The new film Self/less is based around the transfer of consciousness. An old man buys a new body to transfer into, and then finds that contrary to what he was told, it wasn’t grown specially: there was an original tenant who moreover, isn’t really gone. I understand that this is not a film that probes the metaphysics of the issue very deeply; it’s more about fight scenes; but the interesting thing is how readily we accept the idea of transferred consciousness.
In fact, it’s not at all a new idea; if memory serves, H.G.Wells wrote a short story on a similar theme; a fit young man with no family is approached by a rich old man in poor health who apparently wants to leave him all his fortune; then he finds himself transferred unwillingly to the collapsing ancient body and the old man making off in his fresh young one. In Wells’ version the twist is that the old man gets killed in a chance traffic accident, thereby dying before his old body does anyway.
The thing is, how could a transfer possibly work? In Wells’ story it’s apparently done with drugs, which is mysterious; more normally there’s some kind of brain-transfer helmet thing. It’s pretty much as though all you needed to do was run an EEG and then reverse the polarity. That makes no sense. I mean, scanning the brain in sufficient detail is mind-boggling to begin with, but the idea that you could then use much the same equipment to change the content of the mind is in another league of bogglement. Weather satellites record the meteorology of the world, but you cannot use them to reset it. This is why uploading your mind to a computer, while highly problematic, is far easier to entertain than transferring it to another biological body.
The big problem is that part of the content of the brain is, in effect, structural. It depends on which neurons are attached to which (and for that matter, which neurons there are), and on the strength and nature of that linkage. It’s true that neural activity is important too, and we can stimulate that electrically; even with induction gear that resembles the SF cliché: but we can’t actually restructure the brain that way.
The intuition that transfers should be possible perhaps rests on an idea that the brain is, as it were, basically hardware, and consciousness is essentially software; but isn’t really like that. You can’t run one person’s mind on another’s brain.
There is in fact no reason to suppose that there’s much of a read-across between brains: they may all be intractably unique. We know that there tends to be a similar regionalisation of functions in the brain, but there’s no guarantee that your neural encoding of ‘grandmother’ resembles mine or is similarly placed. Worse, it’s entirely possible that the ‘meaning’ of neural assemblages differs according to context and which other structures are connected, so that even if I could identify my ‘grandmother’ neurons, and graft them in in place of yours, they would have a different significance, or none.
Perhaps we need a more sophisticated and bespoke approach. First we thoroughly decipher both brains, and learn their own idiosyncratic encoding works. Then we work out a translator. This is a task of unimaginable complexity and particularity, but it’s not obviously impossible in principle. I think it’s likely that for each pair of brains you would need a unique translator: a universal one seems such an heroic aspiration that I really doubt its viability: a universal mind map would be an achievement of such interest and power that merely transferring minds would seem like time-wasting games by comparison.
I imagine that even once a translator had been achieved, it would normally only achieve partial success. There would be a limit to how far you could go with nano-bot microsurgery; and there might be certain inherent limitations. Certain ideas, certain memories, might just be impossible to accommodate in the new brain because of their incompatibility with structural or conceptual issues that were too deeply embedded to change; there would be certain limitations. The task you were undertaking would be like the job of turning Pride and Prejudice into Don Quixote simply by moving the words around and perhaps in a few key cases allowing yourself one or two anagrams: the result might be recognisable, but it wouldn’t be perfect. The transfer recipient would believe themselves to be Transferee, but they would have strange memory gaps and certain cognitive deficits, perhaps not unlike Alzheimer’s, as well as artefacts: little beliefs or tendencies that existed neither in Transferee or Recipient, but were generated incidentally through the process of reconstruction.
It’s a much more shadowy and unappealing picture, and it makes rather clearer the real killer: that though Recipient might come to resemble Transferee, they wouldn’t really be them.
In the end, we’re not data, or a program; we’re real and particular biological entities, and as such our ontology is radically different. I said above that the plausibility of transfers comes from thinking of consciousness as data, which I think is partly true: but perhaps there’s something else going on here; a very old mental habit of thinking of the soul as detachable and transferable. This might be another case where optimists about the capacity of IT are unconsciously much less materialist than they think.
The new film Self/less is based around the transfer of consciousness. An old man buys a new body to transfer into, and then finds that contrary to what he was told, it wasn’t grown specially: there was an original tenant who moreover, isn’t really gone. I understand that this is not a film that probes the metaphysics of the issue very deeply; it’s more about fight scenes; but the interesting thing is how readily we accept the idea of transferred consciousness.
