a global workspace in which the focus of attention and the working memory represent an ‘executive summary’ selected from an otherwise overwhelming flood of data into the brain. Unusually for recent commentators, Pinker sees consciousness as depending on ‘certain frequencies of oscillation’ in the EEGs between the cortex and the thalamus, and although not mentioned as such, this would usually refer to the 40Hz or gamma synchrony. This is suggested to solve the binding problem, by tying together activity in different parts of the cortex. Pinker takes the interesting example of studies of two eyes competing in binocular rivalry, in which neurons related to the ‘winning’ eye oscillate in synchrony, while those related to the ‘losing’ eye fall out of synchrony. Elsewhere, Pinker refers favourably to the consciousness work of Crick and Koch, seemingly unaware that it was they who first widely publicised the gamma synchrony, but then subsequently encouraged the mainstream to downplay the idea, once it was discovered that the synchrony related to activity in the dendrites rather than action potentials. As a result, some modern discussions of consciousness now ignore the gamma synchrony altogether. Pinker admits that features such as the gamma synchrony are only correlates of consciousness, and as such they are only part of the ‘easy problems’ of consciousness, and still do not tell us how or why subjective consciousness is produced. As in much consciousness writing, a good start is followed by a tailing off in the quality of discussion. Some of the latter part of the article might be felt to be wasted in descriptions of psychological experiments that show the brain produce illusions as to what it is perceiving and as to the freedom of its actions. There seem to be two points to make about these experiments. In the first place, they produce highly contrived and artificial situations that are most unlikely to have arisen in the hunter-gathering life that we evolved to cope with, and where we would have been unlikely to have survived as a species, if we were really that prone to illusions. The other point is that even if we are so illusion ridden, we still have to be conscious to experience the illusions, so this doesn’t get us any nearer to a discovering the basis of consciousness. In the end, Pinker has little joy in trying to wrap up the final part of his article. Dennett’s position is too much for him. Reducing consciousness to, or identifying it with information processing and nothing more, seems to him to amount to the denial of the undeniable fact that we experience consciousness. His reference to quantum consciousness is both brief and incorrect. He appears to suggest that it was Roger Penrose who advanced the opinion that because quantum theory was weird, and consciousness was weird, the two might be connected. In fact, this was a criticism or rather mockery concocted by opponents of quantum consciousness, which is here quite wrongly passed off as if they were Penrose’s core argument. The comment here probably arises from Pinker’s ignorance of quantum consciousness theories, but it is nevertheless the sort of sleight of hand that is all too common in consciousness studies. Pinker, perhaps surprises by not going for the mainstream take on consciousness, which is that continuing research will disclose a basis for consciousness broadly supportive of functionalism or identity theory. Instead, he plumps for the ‘new mysterian’ approach, although he doesn’t give it that name. This view has been championed by Colin McGinn of the University of Miami, who argues that it is beyond the ability of brains evolved from those of apes, and honed to hunter-gathering, to grasp the nature of subjective consciousness. There is a certain intuitive attraction to this view, in that we sense something ineffable, when we try to relate consciousness to the physical world. However, the new mysterian view looks to be much more compatible with either a dualist/spirit stuff or a quantum view of consciousness, than it is with Pinker’s mainstream materialism. It is quite plausible that ape brains might not grasp the nature of a spirit, and it is certainly true that they struggle with the acausal randomness and non-locality of quantum theory. What is implausible, given the impressive structure of scientific knowledge built up by the ape brains over the last 400 years, is that these brains cannot grasp the nature of a consciousness that can be described by classical physics and which depends on the conventional brain mechanics of electrical potentials and amino-acids. 2.) PENROSE'S GRAVITONIC BRAINS Hans Moravec Robotics Institute Carnegie Institute University Pittsburgh, PA 15213 Albert Imperator (AI) (really Penrose in this context), the inventor of an advanced robot and the robot itself discuss an algorithm by which the society of advanced robots, known as SMIRC, certifies mathematical proofs. The Gödel sentence for this algorithm is called Omega(Q*), and it is constructed from the society’s algorithm. It means that SMIRC’s algorithm certifies a particular statement. The robot asserts that SMIRC never makes mistakes. However, if SMIRC certifies the Gödel sentence, it makes the Gödel sentence false, thus creating a paradox. Humans can use their understanding to see that the Gödel sentence is true, but neither humans nor SMIRC can certify it as proved, without creating a paradox. Hans Moravec of the Robotics Institute at Carnegie Mellon