NCCsThis editorial piece notes that we still haven’t nailed down the neural correlates of consciousness (NCCs). It’s part of a Research Topic collection on the subject, and it mentions three candidates featured in the papers which have been well-favoured but now – arguably at any rate – seem to have been found wanting. This old but still useful paper by David Chalmers lists several more of the old contenders. Though naturally a little downbeat, the editorial piece addresses some of the problems and recommends a fresh assault. However, if we haven’t succeeded after twenty-five or thirty years of trying, perhaps common sense suggests that there might be something fundamentally wrong with the project?

There must be neural correlates of consciousness, though, mustn’t there? Unless we’re dualists, and perhaps even if we are, it seems hard to imagine that mental events are not matched by events in the brain. We have by now a wealth of evidence that stimulating parts of the brain can generate conscious experiences artificially, and we’ve always known that damage to the brain damages the mind; sometimes in exquisitely particular ways. So what could be wrong with the basic premise that there are neural correlates of consciousness?

First, consciousness could itself be a mixed bag of different things, not one consistent phenomenon. Conscious states, after all, include such things as being visually aware of a red light; rehearsing a speech mentally; meditating; and waiting for the starting pistol. These things are different in themselves and it’s not particularly likely that their neuronal counterparts will resemble each other.

Then it could be realised in multiple ways. Even if we confine ourselves to one kind of consciousness, there’s no guarantee that the brain always does it the same way. If we assume for the sake of argument that consciousness arises from a neuronal function, then perhaps several different processes will do, just as a bucket, a hose, a fountain and a sewer all serve the function of moving water.

Third, it could well be that consciousness arises, not from any property of the neurons doing the thinking, but from the context they do it in. If the higher order theorists were right, to take one example, for a set of neurons to be conscious would require that another set of neurons was directed at them – so that there was a thought about the thought But whether another set of neurons is executing a function about our first set of neurons is not an observable property of the first set of neurons. As another example it might be that theories of embodiment are true in a strong sense, implying that consciousness depends on context external to the brain altogether.

Fourth, consciousness might depend on finely detailed properties that require very complex decoding. Suppose we have a library and we want to find out which books in it mention libraries; we have to read them to find out. In a somewhat similar way we might have to read the neurons in our brain in detail to find out whether they were supporting consciousness.

Quite apart from these problems of principle, of course, we might reasonably have some reservations about the technology. Even the best scanners have their limitations, typically showing us proxies for the general level of activity in a broad area rather than pinpointing the activity of particular neurons; and it isn’t feasible or ethical to fill a subject’s brain with electrodes. With the equipment we had twenty-five years ago, it was staggeringly ambitious to think we could crack the problem, but even now we might not really be ready.

All that suggests that the whole idea of Neural Correlates of Consciousness is framed in a way which makes it unpromising or completely misconceived. And yet… understanding consciousness, for most people, is really a matter of building a bridge between the physical and the mental; even if we’re not out to reduce the mental to the physical, we want to see, as it were, diplomatic relations established between the two. How could that bridge ever be built without some work on the physical side, and how could that work not be, in part at least, about tracking neuronal activity? If we’re not going to succumb to mystery or magic, we just have to keep looking, don’t we?

I think there are probably two morals to be drawn. The first is that while we have to keep looking for neural correlates of consciousness in some sense (even if we don’t describe the porject that way), it was probably always a little naive to look for the correlates, the single simple things that would infallibly diagnose the presence of consciousness. It was always a bit unlikely, at any rate, that something as simple as oscillating together at 40 Hertz just was consciousness; surely it’s was always going to be a lot more complicated than that?

Second, we probably do need a bit more of a theory, or at least a hypothesis. There’s no need to be unduly narrow-minded about our scientific method; sometimes even random exploration can lead to significant insights just as well as carefully constructed testing of well-defined hypotheses. But the neuronal activity of the brain is often, and quite rightly, described as the most complex phenomenon in the known universe. Without any theoretical insight into how we think neuronal activity might be giving rise to consciousness, we really don’t have much chance of seeing what we’re after unless it just happens by great good fortune to be blindingly obvious. Just having a bit of a look to see if we can spot things that reliably occur when consciousness is present is probably underestimating the task. Indeed, that is sort of the theme of the collection; Beyond the Simple Contrastive Approach. To put it crudely, if you’re looking for something, it helps to have an idea of what the thing you’re looking for looks like.

In another 25 or 30 years, will we still be looking? Or will we have given up in despair? Nil Desperandum!

CamembertCan you change your mind after the deed is done? Ezequiel Di Paolo thinks you can, sometimes. More specifically, he believes that acts can become intentional after they have already been performed. His theory, which seems to imply a kind of time travel, is set out in a paper in the latest JCS.

I think the normal view would be that for an act to be intentional, it must have been caused by a conscious decision on your part. Since causes come before effects, the conscious decision must have happened beforehand, and any thoughts you may have afterwards are irrelevant. There is a blurry borderline over what is conscious, of course; if you were confused or inattentive, if you were ‘on autopilot’ or you were following a hunch or a whim it may not be completely clear how consciously your action was considered.

