Unraveling the Mystery of consciousness: a defence of physicalism

Does anyone have any comments on this essay? (I hope it went through ok; it didn't copy perfectly but it looks mostly readable)

It's for a school essay I have to do.
ta
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[CENTER]Unravelling the Mystery of Consciousness: a Defence of Physicalism
Gregory Fenn[/CENTER]


Abstract: In this essay I examine the mind-body problem, starting with Rene Descartes, and the arguments from consciousness to dualism, especially that of David Chalmers. I then examine the attempts to disprove such arguments and provide physicalist accounts of consciousness with special focus on the work of Daniel Dennett. I develop a few ideas of my idea to provide support for a current or potential physicalist account of consciousness. I also refer to other difficulties such as the 'unity' of consciousness. I conclude that the approach taken in the reasoning of those who argue to dualism from consciousness is flawed in its reliance on intuition.




"Consciousness is at once the most familiar thing in the world and the most mysterious." (Chalmers, 1996, page 3)
Is it? Well let's see.


1) Introducing the Mind-Body problem: When philosophers talk about consciousness, in the context of philosophy of mind at least, what we mean is our subjective, qualitative, experience of the world: phenomenal qualities (called 'qualia'). Conscious experience feels like something, to use a phrase coined by Thomas Nagel (1974). For example we have a particular feeling of what it is like to see red, or hear a Gregorian chant, or burn our hand on a hot oven: these experiences have a particular qualia associated with them. This is not to be conflated with our psychological awareness or stimuli-response mechanisms e.g. our memory that red can symbolise danger or love in certain contexts, or our solemn behaviour in respect to a Gregorian chant, or our avoidance behaviour in respect to very hot objects.
The mind-body problem essentially asks: why should our bodily behaviour, our psychological awareness or even judgements about the world, be accompanied by consciousness at all? Surely a human could function perfectly well without experiencing what it is like to do so. For example: a human could, it seems, accidental put his hand on a hot oven, the receptors in her hand send messages to the brain to quickly remove the hand and do so without even personally experiencing pain, she need not know what it is like to feel pain as long as she can remove her hand efficiently.
Another way of understanding the mind-body problem is to ask: how can physical processes, such as in the brain, cause consciousness (in the qualia sense)? When I visualise a cow, for example, my conscious experience of what it is like to visualise a cow is very different to the physical chemicals running through my head.
The 17th Century philosopher Rene Descartes ('cogito ego sum': I think, therefore I am), in his Meditations, completely separated the non-extended 'thinking thing' from the extended material body thus developing a form of substance dualism. Descartes argued that we can think of ourselves as thinking things without bodies but not bodies without thoughts thus the two are distinct items with the thinking part being non-physical and, in principle, separable from the body (immortality of the mind or soul).
"My essence consists solely in the fact that I am a thinking thing. It is true that I may have a body that is very closely joined to me. But nevertheless, on the one hand, I have a clear and distinct idea of myself in so far as I am a simple non-extended thinking thing; and on the other hand I have a distinct idea of my body in so far as this is simply an extended non-thinking thing. Accordingly, it is certain that I am really distinct from my body and can exist without it." (Meditations 6, 54)
Few modern philosophers accept this substance dualism nowadays. The focus of this essay will be a critique of the 20th Century property dualism and a defence of physicalism1 (and so property monism). However I will briefly state the problems with Descartes theory. Firstly the fact that we think of ourselves in two distinct ways (mental and bodily) in no way shows that they actually are distinct. David Papineau (2002) gives the following example: we can have totally distinct ideas of Tully and Cicero whereas in fact they refer to the same person. Secondly it is not clear how a non-physical item (the mind) can interact with the physical (the brain). Descartes suggested that they interact via the pineal gland and that 'animal spirits' acted through the nerves to control the body. Not only is there no empirical evidence of these spirits, the coherence of the theory is easily challenged. If one substance is spiritual and not physical, the mind or these animal spirits, with no mass or charge then how can it have any causal influence on physical items with mass and charge? Or visa versa? If a spirit flew into my head, absolutely nothing of it can logically contact my physical brain to control my body. Neither would a spirit feel anything if I threw a rock at it. However dualism did not end there...


