Could the Universe be conscious? This might seem like one of those Interesting Questions To Which The Answer Is ‘No’ that so often provide arresting headlines in the popular press. Since the Universe contains everything, what would it be conscious of? What would it think about? Thinking about itself – thinking about any real thing – would be bizarre, analogous to us thinking about the activity of the  neurons that were doing the thinking. But I suppose it could think about imaginary stuff. Perhaps even the cosmos can dream; perhaps it thinks it’s Cleopatra or Napoleon.

Actually, so far as I can see no-one is actually suggesting the Universe as a whole, as an entity, is conscious. Instead this highly original paper by Gregory L. Matloff starts with panpsychism, a belief that there is some sort of universal field of proto-consciousness permeating the cosmos. That is a not unpopular outlook these days. What’s startling is Matloff’s suggestion that some stars might be able to do roughly what our brains are supposed by panpsychists to do; recruit the field and use it to generate their own consciousness, exerting some degree of voluntary control over their own movements.

He relies for evidence on a phenomenon called Parenago’s discontinuity; cooler, less massive stars seem to circle the galaxy a bit faster than the others. Dismissing a couple of rival explanations, he suggests that these cooler stars might be the ones capable of hosting consciousness, and might be capable of shooting jets from their interior in a consistent direction so as to exert an influence over their own motion. This might be a testable hypothesis, bringing panpsychism in from the debatable realms of philosophy to the rigorous science of astrophysics (unkind people might suggest that the latter field is actually about as speculative as the former; I couldn’t possibly comment).

In discussing panpsychism it is good to draw a distinction between types of consciousness. There is a certain practical decision-making capacity in human consciousness that is relatively well rooted in science in several ways. We can see roughly how it emerged from biological evolution and why it is useful, and we have at least some idea of how neurons might do it, together with a lot of evidence that in fact, they do do it.  Then there is the much mistier business of subjective experience, what being conscious is actually like. We know little about that and it raises severe problems. I think it would be true to claim that most panpsychists think the kind of awareness that suffuses the world is of the latter kind; it is a dim general awareness, not a capacity to make snappy decisions. It is, in my view, one of the big disadvantages of panpsychism that it does not help much with explaining the practical, working kind of consciousness and in fact arguably leaves us with more to account for  than we had on our plate to start with.

Anyway, if Matloff’s theory is to be plausible, he needs to explain how stars could possibly build the decision-making kind of consciousness, and how the universal field would help. To his credit he recognises this – stars surely don’t have neurons – and offers at least some hints about how it might work. If I’ve got it right, the suggestion is that the universal field of consciousness might be identified with vacuum fluctuation pressures, which on the one hand might influence the molecules present in regions of the cooler stars under consideration, and on the other have effects within neurons more or less on Penrose/Hameroff lines. This is at best an outline, and raises immediate and difficult questions; why would vacuum fluctuation have anything to do with subjective experience? If a bunch of molecules in cool suns is enough for conscious volition, why doesn’t the sea have a mind of its own? And so on. For me the deadliest questions are the simplest. If cool stars have conscious control of their movements, why are they all using it the same way – to speed up their circulation a bit? You’d think if they were conscious they would be steering around in different ways according to their own choices. Then again, why would they choose to do anything? As animals we need consciousness to help us pursue food, shelter, reproduction, and so on. Why would stars care which way they went?

I want to be fair to Matloff, because we shouldn’t mock ideas merely for being unconventional. But I see one awful possibility looming. His theory somewhat recalls medieval ideas about angels moving the stars in perfect harmony. They acted in a co-ordinated way because although the angels had wills of their own, they subjected them to God’s. Now, why are the cool stars apparently all using their wills in a similarly co-ordinated way? Are they bound together through the vacuum fluctuations; have we finally found out there the physical manifestation of God? Please, please, nobody go in that direction!

Arnold TrehubRegular readers will be sad to hear that Arnold Trehub,  a fairly regular contributor to discussion on Conscious Entities, died in April.

Consciousness: it’s all theology in the end. Or philosophy, if the distinction matters. Beyond a certain point it is, at any rate; when we start asking about the nature of consciousness, about what it really is. That, in bald summary, seems to be the view of Robert A. Burton in a resigned Nautilus piece. Burton is a neurologist, and he describes how Wilder Penfield first provided really hard and detailed evidence of close, specific correlations between neural and mental events, by showing that direct stimulation of neurons could evoke all kinds of memories, feelings, and other vivid mental experiences. Yet even Penfield, at the close of his career did not think the mind, the spirit of man, could yet be fully explained by science, or would be any time soon; in the end we each had to adopt personal assumptions or beliefs about that.

That is more or less the conclusion Burton has come to. Of course he understands the great achievements of neuroscience, but in the end the Hard Problem, which he seems to interpret rather widely, defeats analysis and remains a matter for theology or philosophy, in which we merely adopt the outlook most congenial to us. You may feel that’s a little dismissive in relation to both fields, but I suppose we see his point. It will be no surprise that Burton dislikes Dennett’s sceptical outlook and dismissal of religion. He accuses him of falling into a certain circularity: Dennett claims consciousness is an illusion, but illusions, after all, require consciousness.