There can, moreover, be what Di Paolo calls an epistemic change. In such a case the action was always intentional in fact, but you only realise that it was when you think about your own motives more carefully after the event. Perhaps you act in the heat of the moment without reflection; but when you think about it you realise that in fact what you did was in line with your plans and actually caused by them. Although this kind of thing raises a few issues, it is not deeply problematic in the same way as a real change. Di Paolo calls the real change an ontological one; here you definitely did not intend the action beforehand, but it becomes intentional retrospectively.

That seems disastrous on the face of it. If the intentionality of an act can change once, it can presumably change again, so it seems all intentions must become provisional and unreliable; the whole concept of responsibility looks in danger of being undermined. Luckily, Di Paolo believes that changes can only occur in very particular circumstances, and in such a way that only one revision can occur.

His view founds intentions in enactment rather than in linear causation; he has them arising in social interaction. The theory draws on Husserl and Heidegger, but probably the easiest way to get a sense of it is to consider the examples presented by Di Paolo. The first is from De Jaegher and centres, in fittingly continental style, around a cheese board.

De Jaegher is slicing himself a corner of Camembert and notices that his companion is watching in a way which suggests that he too, would like to eat cheese. DJ cuts him a slice and hands it over.
“I could see you wanted some cheese,” he remarks.
“Funny thing, that,” he replies, “actually, I wasn’t wanting cheese until you handed it to me; at that moment the desire crystallised and I now found I had been wanting cheese.”

In a corner of the room, Alice is tired of the party to do; the people are boring and the magnificent cheese board is being monopolised by philosophers enacting around it. She looks across at her husband and happens to scratch her wrist. He comes over.
“Saw you point at your watch,” he says, “yeah, we probably should go now. We’ve got the Stompers’ do to go to.”
Alice now realises that although she didn’t mean to point to her watch originally, she now feels the earlier intention is in place after all – she did mean to suggest they went.

At the Stompers’ there is dancing; the tango! Alice and Bill are really good, and as they dance Bill finds that his moves are being read and interpreted by Alice superbly; she conforms and shapes to match him before he has actually decided what to do; yet she has read him correctly and he realises that after the fact his intentions really were the ones she divined. (I sort of melded the examples.)

You see how it works? No, it doesn’t really convince me either. It is a viable way of looking at things, but it doesn’t compel us to agree that there was a real change of earlier intention. Around the cheese board there may always have been prior hunger, but I don’t see why we’d say the intention existed before accepting the cheese.

It is true, of course, that human beings are very inclined to confabulate, to make up stories about themselves that make their behaviour make sense, even if that involves some retrospective monkeying with the facts. It might well be that social pressure is a particularly potent source of this kind of thing; we adjust our motivations to fit with what the people around us would like to hear. In a loose sense, perhaps we could even say that our public motives have a social existence apart from the private ones lodged in the recesses of our minds; and perhaps those social ones can be adjusted retrospectively because, to put it bluntly, they are really a species of fiction.

Otherwise I don’t see how we can get more than an epistemic change. I’ve just realised that I really kind of feel like some cheese…

Tom StoppardIt was exciting to hear that Tom Stoppard’s new play was going to be called The Hard Problem, although until it opened recently details were scarce. In the event the reviews have not been very good. It could easily have been that the pieces in the mainstream newspapers missed the point in some way; unfortunately, Vaughan Bell of Mind Hacks  didn’t like the way the intellectual issues were handled either (though he had an entertaining evening); and he’s a very sensible and well-informed commentator on consciousness and the mind. So, a disappointing late entry in a distinguished playwright’s record?

I haven’t seen it yet, but I’ve read the script, which in some ways is better for our current purposes. No-one, of course, supposed that Stoppard was going to present a live solution to the Hard Problem: but in the event the play is barely about that problem at all. The Problem’s chief role is to help Hilary, our heroine, get a job at the Krohl Institute for Brain Science, an organisation set up by the wealthy financier Jerry Krohl. Most of the Krohl’s work is on ‘hard’ neuroscience and reductive, materialist projects, but Leo, the head of the department Hilary joins, happens to think the Hard Problem is central. Merely mentioning it is enough to clinch the job, and that’s about it; the chief concern of the rest of the research we’re told about is altruism, and the Prisoner’s Dilemma.

The strange thing is that within philosophy the Hard Problem must be the most fictionalised issue ever. The wealth of thought experiments, elaborate examples and complicated counterfactuals provides enough stories to furnish the complete folklore of a small country. Mary the colour scientist, the zombies, the bats, Twin Earth, chip-head, the qualia that dance and the qualia that fade like Tolkienish elves; as an author you’d want to make something out of all that, wouldn’t you? Or perhaps that assumption just helps explain why I’m not a successful playwright. Of course, you’d only use that stuff if you really wanted to write about the Hard Problem, and Stoppard, it seems, doesn’t really. Perhaps he should just have picked a different title; Every Good Girl Deserves to Know What Became of Her Kid?

