Tag Archives: qualia

Qualia: The Movie

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Picture: ghost. I suppose the zombies couldn’t have the film industry all to themselves for ever, and here it is: Qualia, the movie (via). I wondered at first whether this was something to do with Sony and their Qualia man Ken Mogi, but in fact it seems it is a small independent venture. I said ‘here it is’, but actually all we have for the moment is a trailer: it seems that the funds required (amounts which I expect wouldn’t cover one day’s catering budget on a Hollywood blockbuster) have been difficult to get together.

How do you make a film about qualia? (Ken Mogi would probably ask how you could make one without them.) I can’t quite decide whether getting ineffable qualities into a film is an amusingly quixotic endeavour or an admirable ambition. It seems all too likely that you would end up with either the talkiest, chin-strokingest film ever made; or an exciting dramatisation of the life of Mary the Colour Scientist. (Susan Blackmore suggested that students should act out this famous gedankenexperiment, after all, though how that would help still rather eludes me.) Actually there’s no reason why a film can’t at least raise genuine philosophical issues. I’ll always remember the Captain’s advice on how to deal with the malfunctioning bomb in Dark Star (“Teach it phenomenology”), and The Matrix is often credited with asking interesting questions – though sadly the red and blue pills were soon put aside so that the film could become a kung fu movie performed by people dressed as a Eurythmics tribute band (The Revenge Tourists?).

I haven’t found much information about the actual plot of Qualia, but it seems it has something to do with research which triggers or examines ghostly occurrences and disturbs someone’s complacent monist materialism. Nothing wrong with disturbing our dogmatic slumbers, of course. I like to think that at some stage a grave scientist will say “Sir! We’re detecting… phenomena.”

But the association with ghosts is not particularly welcome. I wonder whether this is another sign, like the use of qualia to buttress the theist case, that the hard problem potentially appeals to those who would like the world to be less scientific and more magical.  I hope not: I’d hate to see New Age shops selling qualia-enhancing crystals. Perhaps that’s just snobbery?  After all It’s legitimate to claim qualia as evidence for some kind of dualism, and some kind of dualism is what you might well be looking for if you wanted to provide ghosts with some respectable ontological underpinnings. Still, I can only look forward to the film with qualified enthusiasm .

Signatures of Consciousness

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Picture: Stanislas Dehaene. Edge has an interesting talk by Stanislas Dehaene.  He and his team, using a range of tools, have identified ‘signatures’ of awareness; marked changes in activity in certain brain regions which accompany awareness of a particular stimulus. They made a clever use of the phenomenon of ‘masking’, in which the perception of a word can be obliterated if it follows too rapidly after the presentation of an earlier one. By adjusting the relevant delay, the team could compare the effect of a stimulus which never reached consciousness with one that did. Using this and similar techniques they identified a number of clear indications of conscious awareness: increased activity in the early stages of processing and activity in new regions, including the prefrontal cortex and inferior parietal. It appears that this is accompanied by a ‘P3 wave’ which is quite easy to detect even with nothing more sophisticated than electrodes on the scalp. Interestingly it seems that the difference between a stimulus which does not make it into consciousness and one which does emerges quite late, after as much as a quarter of a second of processing.

No-one, I suspect, is going to be amazed by the news that conscious awareness is accompanied by distinctive patterns of brain activity; but identifying the actual ‘signatures’ has direct clinical relevance in cases of coma and apparent persistent vegetative state. In principle Dehaene’s research should allow conscious reactions continuing in a paralysed patient to be identified; this possibility is being actively pursued.

More speculative and perhaps of deeper theoretical interest, Dehaene puts forward a theory of consciousness as a global neuronal workspace, another variation on the global workspace theory of Bernard Baars (an idea which keeps being picked up by others, which must suggest that it has something going for it). Dehaene offers the view that a particular function of the workspace is to allow inputs to hang around for an extended period instead of dissipating. Among other benefits, this allows the construction of chains of processing operations, something Dehaene likens to a Turing machine, though it sounds a little messier than that to me. Further ingenious experiments have lent support to this idea; the researchers were able to contrast subjects’ chaining ability when information was supplied subliminally or consciously (this may sound odd, but subjects can perform at better-than-chance levels even with subliminal stimuli).