We can’t, of course, dismiss the issues of consciousness and selfhood as completely irrelevant to normal life; they bear directly on such matters as personal responsibility, moral rights, and who should be kept alive. But I think Burton could well argue that the way we deal with these issues in practice tends to vindicate his outlook; what we often see when these things are debated is a clash between differing sets of assumptions rather than a skilful forensic duel of competing reasoning.

Another line of argument that would tend to support Burton is the one that says worries about consciousness are largely confined to modern Western culture. I don’t know enough for my own opinion to be worth anything, but I’ve been told that in classical Indian and Chinese thought the issue of consciousness just never really arises, although both traditions have long and complex philosophical traditions. Indeed, much the same could be said about Ancient Greek philosophy, I think; there’s a good deal of philosophy of mind, but consciousness as we know it just doesn’t really present itself as a puzzle. Socrates never professed ignorance about what consciousness was.

A common view would be that it’s only after Descartes that the issue as we know it starts to take shape, because of his dualism; a distinction between body and spirit that certainly has its roots in the theological (and philosophical) traditions of Western Christianity. I myself would argue that the modern topic of consciousness didn’t really take shape until Turing raised the real possibility of digital computers; consciousness was recruited to play the role of the thing computers haven’t got, and our views on it have been shaped by that perspective over the last fifty years in particular. I’ve argued before that although Locke gives what might be the first recognisable version of the Hard Problem, with an inverted spectrum thought experiment, he actually doesn’t care about it much and only mentions it as a secondary argument about matters that to him, seemed more important.

I think it is true in some respects that as William James said, consciousness is the last remnant of the vanishing soul. Certainly, when people deny the reality of the self, it often seems to me that their main purpose is to deny the reality of the soul. But I still believe that Burton’s view cedes too much to relativism – as I think Fodor once said, I hate relativism. We got into this business – even the theologians – because we wanted the truth, and we’re not going to be fobbed off with that stuff! Scientists may become impatient when no agreed answer is forthcoming after a couple of centuries, but I cling to the idea that there is a truth if the matter about personhood, freedom, and consciousness. I recognise that there is in this, ironically, a tinge of an act of faith, but I don’t care.

Unfortunately, as always things are probably more complicated than that. Could freedom of the will, say, be a culturally relative matter? All my instincts say no, but if people don’t believe themselves to be free, doesn’t that in fact impose some limits on how free they really are? If I absolutely do not believe I’m able to touch the sacred statue, then although the inability may be purely psychological, couldn’t it be real? It seems there are at least some fuzzy edges. Could I abolish myself by ceasing to believe in my own existence? In a way you could say that is in caricature form what Buddhists believe (though they think that correctly understood, my existence was a delusion anyway). That’s too much for me, and not only because of the sort of circularity mentioned above; I think it’s much too pessimistic to give up on a good objective accounts of agency and selfhood.

There may never be a single clear answer that commands universal agreement on these issues, but then there has never been, and never will be, complete agreement about the correct form of human government; but we have surely come on a bit in the last thousand years. To abandon hope of similar gradual consensual progress on consciousness might be to neglect our civic duty. It follows that by reading and thinking about this, you are performing a humane and important task. Well done!

[Next week I return from a long holiday; I’ll leave you to judge whether I make more or less sense.]

A whole set of interesting articles from IEEE Spectrum explore the question of whether AI can and should copy the human brain more. Of course, so-called neural networks were originally inspired by the way the brain works, but they represent a drastic simplification of a partial understanding. In fact, they are so unlike real neurons it’s really rather remarkable that they turn out to perform useful processes at all. Karlheinz Meier provides a useful review of the development of neuromorphic computing, up to contemporary chips with impressive performance.

Jeff Hawkins suggests the brain is better in three ways. First, it learns by rewiring; by growing new synapses. This confers three benefits: learning that is fast, incremental, and continuous. The brain does not need to do lengthy retraining to learn new things. Remarkably, he says a single neurons can do substantial pieces of pattern recognition and acquire ‘knowledge’ of several patterns without them interfering with each other.

The second way in which the brain is better is that it uses sparse distributed representations; a particular idea such as ‘cat’ can be represented by a large number of neurons, with only a small percentage needing to be active at any one time. This makes the system robust in respect of noise and damage, but because some of the ‘cat’ neurons may play roles in the representation of other animals and other entities, it also makes it quick and efficient at recognising similarities and dealing with vague ideas (an animal in the bush which may or may not be a cat).

The third thing the brain does better, according to Hawkins, is sensorimotor integration. He makes the interesting claim that the brain effectively does this all over, as part of basic ordinary activity, not as a specialised central function. Instead of one big 3D model of the world, we have what amounts to little ones everywhere. This is interesting partly because it is, prima facie, so implausible. Doing your modelling a hundred or a million times over is going to use up a lot of energy and ‘processing power’, and it raises the obvious risk of inconsistency between models. But Hawkin’s says he has a detailed theory of how it works and you’d have to be bold to dismiss his claim.

There are several other articles, all worth a look. Actually there are several different reasons we might want to imitate the brain. We might want computers that can interface with humans better because, in part, they work in similar ways. We might want to understand the brain better and be able to test our understanding; an ability that might have real benefits for treating brain disease and injury, and to some degree make up for the ethical limitations on the experiments we can perform on humans. The main focus here, though, is on learning how to do those things the brain does so well, but which still cannot yet be done efficiently, or in some cases at all, by computers.