Hilary, in fact, had a daughter as a teenager who she gave up for adoption, and who she has worried about ever since. She believes in God because she needs someone effective to pray to about it; and presumably she believes in altruism so someone can be altruistic towards her daughter; though if the sceptic’s arguments are sound, self-interest would work, too.

The debate about altruism is one of those too-well-trodden paths in philosophy; more or less anything you say feels as if it has been in a thousand mouths already. I often feel there’s an element of misunderstanding between those who defend the concept of altruism and those who would reduce it to selfish genery. Yes, the way people behave tends to be consistent with their own survival and reproduction; but that hardly exhausts the topic; we want to know how the actual reasons, emotions, and social conventions work. It’s sort of as though I remarked on how extraordinary it is that a forest pumps so much water way above the ground.

“There’s no pump, Peter,” says BitBucket; “that’s kind of a naive view. See, the tree needs the water in its leaves to survive, so it has evolved as a water-having organism. There are no little hamadryads planning it all out and working tiny pumps. No water magic.”

“But there’s like, capillarity, or something, isn’t there? Um, osmosis? Xylem and phloem? Turgid vacuoles?”

“Sure, but those things are completely explained by the evolutionary imperatives. Saying there are vacuoles doesn’t tell us why there are vacuoles or why they are what they really are.”

“I don’t think osmosis is completely explained by evolution. And surely the biological pumping system is, you know, worth discussing in itself?”

“There’s no pump, Peter!”

Stoppard seems to want to say that greedy reductionism throws out the baby with the bath water. Hilary’s critique of the Prisoner’s Dilemma is that it lacks all context, all the human background that actually informs our behaviour; what’s the relationship of the two prisoners? When the plot puts her into an analogous dilemma, she sacrifices her own interests and career, and is forced to suffer the humiliation of being left with nothing to study but philosophy. In parallel the financial world that pays for the Krohl is going through convulsions because it relied on computational models which were also too reductionist; it turns out that the market thinks and feels and reacts in ways that aren’t determined by rational game theory.

That point is possibly a little undercut by the fact that a reductionist actually foresaw the crash. Amal, who lost out by not rating the Hard Problem high enough, nevertheless manages to fathom the market problem ahead of time…

The market is acting stupid, and the models are out of whack because we don’t know how to build a stupid computer.

But perhaps we are to suppose that he’s learnt his lesson and is ready to talk turgid vacuoles with us sloppy thinkers.

I certainly plan to go and see a performance, and if new light dawns as a result, I’ll let you know.

 

Mr BurnsA real wealth of papers at the OpenMind site, presided over by Thomas Metzinger, including new stuff from Dan Dennett, Ned Block, Paul Churchland, Alva Noë, Andy Clark and many others. Call me perverse, but the one that attracted my attention first is the paper The Neural Organ Explains the Mind by Jakob Hohwy. This expounds the free energy theory put forward by Karl Friston.

The hypothesis here is that we should view the brain as an organ of the body in the same way as we regard the heart or the liver. Those other organs have a distinctive function – in the case of the heart, it pumps blood  –  and what we need to do is recognise what the brain does. The suggestion is that it minimises free energy; that honestly doesn’t mean much to me, but apparently another way of putting it is to say that the brain’s function is to keep the organism within a limited set of states. If the organism is a fish, the brain aims to keep it in the right kind of water, keeps it fed and with adequate oxygen, and so on.

It’s always good to get back to some commonsensical. pragmatic view, and the paper shows that this is a fertile and flexible hypothesis, which yields explanations for various kinds of behaviour. There seem to me to be three prima facie objections. First, this isn’t really  a function akin to the heart pumping blood; at best it’s a high level meta-function. The heart does blood pumping, the lungs do respiration, the gut does digestion; and the brain apparently keeps the organism in  conditions where blood can go on being pumped, there is still breathable air available, food to be digested, and so on. In fact it oversees every other function and in completely novel circumstances it suddenly acquires new functions: if we go hang-gliding, the brain learns to keep us flying straight and level, not something it ever had to do in the earlier history of the human race.  Now of course, if we confront the gut with a substance it never experienced before, it will probably deal with it one way or another; but it will only deploy the chemical functions it always had; it won’t learn new ones. There’s a protean quality about the brain that eludes simple comparisons with other organs.

A second problem is that the hypothesis suggests the brain is all about keeping the organism in  states where it is comfortable, whereas the human brain at least seems to be able to take into account future contingencies and make long-term plans which enable us to abandon the ideal environment of our beds each morning and go out into the cold and rain. There is a theoretical answer to this problem which seems to involve us being able to perceive  things across space and time; probably right, but that seems like a whole new function rather then something that drops out naturally from minimising free energy; I may not have understood this bit correctly. It seems that when we move our hand, it may happen because we have, in contradiction of the evidence, adopted the belief that our hand is already moving; this belief serves to minimise free energy and our belief that the hand is moving causes the actual movement we believe in.