2) 20th Century Property dualism
A famous argument against physicalism (the view that in the world there is only physical stuff and physical facts: the whole world can be be reducibly explained in terms of function and structure)from the nature of consciousness was coined by Frank Jackson (1982). He coined the 'Mary and the black room' thought experiment which was meant to demonstrate that our conscious experiences are, or derive from, non-physical facts or properties: further facts. For this essay I shall rather focus on the arguments found in David Chalmers' 'The Conscious Mind: in search of a fundamental theory' (1996) which presents a more thorough and developed argument for property dualism.2
Chalmers' begins by insisting that standard, classic 20th Century philosophical investigations into consciousness which attempt to defend materialism "do not take consciousness seriously". For example they might only explain human behaviour and fallaciously conflate consciousness into that. Or they might argue that consciousness is a biological illusion (eliminativism) to which he has "little idea what this could even mean." Chalmers argues that consciousness is at the foundation and centre of our entire epistemological world-view which is why it can neither be denied nor empirically observed.
He then formally distinguishes between phenomenal and psychological conceptions of the mind. A psychological concept is the behaviour of the brain and body, or the biological information and influence, e.g. memory, sensory reception and response or awareness. In contrast, phenomenal concepts consist of these qualia: what is it like to experience this or that, e.g. pain sensations or visual experiences of the colour red.
Chalmers' later goes on to argue that our consciousness does not derive from just the physical properties in the world. To illustrate this, he proposes five arguments but I will focus on the first and fourth because they are the most interesting (though I will note any other relevant arguments elsewhere where needed).
The logical possibility of zombies:
"The most obvious way to investigate the logical supervenience of consciousness is to consider the logical possibility of a zombie: someone or something physically identical to me (or any other conscious being), but lacking conscious experience altogether. At the global level, we can consider the logical possibility [via the principle that conceivability is a rough guide to logical cohesion]3 of a zombie world: physically identical to ours but in which there are no conscious experience s at all: everyone is a zombie...... What is going on in my zombie twin? He will certainly be identical to me functionally: he will be processing the same sort of information ... with indistinguishable behaviour [from Chalmers'] resulting. He will too be psychologically identical to me [i.e. memory, perception awareness, personality etc] ... He will even be "conscious" in the functional sense of the term ... It is just that none of this functioning will be accompanied by any real conscious experiences. There will be no phenomenal feel. There is nothing it is like to be a zombie. ...... While this is probably empirically [or naturally] impossible, it certainly seems that a coherent situation is described; I can discern no contradiction in the description. ...... [T]he only route available to an opponent here is to claim that in describing the zombie world, we are misapplying the concepts, and that in fact there is a conceptual contradiction lurking in the description." (Chalmers, 1996, Pages 94-99)
I will later attempt to do just that: explain the conceptual contradiction lurking in the description used in Chalmers' argument. But for now, note that while Chalmers does argue that consciousness is not logically supervenient on the physical; he does accept that it is naturally supervenient on the physical; this means that in our world, consciousness does seem to arise from organisms with a certain construction like us (and most animals probably). What Chalmers is suggesting is that our world contains non-physical phenomenal properties. He suggests that these might be expressed in psycho-physical laws which ensure that certain constructions lead to consciousness4; or alternately that the intrinsic nature of substances (if there is any) may be phenomenology (this view is called 'panpsychicism' which is technically a form of monism though not a physical or material monism). Note that this form of dualism does not imply any form of 'soul' or definite, discrete personal identity.5
Jackson's knowledge argument:
"The most vivid argument against the logical supervenience of consciousness is suggested by Jackson (1982), following related arguments by Nagel (1974) and others. Imagine we live in a world of completed neuroscience, where we know everything there is to know about the physical processes within our brain responsible for our behaviour. Mary has been brought up in a black and white room and has never seen any colors except black and white. She is nevertheless one of the world's leading neuroscientists, specialising in the neurophysiology of color vision. She knows everything there is to know [i.e. All the physical facts] about the neural processes involved in visual information processing, about the physics of optical processes, and about the physical make-up of objects in the environment. But she does not know what it is like to see red [my underlining]. No amount of reasoning from the physical facts alone will give her this knowledge. [Further discussions often follow like this: if Mary was let out of her black and white room and shown a red apple, this knowledge of what it is like to have a red visual conscious experience is a further fact, a fact that does not derive from the physical facts. This is clear since she would not have had such knowledge before when she was just a neuroscientist - who knew all the physical facts about colour and optical reception - in a black and white world]. ...... A related way to make this point is to consider systems quite different to ourselves, such as bats ... From the physical facts about a bat, we can ascertain all the facts about a bat, except [my italics] the facts about its conscious experiences. Knowing all the physical facts, we still do not know what it is like to be a bat. [Nagel (1974) focuses on this sort of issue]" (Chalmers, 1996, Page 103)


3) What is wrong with Chalmers' argument?: One of the most interesting challenges to arguments such as Chalmers' is the paradox of phenomenal judgements. I will briefly explain this and his response and then I will reveal my scepticism of his response to the paradox. This will be followed by some common arguments for materialism and how Chalmers has responded to them. Following this I feel that I will be able to isolate to critical point that needs to be addressed thus leading to my defence of physicalism.