It’s quite a complex, thoughtful paper, but the gist is clearly that consciousness doesn’t really do that much. The authors take the view that many functions generally regarded as conscious are in fact automatic and pre- or un-conscious: what consciousness hosts is not the process but the results. It looks to consciousness as though it’s doing the work, but really it isn’t.
In itself this is not a new view, of course. We’ve heard of other theories that base their interpretation on the idea that consciousness only deals with small nuggets of information fed to it by unconscious processes. Indeed, as the authors acknowledge, some take the view that consciousness does nothing at all: that it is an epiphenomenon, a causal dead end, adding no more to human behaviour than the whistle adds to the locomotive.
Morsella et al don’t go that far. In their view we’re lacking a clear idea of the prime function of consciousness; their Passive Frame Theory holds that the function is to constrain and direct skeletal muscle output, thereby yielding adaptive behaviour. I’d have thought quite a lot of unconscious processes, even simple reflexes, could be said to do that too; philosophically I think we’d look for a bit more clarity about the characteristic ways in which consciousness as opposed to instinct or other unconscious urges influence behaviour; but perhaps I’m nit-picking.
The authors certainly offer explanation as to what consciousness does. In their view, well-developed packages are delivered to consciousness from various unconscious functions. In consciousness these form a kind of combinatorial jigsaw, very regularly refreshed in a conscious/unconscious cycle; the key thing is that these packages are encapsulated and cannot influence each other. This is what distinguishes the theory from the widely popular idea of a Global Workspace, originated by Bernard Baars; no work is done on the conscious contents while they’re there. they just sit until refreshed or replaced.
The idea of encapsulation is made plausible by various examples. When we recognise an illusion, we don’t stop experiencing it; when we choose not to eat, we don’t stop feeling hungry, and so on. It’s clearly the case that sometimes this happens, but can we say that there are really no cases where one input alters our conscious perception of another? I suspect that any examples we might come up with would be deemed by Morsella et al to occur in pre-conscious processing and only seem to happen in consciousness: the danger with that is that the authors might end up simply disqualifying all counter-examples and thereby rendering their thesis unfalsifiable. It would help if we could have a sharper criterion of what is, and isn’t, within consciousness.
As I say, the authors do hold that consciousness influences behaviour, though not by its own functioning; instead it does so by, in effect, feeding other unconscious functions. An analogy with the internet is offered: the net facilitates all kind of functions; auctions, research, social interaction, filling the world with cat pictures, and so on; but it would be quite right to say that in itself it does any of these things.
That’s OK, but it seems to delegate an awful lot of things that we might have regarded as conscious cognitive activity to these later unconscious functions, and it would help to have more of an account of how they do their thing and how consciousness contrives to facilitate. It seems it merely brings things together, but how does that help? If they’re side by side but otherwise unprocessed, I’m not sure what the value of merely juxtaposing them (in some sense which is itself a little unclear) amounts to.
So I think there’s more to do if Passive Frame Theory is going to be a success; but it’s an interesting start.
The recent short NYT series on robots has a dying fall. The articles were framed as an investigation of how robots are poised to change our world, but the last piece is about the obsolescence of the Aibo, Sony’s robot dog. Once apparently poised to change our world, the Aibo is no longer made and now Sony will no longer supply spare parts, meaning the remaining machines will gradually cease to function.
There is perhaps a message here about the over-selling and under-performance of many ambitious AI projects, but the piece focuses instead on the emotional impact that the ‘death’ of the robot dogs will have on some fond users. The suggestion is that the relationship these owners have with their Aibo is as strong as the one you might have with a real dog. Real dogs die, of course, so though it may be sad, that’s nothing new. Perhaps the fact that the Aibos are ‘dying’ as the result of a corporate decision, and could in principle have been immortal makes it worse? Actually I don’t know why Sony or some third party entrepreneur doesn’t offer a program to virtualise your Aibo, uploading it into software where you can join it after the Singularity (I don’t think there would really be anything to upload, but hey…).
On the face of it, the idea of having a real emotional relationship with an Aibo is a little disturbing. Aibos are neat pieces of kit, designed to display ’emotional’ behaviour, but they are not that complex (many orders of magnitude less complex than a dog, surely), and I don’t think there is any suggestion that they have any real awareness or feelings (even if you think thermostats have vestigial consciousness, I don’t think an Aibo would score much higher. If people can have fully developed feelings for these machines, it strongly suggests that their feelings for real dogs have nothing to do with the dog’s actual mind. The relationship is essentially one-sided; the real dog provides engaging behaviour, but real empathy is entirely absent.