As a strategy, copying the brain has several drawbacks. First, we still don’t understand the brain well enough. Things have moved on greatly in recent years, but in some ways that just shows how limited our understanding was to begin with. There’s a significant danger that by imitating the brain without understanding, we end up reproducing features that are functionally irrelevant; features the brain has for chance evolutionary reasons. Do we need a brain divided into two halves, as those of vertebrates generally are, or is that unimportant? Second, one thing we do know is that the brain is extraordinarily complex and finely structured. We are never going to reproduce all that in full detail – but perhaps it doesn’t matter; we’ve never replicated the exquisite engineering of feather technology either, but it didn’t stop us doing flight or understanding birds.

I think the challenge of understanding the brain is unique, but trying to copy it is probably an increasingly productive strategy.

What is the moral significance of consciousness? Jim Davies addressed the question in a short but thoughtful piece recently.

Davies quite rightly points out that although the nature of consciousness is often seen as an academic matter, remote from practical concerns, it actually bears directly on how we treat animals and each other (and of course, robots, an area that was purely theoretical not that long ago, but becomes more urgently practical by the day). In particular, the question of which entities are to be regarded as conscious is potentially decisive in many cases.

There are two main ways my consciousness affects my moral status. First, if I’m not conscious, I can’t be a moral subject, in the sense of being an agent (perhaps I can’t anyway, but if I’m not conscious it really seems I can’t get started). Second, I probably can’t be a moral object either; I don’t have any desires that can be thwarted and since I don’t have any experiences, I can’t suffer or feel pain.

Davies asks whether we need to give plants consideration. They respond to their environment and can suffer damage, but without a nervous system it seems unlikely they feel pain. However, pain is a complex business, with a mix of simple awareness of damage, actual experience of that essential bad thing that is the experiential core of pain, and in humans at least, all sorts of other distress and emotional response. This makes the task of deciding which creatures feel pain rather difficult, and in practice guidelines for animal experimentation rely heavily on the broad guess that the more like humans they are, the more we should worry. If you’re an invertebrate, then with few exceptions you’re probably not going to be treated very tenderly. As we come to understand neurology and related science better, we might have to adjust our thinking. This might let us behave better, but it might also force us to give up certain fields of research which are useful to us.

To illustrate the difference between mere awareness of harm and actual pain, Davies suggests the example of watching our arm being crushed while heavily anaesthetised (I believe there are also drugs that in effect allow you to feel the pain while not caring about it). I think that raises some additional fundamental issues about why we think things are bad. You might indeed sit by and watch while your arm was crushed without feeling pain or perhaps even concern. Perhaps we can imagine that for some reason you’re never going to need your arm again (perhaps now you have a form of high-tech psychokinesis, an ability to move and touch things with your mind that simply outclasses that old-fashioned ‘arm’ business), so you have no regrets or worries. Even so, isn’t there just something bad about watching the destruction of such a complex and well-structured limb?

Take a different example; everyone is dead and no-one is ever coming back, not even any aliens. The only agent left is a robot which feels no pleasure or pain but makes conscious plans; it’s a military robot and it spends its time blowing up fine buildings and destroying works of art, for no particular reason. Its vandalistic rampage doesn’t hurt anyone and cannot have any consequences, but doesn’t its casual destructiveness still seem bad?

I’d like to argue that there is a badness to destruction over and above its consequential impact, but it’s difficult to construct a pure example, and I know many people simply don’t share my intuition. It is admittedly difficult because there’s always the likelihood that one’s intuitions are contaminated by ingrained assumptions about things having utility. I’d like to say there’s a real moral rule that favours more things and more organisation, but without appealing to consequentialist arguments it’s hard for me to do much more than note that in fact moral codes tend to inhibit destruction and favour its opposite.

However, if my gut feeling is right, it’s quite important, because it means the largely utilitarian grounds used for rules about animal research and some human matters, re not quite adequate after all; the fact that some piece of research causes no pain is not necessarily enough to stop its destructive character bring bad.

It’s probably my duty to work on my intuitions and arguments a bit more, but that’s hard to do when you’re sitting in the sun with a beer in the charming streets of old Salamanca…

Where did consciousness come from? A recent piece in New Scientist (paywalled, I’m afraid) reviewed a number of ideas about the evolutionary origin and biological nature of consciousness. The article obligingly offered a set of ten criteria for judging whether an organism is conscious or not…

  • Recognises itself in a mirror
  • Has insight into the minds of others
  • Displays regret having made a bad decision
  • Heart races in stressful situations
  • Has many dopamine receptors in its brain to sense reward
  • Highly flexible in making decisions
  • Has ability to focus attention (subjective experience)
  • Needs to sleep
  • Sensitive to anaesthetics
  • Displays unlimited associative learning

This is clearly a bit of a mixed bag. One or two of these have a clear theoretical base; they could be used as the basis of a plausible definition of consciousness. Having insight into the minds of others (‘theory of mind’) is one, and unlimited associative learning looks like another. But robots and aliens need not have dopamine receptors or racing hearts, yet we surely wouldn’t rule out their being conscious on that account. The list is less like notes towards a definition and more of a collection of symptoms.