3.1) The paradox of phenomenal judgements: In order for the zombie-world argument to be valid, the zombies must behave exactly the same as us conscious humans do. This is because if he sticks to his argument that behaviour derives from psychological rather than phenomenal concepts (and the two can be logically separated) then it would certainly seem that our consciousness is irrelevant to behaviour.6 Now, in theory, in this zombie world there is also a Professor David Chalmers running around who argues for property dualism like the natural one does. This zombie judges (psychologically, not phenomenally) that he has consciousness and that this consciousness cannot be reduced to the physical facts. The zombie argues with people that he is consciously experiencing the world even though he isn't! In fact, what this paradox shows is that you would judge and believe that you were conscious whether or not you were...
Therefore we could argue that we do not know that we are conscious: for all we knowwe are zombies ourselves! Thus Chalmers' may have no evidence at all for his argument for dualism. This is his response:
"It might still be objected: "but the belief [that you have conscious experiences] would still have been formed even if the experience had been absent." To this I answer "So what?" In this case, I have evidence for my belief, namely my immediate acquaintance with [conscious] experience. In a different [zombie] case, that evidence is absent. ... [This] is not to say that the experience does not justify the belief in this case." (Chalmers, 1996, Page 198).
Now, I feel that Chalmers' has not given an adequate response: after all, both zombie and human would both think they know that they were conscious, regardless of whether they are right or wrong. Where then, is the evidence at all that we are conscious in a way that another physically identical being might not be? As Daniel Dennett puts it "If he suddenly lost his epiphenomenal qualia [conscious experience that is irrelevant to behaviour or essentially non-physical] ... he's still go right on saying he did have them." (Dennett, 1991, page 403)
Another form of the paradox runs like this: if our consciousness is meant to be irrelevant to our behaviour, then how can we talk about our conscious experience? If I talk about the beauty of an art piece surely my behaviour (the talking) is at least partially caused by my conscious experience of the art. But my zombie twin, who has not experienced the beauty would logically also talk about his experience of the beautiful art. Therefore it seems that consciousness is relevant to our behaviour and Chalmers' separation of the phenomenal concepts from psychology and human behaviour is flawed. He responds that our judgements about consciousness seem can be independent of our actual consciousness. So the referent of such judgments would then be the concepts of conscious states rather than conscious states themselves. As counter-intuitive as this is, it is a coherent answer - as it does not lead to a contradictory claim - though does seem quite bizarre.


