Archive for April, 2015

knight 3This is the third in a series of four posts about key ideas from my book The Shadow of Consciousness; this one is about haecceity, or to coin a plainer term, thisness. There are strong links with the subject of the final post, which will be that ultimate mystery, reality.

Haecceity is my explanation for the oddity of subjective experience. A whole set of strange stories are supposed to persuade us that there is something in subjective experience which is inexpressible, outside of physics, and yet utterly vivid and undeniable. It’s about my inward experience of blue, which I can never prove is the same as yours; about what it is like to see red.

One of the best known thought experiments on this topic is the story of Mary the Colour Scientist. She has never seen colour, but knows everything there is to know about colour vision; when she sees a red rose for the first time, does she come to know something new? The presumed answer is yes: she now knows what it is like to see red things.

Another celebrated case asks whether I could have a ‘zombie’ twin, identical to me in every physical respect, who did not have these purely subjective aspects of experience – which are known as ‘qualia’, by the way. We’re allowed to be unsure whether zombie twin is possible, but expected to agree that he is at least conceivable; and that that’s enough to establish that there really is something extra going on, over and above the physics.

Most people, I think, accept that qualia do exist and do raise a problem, though some sceptics denounce the entire topic as more or less irretrievable nonsense. Qualia are certainly very odd; they have no causal effects, so nothing we say about them was caused by them: and they cannot be directly described. What we invariably have to do is refer to them by an objective counterpart: so we speak of the quale of hearing middle C, though middle C is in itself an irreproachably physical, describable thing (identifying the precisely correct physical counterpart for colour vision is actually rather complex, though I don’t think anyone denies that you can give a full physical account of colour vision).

I suggest we can draw two tentative conclusions about qualia. First, knowledge of qualia is like knowledge of riding a bike: it cannot be transferred in words. I can talk until I’m blue in the face about bike riding, and it may help a little, but in the end to get that knowledge you have to get on a bike. That’s because for bike riding it’s your muscles and some non-talking parts of your brain that need to learn about it; it’s a skill. We can’t say the same about qualia because experiencing them is not a skill we need to learn; but there is perhaps a common factor; you have to have really done it, you have to have been there.

Second, we cannot say anything about qualia except through their objective counterparts. This leaves a mystery about how many qualia there are. Is there a quale of scarlet and a quale of crimson? An indefinite number of red qualia? We can’t say, and since all hypotheses about the number of qualia are equally good, we ought to choose the least expensive under the terms of Occam’s Razor; the one with the fewest entities. It would follow from that that there is really only one universal quale; it provides the vivid liveliness while the objective aspects of the experience provide all the content.

So we have two provisional conclusions: all qualia are really the same thing conditioned differently by the objective features of the experience; and to know qualia you have to have ‘been there’, to have had real experience. I think it follows naturally from these two premises that qualia simply represent the particularity of experience; its haecceity. The aspect of experience which is not accounted for by any theory, including the theories of physics, is simply the actuality of experience. This is no discredit to theory: it is by definition about the general and the abstract and cannot possibly include the particular reality of any specific experience.

Does this help us with those two famous thought experiments? In Mary’s case it suggests that what she knows after seeing the rose is simply what a particular experience is like. That could never have been conveyed by theoretical knowledge. In the case of my zombie twin, the real turning point is when we’re asked to think whether he is conceivable; that transfers discussion to a conceptual, theoretical plane on which it is natural to suppose nothing has particularity.

Finally, I think this view explains why qualia are ineffable, why we can’t say anything directly about them. All speech is, as it were, second order: it’s about experiences, not the described experience itself. When we think of any objective aspect, we summon up the appropriate concepts and put them over in words; but when we attempt to convey the haecceity of an experience it drops out as soon as we move to a conceptual level. Description, for once, cannot capture what we want to convey.

There’s nothing in all this that suggests anything wrong or incomplete about physics; no need for any dualism or magic realm. In a lot of ways this is simply the sceptical case approached more cautiously and from a different angle. It does leave us with some mystery though: what is it for something to be particular; what is the nature of particularity? We’ve already said we can’t describe it effectively or reduce it theoretically, but surely there must be something we can do to apprehend it better? This is the problem of reality…

[Many thanks to Sergio for the kind review here. Many thanks also to the generous people who have given me good reviews on amazon.com; much appreciated!]

boy blueAntti Revonsuo has a two-headed paper in the latest JCS; at least it seems two-headed to me – he argues for two conclusions that seem to be only loosely related; both are to do with the Hard Problem, the question of how to explain the subjective aspect of experience.

The first is a view about possible solutions to the Hard Problem, and how it is situated strategically. Revonsuo concludes, basically, that the problem really is hard, which obviously comes as no great surprise in itself. His case is that the question of consciousness is properly a question for cognitive neuroscience, and that equally cognitive neuroscience has already committed itself to owning the problem: but at present no path from neural mechanisms up to conscious experience seems at all viable. A good deal of work has been done on the neural correlates of consciousness, but even if they could be fully straightened out it remains largely unclear how they are to furnish any kind of explanation of subjective experience.