Dehaene says that he is dealing only with one variety of consciousness – in the main it’s awareness, which in some respects is the basement level compared to the more high-flown self-reflective versions. But in passing the talk does clarify a question which has sometimes troubled me in the past about global workspace theories – why should they involve consciousness at all? It seems easy to understand that the brain might benefit from a kind of clearing house where information from different sources is shared – but couldn’t that happen, as it were, in the dark? What does the magic ingredient of consciousness add to the process?

Well, being in the global workspace means being accessible to several different systems (no intention here to commit to any particular view about modularity); and one of those systems is the vocal reporting system. So as a natural consequence of being in the workspace, inputs become things we can vocally report, things we can talk about. Things we can talk about are surely objects of consciousness in some quite high-level sense.

Dehaene does not go down this path, but I wondered how far we could take it; is there a plausible explanation of phenomenal consciousness in terms of a global workspace? If we followed the same pattern of argument we used above, we would be looking to say that conscious experiences acquired qualia because being in the workspace made them available to the qualic system, whatever that might be. I think some people, those who tend to want to reduce qualia to flags or badges that give inputs a special weight, might find this kind of perspective congenial, but it doesn’t appeal all that much to me. I would prefer an argument that related the appearance of qualia to a sensory input’s being available to a global collection of sensory and other systems; something to do with resonances across modalities; but I happily confess I have no clear idea of how or exactly why that would work either.

The Ego Tunnel (pt 1)

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Picture: Metzinger. The denial of one’s own existence might seem a desperate philosophical strategy, but denying the reality of the self is a line which a number of people have taken, and Thomas Metzinger is prominent among them. The thesis of his massive 2003 work is summed up in the title: Being No One: The Self-Model Theory of Subjectivity. In that book, Metzinger made a commendable effort to balance philosophy and science; but the sheer size of the resulting text may have deterred some readers – I confess to being somewhat daunted myself. Now he has come back with a slimmer volume The Ego Tunnel which is aimed at a wider public and raises wider issues which Metzinger suggests need public attention.

Metzinger’s theory – the Self-model Theory of Subjectivity or SMT – suggests that subjective experience is really a kind of trick the brain plays on itself. Our brain sets up a model of the world (actually based on fairly limited data) to which it then adds a model of us, ourselves. The coherence of the model and the fact that the processes supporting it are transparent – ie invisible to us – yield the vivid impression of a self in direct contact with reality, and that’s where subjectivity arises; although in fact the whole thing is simply an illusion.

Metzinger’s view of qualia is characteristically complex. He has a good argument against the existence of what he calls canonical qualia, qualia conceived as subjective universals. He points out that our ability to discriminate is far greater than our ability to recognise. So, if we are presented with examples of green 64 and green 66, we can readily tell the difference: but if at a later stage we are presented with one of the examples, we have no hope of telling which it is. So there is no single thing that consistently goes along with the experience of green 64.
Concluding that at any rate we need to distinguish between ‘qualia’ available to memory and qualia available to the faculty of recognition, Metzinger goes on to distinguish a series of possible conceptions of qualia, ending with ‘Metzinger qualia’ which are available attentionally but not cognitively. These are slippery customers for obvious reasons, impossible to report and broadly ineffable – but then that’s how qualia are generally assumed to be.

Even as a summary, the foregoing is a bare and radically, probably over- simplified view of the theory, however. Metzinger actually presents ten constraints which need to be satisfied for the occurrence of subjective experience: they are:

  • Globality; as in ‘global workspace’; conscious items are always integrated into an overall world-model,
  • Presentationality; present in the now , temporal immediacy,
  • Convolved holism; objects of experience are made up of collections of other objects in a nested hierarchy,
  • Dynamicity; the perceived world flows through constant changes,
  • Perspectivalness; we experience the world from a point of view,
  • Transparency; we cannot see the works – the neural processing which gives rise to our experience is excluded from conscious experience,
  • Offline activation; subjective experience is not confined to the live inputs from our senses, a notable exception being dreams, where a whole non-existent world appears.
  • Representation of intensities; besides distinguishing between qualia (whichever version we’re dealing with) we can distinguish their levels of intensity,
  • Homogeneity; areas of pink, for example, are made up of smaller areas of pink, not red and white at once, and
  • Adaptivity; the features of subjective experience have to be things that could reasonably have appeared in the course of evolution.