Third and worse, the brain often seems to impel us to do things that are risky, uncomfortable, and damaging, and not necessarily in pursuit of keeping our states in line with comfort, even in the long term. Why do we go hang-gliding, why do we take drugs, climb mountains, enter a monastery or convent? I know there are plenty of answers in terms of self-interest, but it’s much less clear to me that there are answers in terms of minimising free energy.

That’s all very negative, but actually the whole idea overall strikes me as at least a novel and interesting perspective. Hohwy draws some parallels with the theory of evolution; like Darwin’s idea, this is a very general theory with alarmingly large claims, and critics may well say that it’s either over-ambitious or that in the end it explains too much too easily; that it is, ultimately, unfalsifiable.

I wouldn’t go that far; it seems to me that there are a lot of potential issues, but that the theory is very adaptable and productive in potentially useful ways. It might well be a valuable perspective. I’m less sure that it answers the questions we’re really bothered about. Take the analogy of the gut (as the theory encourages us to do). What is the gut’s function? Actually, we could define it several ways (it deals with food, it makes poop, it helps store energy). One might be that the gut keeps the bloodstream in good condition so far as nutrients are concerned, just as the lungs keep it in good condition in respect of oxygenation. But the gut also, as part of that, does digestion, a complex and fascinating subject which is well worth study in itself. Now it might be that the brain does indeed minimise free energy, and that might be a legitimate field of study; but perhaps in doing so it also supports consciousness, a separate issue which like digestion is well worthy of study in itself.

We might not be looking at final answers, then – to be fair, we’ve only scratched the surface of what seems to be a remarkably fecund hypothesis – but even if we’re not, a strange new idea has got to be welcome.

tankardAn exciting new development, as Conscious Entities goes live!  Sergio and I are meeting up for a beer and some ontological elucidation on Monday 16 February at 18.00 in the Plough in Bloomsbury, near the British Museum.  This is more or less the site’s eleventh birthday; I forgot to mark the tenth last year.

I know most readers of the site are not in London, but if you are, even if you’ve never commented here, why not join us?

Drop me an email for contact details, on

e-mail

crimbotSome serious moral dialogue about robots recently. Eric Schwitzgebel put forward the idea that we might have special duties in respect of robots, on the model of the duties a parent owes to children, an idea embodied in a story he wrote with Scott Bakker. He followed up with two arguments for robot rights; first, the claim that there is no relevant difference between humans and AIs, second, a Bostromic argument that we could all be sims, and if we are, then again, we’re not different from AIs.

Scott has followed up with a characteristically subtle and bleak case for the idea that we’ll be unable to cope with the whole issue anyway. Our cognitive capacities, designed for shallow information environments, are not even up to understanding ourselves properly; the advent of a whole host of new styles of cognition will radically overwhelm them. It might well be that the revelation of how threadbare our own cognition really is will be a kind of poison pill for philosophy (a well-deserved one on this account, I suppose).

I think it’s a slight mistake to suppose that morality confers a special grade of duty in respect of children. It’s more that parents want to favour their children, and our moral codes are constructed to accommodate that. It’s true society allocates responsibility for children to their parents, but that’s essentially a pragmatic matter rather than a directly moral one. In wartime Britain the state was happy to make random strangers responsible for evacuees, while those who put the interests of society above their own offspring, like Brutus (the original one, not the Caesar stabber) have sometimes been celebrated for it.

What I want to do though, is take up the challenge of showing why robots are indeed relevantly different to human beings, and not moral agents. I’m addressing only one kind of robot, the kind whose mind is provided by the running of a program on a digital computer (I know, John Searle would be turning in his grave if he wasn’t still alive, but bear with me). I will offer two related points, and the first is that such robots suffer grave problems over identity. They don’t really have personal identity, and without that they can’t be moral agents.

Suppose Crimbot 1 has done a bad thing; we power him down, download his current state, wipe the memory in his original head, and upload him into a fresh robot body of identical design.

“Oops, I confess!” he says. Do we hold him responsible; do we punish him? Surely the transfer to a new body makes no difference? It must be the program state that carries the responsibility; we surely wouldn’t punish the body that committed the crime. It’s now running the Saintbot program, which never did anything wrong.

But then neither did the copy of Crimbot 1 software which is now running in a different body – because it’s a copy, not the original. We could upload as many copies of that as we wanted; would they all deserve punishment for something only one robot actually did?

Maybe we would fall back on the idea that for moral responsibility it has to be the same copy in the same body? By downloading and wiping we destroyed the person who was guilty and merely created an innocent copy? Crimbot 1 in the new body smirks at that idea.

Suppose we had uploaded the copy back into the same body? Crimbot 1 is now identical, program and body, the same as if we had merely switched him off for a minute. Does the brief interval when his data registers had different values make such a moral difference? What if he downloaded himself to an internal store, so that those values were always kept within the original body? What if he does that routinely every three seconds? Does that mean he is no longer responsible for anything, (unless we catch him really quickly) while a version that doesn’t do the regular transfer of values can be punished?

