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The phenomenal quality of experience constitutes an irresolvable difficulty for the functionalist theory of mind. Discuss.

Functionalism is the theory which argues that states of mind are merely descriptions of the function which such a 'mental state' produces - so to say someone is in pain means that they will attempt to remove themselves from the position that is producing the pain, and prevent themselves getting into a similar position again. Functionalism, therefore, requires a closed materialist system, where a set of stimuli will produce the same response, and that only these stimuli will interact - that is there will be no interactions external to the physical configuration of the body. This closed system can be a black-box system, where what is going on 'inside' need not be known, all that is important is that what comes out the other side is entirely dependent on what goes in (or, of course, fails to). Functionalism argues, therefore, that 'mental states' can be described entirely in terms of physical facts about the brain, though it is perfectly possible that we are not yet aware how these complex interactions work; it does not allow 'mental states' to be associated with a mind, since clearly if they were they would consist in more than just a particular function - namely they would be a particular event in the history of that mind.

The reason, therefore, that qualia - the name given to the actual experience of having a 'mental state' - are so damaging to the functionalist theory of mind is that they suggest that there is an additional aspect to having a particular mental event occur. Rather than it just producing certain electro-chemical events in the brain, which serve to produce a particular reaction, it appears that we are actually able to experience an event, to feel things which we would not have felt had the event not occurred.

What Mary Didn't Know

In his essay 'What Mary Didn't Know' Jackson uses the example of a scientist, Mary, who is locked in a room where everything (including herself) is painted black or white. Mary has done extensive research into colour, and knows a very great deal about how it works - in fact she knows far more than the vast majority of people. It appears to be the case, however, that Mary is still missing the most important knowledge about colour - she doesn't know what colours look like. The question this brings up for those who do not believe in qualia is how they would account for the genuine surprise and excitement Mary would feel when she is finally allowed out of the room, and able to experience colour first hand for the first time. We surely have to admit that she would be doing something new - feeling something new - when she was able to know finally what red looks like.

There seems to be a problem with this analysis, however. If we are seriously suggesting that Mary is simply lacking a mental property, and not just some physical property of her brain, then why do we need to make such an overtly physical effort to change the room that she is in? Mary isn't just lacking the experience of seeing colour, she hasn't seen colour, because we've physically prevented her by eliminating anything other than black and white from the room. It might be argued that this is the only way that we could prevent her from having the experience of seeing colour, but this surely isn't going to be an argument in favour of qualia as distinct from physical properties, but will assert the fact that qualia rigorously accompany certain physical causes and effects, such as stimulation of cones in the eye, or the firing of certain neurons - albeit a possibly contingent fact. Other possibilities do exist for placing Mary in the same state of never having had the experience of colour, but these too (such as altering her cones, or blinding her) are entirely physical. It seems to be the case that we can convey the situation that Mary is in in a way that is comprehensible by those who have experienced colour - we simply need to say that she is in the state where she is not in the physical configuration produced by exposure to colour - and indeed Mary would be able to outline very specifically what this configuration would be like in terms of cones and neurons.

This does not, however, seem to be a fair assessment. Whilst I think it is perfectly possible to imagine life without colour (after all, we've all had experiences of black and white films), and we could bring this to mind by being told about Mary locked in her room, and told to imagine what it would be like to have the physical configuration brought about by her captivity, this does not work the other way round. Even if Mary were told to imagine having the physical configuration of those living outside her room, this would put her no closer to understanding the experience of those people. She would simply be able to visualise certain bits of her eyes becoming active in some way, or different electrical impulses moving around her brain, but none of this would actually indicate to her how such an experience would actually feel. To know how it would feel it appears to be the case that she would have to experience it.

Churchland also comes up with a very interesting response, saying that the Knowledge Argument (as the ideas suggested by 'What Mary Didn't Know' are known) proves too much. He uses a response that doesn't address what the problem with the Knowledge Argument is, but simply suggests that we cannot accept it because of the counter-intuitive conclusions we must reach if we do so. What Churchland points out is that during the time that Mary is locked in her room, she need not watch television programmes only about neurology, but may also watch ones about dualism, and yet even if Mary learns everything about the mental she still won't know what it is like to experience colour - and the conclusion that Churchland suggests we must draw from this is that qualia are therefore neither physical nor mental, but something else entirely. At the very least, Churchland suggests, we cannot claim that qualia are non-physical on the basis that regardless of how much knowledge about the physical we have we will never know about qualia without denying that qualia are not mental by exactly the same reasoning.