University claims that incongruities in Penrose’s argument are expressed in a subsequent spoof discussion between Penrose and the robot. Following on Penrose’s claim that only human mathematical understanding and not SMIRC certification can cope with the Gödel sentence, Moravec kicks off his dialogue with a classic error that dogs much discussion regarding the ability of consciousness to arise from classical computation. This is the notion that opponents of classical computer based consciousness are proposing some form of competition between human brains and computers. The opponents are supposed to be claiming that human brains are superior in a direct one-to-one comparison, whereas what they are actually saying is that while computers are superior in many respects, and will become more so in the future, human brains are different, in that they give rise to consciousness and certain types of understanding. Moravec’s next step is to compare, what is here claimed to be Penrose’s defence of, as it is quaintly put, ‘a viscerally attractive position’ with Wilberforce’s defence of, what we now call Creationism, against Darwin. The strange thing about this is that it does not occur to Moravec that the comparison would fit a lot better, if he was himself in the role of Wilberforce, and it was Penrose who was in the role of Darwin. It is Moravec that is defending the established orthodoxy, whilst it is Penrose that is proposing a controversial new theory. Nor is it a valid argument, to try and make a distinction between religious and scientific orthodoxy, since Kelvin, one of the leading physicists of his day, opposed Darwin, on what were according to the knowledge of that time entirely reasonable grounds. Perhaps aware that the Wilberforce argument is not entirely convincing, Moravec moves on to the ‘science by popular vote stratagem’. The logic and neurobiological communities rejected Penrose’s proposals. Well, science depends on observation, experiment and reasoned interpretation, not on ‘Pop Idol’ type votes. The rejection by these communities sounds impressive, as if numerous mighty minds had toiled through the night preparing different reasoned refutations, but reading the reality gives more the impression of a knee jerk reaction (one for each community) from those assured of certain certainties. The logic community, closely allied to artificial intelligence, refuses to contemplate anything beyond the classical computer, which only goes to remind us that each age from ancient Greece onwards has compared the mind to the most recent technology. As for the neurobiological community, it remains stuck with the neuron as the one fundamental unit, perhaps because until a generation ago, technology prevented much observation below that level. Writing in 1995, Moravec goes on to predict how the exponential growth of computing power will lead to the displacement of human intellectual and physical labour by capable machines. Others like him in the later 1990s produced predictions of how machines would displace and even rule humans by the first few years of the 21st century. The first part of Moravec’s prediction is true. Computer power has continued to grow rapidly over the intervening 13 years. Computers are more capable, but artificial intelligence is stuck in the same rut as it was during all the latter decades of the last century. Although they would be in great demand, there is no significant signs of the type of autonomous robots that could perform household chores, or look after old people and children. Even in more strictly intellectual areas, there are few who would grant them the type of understanding needed to make policy or strategic decisions. The establishment is still bound to the primacy of the classical computer, but for those with eyes to see, it is apparent that the algorithm for common sense and meaning is lacking, at least for classical computers. It is only on page three of his ‘dialogue’ that Moravec begins to get down to serious logic chopping. In a rather crude approach, he tries to overwhelm the Penrose argument. His robot now has such a powerful brain that its programmes and Gödel sentences are too large for Penrose to read. Even in this rather slanted dialogue, Penrose is allowed to mention that according to his own theory, however large the robot programme or Gödel sentences, the human brain still has an understanding that is lacking in the robot brain. In reply, Moravec launches off into what amounts to an ungrounded speculation about the future greatness of robot brains, and in particular anticipates the modern fashion for a multiverse, in which robots are able to realise Gödel sentences that are true in some realities but not in others. The reality, or rather lack of it, of modern AI, should perhaps be seen as a bench mark for the plausibility of what Moravec’s robot tries to claim. 