3.2) Formal criticisms of property dualism: Dennett's "Consciousness Explained" was published five years before Chalmers' book. But he does offer criticisms of Jackson's argument and other zombie arguments similar to Chalmers'. To start with, Dennett seems to make some almost moral objections to any non-physical theories:
"There is a lurking suspicion that the most attractive feature of mind stuff is its promise of being so mysterious that it keeps science at bay forever. This fundamentally antiscientific stance of dualism is, to my mind, its most disqualifying feature, and its the reason why I adopt the apparently dogmatic rule that dualism is to be avoided at all costs. It is not that I think I can give a knock-down proof that all forms of dualism are false or incoherent, but that, given the way dualism wallows in mystery, accepting dualism is giving up."
"Are zombies possible? They're not just possible, they're actual. We're all zombies.7 Nobody is conscious - not in the systematically mysterious way that supports such doctrines as epiphenomenalism! I can't prove that no such sort of consciousness exists. I also cannot prove the gremlins don't exist. The best I can do is show that there is no respectable motivation for believing in it [my italics]." (Dennett, 1991, page 37; 406)
What he means he is that any theory of the nature of consciousness that resorts to non-physical facts is giving up on all explanation; and it is significantly complicating a theory unnecessarily (i.e. it flouts the scientific principle 'Occam's Razor': do not multiply entities unnecessarily). Of course philosophers such as Chalmers would respond that it is a necessary complication because of the immediate evidence for conscious experience as well as the non-logical supervenience of such from the physical facts of the world. This is why Dennett has proposed a materialist account of consciousness which would, in principle, if successful, prove zombies (in Chalmers' sense) to be logically impossible. We will return to this later.
Dennett also offers an interesting criticism of Jackson's knowledge argument:
"what [philosopher's such as Jackson] ask you to imagine is so preposterously immense that you cannot even [reasonably] try. The crucial premise is that "She has all the physical information." ... let me continue the story in a surprising - but legitimate - way:
And so, one day, Mary's captors decide it was time for her to see colors. As a trick, they prepares a bright blue banana ... Mary took one look and said "Hey! You tried to trick me! Bananas are yellow but this is blue!" Her captors were dumbfounded: How did she do it? "Simple", she replied, "You have to remember that I know everything that could be ever be known about the physical causes and effects of color vision. So of course before you brought the banana in, I had already written down, in exquisite detail, exactly what physical impression a yellow object, or blue object (or green, etc) would make on my nervous system. So I already knew what thoughts I would have ... Of course it's hard for you to imagine. It's hard for anyone to imagine the consequences of someone knowing absolutely everything physical about anything!"
" (Dennett, 1991, pages 399-400)
What is interesting about the Dennettian approach to consciousness is that there is no qualitative difference at all between conscious experiences and the physical facts about them. Dennett's criticism of the Mary-thought experiment has recognised the invalidity of using a thought experiment that we simply cannot imagine. In Philosophy, thought experiments are meant to help make a difficult point clearer or more easily appreciated; so clearly any thought experiment that cannot reasonably be apprehended is not much good. However the above passage alone does not disprove the validity of Jackson and Chalmers' argument. This is because Dennett has implicitly used the claim that phenomenal properties - and assumed phenomenal concepts - are in fact physical to justify the claim that Mary would have known what it is like to see red or blue. (Dennett first needs to justify the claim itself.) We will examine his materialist account of consciousness later but for now I will highlight an interesting passage where Dennett gives an descriptive example of how we could deduce what it is like from physical observations:
"Nagel [1974] claims that no amount of third-person knowledge could tell us what it is like to be a bat, and I flatly deny that claim. ... [For example] just what are the resolution limits of a bat's echolocation? Is it used to identify objects at all, or just an alerter and tracker for capture? Would a bat be able to distinguish pinfeathers spread from pinfeathers closed just using echolocation? I doubt it, but we will have to design some experiments to see. ... The sorts of investigation suggested by such an exercise would take us a long way into an account of the structure of the bat's perceptual and behavioural world, so we could rate heterophenomenological narratives8 for realism ... For example we would learn that bats would not be bothered by the loud squeaks they emit, because they have a cleverly designed muscle that shuts down their ears in perfect timing with their squeaks." (Dennett, 1991, pages 442-443)
So Dennett believes that we could, in principle, know 'what it is like' purely from physical observations: clearly this stands in direct criticism of Jackson's knowledge argument. But can this be applied to phenomenal concepts (what the world subjectively feels like) as well as perceptual concepts (what something is or is not aware of)? I'm not convinced; for example, imagine how difficult it would be for a colour-blind or deaf person to imagine what it is like to see a colour or hear a sound respectively. The problem is, is that our conscious experiences - whatever they actually are - are within our private, introspective, subjective, mental description of the world: I do not think it is even meaningful to approach these experiences extrospectively, such as in a scientific experiment. Surly the way we perceive the world consciously or privately is qualitatively different to how we see it factually?
I am not alone here, David Papineau (2002) is equally critical of Dennett's approach. According to Papineau, Mary's mind would never have the knowledge of what it is like to see red until she does: the optical receptors would not have had the necessary stimuli.
"Mary's new experience will enable her henceforth [my italics] to re-create this experience in imagination, and in addition [she will be able to] classify new experiences introspectively as of the same kind [i.e be able to recognise other objects as being 'red']." (Papineau, 2002, page 53)
Now Papineau is a materialist (property and substance) just like Dennett, but does argue for 'conceptual dualism'9 whereby phenomenal concepts are perceived as qualitatively different to material concepts. He uses conceptual dualism to explain 'the intuition of distinctness'; he argues that conceptual dualism can explain why most of us feel that Mary does seem to learn a further fact when she sees a red object: it is because a priori (i.e. conceptually) the material and phenomenal properties are distinct; however Papineau does argue that a posteriori analysis shows that they in fact have the same referents (i.e. he is a property materialist).
"We might say that the difference between phenomenal and material concepts is a difference at the level of sense, not reference," (Papineau, 2002, page 49)
Papineau begins his book "Thinking about Consciousness" by explaining the classic 'causal argument' for materialism. This shows that our conscious mind is part of the causal flux of the natural, physical, world. He was kind enough to summarise it into one paragraph:
"Many [or all] effects that we attribute to conscious causes have full physical causes. But it would be absurd to suppose that these effects are caused twice over. So the conscious causes must be identical to some part of those physical causes." (Papineau, 2002, page 17)
To help appreciate this approach, consider this example: I chose to go to the fridge because I have a conscious experience of thirst. It follows that a key cause of my going to the fridge is my conscious experience (I would not have gone if I had not wanted a drink). But biologists and cognitive scientists know that our behaviour is caused by physical causes, for example the chemical activity in our brains or the reaction of various cognitive processes. So if all our behaviour has physical causes, and in some cases our behaviour has conscious causes, it follows that such conscious causes are themselves physical. In this way, Papineau attempts to demonstrate that our consciousness consists of fully physical causes. He describes the causal argument as "the canonical argument for materialism" and it does seem very compelling. The main weakness to it, it seems to me, is that is does not sufficiently explain why we should have phenomenal concepts at all. Prima facie10 it would seem that human behaviour (which is all that really matters in terms of evolutionary biology) could remain identical even if our phenomenal concepts were removed; or, more precisely, if our awareness of our phenomenal concepts was removed. We return to the zombie argument.
We are now in a position to identify the tasks for the materialist: why is awareness of phenomenal concepts (i.e. consciousness) necessary for a biological human? Indeed what are the phenomenal concepts themselves for? Why might natural selection favour organisms with consciousness? And how can we reductively explain consciousness in terms of physical facts?