They’re drawn from some quite different sources, too. The idea that self-awareness and awareness of the minds of others has something to do with consciousness is widely accepted and the piece alludes to some examples in animals. A chimp shown a mirror will touch a spot that had been covertly placed on its forehead, which is (debatably) said to prove it knows that the reflection is itself. A scrub jay will re-hide food if it was seen doing the hiding the first time – unless it was seen only by its own mate. A rat that pressed the wrong lever in an experiment will, it seems, gaze regretfully at the right one (‘What do you do for a living?’ ‘Oh, I assess the level of regret in a rat’s gaze.’) Self-awareness certainly could constitute consciousness if higher-order theories are right, but to me it looks more like a product of consciousness and hence a symptom, albeit a pretty good one.

Another possibility is hedonic variation, here championed by Jesse Prinz and Bjørn Grinde. Many animals exhibit a raised heart rate and dopamine levels when stimulated – but not amphibians or fish (who seem to be getting a bad press on the consciousness front lately). There’s a definite theoretical insight underlying this one. The idea is that assigning pleasure to some outcomes and letting that drive behaviour instead of just running off fixed patterns instinctively, allows an extra degree of flexibility which on the whole has a positive survival value. Grinde apparently thinks there are downsides too and on that account it’s unlikely that consciousness evolved more than once. The basic idea here seems to make a lot of sense, but the dopamine stuff apparently requires us to think that lizards are conscious while newts are not. That seems a fine distinction, though I have to admit that I don’t have enough experience of newts to make the judgement (or of lizards either if I’m being completely honest).

Bruno van Swinderen has a different view, relating consciousness to subjective experience. That, of course, is notoriously unmeasurable according to many, but luckily van Swinderen thinks it correlates with selective attention, or indeed is much the same thing. Why on earth he thinks that remains obscure, but he measures selective attention with some exquisitely designed equipment plugged into the brains of fruit flies. (‘Oh, you do rat regret? I measure how attentively flies are watching things.’)

Sleep might be a handy indicator, as van Swinderen believes it is creatures that do selective attention that need it. They also, from insects to vertebrates (fish are in this time), need comparable doses of anaesthetic to knock them out, whereas nematode worms need far more to stop them in their tracks. I don’t know whether this is enough. I think if I were shown a nematode that had finally been drugged up enough to make it keep still, I might be prepared to say it was unconscious; and if something can become unconscious, it must previously have been conscious.

Some think by contrast that we need a narrower view; Michael Graziano reckons you need a mental model, and while fish are still in, he would exclude the insects and crustaceans van Swinderen grants consciousness to. Eva Jablonka thinks you need unlimited associative learning, and she would let the insects and crustaceans back in, but hesitates over those worms. The idea behind associative learning is again that consciousness takes you away from stereotyped behaviour and allows more complex and flexible responses – in this case because you can, for example, associate complex sets of stimuli and treat them as one new stimulus, quite an appealing idea.

Really it seems to me that all these interesting efforts are going after somewhat different conceptions of consciousness. I think it was Ned Block who called it a ‘mongrel’ concept; there’s little doubt that we use it in very varied ways, to describe the property of a worm that’s still moving at one end, to the ability to hold explicit views about the beliefs of other conscious entities at the other. We don’t need one theory of consciousness, we need a dozen.

Is Karl Friston that bloke? You know who I mean. That really clever bloke, master of some academic field. He’s used to understanding a few important things far better than the rest of us. But when people in the pub start discussing philosophy of mind, he feels wrong-footed in this ill-defined territory.

“You see,” he says, “the philosophers make such a meal of this, with all their vague,  mystical talk of intentions and experiences. But I’m a simple man, and I can’t help looking at it as a scientist.  To me it just seems obvious that it’s basically nothing more than a straightforward matter of polyvalent symmetry relations between vectors in high-order Minkowski topologies, isn’t it?

Aha! Now you have to meet him on his own turf and defeat him there: otherwise you can’t prove he hasn’t solved the problem of consciousness!

I’m sure that isn’t really Friston at all; but his piece in Aeon, perhaps due to its unavoidable brevity, seems to invoke some relatively esoteric apparatus while ultimately saying things that turn out to be either madly optimistic or relatively banal. Let’s quickly canter through it.  Friston starts by complaining of philosophers and cognitive scientists who insist that the mind is a thing.   “As a physicist and psychiatrist,” he says ” I find it difficult to engage with conversations about consciousness.”  In physics, he says, it’s dangerous to assume that that things ‘exist’; the real question is what processes give rise to the notion that something exists. (An unexpected view: physics, then, seeks to explain the notions in our minds, not external reality? Poor old Isaac Newton wasn’t really doing proper physics at all.) Friston, instead, wants to brush all that ‘thing’ nonsense aside and argue that consciousness, in reality, is a natural process.

I’ve spent some time trying to think of anyone who would deny that, and really I’ve come up empty. Panpsychists probably think that at the most fundamental level consciousness can be a very simple form of awareness, too simple to go through complex changes: but even they, I think, would not deny that human consciousness is a natural process. Perhaps all Friston means is that he doesn’t want to spend any time on definitions of consciousness; that territory is certainly a treacherous swamp where people get lost, although setting out to understand something you haven’t defined can be kinda bold, too.