The gist of that is probably right, but some of the details seem open to challenge. It’s not at all clear to me that consciousness is owned by cognitive neuroscience; rather, the usual view is that it’s an intensely inter-disciplinary problem; indeed, that may well be part of the reason it’s so duffucult to get anywhere. Second, it’s not at all that clear how strongly committed cognitive neuroscience is to the Hard Problem. Consciousness, fair enough; consciousness is indeed irretrievably one of the areas addressed by cognitive neuroscience. But consciousness is a many-splendoured thing, and I think cognitive neuroscientists still have the option of ignoring or being sceptical about some of the fancier varieties, especially certain conceptions of the phenomenal experience which is the subject of the Hard Problem. It seems reasonable enough that you might study consciousness in the Easy Problem sense – the state of being conscious rather than unconscious, we might say – without being committed to a belief in ineffable qualia – let alone to providing a neurological explanation of them.

The second conclusion is about extended consciousness; theories that suggest conscious states are not simply states of the brain, but are partly made up of elements beyond our skull and our skin. These theories too, it seems, are not going to give us a quick answer in Revonsuo’s opinion – or perhaps any answer. Revonsuo invokes the counter example of dreams. During dreams, we appear to be having conscious experiences; yet the difference between a dream state and an unconscious state may be confined to the brain; in every other respect our physical situation may be identical. This looks like strong evidence that consciousness is attributable to brain states alone.

Once, Revonsuo acknowledges, it was possible to doubt whether dreams were really experiences; it could have been that they were false memories generated only at the moment of awakening; but he holds that research over recent years has eliminated this possibility, establishing that dreams happen over time, more or less as they seem to.

The use of dreams in this context is not a new tactic, and Revonsuo quotes Alva Noë’s counter-argument, which consists of three claims intended to undermine the relevance of dreams; first, dream experiences are less rich and stable than normal conscious experiences; second, dream seeing is not real seeing; and third, all dream experiences depend on prior real experiences. Revonsuo more or less gives a flat denial of the first, suggesting that the evidence is thin to non-existent:  Noë just hasn’t cited enough evidence. He thinks the second counter-argument just presupposes that experiences without external content are not real experiences, which is question-begging. Just because I’m seeing a dreamed object, does that mean I’m not really seeing? On the third point he has two counter arguments. Even if all dreams recall earlier waking experiences, they are still live experiences in themselves; they’re not just empty recall – but in any case, that isn’t true; people who are congenitally paraplegic have dreams of walking, for example.

I think Revonsuo is basically right, but I’m not sure he has absolutely vanquished the extended mind. For his dream argument to be a real clincher, the brain state of dreaming of seeing a sheep and the brain state of actually seeing a sheep have to be completely identical, or rather, potentially identical. This is quite a strong claim to make, and whatever the state of the academic evidence, I’m not sure how well it stands up to introspective examination. We know that we often take dreams to be real when we are having them, and in fact do not always or even generally realise that a dream is a dream: but looking back on it, isn’t there a difference of quality between dream states and waking states? I’m strongly tempted to think that while seeing a sheep is just seeing a sheep, the corresponding dream is about seeing a sheep, a little like seeing a film, one level higher in abstraction. But perhaps that’s just my dreams?

knight 2This is the second of four posts about key ideas from my book The Shadow of Consciousness. This one looks at how the brain points at things, and how that could provide a basis for handling intentionality, meaning and relevance.

Intentionality is the quality of being about things, possessed by our thoughts, desires, beliefs and (clue’s in the name) our intentions. In a slightly different way intentionality is also a property of books, symbols, signs and, pointers. There are many theories out there about how it works; most, in my view, have some appeal, but none looks like the full story.

Several of the existing theories touch on a handy notion of natural meaning proposed by H.P.Grice. Natural meaning is essentially just the noticeable implication of things. Those spots mean measles; those massed dark clouds mean rain. If we regard this kind of ‘meaning’ as the wild, undeveloped form of intentionality we might be able to go on to suggest how the full-blown kind might be built out of it; how we get to non-natural meaning, the kind we generally use to communicate with and the kind most important to consciousness.

My proposal is that we regard natural meaning as a kind of pointing, and that pointing, in turn, is the recognition of a higher-level entity that links the pointer with the target. Seeing dark clouds and feeling raindrops on your head are two parts of the recognisable over-arching entity of a rain-storm. Spots are just part of the larger entity of measles. So our basic ability to deal with meanings is simply a consequence of our ability to recognise things at different levels.

Looking at it that way, it’s easy enough to see how we could build derived intentionality, the sort that words and symbols have; the difference is just that the higher-level entities we need to link everything up are artificial, supplied by convention or shared understanding: the words of a language, the conventions of a map. Clouds and water on my head are linked by the natural phenomenon of rain: the word ‘rain’ and water on my head are linked by the prodigious vocabulary table of the language. We can imagine how such conventions might grow up through something akin to a game of charades; I use a truncated version of a digging gesture to invite my neighbour to help with a hole: he gets it because he recognises that my hand movements could be part of the larger entity of digging. After a while the grunt I usually do at the same time becomes enough to convey the notion of digging.