We could have Crimbot 2 and Crimbot 3; 2 downloads himself to internal data storage every second and the immediately uploads himself again. 3 merely pauses every second for the length of time that operation takes. Their behaviour is identical, the reasons for it are identical; how can we say that 2 is innocent while 3 is guilty?

But then, as the second point, surely none of them is guilty of anything? Whatever may be true of human beings, we know for sure that Crimbot 1 had no choice over what to do; his behaviour was absolutely determined by the program. If we copy him into another body, and set him uip wioth the same circumstances, he’ll do the same things. We might as well punish him in advance; all copies of the Crimbot program deserve punishment because the only thing that prevented them from committing the crime would be circumstances.

Now, we might accept all that and suggest that the same problems apply to human beings. If you downloaded and uploaded us, you could create the same issues; if we knew enough about ourselves our behaviour would be fully predictable too!

The difference is that in Crimbot the distinction between program and body is clear because he is an artefact, and he has been designed to work in certain ways. We were not designed, and we do not come in the form of a neat layer of software which can be peeled off the hardware. The human brain is unbelievably detailed, and no part of it is irrelevant. The position of a single molecule in a neuron, or even in the supporting astrocytes, may make the difference between firing and not firing, and one neuron firing can be decisive in our behaviour. Whereas Crimbot’s behaviour comes from a limited set of carefully designed functional properties, ours comes from the minute specifics of who we are. Crimbot embodies an abstraction, he’s actually designed to conform as closely as possible to design and program specs; we’re unresolvably particular and specific.

Couldn’t that, or something like that, be the relevant difference?

datingWhy can’t we solve the problem of consciousness? That is the question asked by a recent Guardian piece.  The account given there is not bad at all; excellent by journalistic standards, although I think it probably overstates the significance of Francis Crick’s intervention.  His book was well worth reading, but in spite of the title his hypothesis had ceased to be astonishing quite a while before. Surely also a little odd to have Colin McGinn named only as Ted Honderich’s adversary when his own Mysterian views are so much more widely cited. Still the piece makes a good point; lots of Davids and not a few Samsons have gone up against this particular Goliath, yet the giant is still on his feet.

Well, if several decades of great minds can’t do the job, why not throw a few dozen more at it? The Edge, in its annual question this year, asks its strike force of intellectuals to tackle the question: What do you think about machines that think? This evoked no fewer than 186 responses. Some of the respondents are old hands at the consciousness game, notably Dan Dennett; we must also tip our hat to our friend Arnold Trehub, who briefly denounces the idea that artefactual machines can think. It’s certainly true, in my own opinion, that we are nowhere near thinkng machines, and in fact it’s not clear that we are getting materially closer: what we have got is splendid machines that clearly don’t think at all but are increasingly good at doing tasks we previously believed needed thought. You could argue that eliminating the need for thought was Babbage’s project right from the beginning, and we know that Turing discarded the question ‘Can machines think?’ as not worthy of an answer.

186 answers is of course, at least 185 more than we really wanted, and those are not good odds of getting even a congenial analysis. In fact, the rapid succession of views, some well-informed, others perhaps shooting from the hip to a degree, is rather exhausting: the effect is like a dreadfully prolonged session of speed dating: like my theory? No? Well don’t worry, there are 180 more on the way immediately. It is sort of fun to surf the wave of punditry, but I’d be surprised to hear that many people were still with the programme when it got to view number 186 (which, despairingly or perhaps refreshingly, is a picture).

Honestly. though, why can’t we solve the problem of consciousness? Could it be that there is something fundamentally wrong? Colin McGinn, of course, argues that we can never understand consciousness because of cognitive closure; there’s no real mystery about it, but our mental toolset just doesn’t allow us to get to the answer.  McGinn makes a good case, but I think that human cognition is not formal enough to be affected by a closure of this kind; and if it were, I think we should most likely remain blissfully unaware of it: if we were unable to understand consciousness, we shouldn’t see any problem with it either.

Perhaps, though, the whole idea of consciousness as conceived in contemporary Western thought is just wrong? It does seem to be the case that non-European schools of philosophy construe the world in ways that mean a problem of consciousness never really arises. For that matter, the ancient Greeks and Romans did not really see the problem the way we do: although ancient philosophers discussed the soul and personal identity, they didn’t really worry about consciousness. Commonly people blame Western dualism for drawing too sharp a division between the world of the mind and the world of material objects: and the finger is usually pointed at Descartes in particular. Perhaps if we stopped thinking about a physical world and a non-physical mind the alleged problem would simply evaporate. If we thought of a world constituted by pure experience, not differentiated into two worlds, everything would seem perfectly natural?

Perhaps, but it’s not a trick I can pull off myself. I’m sure it’s true our thinking on this has changed over the years, and that the advent of computers, for example, meant that consciousness, and phenomenal consciousness in particular, became more salient than before. Consciousness provided the extra thing computers hadn’t got, answering our intuitive needs and itself being somewhat reshaped to fill the role.  William James, as we know, thought the idea was already on the way out in 1904: “A mere echo, the faint rumour left behind by the disappearing ‘soul’ upon the air of philosophy”; but over a hundred years later it still stands as one of the great enigmas.