You may feel that there’s something a bit odd about this list, especially the appearance of ‘adaptivity’. One does not have to be a creationist to feel uneasy about the idea that that is really an essential feature of conscious experience in any deep sense. In a précis which he prepared for a discussion on the Psyche site – sadly this no longer appears to be available – Metzinger discussed only the first six constraints, which suggests that the last four are at least somewhat dispensable. This is a bit confusing – is homogeneity essential to conscious experience, or was that just a kind of bonus, a description of a property of phenomenal experience which is important but not a defining requirement? I think one issue here may be that Metzinger seems to want to do two jobs at once; he wants to explain subjectivity in a philosophical sense, but he also wants to describe and categorise phenomenal experience in a way which can be related to scientific observation, clarifying the puzzling phenomenology of blindsight and other unusual conditions. These are not incompatible aims, exactly, and there’s no absolute reason why one account couldn’t do both, but there is a tension. A robust philosophical explanation would pare down the account to its essentials, while the description of subjectivity seems to be something we would want to do as fully as possible.

So Metzinger, for example, notes that convolution is one property of phenomenal experience and homogeneity is another. If we’re looking for one kind of explanation, to be told that subjective experience breaks down into things which are different, and also that subjective experience sometimes breaks down into things that are the same, is not very helpful; but as a description of different ways phenomenology can work it’s a legitimate clarification.

In the new book, Metzinger boils the requirement down in terms which make it easier for us to get to grips with the theory in ways that relate to our usual concerns here, by asking what it would take to build an Ego Machine, an artificial conscious subject.

The recipe requires us to begin with an integrated and dynamical world-model . We must then ensure that the information flow is organised so as to assign events to a present moment, a Now; and that the images presented by the model are transparent: again, we must not be able to see the works. If these constraints are satisfied, a world appears. The last step is to add to the model an equally transparent representation of an experiencing self; then the artificial entity will finally appear to itself to be someone, and to be there. There will seem to be someone in the Ego Tunnel, Metzinger’s equivalent of Plato’s cave.

This seems to me to make quite a lot of sense, but the reader’s verdict is likely to be determined by whether it ‘feels right’ – does it finally dispel that sense of mystery? It must be taken into account that Metzinger’s theory itself provides strong reasons why his conclusions are going to seem intuitively unacceptable, so a kind of mental ‘aiming off’ may be required. I think we have to ask ourselves two questions. The first is: can we imagine that all of Metzinger’s requirements could be met in the absence of ‘inner experience’: does it seem that we could have his kind of world-model running with a representation of a self in it and yet still be, as it were, only a Metzinger zombie?

If we’re happy that this is not a possibility, there still remains the question of whether Metzinger has smuggled his consciousness into the tunnel. Do any of his constraints covertly imply that consciousness is already present?

I think some of them could – presentationality? Perspectivalness? – but carefully read, I don’t think they need do. Whether some of their intuitive appeal derives from the reader having unconsciously done some illicit importation is, I suppose, a matter for the reader. Some of the constraints do look a bit strange in other ways. Let’s consider that requirement of transparency, for example. In the ego tunnel, data about the outside world must be globally available, but there must be no information about how this data got to the tunnel, since that would dispel the illusion that what we are dealing with is the real world itself. But why would there be? A TV screen does not automatically contain an account of how the TV itself or the local transmitter works. Metzinger has an odd perspective here which seems to start with the idea that the mind naturally knows everything and has to be carefully shielded. In The Ego Tunnel he talks about our sensory apparatus filtering out most of the potential information about the world, limiting us to a meagre trickle, as though our natural state was a kind of omniscience which is only reined in by the limitations of our eyes. Isn’t it the other way round?

Look at it the other way: suppose we were consciously aware of the fact that light rays were being processed by our retinas, would that destroy our sense of ourselves as existing in the world? Actually, I doubt it. The fact that we can see the edges of the screen does not inhibit us much from getting immersed in a film: for that matter the very visible appearance of the book does not prevent our getting immersed in a novel. Similarly, the fact that I can see a ‘floater’ in my right eye at the moment doesn’t cause reality to recede from me although it is a tell-tale sign of the visual processes that intervene between my brain and the world.

But there’s more in the Ego Tunnel…

(My apologies if things have been a bit slow here – I rashly committed to Nanowrimo this year so a lot of my energy is going to turning out a 50,000 word novel text this month. You can read the results here.  – Peter)

Bafflement

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Picture: Avshalom C. Elitzur. Over at Robots.net, they’ve noticed a bit of a resurgence of dualism recently, and it seems that Avshalom C. Elitzur is in the vanguard, with this paper presenting an argument from bafflement.