3.) Are We Spiritual Machines (1999) and The Singularity is Near (2005) Ray Kurzweil These books would not be interesting in respect of consciousness theory, if it were not that Susan Blackmore, who is prominent in consciousness studies, turned to Kurzweil to help refute Penrose’s quantum consciousness theory. This seems an odd choice, as Kurzweil was firstly an entrepreneur in the computer industry and later diversified into writing popular ‘futurist’ books. He was not a specialist in either physics or neuroscience. In respect of consciousness, Kurzweil’s main argument is that computer technology will progress fast enough for himself and others to download themselves into computers before the middle of the 21st century. In ‘Are We Spiritual Machines’ Kurzweil is therefore mainly concerned that Penrose’s version of quantum consciousness should not get in the way of people being downloaded into computers, rather than with entering into any deeper discussion of the nature of consciousness. His first argument is that the brain has more than enough capacity to do what it does without using quantum computing. In fact, some researchers argue that known brain capacity is not enough to resolve the perception of ambiguous objects (1.- 6.). Kurzweil does not appear to have done his homework here, confidently stating that ‘no one has suggested human capabilities that would require a capacity for quantum computing’. He goes on to give a garbled account of how the Penrose/Hameroff theory arose. He refers to it being ‘pointed out to Penrose that neurons were too big for quantum computing’, whereas this was obvious to anyone familiar with physics. Penrose in fact offered only the vaguest suggestions for possible mechanisms in his first book. Kurzweil then refers to Penrose ‘coming up with the tubule theory’ whereas this is a product of pre-existing work by Stuart Hameroff, who became Penrose’s partner in developing the Orchestrated Objective Reduction (Orch OR) theory of consciousness. However, the real point is that Penrose is talking about ‘understanding’ and by extension consciousness, as distinct from information processing. In the Penrose/Hameroff hypothesis, the quantum feature is primarily required to generate consciousness. In contrast, Kurzweil is really only discussing information processing, and gives us no clue as to what it is that makes conscious processing of information in the brain different from non-conscious processing either in or out of the brain. He does not seem to be aware of this as a problem. Kurzweil’s second book ‘The Singularity is Near’ (2005) attempts a slightly more serious discussion of Penrose, but it was first book, written in 1999, that Blackmore refers to. Kurzweil starts by quoting Koch who wrote ‘Quantum mechanics is mysterious, and consciousness is mysterious. Q.E.D. Quantum mechanics and consciousness must be related.’ The quote is an intentionally silly suggestion. Needless to say, Penrose never said or implied anything of the sort. It does little credit to the standards of discussion in consciousness studies for this sort of thing to be highlighted. Good science is not done in this way. In his own discussion, Kurzweil starts by conflating two unrelated arguments. First of all, he goes back to the argument proposed in ‘Are We Spiritual Machines’ that human capabilities do not require the brain to have the extra capacity provided by quantum computing. He says that no one has suggested such a thing, which is not in fact true, as other investigators besides Penrose have argued that there may be a capacity problem (1. – 6.). He then introduces a quote from Seth Lloyd to support his claim. As a physicist, Lloyd outlines the main real objection to quantum consciousness, which is the speed of quantum decoherence in the normal conditions of the brain. This is an important objection, but it is absolutely nothing to do with the Kurtzweil argument it is called on to support. Kurtzweil also trundles the old mantra, peppering much of consciousness studies, that there is no scientific evidence or that there is little scientific evidence for such and such. The casual reader can take this to mean that a particular proposition has been shown to be false, whereas what it usually means is that little or no research has been undertaken in the particular area, often because funding would never be forthcoming. A further disconcerting feature of both these books is that important and controversial claims often go unreferenced, in fact the first book has no references at all. Further discussion in the second book again misses the point that Penrose/Hameroff are discussing consciousness, rather than just the modelling of information processing. Again, Kurzweil far from being someone to refer to on consciousness seems to largely ignore it as a distinct feature. His main concern, as in the first book, seems to be to prevent Penrose getting in the way of his own pet project of downloading minds into computers. Finally, the author discuss Gödel’s theorem, the related work of Turing and the Church-Turing thesis. Gödel argued that propositions that could not be proved by a particular system of axioms could still be obviously true. Kurtzweil tries to turn this round by means of a strong interpretation of the Church-Turing thesis, to the effect that because the human brain comprises matter and energy, and that these are governed by the laws of physics, then any human understanding can be expressed in terms of an algorithm, which is by definition something that can be handled by a computer. This argument essentially works by assuming the thing it sets out to prove, because the Penrose proposition is that some physics, notably objective reduction of the wave function is non-computable. References:- 1.) James A. Donald – Evidence supporting information processing in animals 2.) Kanade, T. (1980) – Artificial Intelligence, 13, 279 3.) Kanade, T. (1981) – Artificial Intelligence, 17, 409 4.) Ullman, S. (1980) – Behaviour and Brain Sciences, 3, 373 5.) Gregory, R. – The Intelligent Eye – McGraw Hill 6.) Deutch, D - Proceedings of the Royal Society (London) A ) 97 4.) Free Will is Un-Natural John Bargh In: Are We Free? Psychology and Free Will Bargh admits to the existence of preferences, motivations, desires and goals as things that influence people. He asks whether actions are the result of free choices influenced by preferences etc., or whether our actions are determined by the preferences. without any coordinating element of free choice. At the start of his chapter, Bargh seems to be creating more problems than he resolves. Preferences, motivations, desires and goals are part of conscious subjective experience. If they influence actions, even without central coordination, consciousness and therefore some form of free will seems to be pulled into the fray. Of course, it could be argued that the subjective experience of the preferences is epiphenomenal, or an illusion, but this leaves open, the further question of why evolution would allow energy to be tied up in producing something useless. Bargh discusses the fact that while we view our own actions in the light of our thoughts prior to action, we view the actions of third parties and elements in the environment retrospectively. He seems to be trying to argue that because the viewing of third parties action is retrospective, the retrospective account must be more scientific, because science operates on a third party basis. However, science has no choice in most cases, and the first person experience is a brute fact, which it is part of the scientific mission to describe. An experiment by Pronin and Kugler is supposed to show that individuals attribute free will only to themselves. It may be that when asked people ascribe rational motives to third parties, but the whole experience of life says that people do in fact think that others have choice, and indeed blame them for making bad choices. Regarding third parties as not having free choice, while one has it oneself would seem to verge on autism, where others can be regarded as ‘wind-up toys’. Bargh’s view of the past or what he thinks our view of the past is, appears strange. It is claimed that once things have receded into the past, they are fixed and determined, as if nothing else could have happened. While it is true that experts, such as historians and economists, called onto explain why an event happened, can gives things a rather determinist spin, it is, nevertheless, ridiculous to suggest that people always think that past actions are determined, and that they couldn’t of caught the train, got the job etc., if their past actions had been slightly different. Bargh argues from the existence of innate conservatism in preferring things as they are, but this is different from seeing them as absolutely inevitable. Bargh also has a tendency to try and stand things on their head. Studies have shown that people feel better when they have a degree of control over their affairs rather than feeling helpless. The reasonable explanation of this is that the brain evolved to contain something that needed to be in control. Bargh, without offering any particular explanation as to why, deems the better feeling of being in control to be a ‘positive illusion’, but again why does nature expend energy on an illusion. It would seem much more economical for humans to have evolved to not be bothered about not being in control. Barghs tends to avoid the issue of consciousness in his discussion of freewill. He has a long section on how preferences are rooted in the unconscious. What he does not mention is that preferences are consciously experienced, with the implication that actions driven by preferences are also driven by the conscious will. Of course, Bargh would probably argue that the conscious experience of the preferences is epiphenomenal, but that only brings us back to the question of why evolution selected to consume energy in conscious experience. For his part, by ignoring considerations such as this, Bargh has been able to resurrect the ghost of behaviourism. He admits that Skinner was wrong in not allowing for internal cognitive mechanisms in the brain, but concludes that these mechanisms are after all driven only by the environment, so behaviourism is right in principle. What one should note here, is that Bargh and many others like him are in fact unconscious Cartesians, as is indicated by his reference to there being no need for a ‘ghost in the machine’. The assumption here is that whatever consciousness and conscious will is, it must be some sort of non-physical ghost thing, incapable of influencing the physical world. This is despite modern experiments that imply that conscious processing is energy consuming (1.Baumeister, Heatherton & Tice, 1994 2. Baumeister et al, 1998, 3. Vohs et al, 2006 4. Schmeichel, Vohs & Baumeister, 2003 5. Amir et al, 2005). References:- 1.) Baumeister, Heatherton & Tice (1994) - How and why people fail at self-regulation - Academic Press 2.) Baumeister et al (1998) - Is the active self a limited resource? - Journal of Personality and Social Psychology, 74, pp. 3.) Vohs et al (2006) - Decision fatigue exhausts self regulatory resources 4.) Schmeichel, Vohs & Baumeister (2003) - Role of the self in logical reasoning - Journal of Personality and Social Psychology, 85, pp. 33-46 5.) Amir et al (2005) - The fatigued decision maker 5.) The Continuity of Mind Michael Spivey Oxford University Press Only the final chapter is discussed here. The author himself indicates that it has little bearing