Jackson's response to Churchland does not seem entirely satisfactory. He says that the reason this does not disprove his argument is that Mary won't know all the mental facts when she is trapped in the room, and whilst (he claims) you can learn all physical facts on television, you cannot learn all mental facts in the same way - and if Mary can't know all the mental facts whilst in her prison, then she won't know all the mental facts and yet still have missing knowledge about what it is like to experience colour. This doesn't seem satisfactory mainly because if we are going to say that Mary simply won't be acquainted with certain facts it seems just as acceptable to suggest she won't know all the physical facts as to suggest that she won't know all the mental facts - and the fact (as I have remarked) that in experiencing colour she will be subject to physical changes that she has not been subject to when imprisoned adds weight to this claim, so we should not be satisfied with an explanation that simply makes the (seemingly vacuous) claim that when she leaves the room and has a new mental event she has a new mental event. Why can Jackson claim that it is not possible to learn all mental facts on television but that we can know all physical facts? Surely the materialist can simply say that it had seemed like we could learn all physical facts from a television programme, but that since we can't learn about qualia (which a materialist claims to be physical) we cannot. I doubt very much a materialist would want to go down this line of argument, since people could simply agree with Churchland, and say that evidently qualia are both non-physical and non-mental (as counter-intuitive as this might seem, and as empty as it would leave the set of mental things), and clearly the materialist does not want to accept this conclusion, so they still have some way to go to prove that qualia can be reduced to physical facts - and a response than analyses the problem with the Knowledge Argument rather than simply showing that there is one would seem likely to be more useful.

Lewis agrees that when Mary leaves the room and experiences colour for the first time she learns something new, but he says that there's learning and there's learning. Since philosophers arguing about qualia seem to be trying to prove that there is a new type of fact, other than physical facts - a new type of propositional, fact-implicating knowledge (as Lipton puts it) - the sort of knowledge that Mary needs to learn when leaving the room needs to be about facts. Lewis, however, suggests that she doesn't learn any new facts, but achieves a different sort of learning, and not one that will prove that there is a different type of fact or even a different type of any 'stuff'. What she has learnt is how to know when she is seeing red - she has learnt know-how, not know-that. This is an interesting response, and Lewis has certainly made some headway by specifying exactly the sort of thing we will need to prove if the Knowledge Argument is going to be a serious problem for functionalism - namely that there is another type of fact and that an analysis of the world simply in terms of physical 'stuff' is not a complete description. Unfortunately for the materialist, I think Lewis is being a little quick to dismiss all that Mary has learnt as know-how; surely she has also learnt know-that, namely she has learnt what it is like to experience colour.

The Maxwell House Coffee Tasters

Can we, then, show that there is additional know-that knowledge gained from experience, on top of the the know-how? Dennett describes the imagined story of two coffee tasters at Maxwell House discussing their experiences, and how they feel their jobs have changed. One claims that in the time he has been working there, the taste of the coffee has changed, and whilst he liked the original taste, he doesn't like how it now tastes; the other, meanwhile, claims that the coffee still tastes just the same as when he first arrived at his job, but that he can no longer stand the stuff, probably out of boredom at the same taste day-in, day-out. The claim is that a functionalist is unable to make a distinction between these two positions, since they both involve the same result, and presumably disliking coffee because it has changed its taste and learning to dislike its original taste will produce just the same functionalist responses. I'm not sure that this example is an entirely fair attack on functionalism. The first part of it that I would take issue with is the suggestion that feeling that the taste has become unpleasant and believing that the coffee has a new unpleasant taste have functional equivalence, which surely they do not. We do not view tastes as simply either nice or unpleasant - we take them to be a complex set of different sensations, and it is perfectly possible that we could learn to like or dislike a taste without the other aspects of the taste changing in much the same way that someone can become desensitised to pain if they are often exposed to it - and if this were to be the case then we might well react differently to these two possible changes.

There is, however, a more interesting point to be examined with this example - especially with the question of whether qualia account for knowledge-that - that of what it would be for the 'same' coffee to taste different. We presumably do view the person that argues that the coffee is 'the same' but that he doesn't like it anymore as saying something sensible, yet in what way could the coffee be 'the same' if it now evokes a different response? One answer would be to claim that the coffee continues to be manufactured in the same way, so Maxwell House is still creating the same product, and in this sense nothing has changed, but I don't think this is what is meant. What presumably is meant is that the coffee still has the same taste - which might well accompany the same manufacture, but need not (due to fluctuations in the raw beans, or changes in other factors, such as the composition of the air it is created in). Most probably we consider anything with exactly the same chemical make-up to have the same taste, and this instinct is presumably correct. The reason that this is of particular interest is that it appears to be the case that we see foodstuffs as each having an intrinsic taste, which, whilst they may be interpreted subjectively, are based upon something objective. When people argue that something's taste has changed it seems to be the case that this could be a simple, objective fact, without regard to the question of whether anyone has realised it. We can well imagine a situation where something changes its taste without anyone being aware of it - such as simply when nobody has tasted something; we seem to regard things as having an ability to produce a certain taste reaction, rather than simply having taste when people are indeed tasting them.