The first part of the paper provides a nice, gentle introduction to the issue of qualia in dialogue form. Elitzur explains the bind that we’re in in this respect: we seem to have an undeniable first-hand experience of qualia, yet they don’t fit into the normal physical account of the world. We seem to be faced with a dilemma: either reject qualia – perhaps we just misperceive our percepts as qualia – or accept some violation of normal physics. The position is baffling: but Elitzur wants to suggest that that very bafflement provides a clue.  His strategy is to try to drag the issue into the realm of science, and the argument goes like this:

1. By physicalism, consciousness and brain processes are identical.
2. Whence, then, the dualistic bafflement about their apparent nonidentity?
3. By physicalism, this nonidentity, and hence the resultant bafflement, must be due to error.
4. But then, again by physicalism, an error must have a causal explanation.
5. Logic, cognitive science and AI are advanced enough nowadays to provide such an explanation for the alleged error underlying dualism, and future neurophysiology must be able to point out its neural correlate.

That last point seems optimistic. Cognitive science may be advanced enough to provide explanations for a number of cognitive deficits and illusions, but sometimes only partial ones; and not all errors are the result of a structural problem. It’s particularly optimistic to think that all errors must have an identifiable neural correlate. But this seems to be what Elitzur believes. He actually says

“When future neurophysiology becomes advanced enough to point out the neural correlates of false beliefs, a specific correlate of this kind would be found to underlie the bafflement about qualia.”

The neural correlates of false beliefs? Crikey! It’s perfectly reasonable to assume that all false beliefs have neural correlates – because one assumes that all beliefs do – but the idea that false ones can be distinguished by their neural properties is surely evidently wrong. An argument hardly seems required, but it’s easy, for example, to picture a man who believes a coin has come down heads. If it has, his belief is true, but if it’s actually tails, exactly the same belief, with identical neural patterns would be false. I think Elitzur must mean something less startling than what he seems to be saying; he must, I think, take it as read that if qualia are a delusion, they would be a product of some twist or quirk in our mental set-up. That’s not an unreasonable position, one that would be shared by Metzinger, for example (discussion coming soon).

As it happens, Elitzur doesn’t think qualia are delusions; instead he has an argument which he thinks shows that interactionist dualism – a position he doesn’t otherwise find very attractive – must be true. The argument is to do with  zombies.  Zombies in this context, as regular readers will know, are people who have all the qualities normal people posess, except qualia. Because qualia have no physical causal effects,  the behaviour of zombies, caused by normal physical factors, is exactly like that of normal people. Elitzur quotes Chalmers explaining that zombie-Chalmers even talks about qualia and writes philosophical papers about them, though in fact he has none. The core of Elitzur’s position is his incredulity over this conclusion. How could zombies who don’t have qualia come to be worried about them?

It is an uncomfortable position, but if we accept that zombies are possible and qualia exist, Chalmers’ logic seems irrefutable.  Ex hypothesi, zombies follow the same physical laws as us:  it’s ultimately physics that causes the movements of our hands and mouths involved in writing or speaking about qualia: so our zombie counterparts must go through the same motions, writing the same books and emitting the same sounds. Since this seems totally illogical to Elitzur, he offers the rationalisation that when zombies talk about qualia, they must in fact merely be talking about their percepts. But this asymmetry provides a chink which can be used to prose zombies and qualiate people apart. If we ask Chalmers whether his zombie equivalent is possible, he replies that it is; but, suggests Elitzur, if we ask zombie Chalmers (whom he call ‘Charmless’) the same question, he replies in the negative.  Chalmers can imagine himself functioning without qualia, because qualia have no functional role: but Charmless cannot imagine himself functioning without percepts, because percepts are part of the essence of his sensory system. (It is possible to take the analogous view about qualia of course – namely that zombies are impossible, because a physically identical person just would necessarily have the same qualia). So zombies differ from us, oddly enough, in not being able to conceive of their own zombies.

For Elitzur, the conclusion is inescapable; qualia do have an effect on our brains. He chooses therefore to bite the bullet of accepting that the laws of physics must be messed up in some way – that where qualia intervene, conservation laws are breached, unpalatable as this conclusion is. One consoling feature is that if qualia do have physical effects, they can be included in the evolutionary story; perhaps they serve to hasten or intensify our responses: but overall it’s regrettable that dualism turns out to be the answer.