Still, maybe if we send in another 200 intellectuals…?

BISASusan Schneider’s recent paper argues that when we hear from alien civilisations, it’s almost bound to be super intelligent robots getting in touch, rather than little green men. She builds on Nick Bostrom’s much-discussed argument that we’re all living in a simulation.

Actually, Bostrom’s argument is more cautious than that, and more carefully framed. His claim is that at least one of the following propositions is true:
(1) the human species is very likely to go extinct before reaching a “posthuman” stage;
(2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof);
(3) we are almost certainly living in a computer simulation.

So that if we disbelieve the first two, we must accept the third.

In fact there are plenty of reasons to argue that the first two propositions are true. The first evokes ideas of nuclear catastrophe or an unexpected comet wiping us out in our prime, but equally it could just be that no post human stage is ever reached. We only know about the cultures of our own planet, but two of the longest lived – the Egyptian and the Chinese – were very stable, showing few signs of moving on towards post humanism. They made the odd technological advance, but they also let things slip: no more pyramids after the Old Kingdom; ocean-going junks abandoned before being fully exploited. Really only our current Western culture, stemming from the European Renaissance, has displayed a long run of consistent innovation; it may well be a weird anomaly and its five-hundred year momentum may well be temporary. Maybe our descendants will never go much further than we already have; maybe, thinking of Schneider’s case, the stars are basically inhabited by Ancient Egyptians who have been living comfortably for millions of years without ever discovering electricity.

The second proposition requires some very debatable assumptions, notably that consciousness is computable. But the notion of “simulation” also needs examination. Bostrom takes it that a computer simulation of consciousness is likely to be conscious, but I don’t think we’d assume a digital simulation of digestion would do actual digesting. The thing about a simulation is that by definition it leaves out certain aspects of the real phenomenon (otherwise it’s the phenomenon itself, not a simulation). Computer simulations normally leave out material reality, which could be a problem if we want real consciousness. Maybe it doesn’t matter for consciousness; Schneider argues strongly against any kind of biological requirement and it may well be that functional relations will do in the case of consciousness. There’s another issue, though; consciousness may be uniquely immune from simulation because of its strange epistemological greediness. What do I mean? Well, for a simulation of digestion we can write a list of all the entities to be dealt with – the foods we expect to enter the gut and their main components. It’s not an unmanageable task, and if we like we can leave out some items or some classes of item without thereby invalidating the simulation. Can we write a list of the possible contents of consciousness? No. I can think about any damn thing I like, including fictional and logically impossible entities. Can we work with a reduced set of mental contents? No; this ability to think about anything is of the essence.

All this gets much worse when Bostrom floats the idea that future ancestor simulations might themselves go on to be post human and run their own nested simulations, and so on. We must remember that he is really talking about simulated worlds, because his simulated ancestors need to have all the right inputs fed to them consistently. A simulated world has to be significantly smaller in information terms than the world that contains it; there isn’t going to be room within it to simulate the same world again at the same level of detail. Something has to give.

Without the indefinite nesting, though, there’s no good reason to suppose the simulated ancestors will ever outnumber the real people who ever lived in the real world. I suppose Bostrom thinks of his simulated people as taking up negligible space and running at speeds far beyond real life; but when you’re simulating everything, that starts to be questionable. The human brain may be the smallest and most economic way of doing what the human brain does.

Schneider argues that, given the same Whiggish optimism about human progress we mentioned earlier, we must assume that in due course fleshy humans will be superseded by faster and more capable silicon beings, either because robots have taken over the reins or because humans have gradually cyborgised themselves to the point where they are essentially super intelligent robots. Since these post human beings will live on for billions of years, it’s almost certain that when we make contact with aliens, that will be the kind we meet.

She is, curiously, uncertain about whether these beings will be conscious. She really means that they might be zombies, without phenomenal consciousness. I don’t really see how super intelligent beings like that could be without what Ned Block called access consciousness, the kind that allows us to solve problems, make plans, and generally think about stuff; I think Schneider would agree, although she tends to speak as though phenomenal, experiential consciousness was the only kind.

She concludes, reasonably enough, that the alien robots most likely will have full conscious experience. Moreover, because reverse engineering biological brains is probably the quick way to consciousness, she thinks that a particular kind of super intelligent AI is likely to predominate: biologically inspired superintelligent alien (BISA). She argues that although BISAs might in the end be incomprehensible, we can draw some tentative conclusions about BISA minds:
(i). Learning about the computational structure of the brain of the species that created the BISA can provide insight into the BISAs thinking patterns.
(ii) BISAs may have viewpoint invariant representations. (Surely they wouldn’t be very bright if they didn’t?)
(iii) BISAs will have language-like mental representations that are recursive and combinatorial. (Ditto.)
(iv) BISAs may have one or more global workspaces. (If you believe in global workspace theory, certainly. Why more than one, though – doesn’t that defeat the object? Global workspaces are useful because they’re global.)
(v) A BISA’s mental processing can be understood via functional decomposition.