To illustrate the idea of consciousness as a process, Friston (inexplicably, to me anyway: this is one of the places where I feel something might have got lost in editing) suggests we swap the word and talk about whether evolution is a process. Scientifically, he says, we know that evolution isn’t for anything – it’s just a process that happens. Since consciousness is a product of evolution, it isn’t for anything either. I don’t know about that; it’s true it can’t borrow its purpose from evolution if evolution doesn’t have one; the thing is, putting aside all the difficult issues of ultimate purpose and the nature of teleology, there is a well-established approach within evolutionary theory of asking what, say, horns or eyes are for (defeating rivals, seeing food, etc). This is just a handy way to ask about the survival value of particular adaptations. So within evolution things like consciousness can be for something in a relatively clear sense without evolution itself having to be for anything. Actually Friston understands this perfectly well; he immediately goes on to speak approvingly of Dennett’s free-floating rationales, just the kind of intra-evolutionary purpose I mean. (He says Dennett has spent his career trying to understand the origin of the mind – what, is he one of those pesky guys who treat the mind as a thing?)

Anyway, now we’re getting nearer to the real point; inference.  Inference, claims Friston, is quite close to a theory of everything (maybe, but so is ‘stuff happens’). First, though, it seems we need to talk about complex systems, and we’re going to do it by talking about their state spaces. I wish we weren’t. Really, this business of state spaces is like a fashion – or a disease – sweeping through certain parts of the intellectual community. Is there an emerging belief, comparable to the doctrine of the Universality of Computation, that everything must be usefully capable of analysis by state space? I might be completely up the creek , but it seems to me it’s all too easy to use  hypothetical state spaces to give yourself a false assurance that something is tractable when it really isn’t. Of course proper defined state spaces are perfectly legitimate in certain cases. Friston mentions quantum systems; yes, but elementary particles have a relatively small number of properties that provide a manageable number of regular axes from which our space can be constructed. At least you’ve got to be able to say what variables you’re mapping in your space, haven’t you? Here it seems Friston wants to talk about, for example, the space of electrochemical states of the brain. I mean, he’s a professor of neurology, so he knows whereof he speaks – but what on earth are the unimaginable axes that define that one, using cleanly separated independent variables? He’s very hand-wavy about this; he half-suggests we might be dealing with a state space detailing the position of every particle, but surely that’s radically below the level of description we need even for neurology, never mind inferences about the world. It’s highly likely that mental states are uniquely resistant to simple analysis; in the state space of human thoughts every one of the infinite possible thoughts may be adjacent to every other along one of the infinite number of salient axes. I doubt whether God could construct that state space meaningfully, not even even if we gave Him a pencil and paper.

Anyway, Friston wants us to consider a Lyapunov function applied to some suitable state space of – I think – a complex system such as one of us, ie a living organism. He describes the function in general terms and how it governs movement through the space, although without too much detail. In fact after a bit of a whistle stop tour of attractors and homeostasis all he seems to want from the discussion is the point that adaptive behaviour can be read as embodying inferences about the world the organism inhabits. We could get there just by talking about hibernation or bees building hives, so the unkind suspicion crossed my mind that he brings Lyapunov into it partly in order to have a scary dead Russian on the team. I’m sure that’s unfair, and most likely there is illuminating detail about the Lyapunov function that didn’t survive into this account because of limitations on space (or probable reader comprehension). In any case it seems that all we really need to take away is that this function in complex systems like us can be interpreted as making inferences about the future, or minimising ‘surprise’.

It’s important to be clear here that we’re not actually talking literally about actual surprise or about actual inference, the process of some conscious entity inferring something. We’re using the word metaphorically to talk about the free-floating explanations, in a Dennettian sense, that complex, self-maintaining systems implicitly display. By acting in ways that keep them going, such systems can sort of be said to embody guesses about the future. Friston says these sorts of behaviour in complex systems ‘effectively’ make inferences about the world; this is one of those cases where we should remember that ‘effectively’ should strictly be read as ‘don’t’. It’s absolutely OK to talk in these metaphorical terms – I’d go so far as to say it’s almost unavoidable – but to talk of metaphorical inference in an account of consciousness, where we’re trying to explain the real thing, raises the obvious risk of losing track and kidding ourselves that we’ve solved the problem of cognition when all we’ve done is invoke a metaphor. So let’s call this kind of metaphorical inference ‘minference’. If we want to claim later that inference is minference, or that we can build inference out of minference, well and good: but we’ll be sure of noticing what we’re doing.

So complex, self-sustaining systems like us do minference; but that tells us nothing about consciousness because it’s true of all such systems. It’s true of plants and bacteria just as much as it’s true of us, and it’s even true of some non-living systems. Of course, says Friston, but for similar reasons consciousness must also be a process of inference (minference).  It’s just the (m)inference done by the brain. That’s fine, but it just tells us consciousness must tend to produce behaviour that helps us stay alive, without telling us anything at all about the distinctive nature of the process; digestion is also a process that does minference, isn’t it? But we don’t usually attribute consciousness to the gut. Brain minference is entirely different to conscious explicit inferences.