I don’t think this is a convincing conclusion; it seems as if Elitzur’s incredulity has led him into not taking the premises of the zombie question seriously enough. It just is the case ex hypothesi that all of our zombies’ behaviour is caused by the same physical factors as our own behaviour; it follows that if their talk about qualia is not caused by qualia, neither is ours (note that this doesn’t have to mean that either we or the zombies fail to talk about qualia). There are other ways out of this uncomfortable position, discussed by Chalmers (perhaps, for example, our words about qualia are over-determined, caused both by physical factors and by our actual experiences). My own preferred view is that whatever qualia might be, they certainly go along with certain physical brain functions, and that therefore any physical duplicate of ourselves would have the same qualia; that zombies, in other words, are not possible. It’s just a coincidence, I’m sure, that in Elitzur’s theory this is the kind of thing a zombie would say…

Clockwork Orange syndrome?

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Picture: Clockwork Orange. Over at the Institute for Ethics and Emerging Technologies,  Martine Rothblatt offers to solve the Hard Problem for us in her piece “Can Consciousness be created in Software?”.  The Hard Problem, as regulars here will know, is how to explain subjective experience, the redness of red, the ineffable inner sense of what experience is like. Rothblatt’s account is quite short, and on my first reading I had slipped past the crucial sentences and discovered she was claiming victory before I quite realised what her answer was, so that I had to go back and read it again more carefully.

She says: “Redness is part of the gestalt impression obtained in a second or less from the immense pattern of neural connections we have built up about red things… With each neuron able to make as many as 10,000 connections, and with 100 billion neurons, there is ample possibility for each person to have subjective experiences through idiosyncratic patterns of connectivity. “ The point seems to be that the huge connectivity of the human brain makes it easy for everyone’s experience of redness to be unique.

This is an interesting and rather novel point of view. One traditional way of framing the Hard Problem is to ask whether the blue that I see is really the same as the blue that you see – or could it be equivalent to my orange? How would we know?  On Rothblatt’s view it would seem the answer must be that my blue is definitely not the same as yours, nor the same as anyone else’s; and nor is it the same as your orange, or Fred’s green for that matter, everyone having an experience of blue which is unique to them and their particular pattern of neuronal connection. I find this a slightly scary perspective, but not illogical. Presumably from Rothblatt’s point of view the only thing the different experiences have in common is that they all refer to the same blue things in the real world (or something like that).

Is it necessarily so, though?  Does the fact that our neuronal connections are different mean our experiences are different? I don’t think so. After all, I can write a particular sentence in different fonts and different sizes and colours of text;  I can model it in clay or project it on a screen, yet it remains exactly the same sentence. Differences in the substrate don’t matter.  We can go a step further: when people think of that same sentence, we must presume that the neuronal connections supporting the thought are different in each individual – yet it’s the same sentence they’re thinking. So why can’t different sets of neural connections support the same experience of blue in different heads?

Rothblatt’s account is a brief one, and perhaps she has some further theoretical points which explain the relationship between neuronal structures and subjective experiences in a way which would illuminate this. But hang on – wasn’t the relationship between neuronal structures and subjective experience the original problem? Slapping our foreheads, we realise that Rothblatt has palmed off on us an idea about uniqueness which actually doesn’t address the Hard Problem at all. The Hard Problem is not about how brains can accommodate a million unique experiences: it’s about how brains can accommodate subjectivity, how they make it true that there is something it is like to see red.

I fear this may be another example of the noticeable tendency of some theorists, especially those with a strong scientific background, to give us clockwork oranges, to borrow the metaphor Anthony Burgess used in a slightly different context: accounts that model some of the physical features quite nicely (see, it’s round, it hangs from trees effectively) while missing the essential juice which is really the whole point. According to Burgess, or at least to F. Alexander, the ill-fated character who expresses this view in the novel,  the point of a man is not orderly compliance with social requirements but, as it were, his juice, his inner reality.  I think the answer to the Hard Problem is indeed something to do with our reality (I should say that I mean ‘reality’ in a perfectly everyday sense:  Rothblatt, like some purveyors of mechanical fruit, is a little too quick to dismiss anything not strictly reducible to physics as mysticism) : we’re fine when we’re dealing with abstractions, it’s the concrete and particular which remains stubbornly inexplicable in any but superficial terms.  It’s my real experience of redness that causes the difficulty. Perhaps Rothblatt’s ideas about uniqueness are an attempt to capture the one-off quality of that experience; but uniqueness isn’t quite the point, and I think we need something deeper.