I’ll throw in a strange one; I doubt whether BISAs would have identity, at least not the way we do. They would be computational processes in silicon: they could split, duplicate, and merge without difficulty. They could be copied exactly, so that the question of whether BISA x was the same as BISA y could become meaningless. For them, in fact, communicating and merging would differ only in degree. Something to bear in mind for that first contact, perhaps.

This is interesting stuff, but to me it’s slightly surprising to see it going on in philosophy departments; does this represent an unexpected revival of the belief that armchair reasoning can tell us important truths about the world?

robot illusionsNeural networks really seem to be going places recently. Last time I mentioned their use in sophisticated translation software, but they’re also steaming ahead with new successes in recognition of visual images. Recently there was a claim from MIT that the latest systems were catching up with primate brains at last. Also from MIT (also via MLU) though, has come an intriguing study into what we could call optical illusions for robots, which cause the systems to make mistakes which are incomprehensible to us primates. The graphics in the grid on the right apparently look like a selection of digits between one and six in the eyes of these recognition systems. Nobody really knows why, because of course neural networks are trained, not programmed, and develop their own inscrutable methods.

How then, if we don’t understand, could we ever create such illusions? Optical illusions for human beings exploit known methods of visual analysis used by the brain, but if we don’t know what method a neural network is using, we seem to be stymied. What the research team did is use one of their systems in reverse, getting it to create images instead of analysing them. These were then evaluated by a similar system and refined through several iterations until they were accepted with a very high level of certainty.

This seems quite peculiar and the first impression is that it rather seriously undermines our faith in the reliability of neural network systems. However, there’s one important caveat to take into account: the networks in question are ‘used to’ dealing with images in which the crucial part to be identified is small in relation to the whole. They are happy ignoring almost all of the image. So to achieve a fair comparison with human recognition we should perhaps think of the question being not ‘do these look like numbers to you?’ and more like ‘can you find one of the digits from one to six hidden somewhere in this image?’. On that basis the results seem easier to understand.

There still seem to be some interesting implications, though. The first is that, as with language, AI systems are achieving success with methods that do not much resemble those used by the human brain. There’s an irony in this happening with neural networks, because in the old dispute between GOFAI and networks it was the network people who were trying to follow a biological design, at least in outline.  The opposition wanted to treat cognition as a pure engineering problem; define what we need, identify the best way to deliver it, and don’t worry about copying the brain. This is the school of thought that likes to point out that we didn’t achieve flight be making machines with flapping, feathery wings. Early network theory, going right back to McCulloch and Pitts, held that we were better off designing something that looked at least broadly like the neurons in the brain. In fact, of course, the resemblance has never been that close, and the focus has generally been more on results than on replicating the structures and systems of biological brains; you could argue that modern neural networks are no more like the brain than fixed-wing aircraft are to birds (or bats).  At any rate, the prospect of equalling human performance without doing it the human way raises the same nightmare scenario I was talking about last time; robots that are not people but get treated as if they were (and perhaps people being treated like machines as a consequence.

A second issue is whether the deception which these systems fall into points to a general weakness. Could it be that these systems work very well when dealing with ‘ordinary’ images but continue go wildly off the rails when faced with certain kinds of unusual ones – even when being pout to practical use? It’s perhaps not very likely that  system is going to run into the kind of truly bizarre image we seem to be dealing with, but a more realistic concern might be the potential scope for sabotage or subversion on the part of some malefactor.  One safeguard against this possibility is that the images in question were designed by, as it were, sister systems, ones that worked pretty much the same way and presumably shared the same quirks. Without owning one of these systems yourself it might be difficult to devise illusions that worked – unless perhaps there are general illusions that all network systems are more or less equally likely to be fooled by? That doesn’t seem very likely, but it might be an interesting research project.  The other safeguard is that these systems are not likely to be used without some additional safeguards, perhaps even more contextual processing of broadly the kind that the human mind obviously brings to the task.

The third question is – what is it like to be an AI deceived by an illusion? There’s no reason to think that these machines have subjective experience – unless you’re one of those who is prepared to grant a dim glow of awareness to quite simple machines – but what if some cyborg with a human brain, or a future conscious robot, had systems like these as part of its processing apparatus rather than the ones provided by the human brain?  It’s not implausible that the immense plasticity of the human brain would allow the inputs to be translated into normal visual experience, or something like it.  On the whole I think this is the most likely result, although there might be quirks or deficits (or hey, enhancements, why not) in the visual experience.  The second possibility is that the experience would be completely weird and inexpressible and although the cyborg/robot would be able to negotiate the world just fine, its experience would be like nothing we’ve ever had, perhaps like nothing we can imagine.