Dennett also uses the even clearer example of rooms seeming to be smaller as we grow up. Everyone has experienced the feeling, on entering a room that you have not seen since you were small, that it has shrunk dramatically since you were last there - yet this is clearly explainable in terms of your size relative to it, and that it no longer takes ages to get from one side of the room to the other, and nor does the idea of someone banging their head on the door frame seem absurd anymore. So it does seem to be the case that, on top of the actual physical know-that facts, there are certain experiential know-that facts, such as how something tastes, how big a room seems, and what it is like to experience a certain colour.

What is it Like to be a Bat?

In his article 'What is it Like to be a Bat?' Nagel discusses just this sort of know-that knowledge that Lewis is suggesting that Mary gains when she leaves the room. When imagining being a bat, Nagel suggests, we don't just imagine being a certain size, having various physical properties, being blind, etc. but also believe that there is something that it is like to be a bat; that a bat has a particular sort of experience and that these non-physical facts, these qualia, prove that we cannot explain what makes bats different from us simply in terms of the physical, but must also consider the ways in which they feel different. This is a very interesting thesis, and does sound very plausible - if we concede that bats have a different sort of experience from us (and presumably, considering that they navigate principally by sonar rather than sight would not be a difficult concession, unless we stubbornly insist that this is a simple substitution, and that sonar simply fills exactly the gap left by their blindness) it seems to be the case we should admit that there is a significant difference between what it is like to be human and what it is like to be a bat; and physical descriptions seem ill-equipped to account for 'what it is like to be's. One materialist response will presumably be that it is a little strange for the opponent of functionalism to use the difference between a bat and a human to illustrate that a change in a mental experience is possible entirely divorced from any physical change when of course bats are so different physically from humans. The difficulty with this response is that whilst the materialists may well be able to argue that on every occasion we have observed a mental change it is accompanied by a physical change, to remove the problem of qualia we must be able to say that they are identical with the physical, rather than simply being related by a connection that is in some way contingent.

Contingency and Identity

How do we account for the seemingly vital correlation of a particular physical activity with a particular qualia? If these things are indeed inseparable, then it does seem a likely possibility that they are just two aspects of the same thing, and whilst different ways of referring to an event, in fact they are the same event - namely that they are two senses of the same reference. If, however, they are only contingently bound together, and in fact are separable concepts, qualia must be independent of any physical facts, and able to be experienced regardless of them.

Kripke puts it that if A is a rigid designator by having an intrinsic property x and B is a rigid designator by having an intrinsic property y, then if x is different from y then A is not strictly identical with B. Since the intrinsic property of an experience - how it actually feels - is not the same as the intrinsic property of the physical configuration that usually accompanies such a feeling - certain physical facts - it can't be that experiences simply are physical occurrences in the brain. But an objection such as this seems to be mistaking functionalism for behaviourism, which says that a 'mental state' is simply the behaviour that it causes to be exhibited, rather than a 'mental state' provoking the behaviour that is exhibited as functionalism argues - so to be in pain is to act in a certain way, rather than being in pain making you act in a certain way. Functionalists, therefore, may be able to agree with the claim that certain 'mental states' only contingently correlate with physical states, but this is may not be a criticism - in fact it could be in functionalism's favour, because functionalism would allow other things than brains to display mental characteristics.

Overall, therefore, I am not convinced that functionalists have come up with a completely adequate response to the dualists' qualia-based attack, and qualia seem to offer substantial problems for a materialist account of people and, indeed, the world. Perhaps I would place myself in the category of an unwilling epiphenomenalist, believing that qualia are simply a byproduct of brain-activity, but hoping that we will find a better way of explaining them away. Churchland's response seems fair to me, and, as un-diagnostic as it would seem to be, it does seem to show that we may be utterly unable to explain what sort of thing qualia are. It certainly would seem to take a great deal of arrogance to suggest that there is an extra sort of stuff just for us - that we, as mental, experiencing beings have a whole different universe open to us. If we are going to accept qualia, must we, as Churchland suggests, accept any number of other types of stuff? Surely we should accept that chairs could have some type of stuff associated with them that we cannot understand, or at least 'weird' things such as black-holes, or time - any of which would make for a much stranger (and far fuller) universe than we currently imagine, and might seem a bizarre consequence of accepting a woman seeing colour for the first time as learning something new.