Abilities don’t matter

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Picture: bike. Sam Coleman returned in a recent paper (JCS vol 16, n0 2-3) to the old perennial of Mary the colour scientist.  As you may know, Frank Jackson’s story about Mary was intended to establish that there was something important – qualia – which the simple physical account of the world omitted. Mary, we’re told, knows everything that could possibly be known about colour from a scientific point of view (far more than any living scientist knows, or could know).  She knows all the physical facts. But she has never experienced colour; when she sees a red rose for the first time, doesn’t she learn something new – ie what red looks like? If you agree, then, it is argued, you must agree that there are things in heaven and earth not dreamt of in physicalist philosophy.

One standard riposte to this line of argument is to deny that Mary learns any new facts when she sees red for the first time:  instead, she merely acquires a new ability. Now she can recognise red, when she couldn’t do before; but she doesn’t actually know any new facts about redness or the human optical system. (After all, the phrase ‘she knows what red is like’ literally suggests that she can give a list of things which are like a red object, and say whether the colour of a given object resembles red or not – which sounds a lot like recognition.) We might mention other abilities; the ability to remember or imagine redness, in particular – but none of these involve new knowledge in the ordinary sense, any more than acquiring the ability to ride a bike involves learning new facts. You can read as many books about bicycles as you like: you’ll still fall off the first time you get on one.

Coleman aims to knock this line of argument on the head, not by refuting it but by showing it to be irrelevant. Most attacks on the Ability Hypothesis, he says, address what he calls its inner face directly. They seek to show that what happens to Mary cannot be boiled down to the gaining of an ability – perhaps because all such abilities involve factual knowledge – or they set out to show directly that Mary does indeed learn new facts.  These strategies tend, he says with some justice, to end up mired in a clash of intuitions with no clear way forward.

Instead, then, he concedes that if we wish, we can see what happens to Mary as the acquisition of some new abilities; he addresses instead what he calls the outer face of the problem. What about the analogy of bike-riding? Proponents of the Ability Hypothesis say it does not depend on factual knowledge, and it’s true it doesn’t come from academic book-reading. But what does it involve? Surely it’s all about keeping our balance? That’s a matter of teaching your muscles how to respond quickly and appropriately to certain sensations of tipping over.  So hang on, it actually involves knowledge of what it feels like to wobble – what certain kinds of phenomenal experience are.  Is this kind of knowledge factual knowledge?  Never mind the answer for the moment – all we need do is notice that this is exactly the kind of question we were asking about Mary’s experience of redness in the first place. The Ability Hypothesis has merely taken us back to where we started – so we need not waste our time on it.

A neat piece of footwork, I think, and Coleman’s analysis of the phenomenal element in abilities such as bike-riding, ear-waggling, and the use of chopsticks provides an interesting new insight, worth having in its own right. (Readers may be interested in the Phenomenal Qualities Project, whose three-year mission is due to begin next month; Coleman is co-investigator to Paul Coates and the list of project members includes some stellar names.)

Where are we left with Mary meanwhile, though? Should we now accept the refutation of physicalism she represents? No, I would say, but then again yes.

One thing that’s sure about Mary is that if she does acquire new knowledge, it is knowledge of some special kind. It isn’t the sort we can write down and transmit in words – that much is true ex hypothesi, because if it were that kind of knowledge, it would be among the things Mary already knows. It’s tempting to denounce this kind of knowledge as metaphorical or worse, but let’s merely ask whether it’s fair to expect the theory of physicalism to include it.  Theories, after all, are expressed in words, and typically written down; if we’re dealing with facts that can’t be dealt with that way it seems only reasonable to conclude that no theory could deal with them and that they must remain extra-theoretical.  Physicalism might then be incomplete in some sense, but we have no reason to think it isn’t as complete as any theory could be.  How much is it reasonable to ask?

And yet, and yet…  We’re talking here about what things are like;  this somehow still feels like a problem where more could be said after all. We can’t expect that our theories should deliver ineffable reality itself, but doesn’t it seem that there is some tantalising last elucidation obtainable here, if only we knew how to go about it?