Friston does realise that he needs to explain the difference between conscious and non-conscious minferring creatures, but I don’t think he’s clear enough that the earlier talk of (m)inference is no real use to him. He suggests that in order to infer (really infer) the consequences of its actions, a creature needs an internal model. This seems quite problematic to me, though I’m led to believe he has a more extensive argument for it which doesn’t appear here. While we may use models for some purposes, I honestly don’t see that inference requires one (in fact, building a model and then making your inferences about that would be asking for trouble). I plan to go and catch a train in a minute, having inferred that there will be one at the station; does that mean I must have a small train set or a miniature timetable simulated in my brain? Nope. Friston wants to say that the difference between conscious and unconscious behaviour is that the former derives from a ‘thick’ model of time, which here seems to mean no more than one that takes account of a relatively extended period. The idea that the duration is crucial makes no great sense to me: the behaviour patterns of ants reflect hundreds of thousands or even millions of years of minference: my conscious decisions may be the work of a moment; but I think in the end what Friston means to say is that conscious thought detaches us from the immediate moment by modelling the world and so allows us to entertain plans motivated by long-term considerations. That’s fine, but it has nothing much to do with the state spaces, attractors and Lyapunov functions discussed earlier; it looks as if we can junk all that and just start afresh with the claim about consciousness being a matter of a model that helps us plan. And once that idea is shorn of all the earlier apparatus it becomes clear that it’s not an especially new insight. In fact, it’s pretty much the sort of thing a lot of those pesky mind-as-thing fellows have been saying all along.

Alas, it’s worse than that. Because of the confusion between inference and minference Friston seems to be saddled with the idea that actual consciousness is about minimising actual surprise. Is the animating purpose of human thought to avoid surprise? Do our explicit mental processes seek above all to attain a steady equilibrium, always thinking about the same few things in a tight circle and getting away from new ideas as quickly as possible? It doesn’t seem plausible to me.

Friston concludes with these two sentences.

There’s no real reason for minds to exist; they appear to do so simply because existence itself is the end-point of a process of reasoning. Consciousness, I’d contend, is nothing grander than inference about my future.

Frankly, I don’t understand the first one; the second is fine, but I’m left with the nagging feeling that I missed something more exciting along the way?


[The picture is Lyapunov, bu the way, not Karl Friston]


Matt Faw says subjective experience is caused by a simulation in the hippocampus – a bit like a holodeck. There’s a brief description on the Brains Blog, with the full version here.

In a very brief sketch, Faw says that data from various systems is pulled together in the hippocampal system and compiled into a sort of unified report of what’s going on. This is sort of a global workspace system, whose function is to co-ordinate. The ongoing reportage here is like a rolling film or holodeck simulation, and because it’s the only unified picture available, it is mistaken for the brain’s actual interaction with the world. The actual work of cognition is done elsewhere, but this simulation is what gives rise to ‘neurotypical subjective experience’.

I’m uneasy about that; it doesn’t much resemble what I would call subjective experience. We can have a model of the self in the world without any experiencing going on (Roger Penrose suggested the example of a video camera pointed at a mirror), while the actual subjectivity of phenomenal experience seems to be nothing to do with the ‘structural’ properties of whether there’s a simulation of the world going on.

I believe the simulation or model is supposed to help us think about the world and make plans; but the actual process of thinking about things rarely involves a continuous simulation of reality. If I’m thinking of going out to buy a newspaper, I don’t have to run through imagining what the experience is going to be like; indeed, to do so would require some effort. Even if I do that, I’m the puppeteer throughout; it’s not like running a computer game and being surprised by what happens. I don’t learn much from the process.

And what would the point be? I can just think about the world. Laboriously constructing a model of the world and then thinking about that instead looks like a lot of redundant work and a terrible source of error if I get it wrong.

There’s a further problem for Faw in that there are people who manage without functioning hippocampi. Although they undoubtedly have serious memory problems, they can talk to us fairly normally and answer questions about their experiences. It seems weird to suggest that they don’t have any subjective experience; are they philosophical zombies?

Faw doesn’t want to say so. Instead he likens their thought processes to the ones that go on when we’re driving without thinking. Often we find we’ve driven somewhere but cannot remember any details of the journey. Faw suggests that what happens here is just that we don’t remember the driving. All the functions that really do the cognitive work are operating normally, but whereas in other circumstances their activity would get covered (to some extent) in the ‘news bulletin’ simulation, in this case our mind is dealing with something more interesting (a daydream, other plans, whatever), and just fails to record what we’ve done with the brake and the steering wheel. But if we were asked at the very moment of turning left what we were doing, we’d have no problem answering. People with no hippocampi are like this; constantly aware of the detail of current cognition, stuff that is normally hidden from neurotypically normal people, but lacking the broader context which for us is the source of normal conscious experience.

I broadly like this account, and it points to the probability that the apparent problems for Faw are to a degree just a matter of labelling. He’s calling it subjective experience, but if he called it reportable subjective experience it would make a lot of sense. We only ever report what we remember to have been our conscious experience: some time, even if only an instant, has to have passed. It’s entirely plausible that that we rely on the hippocampus to put together these immediate, reportable memories for us.

So really what I call subjective experience is going on all the time out there; it doesn’t require a unified account or model; but it does need the hippocampal newsletter in order to become reportable. Faw and I might disagree on the fine philosophical issue of whether it is meaningful to talk about experiences that cannot, in principle, be reported; but in other ways we don’t really differ as much as it seemed.