4) A materialist's account of consciousness:


4.1) A Dennettian approach: Dennett has provided a materialist account of consciousness in Consciousness Explained called the 'Multiple Drafts Model (MDM)' (1991). The MDM runs like this:
"Here is a first version of the replacement, the Multiple Drafts model of consciousness. I expect it will seem quite alien and hard to visualise at first - that's how entrenched the Cartesian Theatre idea is [the idea that judgements and concepts must be presented to one point or final line in the brain to some "observer"]. According the the Multiple Drafts model, all varieties of thought or mental activity (including perception) are accompanied in the brain by parallel, multitrack processes of interpretation and elaboration or sensory inputs. Information entering the nervous system is under continuous "editorial revision." For instance, since your head moves a bit and your eyes move a lot, the images on your retinas swim about constantly, rather like the images of home movies taken by people who can't keep the camera from jiggling. But that is not how it seems to us. ...... We don't directly experience what happens on our retinas. What we actually experience is a product of many processes of interpretation - editorial processes, in effect. ... now we are poised for the novel feature of the Multiple Drafts model: Feature discriminations only have to be made once, the information content thus fixed does not have to be sent somewhere else to be rediscriminated by some "master" discriminator; there is no Cartesian Theatre.
These specially and temporally distributed content-fixations in the brain are precisely locatable in both space and time [at least in principle], but their onsets do not mark the onset of consciousness of their content. It is always and open question whether any particular content thus discriminated will eventually appear as an element of conscious experience, and it is a confusion to ask when it becomes conscious. These distributed content-discriminations yield, over the course of time, something rather like a narrative stream or sequence ..." (Dennett, 1991, pages 111-113)
So according to Dennett, our conscious experience is simply the general feel of the overall effect of hundreds of mental judgements (deriving primarily, or solely, from sensory reception). There is no particular observer as an extra item; rather an "observer" is the general group of judgements, e.g. in one brain.11
"When a portion of the world [e.g. a human brain] comes in this way to compose a skein of narratives, that portion of the world is an observer. That is what it is like for there to be an observer in the world, a something it is like something to be." (Dennett, 1991, page 137)
This model has support of empirical evidence that there are many parallel judgements going on in the brain in respect to sensory reception (e.g. Julesz, 1971; McGurk and Macdonald, 1976). However this presents a rather complex, long-winded approach to consciousness; and still leaves some difficulties. Why indeed should a composition of narratives, a cluster of judgements, lead to conscious phenomenal experience anyway? Consider a basic robot programmed with many commands - including 'dance when around people', 'smile', 'high five people', 'comfort people who are behaving as if they are sad', 'get on with your work enthusiastically' etcetera - all of which give the behavioural impression of feeling happy; should we then conclude that the robot does personally, subjectively, feel happy, experience joy? No I do not see why so. Even if each of such commands were copied many times, and edited in respect to each new situation the robot meets (continuously, or every minute say), there does not seem to be any reason to suppose that the robot experiences joy - it merely behaves in a similar way to how a human might behave when she has a conscious feeling of joy. As Chalmers (1996) notes, in respect to Dennett's (1991) theory:
"This is an elegant argument, with a ring of plausibility that many reductionist arguments against consciousness lack. But its elegance derives from the way it exploits a subtle ambiguity in the notion of "seeming," which balances on the knife-edge between the phenomenal and psychological realms. There is a phenomenal sense of "seem," in which for things to seem a certain way is just for them to be experienced a certain way. And there is a psychological sense of "seem," in which for things to seem a certain way is for us to be disposed to judge that they are that way. It is in the first sense that a theory of experience must explain the way things seem. But it is in the second sense that Dennett's theory explains it." (Chalmers, 1996, page 190)