More alarming, it might be thought to imply that human relationships are basically the same. Our friends, our loved ones, provide stimuli which tickle us the right way; we enjoy a happy congruence of behaviour patterns, but there is no meeting of minds, no true understanding. What’s love got to do with it, indeed?
Perhaps we can hope that Aibo love is actually quite distinct from dog love. The people featured in the NYT video are Japanese, and it is often said that Japanese culture is less rigid about the distinction between animate and inanimate than western ideas. In Christianity, material things lack souls and any object that behaves as if it had one may be possessed or enchanted in ways that are likely to be unnatural and evil. In Shinto, the concept of kami extends to anything important or salient, so there is nothing unnatural or threatening about robots. But while that might validate the idea of an Aibo funeral, it does not precisely equate Aibos and real dogs.
In fact, some of the people in the video seem mainly interested in posing their Aibos for amusing pictures or video, something they could do just as well with deactivated puppets. Perhaps in reality Japanese culture is merely more relaxed about adults amusing themselves with toys?
Be that as it may, it seems that for now the era of robot dogs is already over…
A few weeks ago, Peter was kind enough to publish my personal reflections on computational functionalism, I made it quite clear that the aim was to receive feedback and food for thought, particularly in the form of disagreements and challenges. I got plenty, more than I deserve, so a big “thank you” is in order, to all the contributors and to Peter for making it all possible. The discussions that are happening here somehow vindicate the bad rep that the bottom half of the internet gets. Over the last week or so, I’ve been busy trying to summarise what I’ve learned, what challenges I find unanswerable and what answers fail to convince. This is hard to do, as even if we have all tried hard to remain on topic, our subject is slippery and comes with so much baggage, so apologies if I’ll fail to address this or that stream, do correct me whenever you feel the need.
This post is going to be long, so I’ll provide a little guidance here. First, I will summarise where I am now, there may be nuanced differences with the substance of original post, but if there are, I can’t spot them properly (a well-known cognitive limitation: after changing your mind, it’s very difficult to reconstruct your previous beliefs in a faithful way). There certainly is a shift of focus, which I hope is going to help clarify the overall conceptual architecture that I have in mind. After the summary, I will try to discuss the challenges that have been raised, the ones that I would expect to receive, and where disagreements remain unresolved. Finally, I’ll write some conclusive reflections.
Computational Functionalism requires Embodiment.
The whole debate, for me revolves around the question: can computations generate intentionality? Critics of computational functionalism say “No” and take this as a final argument to conclude that computations can’t explain minds. I also answer “No” but reach a weaker conclusion: computations can never be the whole story, we need something else to get the story started (provide a source for intentionality), but computations are the relevant part of how the story unfolds.
The missing ingredient comes from what I call “structures”: some “structures” in particular (both naturally occurring and artificial) exist because they effectively measure some feature of the environment and translate it into a signal, more structure then use, manipulate and re-transmit this signal in organised ways, so that the overall system ends up showing behaviours that are causally connected to what was measured. Thus, I say that such systems (the overall structure) are to be understood as manipulating signals about certain features of the world.
This last sentence pretty much summarises all I have to say: it implies computations (collecting, transmitting, manipulating signals and then generating output). It also implies intentionality: the signals are about something. Finally, it shows that what counts are physical structures that produce, transmit and manipulate signals: without embodiment, nothing can happen at all. I conclude that such structures can use their intrinsic intentionality (as long as their input, transmission & integration structures work, they produce and manipulate signals about something), and build on it, so that some structures can eventually generate meanings and become conscious.
Once intentionality is available (and it is from the start), you get a fundamental ingredient that does something fundamental, which is over an beyond what can be achieved by computations alone.
Say that you find an electric cable, with variable current/voltage that flows in it. You suspect it carries a signal, but as Jochen would point out, without some pre-existing knowledge about the cable, you have no way of figuring out what it is being signalled.
But what precedes brains already embodies the guiding knowledge: the action potentials that travel on axons from sensory periphery to central brain are already about something (as are the intracellular mechanisms that generate them at the receptor level). Touch, temperature, smells, colours, whatever. Their mapping isn’t arbitrary or optional, their intentionality is a quality of the structures that generate them.