The third possibility is that it would be like nothing. There would be no experience as such; the data and the knowledge about the surroundings would appear in the cyborg/human’s brain but there would be nothing it was like for that to happen.  This is the answer qualophile scpetice would expect for a pure robot brain, but the cyborg is more worrying. Human beings are supposed to experience qualia, but when do they arise? Is it only after all the visual processing has been done – when the data ariive in the ‘Cartesian Theatre’ which Dennett has often told us does not exist? Is it, instead, in the visual processing modules or at the visual processing stage? If so, then we were wrong to doubt that MIT’s systems are not having experiences. Perhaps the cyborg gets flawed or partial qualia – but what would that even mean..?

 

rosetta stoneMicrosoft recently announced the first public beta preview for Skype Translate, a service which will provide immediate translation during voice calls. For the time being only Spanish/English is working but we’re told that English/German and other languages are on the way. The approach used is complex. Deep Neural Networks apparently play a key role in the speech recognition. While the actual translation  ultimately relies on recognising bits of text which resemble those it already knows, the same basic principle applied in existing text translators such as Google Translate, it is also capable of recognising and removing ‘disfluencies’ –  um and ers, rephrasings, and so on, and apparently makes some use of syntactical models, so there is some highly sophisticated processing going on.  It seems to do a reasonable job, though as always with this kind of thing a degree of scepticism is appropriate.

Translating actual speech, with all its messy variability is of course an amazing achievement, much more difficult than dealing with text (which itself is no walk in the park); and it’s remarkable indeed that it can be done so well without the machine making any serious attempt to deal with the meaning of the words it translates. Perhaps that’s a bit too bald: the software does take account of context and as I said it removes some meaningless bits, so arguably it is not ignoring meaning totally. But full-blown intentionality is completely absent.

This fits into a recent pattern in which barriers to AI are falling to approaches which skirt or avoid consciousness as we normally understand it, and all the intractable problems that go with it.  It’s not exactly the triumph of brute force, but it does owe more to processing power and less to ingenuity than we might have expected. At some point if this continues, we’re going to have to take seriously the possibility of our having, in the not-all-that remote future, a machine which mimics human behaviour brilliantly without our ever having solved any of the philosophical problems. Such a robot might run on something like a revival of the frames or scripts of Marvin Minsky or Roger Schank, only this time with a depth and power behind it that would make the early attempts look like working with an abacus. The AI would, at its crudest, simply be recognising situations and looking up a good response, but it would have such a gigantic library of situations and it would be so subtle at customising the details that its behaviour would be indistinguishable from that of ordinary humans for all practical purposes. What would we say about such a robot (let’s call her Sophia, why not since anthropomorphism seems inevitable). I can see several options.

Option one. Sophia really is conscious, just like us. OK, we don’t really understand how we pulled it off, but it’s futile to argue about it when her performance provides everything we could possibly demand of consciousness and passes every test anyone can devise. We don’t argue that photographs are not depictions because they’re not executed in oil paint, so why would we argue that a consciousness created by other means is not the real thing? She achieved consciousness by a different route, and her brain doesn’t work like ours – but her mind does. In fact, it turns out we probably work more like her than we thought: all this talk of real intrinsic intentionality and magic meaningfulness turns out to be a systematic delusion; we’re really just running scripts ourselves!

Option two. Sophia is conscious, but not in the way we are. OK, the results are indistinguishable, but we just know that the methods are different, and so the process is not the same. birds and bats both fly, but they don’t do it the same way. Sophia probably deserves the same moral rights and duties as us, though we need to be careful about that; but she could very well be a philosophical zombie who has no subjective experience. On the other hand, her mental life might have subjective qualities of its own, very different to ours but incommunicable.

Option three. She’s not not conscious; we just know she isn’t, because we know how she works and we know that all her responses and behaviour come from simply picking canned sequences out of the cupboard. We’re deluding ourselves if we think otherwise. But she is the vivid image of a human being and an incredibly subtle and complex entity: she may not be that different from animals whose behaviour is largely instinctive. We cannot therefore simply treat her as a machine: she probably ought to have some kinds of rights: perhaps special robot rights. Since we can’t be absolutely certain that she does not experience real pain and other feelings in some form, and since she resembles us so much, it’s right to avoid cruelty both on the grounds of the precautionary principle and so as not to risk debasing our own moral instincts; if we got used to doling out bad treatment to robots who cried out with human voices, we might get used to doing it to flesh and blood people too.

Option four.  Sophia’s just an entertaining machine, not conscious at all; but that moral stuff is rubbish. It’s perfectly OK to treat her like a slave, to turn her off when we want, or put her through terrible ‘ordeals’ if it helps or amuses us. We know that inside her head the lights are off, no-one home: we might as well worry about dolls. You talk about debasing our moral instincts, but I don’t think treating puppets like people is a great way to go, morally. You surely wouldn’t switch trolleys to save even ten Sophias if it killed one human being: follow that out to its logical conclusion.

Option five. Sophia is a ghastly parody of human life and should be destroyed immediately. I’m not saying she’s actuated by demonic possession (although Satan is pretty resourceful), but she tempts us into diabolical errors about the unique nature of the human spirit.

No doubt there are other options; for me. at any rate, being obliged to choose one is a nightmare scenario. Merry Christmas!