4.2) On awareness: Most of us feel that it is fairly intuitive that awareness is closely related to conscious states: it is hard to comprehend the idea of being conscious of something but unaware of it. You are surely aware of even conscious items in your peripheral vision or background noise; maybe not focally12 aware but in as much as you are conscious of something, you seem to be as aware of it with close correlation. But we should have learnt by now to be sceptical about our intuitive beliefs (as the Cartesian fallacy demonstrates). Jesse Prinz (2003) has provided some empirical evidence for the claim that awareness is closely linked to consciousness:
"[In cases where patients suffer from hemispacial neglect] right inferior parietal injuries prevent patients from attending to the left side of their visual fields or the left side of visually presented objects, or the left side of their own bodies. They report no conscious experience of things on the left. ... Nevertheless, there is evidence that patients with neglect are still registering information about the objects that they fail to experience (Marshall and Halligan, 1988; Bisiach, 1992; Driver, 1996). ... There is every reason to think that patients with neglect are capable of perceiving, to some degree, without conscious experience. This shows that mere activity in a perceptual system is not sufficient for consciousness. [Further] conscious experience of the left side is lost as a result of injuries in centres of the parietal cortex that have been independently associated with attention: Neglect is an attention disorder. This suggests that consciousness requires attention [my underline]. This hypothesis gains [further] experiential support from behavioural studies with normal subjects. Evidence suggests that people will fail to consciously perceive a centrally presented object if their attention is occupied by another task. The phenomenon was labelled 'inattentional blindness' by Mack and Rock (1998). In their studies, many subjects fail to [consciously] notice a centrally presented object that is briefly displayed, and unexpected. ... Some researchers object to the thesis that attention is necessary. For example: staring at a solid expanse of color, spanning the entire visual field. Do we really need to attend to experience the hue? I think the answer is yes. Contrary intuitions stem from the fact that attention is often associated with effort and focus. In this case, however, attention is spread evenly across the field; or perhaps it bounces around, as if scanning fruitlessly for points of interest. In either case, attention may not require [much] effort. It does, however, involve selection." (Prinz, 2003)
When Prinz talks about attention, he refers to a selection process that allows information to be sent to outputs for further processing. He then suggests that attention allows perceptual information to access working memory stores. He goes on:
"'Working memory' refers to our ability to retain information for brief periods of time, and to manipulate it in various ways. ... When we perceive, what we perceive is made available for temporary storage. Attention is gate keeper to working memory.
If all this is right, the solution to the How Problem can be stated: consciousness arises when intermediate-level perception13 representations are made available to working memory via attention. I call this the AIR theory; attended intermediate-level representations. The suggestion that working memory access is important for consciousness has many defenders (e.g. Baars, 1997; Rees, 2001)...
It should be evident that consciousness is extremely valuable if the AIR theory is right. Consciousness serves the crucial function of broadcasting viewpoint specific information into working memory. Viewpoint specific representations are important for making certain kinds of decisions. If we encounter a predator, for example, it is useful to know whether it is facing us or facing another direction. Consciousness provides us with this information by making it available to working memory. Working memory is the store from which decisions are made and actions chosen. Without working memory, we would be reduced to reflexive responses. There is also evidence that working memory is a gateway to episodic memory (Buckner et all, 1999). ...
It might be objected that functions I have been describing could be achieved without consciousness. In another possible cognitive system, viewpoint specific representations could be broadcast to working memory without any experience or phenomenology. This is perfectly true, but the 'could' renders the point irrelevant. [For example] fly swatters serve the function of swatting flies, but so could an insect-eradicating lamp..." (Prinz, 2003)
...but it would be ludicrous to suggest that therefore the electricity in the lamp was unnecessary for the function of killing flies. Similarly our consciousness should not be denied their cognitive function just because the same function could have occurred without it via another system.
Prinz's theory certainly comes a long way towards a coherent, evidential and straightforward reductive theory of consciousness. And he has implicitly answered the question of why natural selection would favour creatures with consciousness. For Prinz, 'consciousness' is the attention given to intermediate-level perceptual subsystems for the function of working memory.
But can this 'attention' be further reduced? I think so. Further it remains a tiny bit unclear why such attention, that Prinz describes, should lead to phenomenal experiences - it seems easy to imagine that a robot could 'select' the relevant information from it's perception and manipulate it in its memory banks without actually experiencing anything, I think this would be a good route to follow to further defend physicalism from the challenge of consciousness. It might too be noted that some of Prinz's theory rests upon inconclusive empirical evidence and so the theory itself is potentially vulnerable; so a more rationalist, general and simple model of consciousness may well be preferable (maybe not for the scientists but certainly for the philosophers!)