Systems that are able to generate meanings and become conscious are, as far as we know (and/or for the time being), biological, so I will now move to animals and human animals in particular. Specifically, each one of us produces internal sensory signals that already are about something, and some of them (proprioception, pain, pleasure, hunger, and many more) are about ourselves.
Critics should say that, for any given functioning body, you can in theory interpret these signals as encoding the list of first division players of whichever sport you’d like, all you need is to design a post-hoc encoding to specify the mapping from signal to signified player – this is equivalent to our electrical cable above: without additional knowledge, there is no way to correctly interpret the signals from a third-party perspective. However, within the structure that contains these signals, they are not about sports, they really are about temperature, smell, vision and so forth: they reliably respond to certain features of the world, in a highly (and imperfect) selective way.
Thus, you (all of us) can find meaningful correlations between signals coming from the world, between the ones that are about yourself, and all combinations thereof. This provides the first spark of meaning (this smells good, I like this panorama, etc). From there, going to consciousness isn’t really that hard, but it all revolves around two premises, which are what I’m trying to discuss here.
- Premise one: intentionality comes with the sensory structure. I hope that much is clear. You change the structure, you change what the signal is about.
- Premise two: once you have a signal about something, the interpretation isn’t arbitrary any more. If you are a third-party, it may be difficult/impossible to establish what a signal is signalling exactly, but in theory, the ways to empirically get closer to the correct answer can exist. However, these ways are entirely contingent: you need to account for the naturally occurring environment where the signal-bearing structure emerged.
If you accept these premises, it follows that:
a) Considering brains, they are in the business of integrating sensory signals to produce behavioural outputs. They can do so, because the system they belong to includes the mapping: signals about touch are just that. Thus, from within, the mapping comes from hard-constraints, in fact, you would expect that these constraints are enough to bootstrap cognition.
b) To do so, highly developed and plastic brains use sensory input to generate models of the world (and more). They compute in the sense that they manipulate, shuffle symbols around, and generate new ones.
c) Because the mapping is intrinsic, the system can generate knowledge about itself and the world around it. “I am hungry”, “I like pizza”, “I’ll have a pizza” become possible, and are subject-relative.
d) thus, when I say “The only facts are epistemological” I actually mean two things (plus one addendum below): (1) they relate to self-knowledge, and (2) they are facts just the same (actually, I’d say they are the only genuine facts that you can find, because of (1)).
Thus, given a system, from a third-party perspective, in theory, we can:
i. Use the premises and conclusion a) to make sensible hypotheses on what the intrinsic mapping/intentionality/aboutness might be (if any).
ii. Use a mix of theories, including information (transmission) theory (Shannon’s) and the concept of abstract computations to describe how the signals are processed: we would be tapping the same source of disambiguation – the structure that produces signals about this but not that.
iii. This will need to closely mirror what the structures in the brain actually do: at each level of interpretational abstraction, we need to keep verifying that our interpretation keeps reflecting how the mechanisms behave (e.g. our abstractions need to have verifiable predictive powers). This can be done (and is normally done) via the standard tools of empirical neuroscience.
iv. If and only if we’ll be able to build solid interpretations (i.e. ones that make reliable predictions) and we’ll be able to cover all the distance between original signals, consciousness and then behaviour, we will have a second map: from the mechanisms as described in third-person terms, to “computations” (i.e. abstractions that describe the mechanisms in parsimonious ways).
Buried within the last passage, there is some hope that, at the same time, we will learn something about the mental, because we have been trying to match, and remain in contact with, the initial aboutness of the input. We have hope that computations can describe what counts of the mechanism we are studying because the mechanisms themselves rely on (exist because of) their intrinsic intentionality. This provides a third meaning to “the only facts are epistemological” (3): we would have a way to learn about otherwise subjective mental states. However, in this “third-party” epistemological route, we are using empirical tools, so, unlike the first-party view, where some knowledge is unquestionable (I think therefore I am, remember?), the results we would get will always be somewhat uncertain.
Thus: yes, there is a fact to be known on whether you are conscious (because it is an epistemological fact, otherwise it would not qualify as fact), but the route I’m proposing to find what this fact is is an empirical route and therefore can only approximate to the absolute truth. This requires to grasp the concept that absolute truths depend on subjective ones. If I feel pain, I’m in pain, this is why a third-party can claim there is an objective matter on the subject of my feeling pain. This me is possible because I am made of real physical stuff, which, among other things, collects signals about the structure it entails and the world outside.