on the preceding chapters. He begins on an eliminatist or at least epiphenomenal tack suggesting that consciousness might be irrelevant or non-existent. The perception-action loop in the brain, inclusive of reports of conscious experience, can according to Spivey’s theory, be explained by a deterministic attractor landscape. An experiment by (1. Kolers and Brewster, 1985) using, (for this type of psychological experiment) the characteristically trivial activity of tapping fingers to music, showed that the subjects were not consciousness of a change of phase in the music. It does not seem surprising that this monotonous activity might be done on automatic pilot, while consciousness could be engaged with something else. Nevertheless, this is sufficient evidence for the author to dismiss all subjective reports as a mere ‘curiosity’. He also quotes the rather similar Libet experiments that showed readiness potentials preceding consciousness of the desire to act. He does not, however, mention that this only involved automatic pilot type finger flexing, rather than more strategic actions, where the involvement or otherwise of consciousness might be more relevant to discussions about consciousness and freewill. In common with many who have to write about consciousness, Spivey looks to a philosopher, in this case, Daniel Dennett, for support. This introduces a certain circularity to the argument, since the type of philosopher selected can be said to have seen it as their duty to prop up the ‘Newtonian’ world view. The author quotes Dennett as talking about how self-conscious introspection can revise the memory of experiences. Spivey describes what his own consciousness is supposed to be like, which resembles what Dennett describes, saying that ‘the only time that I feel I have some sense of consciousness is when I stop what I’m thinking and self-reflect on what I was thinking a second ago, and on who or what was doing that thinking.’ He argues from this that his consciousness is filtered through memory and therefore distorted and worthless. He does not seem to notice that what he was actually conscious of at the beginning was the thinking at the moment before his pause for introspection started. He also fails to mention his experience of elements of the external world, such as the colour of the sky or the grass in the college quad, which presumably do not require introspection. Moreover, even with introspection of events filtered through memory, there is still a need to explain why we are conscious of this, whether or not these memories are accurate. It is not fully clear from the text, but what we are seeing here may be the common consciousness studies trick or error of conflating the self and consciousness, whereas the self is merely part of the contents of consciousness. Spivey himself appears to agree with this, in that when he is thinking about something external and not introspecting he is not conscious of the self. However, this is generally ignored and as above, a deconstruction of the self is assumed to have dismissed the problem of consciousness. At any rate, this is one place where mainstream philosophical rumination appears to be contradicted by modern scientific experimentation. Dennett/Spivey claim that consciousness comes to us via introspection and memory. However, experiments have shown that intense fears, for instance those associated with phobias, by-pass the cortex and the hippocampal system that handle memories, and instead go directly from the thalamus to the amygdala, the centre of fear and much other emotion. (2. LeDoux, 1996, 3. Jarrell et al 1987, 4. Bordi & LeDoux, 1994). This is a separate, quicker and evolutionarily much older route than that going from the thalamus via the sensory and associational cortex to the hippocampus. With the amygdala, there is no opportunity for either the hippocampus or the prefrontal to become involved before the feared object leaps into consciousness. The author also very briefly discusses quantum consciousness ideas. He speculates on the possible effects of the superpositions of a calcium ion near a synapse, and suggests that for this to be effective, there would have to be a non-local relationship between ions in possibly thousands of neurons. This is considered unlikely, and the idea of quantum consciousness is accordingly dismissed. What he does not mention is that the model he discusses here bears no resemblance to most proposals for quantum consciousness. However, earlier references to Penrose and Jibu incorrectly imply, for those who have not studied them, that this is in fact the type of model they are proposing. Unfortunately, this is too typical of mainstream writing on quantum consciousness, where a wild swipe says more about the writers lack of knowledge of the topic than the shortcomings of the theories. References:- 1.) Kolers, P. & Brewster, J. (1985) - Rhythms and responses 6.) Making up the Mind Chris Frith Blackwell Publishing ISBN Chris Frith starts by saying that he will show that the distinction between mental and physical is false. The distinction is claimed to be an illusion created by the brain. Everything we know comes via the brain, but there is no direct connection with the physical world of objects. The first part of the book goes over sometimes familiar ground to show that the brain works on limited and imperfect signals to create a model or picture of the world, and although it is adaptive for the brain to get it right, the