4.3) On representation and mental concepts: Firstly, what exactly is the constitution of a phenomenal concept? Uriah Kriegel (2009) argues:
"The answer lies in a certain natural conception of phenomenal character. When I look at the white wall to my right, I have a conscious experience of the wall, and there is a whitish way it is like for me to have that experience. This "whitish way it is like for me" constitutes the phenomenal character. Plausibly there are two discernible components to this phenomenal character. One is the "whitish" component; the other is the "for me" component. We may call the former qualitative character [the various sensuous qualities it involves, depicted by our perceptual senses] and the later subjective character [i.n respect to the individual who is enjoying the conscious state]. ... phenomenal character is rightly thought of as the compresence of qualitative and subjective character." (Kriegel, 2009)
A conscious state, and the representation of such, resides in the subject. It seems clear that any form of awareness requires reference to a representation. Similarly, any mental conscious experience would seem to require reference to a mental representation of 'what it is like'.
"For me to be aware of a tree [consciously or not], I must have a mental representation of it. Likewise for inner awareness [consciousness]: subject S is aware of a conscious state C only if S has an inner representation of C. ... [Further,] since subjects represent things by harboring mental representations of them we form the thesis:
'For any conscious state C of a subject S, there is a mental state M, such that S is in M, and M represents C'" (Kriegel, 2009).
A prima facie difficulty could be phrased:
If S is aware of C in reference to M, then does S also need an M* to refer to M, then an M** to refer to M*, and so on ad infinitum?
Now, Kriegel defends a form of self-representationalism to fix this difficulty. Essentially, Kriegel suggests that we should let M = C; let the mental concept of the conscious state be numerically identical, not distinct, to the conscious state.
"For any conscious state C of a subject S, there is a mental state M, such that S is in M, M represents C and M = C" (Kriegel, 2009)
In this way, the conscious state is represented by a mental state and by itself, because the mental state and the conscious state are identical. The conscious state represents itself (hence 'Self-representationalism').


4.4) And this means...: We could argue that all that is needed to explain phenomenal consciousness is to explain phenomenal concepts. It seems to me that this conclusion becomes clear once we accept the inflationist stance of Papineau.
These phenomenal concepts are surprisingly easy to explain. The brain forms and store pockets of information (concepts) of what things are like. Then the brain has only to refer to such concepts and form judgements in respect to them.
If it were argued, "That only explains the functional concepts, the dispositions to certain behavioural judgements; not the experiences themselves", I would reply "Ah ha! Now I can see the flaw in your logic.14 You seem to think that there is a difference between attending to a phenomenal concept and experiencing a phenomenon: there isn't."
A phenomenal concept is a mental image or map - or a categorised web of information - of what something is like. Attending to the concept and having an experience are equivalent; after all, your only "experience" of the world can only ever be through mental interpretation of sensory information.15 Therefore "zombies" are logically impossible since a biological homo-sapien brain necessarily has and can form these phenomenal concepts and attends to them.
We have evolved these, very simply, because we need to be able to navigate the world and recognise differences and similarities in the sensory reception of objects. If we know what something is like, we can recognise it or similar things. If we had no phenomenal concepts our species would have no chance!
For example, if we have (or can form) a phenomenal concept of the pain sensation from falling or tripping over and hitting the ground, then we would sensibly avoid jumping off too high things. Or if we have a phenomenal concept of the joys and feelings of happiness from eating, socialising, playing sports and having sex, then we will pursue those activities. Without such concepts we could not know, remember or introspect16 on what these things are like - which would have obvious evolutionary drawbacks.


4.5) Applications: By this approach to consciousness, it is plausible that other creatures, indeed other humans, may have different experiences of the world. If we subjectively form our own phenomenal concepts based on sensory reception and other pre-existing judgements then we may each form significantly different phenomenal concepts. For example many of us hate being pummelled; but hardened thugs or even rugby players may feel a pleasant rush from being pummelled. Or more positively, for many people writing essays is horrible and boring - that is what it is like for them - but for people who (forcibly or voluntarily) get involved in it, writing essays or other intellectual pursuits are very fulfilling.
On strong A.I: could a machine be conscious? I see no reason at all why not. On this approach to consciousness, a robot need only be able to form, and judge, concepts of what things are like. In a human brain, our experiences consist of a giant complex of hundreds of judgements and revisions in respect to awareness of phenomenal concepts so that a robot would have to be programmed incredibly thoroughly - layer on layer - to produce conscious experience anywhere near as rich as ours; but I do not think it is in principle impossible.