At this point it’s important to note that this whole “interpretation” relies on noting that the initial “aboutness” (generated by sensory structures) is possible because the sensory structures generate a distinction. I see it as a first and usually quite reliable approximation of some property of the external environment: in the example of the simple bacterium, a signal about glucose is generated, and it becomes possible to consider it to be about glucose because, on average, and in the normal conditions where the bacterium is to be found, it will almost always react to glucose alone. Thus, intentionality is founded on a pretence, a useful heuristic, a reliable approximation. This generates the possibility of making further distinctions, and distinctions are a pre-requisite for cognition.
This is also why intentionality can sustain the existence of facts: once the first approximations are done, and note that in this context I could just as well call them “the first abstractions”, conceptual and absolute truths start to appear. 2+2 = 4 becomes possible, as well as “cogito ergo sum” (again).
This more or less concludes my positive case. The rest is about checking if it has any chance of being accepted by more than one person, which leads us to the challenges.
Against Computational Functionalism: the challenges.
To me, the weakest point in all this is premise one. However, to my surprise, my original post got comments like “I don’t know if I’m ready to buy it” and similar, but no one went as far as saying “No, the signal in your fictional bacterium is not about glucose, and in fact it’s not even a signal“. If you think you can construct such a case, please do, because I think it’s the one argument that could convince me that I’m wrong.
Moving on the challenges I have received, Disagreeable Me, in comment #82 remarks:
If your argument depends on […] the only facts about consciousness or intentionality are epistemological facts, then rightly or wrongly that is where Searle and Bishop and Putnam and Chalmers and so on would say your position falls apart, and nearly everyone would agree with them. If youre looking for feedback on where your argument fails to persuade, Id say this is it.
I think he is right in identifying the key disagreement: it’s the reason I’ve re-stated my main argument above, unpacking what I mean with epistemological fact and why I do.
In short: I think the criticism is a category error. Yes there are facts, but they subsist only because they are epistemological. If people search for ontological facts, they can’t find them, because there aren’t any: knowledge requires arbitrary distinctions and at the first level, only allows for useful heuristics. However, once these arbitrary distinctions are done and taken for granted, you can find facts about knowledge. Thus: there are facts about consciousness, because consciousness requires to make the initial arbitrary distinctions. Answering “but in your argument, somewhere, you are assuming some arbitrary distinctions” doesn’t count as criticism: it goes without saying.
This is a problem in practice, however: for people to accept my stance, they need to turn their personal epistemology head over feet, so once more, saying “this is your position, but it won’t convince Searle [Putnam, Chalmers, etc…]” is not criticism to my position. You need to attack my argument for that, otherwise you are implying “Searle is never going to see why your position makes sense”, i.e. you are criticising his position, not mine.
Similarly, the criticism that stems from Dancing with Pixes (DwP: the universal arbitrariness of computations) doesn’t really apply. This is what I think Richard Wein has been trying to demonstrate. If you take computations to be something so abstract that you can “interpret any mechanism to perform any computation” you are saying “this idea of computation is meaningless: it applies to everything and nothing, it does not make any distinction”. Thus, I’ve got to ask: how can we use this definition of computation to make distinctions? In other words, I can’t see how the onus of refuting this argument is in the computationalist camp (I’ve gone back to my contra-scepticism and I once more can’t understand how/why some people take DwP seriously). To me, there is something amiss in the starting definition of computation, as the way it is formulated (forgetting about cardinality for simplicity’s sake) allows drawing no conclusions about anything at all.
If any mechanism can be interpreted to implement any computation, you have to explain me why I spend my time writing software/algorithms. Clearly, I could not be using your idea of computations because I won’t be able to discriminate between different programs (they are all equivalent). But I have a job, and I see the results of my work, so, in the DwP view, something else, not computations, explain what I do for a living. Fine: whatever that something is, it is what I call computations/algorithms. Very few people enjoy spending time in purely semantic arguments, so I’ll leave it to you to invent a way to describe what programming is all about, while accepting the DwP argument. If you’ll be able to produce a coherent description, we can use that in lieu of what I normally refer to computation. The problem should be solved and everyone may save his/her own worldview. It’s also worth noting how all of this echoes the arguments that Chalmers himself uses to respond to the DwP challenge: if we start with perfectly abstract computations, we are shifting all the work on the implementation side.
If you prefer a blunt rebuttal, this should suffice: in my day job I am not paid to design and write functionless abstractions (computations that can be seen everywhere and nowhere). I am ok with my very local description, where computations are what algorithms do: they transform input into outputs in precise and replicable ways. A so and so signal gets in this particular system and comes out transformed in this and that way. Whatever systems show the same behaviour are computationally equivalent. Nothing more to be said, please move on.