picture can, nevertheless, sometimes be wrong. Frith does touch on the fact of how hard perception is for computers. The perception of the view of the garden from the house may seem to be a simple matter, but for a computer there is a considerable problem in distinguishing the brown of the tree trunk from the brown of the fence, and this problem increases if objects move around. It is not mentioned in this book, but these difficulties with computer perception have been seen as an argument for quantum computing in the brain. Frith wants to show that much of what we experience is an illusion. He draws on the rather artificial psychological experiments that show that people sometimes think they have performed actions they have or vice versa. He rather by passes the fact that outside the laboratory in the real world, it is adaptive to get these perceptions right most of the time. Instead in discussing freewill, he says that it is adaptive for a social species such as humans to punish 'freeriders' who try to benefit from being part of the group without making an adequate contribution. For this to work people have to see themselves and the 'freeriders' as agents who could have acted otherwise. There seems no reason to disagree with this, but Frith's assumption that the freewill involved is an illusion does not appear to be justified by the artificial experiments quoted. Given the weakness of the experiments, the illusion proposition could be argued to lie on the wrong side of Occam's razor by loading in a new hypothesis over and above what we already know. 7.) An Anatomy of Thought Ian Glynn Weidenfled & Nicolson ISBN This review deals only with chapter 23 of this book, being the chapter that discusses consciousness and qualia. For someone who appears to be fairly mainstream in other respects, Glynn is unusually critical of Dennett and other mainstream ideas about consciousness. Glynn starts almost immediately in this chapter by discussing qualia, the 'raw' or subjective experience of the world, taking as examples such instances as the smell of coffee, the sound of an oboe or the blue of a Mediterranean sky. He stresses that we can only know what the experience of these things is like by actually having these experiences. Science can tell us what in the external world is causing us to have these experiences, and also what effect the experience is likely to have on our behaviour, but it cannot tell us what the experience is like. Glynn reminds us that much of human activity is devoted to obtaining pleasurable qualia or avoiding unpleasant qualia. Perceptions and sensations, such as the example given above, are the most obvious examples of qualia, but beliefs, desires, hopes and fears also count as qualia, because it feels like something to have a belief or a fear. Glynn contrasts the obviousness of the existence of qualia with the dismissive attitude of eliminative materialists, of which Daniel Dennett is perhaps the best known. In Glynn's view, an important aspect of of Dennett's argument against qualia is that there is no way of knowing whether one's subjective experience of red is the same as someone else's, and also whether a change in my subjective experience of, for instance, the taste of a particular brand of coffee over a period of time, represents a change in the coffee, or a change in my appreciation of it. Dennett has a lengthy rumination on how this is only a private or 'idiosyncratic complex of dispositions'. Glynn agrees that this may be so, but points out that it still does not explain why we have a subjective experience of the dispositions, private, idiosyncratic or otherwise. Dennett, in fact, is less impressive when present like this in short excerpts. In full flight, a combination of eloquent writing and subtle bullying of the reader for clinging to obsolete ideas, tends to mask the fact that he may have diverted away from the real question of subjectivity. Glynn remarks that Dennett does in places seem to be aware of this criticism, but tries to quash it by saying that if nothing follows from the 'presumed knowledge' of subjective experience, what is the point of asserting that one has it. This remark conflates two questionable approaches. First the assumption that consciousness can have no influence, which runs into problems with evolutionary theory, and second the familiar bullying of the reader for having a silly idea. Glynn is also astute in pointing out the weakness in the 'consciousness as an emergent property' explanation, as advanced by John Searle and others. Searle's example is that liquidity is an emergent property of water at ambient temperatures. It is emergent, because liquidity is not inherent to the constituent hydrogen and oxygen atoms, but emerges when they are arranged in water molecules at a suitable temperature. Glynn is prepared to accept that consciousness is an emergent property of brains. However, he argues that this is a non-explanation. Science has explained the forces that allow a certain arrangement of of hydrogen and oxygen atoms to produce liquidity, but it has not explained why a particular arrangement of biological tissues in the brain produces consciousness. span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; }span.jajahWrapper { font-size:1em; color:#B11196; text-decoration:underline; } a.jajahLink { color:#000000; text-decoration:none; } span.jajahInLink:hover { background-color:#B11196; } |
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