4.6) On the unity of consciousness: The only remaining difficulty with this approach to consciousness is the query of why we individual experience the whole as a unity, as a 'self'. Let's return to Descartes argument, 'Cognito ego sum', which claims that we can identify the 'self' via introspection on our thinking self. The immediately apprehended state that I am thinking (or doubting one's own existence) proves that there is an 'I' which is thinking or doubting. But note the logical fallacy here: 'I think; therefore I am' is begging the question because the conclusion is already assumed in the premise. As the 18th century philosopher Georg Lichtenberg notes:
"The only thing we know is the existence of our sensations, ideas and thoughts. We should say 'it thinks', just as we say [of lightning] 'It flashes'. To say 'cognito' is already to have gone too far, if we translate it as 'I think'." (Sudelbucher, K 76)
Further, the empiricist philosopher, David Hume explains:
"When I turn my reflexion on myself, I never can perceive this self without some of more perceptions; nor can I ever perceive any thing but the perceptions. 'Tis the composition of these, therefore, which forms the self." (Hume, 1739)
Hume's understanding of the self here may need some development from merely 'the composition of perceptions', since is seems clear to each of us (I guess) that these perceptions not only form a complex, but they are also observed by one observer. Why so? Let's see if Dennett's notion of the self as analogous to animal behaviour provides any helpful suggestions:
"This fundamental biological principle of distinguishing self from the world, inside from outside, produces some remarkable echoes in the highest vaults of our psychology. ... For example, would you please swallow the saliva in your mouth right now? This act does not fill you with revulsion. But suppose I had asked you to get a clean drinking glass and spit into the glass and then swallow the saliva from the glass. Disgusting! But why? It seems to have to do with our perception that once something is outside of our bodies it is no longer quite part of us anymore - it becomes alien and suspicious ...... In Homo sapiens, each normal individual of this species makes a self. Out of its brain it spins a web of words and deeds [a 'web of discourses'], and like other creatures, it doesn't have to know what it is doing; it just does it. This web protects it, just like the snail's shell, and provides it a livelihood, just like the spider's web, and advances its prospects for sex just like the bowerbird's bower[!!]. ... like a beaver it works hard to gather the materials out of which it builds its protective fortress. ... So wonderful is the organization of a termite colony that it seemed to have some observers that each colony had to have a soul (Marais, 1937). We now understand that its organization is simply the result of a million semi-independent little agents. [Similarly] so wonderful is the organization of a human self that to many observers it seemed that each human being has a soul." (Dennett, 1991, pages 414-416)
But if the self is a creation of the individual human brain, then who is it doing the creating? Are we just natural effects of mindless nature? Maybe, as counter-intuitive and emotionally uncomfortable this may be, it seems to be a coherent theory. Of course once the basic 'self' is created, it becomes its own agent which can control its own behaviour and thoughts17. Dennett provides evidence to show how the self is not a fixed discrete item but rather a subjective creation which can therefore be reformed at will:
"Do we expand our personal boundaries - the boundaries of our selves? In general, perhaps, no, but there are certainly times when this seems true, psychologically. For instance, while some people merely own cars and drive them, others are motorists; the invertebrate motorist prefers being a four-wheeled gas-consuming agent to being a two-legged food-consuming agent, and his use of the first-person pronoun betrays this identification:
"I'm not cornering well on rainy days because my tires are getting bald"
So sometimes we enlarge our boundaries; at other times, in response to perceived challenges, we let our boundaries shrink:
"I didn't do that! That wasn't the real me talking. Yes the words came out of my mouth, but I refuse to recognise them as my own." " (Dennett, 1991, page 416-417)
On one plausible physicalist theory at least, we can explain the unified self in terms of - what I prefer to call - 'value judgements'. What I mean is that the different concepts in our mind are essentially distinct; not unified. But that in our minds there exists more judgements; which value (to value is a form of judgement) other concepts to be more or less part of one agent. There may be a judgement p which values concept c, or the group of concepts g, to be part of the wider self S. The self then identifies itself; in terms of the compositions of such concepts (Hume's perceptions).18


5) To Conclude: I do not claim to have given a complete or even necessarily correct physicalist account of consciousness but do I hope to have noted some reasonable suggestions at least. My main task, however, was to show that the phenomenon of consciousness is no call for non-physical facts; which I do feel I have done. I feel that the most important and critical claim in this essay was that attending to a phenomenal concept and experiencing a phenomenon are identical. My whole argument will fall apart if this is disproved.
So... "Consciousness is at once the most familiar thing in the world and the most mysterious." (Chalmers, 1996, page 3) ...
Well I certainly agree with the first claim, in fact my entire familiarity of the world is mediated through my consciousness. But it is mysterious? I think not. I think the confusion and sense of mystery derives from an over-reliance on our intuitions that, for example, I am not my body or that I am a particular, definite item. Once these intuitions are overcome the sense of mystery vanishes.


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