External communication is useful, but this faculty of recognising wholes for parts and parts for wholes enables me to support more ambitious cognitive processes too, and make a bid for the original (aka ‘intrinsic’) intentionality that characterises my own thoughts, desires and beliefs. I start off with simple behaviour patterns in which recognising an object stimulates the appropriate behaviour; now I can put together much more complex stuff. I recognise an apple; but instead of just eating it, I recognise the higher entity of an apple tree; from there I recognise the long cycle of tree growth, then the early part in which a seed hits the ground; and from there I recognise that the apple in my hand could yield the pips required, which are recognisably part of a planting operation I could undertake myself…

So I am able to respond, not just to immediate stimuli, but to think about future apples that don’t even exist yet and shape my behaviour towards them. Plans that come out of this kind of process can properly be called intentional (I thought about what I was doing) and the fact that they seem to start with my thoughts, not simply with external stimuli, is what justifies our sense of responsibility and free will. In my example there’s still an external apple that starts the chain of thought, but I could have been ruminating for hours and the actions that result might have no simple relationship to any recent external stimulus.

We can move thinks up another notch if I begin, as it were, to grunt internally. From the digging grunt and similar easy starts, I can put together a reasonable kind of language which not only works on my friends, but on me if I silently recognise the digging grunt and use it to pose to myself the concept of excavation.

There’s more. In effect, when I think, I am moving through the forest of hierarchical relationships subserved by recognition. This forest has an interesting property. Although it is disorderly and extremely complex, it automatically arranges things so that things I perceive as connected in any way are indeed linked. This means it serves me as a kind of relevance space, where the things I may need to think about are naturally grouped and linked. This helps explain how the human brain is so good at dealing with the inexhaustible: it naturally (not infallibly) tends to keep the most salient things close.

In the end then, human style thought and human style consciousness (or at any rate the Easy Problem kind) seem to be a large and remarkably effective re-purposing of our basic faculty of recognition. By moving from parts to whole to other parts and then to other wholes, I can move through a conceptual space in a uniquely detached but effective way.

That’s a very compressed version of thoughts that probably need a more gentle introduction, but I hope it makes some sense. On to haecceity!

 

all overAn interesting study at Vanderbilt University (something not quite right about the brain picture on that page) suggests that consciousness is not narrowly localised within small regions of the cortex, but occurs when lots of connections to all regions are active. This is potentially of considerable significance, but some caution is appropriate.

The experiment asked subjects to report whether they could see a disc that flashed up only briefly, and how certain they were about it. Then it compared scans from occasions when awareness of the disc was clearly present or absent. The initial results provided the same kind of pattern we’ve become used to, in which small regions became active when awareness was present. Hypothetically these might be regions particularly devoted to disc detection; other studies in the past have found patterns and regions that appeared to be specific for individual objects, or even the faces of particular people.

Then, however, the team went on to assess connectedness, and found that awareness was associated with many connections to all parts of the cortex. This might be taken to mean that while particular small bits of brain may have to do with particular things in the world, awareness itself is something the whole cortex does. This would be a very interesting result, congenial to some, and it would certainly affect the way we think about consciousness and its relation to the brain.

However, we shouldn’t get too carried away too quickly.  To begin with, the study was about awareness of a flashing disc; a legitimate example of a conscious state, but not a particularly complex one and not necessarily typical of distinctively human types of higher-level conscious activity. Second, I’m not remotely competent to make any technical judgement about the methods used to assess what connections were in place, but I’d guess there’s a chance other teams in the field might have some criticisms.

Third, there seems to be scope for other interpretations of the results. At best we know that moments of disc awareness were correlated with moments of high connectedness. That might mean the connectedness caused or constituted the awareness, but it might also mean that it was just something that happens at the same time. Perhaps those narrow regions are still doing the real work: after all, when there’s a key political debate the rest of the country connects up with it; but the debate still happens in a single chamber and would happen just the same if the wider connectivity failed. It might be that awareness gives a wide selection of other regions a chance to chip in, or to be activated in turn, but that that is not an essential feature of the experience of the disc.

For some people, the idea of consciousness bring radically decentralised will be unpalatable. To them, it’s a functional matter which more or less has to happen in a defined area. OK, that area could be stretched out, but the idea that merely linking up disparate parts of the cortex could in itself bring about a conscious state will seem too unlikely to be taken seriously. For others, who think the brain itself is too narrow an area to fully contain consciousness, the results will hardly seem to go far enough.

For myself, I feel some sympathy with the view expressed by Margaret Boden in this interview, where she speaks disparagingly of current neuroscience being mere ‘natural history’ – we just don’t have enough of a theory yet to know what we’re looking at. We’re still in the stage where we’re merely collecting facts, findings that will one day fit neatly into a proper theoretical framework, but at the moment don’t really prove or disprove any general hypotheses. To put it another way, we’re still collecting pieces of the jigsaw puzzle but we don’t have any idea what the picture is. When we spot that, then perhaps the pieces will all… connect.