Is this a breakthrough in robot emotion? Zhou et al describe the Emotional Chatting Machine (ECM), a chatbot which uses machine learning to return answers with a specified emotional tone.

The ultimate goal of such bots is to produce a machine that can detect the emotional tone of an input and choose the optimum tone for its response, but this is very challenging. It’s not simply a matter of echoing the emotional tone of the input; the authors suggest for example, that sympathy is not always the appropriate response to a sad story. For now, the task they address is to take two inputs; the actual content and a prescribed emotional tone, and generate a response to the content reflecting the required tone. Actually, doing more than reflecting is going to be very challenging indeed because the correct tone of a response ought to reflect the content as well as the tone of the input; if someone calmly tells you they’re about to die, or about to kill someone else, an equally calm response may not be emotionally appropriate (or it could be in certain contexts; this stuff is, to put it mildly, complex).

To train the ECM, two databases were used. The NLPCC dataset has 23,105 sentences collected from Weibo, a Chinese blog site, and categorised by human beings using eight categories: Anger, Disgust, Fear, Happiness, Like, Sadness, Surprise and Other. Fear and Surprise turned up too rarely on Weibo blogs to be usable in practice.

Rather than using the NLPCC dataset directly, the researchers used it to train a classifier which then categorised the larger STC dataset, which has 219,905 posts and 4,308,211 responses; they reckon they achieved an accuracy of 0.623, which doesn’t sound all that great, but was apparently good enough to work with; obviously this is something that could be improved in future. It was the ’emotionalised’ STC data set which was then used to train the ECM for its task.

Results were assessed by human beings for both naturalness (how human they seemed) and emotional accuracy; ECM improved substantially on other approaches and generally turned in a good performance, especially on emotional accuracy. Alas, the chattbot is not available to try out online.

This is encouraging but I have a number of reservations. The first is about the very idea of an emotional chatbot. Chatbots are almost by definition superficial. They don’t attempt to reproduce or even model the processes of thought that underpin real conversation, and similarly they don’t attempt to endow machines with real or even imitation emotion (the ECM has internal and external memory in which to record emotional states, but that’s as far as it goes). Their performance is always, therefore, on the level of a clever trick.

Now that may not matter, since the aim is merely to provide machines that deal better with emotional human beings. They might be able to do that without having anything like real or even model emotions themselves (we can debate the ethical implications of ‘deceiving’ human interlocutors like this another time). But there must be a worry that performance will be unreliable.

Of course, we’ve seen that by using large data sets, machines can achieve passable translations without ever addressing meanings; it is likely enough that they can achieve decent emotional results in the same sort of way without ever simulating emotions in themselves. In fact the complexity of emotional responses may make humans more forgiving than they are for translations, since an emotional response which is slightly off can always be attributed to the bot’s personality, mood, or other background factors. On the other hand, a really bad emotional misreading can be catastrophic, and the chatbot approach can never eliminate such misreading altogether.

My second reservation is about the categorisation adopted. The eight categories adopted for the NLPCC data set, and inherited here with some omissions, seem to belong to a family of categorisations which derive ultimately from the six-part one devised by Paul Ekman: anger, disgust, fear, happiness, sadness, and surprise. The problem with this categorisation is that it doesn’t look plausibly comprehensive or systematic. Happiness and sadness look like a pair, but there’s no comparable positive counterpart of disgust or fear, for example.  These problems have meant that the categories are often fiddled with. I conjecture that ‘like’ was added to the NLPCC set as a counterpart to disgust, and ‘other’ to ensure that everything could be categorised somewhere. You may remember that n the Pixar film Inside Out Surprise didn’t make the cut; some researchers have suggested that only four categories are really solid, with fear/surprise and anger/disgust forming pairs that are not clearly distinct.

The thing is, all these categorisations are rooted in attempts to categorise facial expressions. It isn’t the case that we necessarily have a distinct facial expression for every possible emotions, so that gives us an incomplete and slightly arbitrary list. It might work for a bot that pulled faces, but one that provides written outputs needs something better. I think a dimensional approach is better; one that defines emotions in terms of a few basic qualities set out along different axes. These might be things like attracted/repelled, active/passive, ingoing/outgoing or whatever. There are many models along these lines and they have a long history in psychology; they offer better assurance of a comprehensive account and a more hopeful prospect of a reductive explanation.

I suppose you also have to ask whether we want bots that respond emotionally. The introduction of cash machines reduced the banks’ staff costs, but I believe they were also popular because you could get your money without having to smile and talk. I suspect that in a similar way we really just want bots to deliver the goods (often literally), and their lack of messy humanity is their strongest selling point. I suspect though, that in this respect we ain’t seen nothing yet…

Do we need robots to be conscious? Ryota Kanai thinks it is largely up to us whether the machines wake up – but he is working on it. I think his analysis is pretty good and in fact I think we can push it a bit further.