Radiotelepathy

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Picture: Freeman Dyson. I see that at Edge they have kept up their annual custom of putting a carefully-chosen question to a group of intellectuals.  This year, they asked “What game-changing scientific ideas and developments do you expect to live to see?”. There were many interesting answers. Freeman Dyson foresaw what he called ‘radiotelepathy‘. The idea is that a set of small implants record the activity of your brain which is then transmitted and delivered into someone else’s (and vice versa). Hey presto, at once your thoughts and feelings are shared.

As the Thinking Meat Project remarked,  this idea opens up a number of questions. Given our particular interests here, the first point that came to mind was that this kind of telepathy would surely resolve at last the vexed question of qualia. How do we know that the red seen by others looks the same as the red seen by us? Perhaps the experience they have when they see red is the experience we have when we see green? Or perhaps (a less-often discussed possibility) their red is a bit like our middle C on a badly-tuned piano? Or perhaps their colour experiences are nothing like any of our experiences; perhaps there are an infinite number of phenomenal experiences which go with the perception of colour, and everyone has their own unique and ineffable set.

Well, with Dyson telepathy, there would be no need for us to wonder any more; just tune in to someone else’s brain, and we can have their experiences ourselves. Or can we? Perhaps not. Even as I write, I can sense hard-liners getting ready to insist that qualia recorded, transmitted, and inserted into a new brain, are not the same as the freshly gathered original ones.  You still wouldn’t know what the real thing was like. It might be that it is our brains themselves that impart the special what-it-is-likeness to experiences, in which case even telepathy won’t help, and we can only ever have our own qualia. I think this exposes the insoluble problem at the heart of the whole qualia issue. Really the only way to know what someone’s experiences are like in themselves, is to be that person. But you can’t be someone else.

But steady on, because it seems highly unlikely to me that Dyson telepathy is feasible. I don’t see any insoluble problem with the hardware he calls for, but downloading brain content is a tricky business, and uploading is even worse. To start with, Dyson talks about the ‘entire brain’, but do we want the whole thing? Do I want the activity of someone else’s cerebellum reproduced in my own? Do I want the control routines for my caridovascular system overwritten? No thanks. So even on the macro scale we have to be very careful about where we put our ingoing signals. Pinpointing the right neurons seems a hopeless task. It’s true that by and large the same regions of the cortex appear to deal with the same functions in different individuals, although variation is also quite possible. It’s also true that recent research has identified individual neurons with very specific responses – neurons that fire, say, in response to the sight of Freeman Dyson, but not in response to anyone else. But so far as I know, it hasn’t been demonstrated that the Dyson neuron in everyone is in the same place even approximately; it actually seems most unlikely, given that brains are wired in highly individual ways, and that indeed, most people have never had the pleasure of meeting Freeman Dyson. I don’t think it’s even been shown that the very same neuron which responds to Dyson today continues to do so next week.  Because all our machines are made to have their states encoded in a readable way, we tend to expect the same of nature, but evolution has no need of legible code.  So it’s very likely that the neural activity which in my brain corresponds to thinking of Freeman Dyson would, when transposed to another cranium,  come out as the tantalising memory of the taste of a biscuit, or an intimation of mortality, or reservations about bicameralism.

Of course it’s worse than that.  Our brains are carefully organised, and the random dumping of alien activity would be oustandingly likely to mess things up.  Would the brain activity that was there before – my own mental activity – be wiped out, so that instead of sharing someone else’s thoughts, I suddenly thought I was someone else? Or could it somehow be merged? Dissolving the barriers and merging with another person can sound almost sensuously appealing (given the right person), but the sudden appearance of unforeshadowed alien thoughts might actually be terrifying, severely disorienting: a threat to the integrity of the psyche liable to end in trauma. In this respect, it’s worth noting that nothing is more disruptive to one signal than another similar signal. If you write a sentence on a piece of paper and then cross it out with two or three lines, it remains easily legible. But if you write even one other sentence over the top of it, it becomes pretty much illegible at once. In the same way, it seems likely that activity from another brain would be the most dirsuptive thing you could input to your own, far worse than random noise.

I think the best alternative would be to home in on sensory inputs in the brain and try to place your interface somewhere early in the system before those inputs reach the more complex functions of consciousness. The result then would be more like hearing an external voice, or seeing an external hallucination. Much easier to deal with, but of course not so extraordinary – not really different in kind from using a video phone. At the end of the day, perhaps it’s best to stick to the brain inputs provided by the designer – our normal senses.  Walter Freeman memorably lamented the cognitive isolation in which we are all ultimately confined; but perhaps that isolation is the precondition of personal identity.