His opening remarks, perhaps due to over-editing, don’t clearly draw the necessary distinction between Hard and Easy problems, or between subjective p-consciousness and action-related a-consciousness (I take it to be the same distinction, though not everyone would agree). Kanai talks about the unsolved mystery of experience, which he says is not a necessary by-product of cognition, and says that nevertheless consciousness must be a product of evolution. Hm. It’s p-consciousness, the ineffable, phenomenal business of what experience is like, that is profoundly mysterious, not a necessary by-product of cognition, and quite possibly nonsense. That kind of consciousness cannot in any useful sense be a product of evolution, because it does not affect my behaviour, as the classic zombie twin thought experiment explicitly demonstrates.  A-consciousness, on the other hand, the kind involved in reflecting and deciding, absolutely does have survival value and certainly is a product of evolution, for exactly the reasons Kanai goes on to discuss.

The survival value of A-consciousness comes from the way it allows us to step back from the immediate environment; instead of responding to stimuli that are present now, we can respond to ones that were around last week, or even ones that haven’t happened yet; our behaviour can address complex future contingencies in a way that is both remarkable and powerfully useful. We can make plans, and we can work out what to do in novel situations (not always perfectly, of course, but we can do much better than just running a sequence of instinctive behaviour).

Kanai discusses what must be about the most minimal example of this; our ability to wait three seconds before responding to a stimulus. Whether this should properly be regarded as requiring full consciousness is debatable, but I think he is quite right to situate it within a continuum of detached behaviour which, further along, includes reactions to very complex counterfactuals.

The kind he focuses on particularly is self-consciousness or higher-order consciousness; thinking about ourselves. We have an emergent problem, he points out, with robots  whose reasons are hidden; increasingly we cannot tell why a complex piece of machine learning resulted in the behaviour that resulted. Why not get the robot to tell us, he says; why not enable it to report its own inner states? And if it becomes able to consider and explain its own internal states, won’t that be a useful facility which is also like the kind of self-reflecting consciousness that some philosophers take to be the crucial feature of the human variety?

There’s an immediate and a more general objection we might raise here. The really bad problem with machine learning is not that we don’t have access to the internal workings of the robot mind; it’s really that in some cases there just is no explanation of the robot’s behaviour that a human being can understand. Getting the robot to report will be no better than trying to examine the state of the robot’s mind directly; in fact it’s worse, because it introduces a new step into the process, one where additional errors can creep in. Kanai describes a community of AIs, endowed with a special language that allows them to report their internal states to each other. It sounds awfully tedious, like a room full of people who, when asked ‘How are you?’ each respond with a detailed health report. Maybe that is quite human in a way after all.

The more general theoretical objection (also rather vaguer, to be honest) is that, in my opinion at least, Kanai and those Higher Order Theory philosophers just overstate the importance of being able to think about your own mental states. It is an interesting and important variety of consciousness, but I think it just comes for free with a sufficiently advanced cognitive apparatus. Once we can think about anything, then we can of course think about our thoughts.

So do we need robots to be conscious? I think conscious thought does two jobs for us that need to be considered separately although they are in fact strongly linked. I think myself that consciousness is basically recognition. When we pull off that trick of waiting for three seconds before we respond to a stimulus, it is because we recognise the wait as a thing whose beginning is present now, and can therefore be treated as another present stimulus. This one simple trick allows us to respond to future things and plan future behaviour in a way that would otherwise seem to contradict the basic principle that the cause must come before effect.

The first job that does is allow the planning of effective and complex actions to achieve a given goal. We might want a robot to be able to do that so it can acquire the same kind of effectiveness in planning and dealing with new situations which we have ourselves, a facility which to date has tended to elude robots because of the Frame Problem and other issues to do with the limitations of pre-programmed routines.

The second job is more controversial. Because action motivated by future contingencies has a more complex causal back-story, it looks a bit spooky, and it is the thing that confers on us the reality (or the illusion, if you prefer) of free will and moral responsibility. Because our behaviour comes from consideration of the future, it seems to have no roots in the past, and to originate in our minds. It is what enables us to choose ‘new’ goals for ourselves that are not merely the consequence of goals we already had. Now there is an argument that we don’t want robots to have that. We’ve got enough people around already to originate basic goals and take moral responsibility; they are a dreadful pain already with all the moral and legal issues they raise, so adding a whole new category of potentially immortal electronic busybodies is arguably something best avoided. That probably means we can’t get robots to do job number one for us either; but that’s not so bad because the strategies and plans which job one yields can always be turned into procedures after the fact and fed to ‘simple’ computers to run. We can, in fact, go on doing things the way we do them now; humans work out how to deal with a task and then give the robots a set of instructions; but we retain personhood, free will, agency and moral responsibility for ourselves.

There is quite a big potential downside, though; it might be that the robots, once conscious, would be able to come up with better aims and more effective strategies than we will ever be able to devise. By not giving them consciousness we might be permanently depriving ourselves of the best possible algorithms (and possibly some superior people, but that’s a depressing thought from a human point of view). True, but then I think that’s almost what we are on the brink of doing already. Kanai mentions European initiatives which may insist that computer processes come with an explanation that humans can understand; if put into practice the effect, once the rule collides with some of those processes that simply aren’t capable of explanation, would be to make certain optimal but inscrutable algorithms permanently illegal.

We could have the best of both worlds if we could devise a form of consciousness that did job number one for us without doing job two as an unavoidable by-product, but since in my view they’re all acts of recognition of varying degrees of complexity, I don’t see at the moment how the two can be separated.