Furthermore, what Richard Wein has been trying to show is indeed very relevant: if we accept an idea of computations as arbitrary interpretations of mechanisms, we are saying “computations are exclusively epistemological tools” they are, after all interpretations. Thus, interpretations are explicitly something above and beyond their original subject. It follows that they are abstract and you can’t implement them. Therefore, a computer can’t implement computations: whatever it is that a computer does, can be interpreted as computations, but that’s purely a mental exercise, it has no effect on what the computer does. I’m merely re-stating my argument here, but I think it’s worth repeating. We end up with no way to describe what our computers do: Richard is trying to say, “hang on, this state of affairs in a CPU reliably produces that state” and a preferential way to describe this sort of transitions in computational terms does exist: you will start describing “AND”, “OR”, “XOR” operators and so on. But doing so is not arbitrary.
If I wanted to play the devil’s advocate, I would say: OK, doing so is not arbitrary because we have already arbitrarily assigned some meaning to the input. Voltage arriving through this input is to be interpreted as a 1, no voltage is a 0, same for this other input. On the output side we find:
1,1 -> 1, while 0 is returned for all other cases. Thus this little piece of CPU computes an AND operation. Oh, but now what happens if we invert the map on both the inputs and assume that “no voltage equals 1″?
This is where I find some interest: computers are useful, as John Davey remarked, because we can change the meaning of what they do, that’s why they are versatile.
The main trouble is that computers cant be held to represent anything. And that trouble is precisely the reason they were invented numbers (usually 1s and 0s) are unlimited in the scope of things that they can represent […].
This is true, and important to accept, but does not threaten my position: if I’m right, intentional systems process signals that have fixed interpretations.
Our skin has certain types of receptors that when activated send a signal which is interpreted as “danger! too hot!” (this happens when something starts breaking up the skin cells). If you hold dry ice in your hand, after one or two seconds you will receive that signal (because ice crystals form in your skin and start breaking cells: dry ice is Very Cold!) and it will seem to you that the ice you’re holding has abruptly become very hot (while still receiving the “too cold” signal as well). It’s an odd experience (a dangerous one – be very careful if you wish to try it), which comes in handy: my brain receives the signal and interprets it in the usual way, the signal is about (supposed) too hot conditions, it can misfire, but it still conveys the “Too hot” message. This is what I was trying to say in the original post: within the system, certain interpretations are fixed, we can’t change them at will, they are not arbitrary. We do the same with computers, and find that we can work with them, write one program to play chess, another one for checkers. It’s the mapping in the I/O side that does the trick…
Moving on, Sci pointed to a delightful article from Fodor, which challenges Evolutionary Psychology directly, and marginally disputes the idea that Natural Selection can select for intentionality. I’m afraid that Fodor is fundamentally right in everything he says, but suffers from the same kind of inversion that generates the DwP and the other kind of criticism. I’ll explain the details (but please do read the article: it’s a pleasure you don’t want to deny yourself): the central argument (for us here) is about intentionality and the possibility that it may be “selected for” via natural selection. Fodor says that natural selection selects, but it does not select “for” any specific trait. What traits emerge from selection depends entirely from contingent factors.
On this, I think he is almost entirely right.
However, at a higher level, an important pattern does reliably emerge from blind selection: because of contingency, and thus unpredictability of what will be selected (still without the for), what ultimately tends to accumulate is adaptability per-se. Thus, you can say that natural selection, weakly selects for adaptability. Biologically, this is defensible: no organism relies on a fixed series of well-ordered and tightly constrained events to happen at precise moments in order to survive and reproduce. All living things can survive a range of different conditions and still reproduce. The way they do this is by, surprise! sample the world, and react to it. Therefore: natural selection selects for the seeds of intentionality because intentionality is required to react to changing conditions.
Now, on the subject of intentionality, and to show that natural selection can’t select for intentions, Fodor uses the following:
Jack and Jill
Went up the hill
To fetch a pail of water
Jack fell down
And broke his crown
And thus decreased his fitness.
(I told you it’s delightful!)
His point is that selection can’t act on Jack’s intention of fetching water, but only on the contingent fact that Jack broke his crown. He is right, but miles from our mark. What is selected for is Jack’s ability to be thirsty, he was born with internal sensors that detect lack of water: without them he would have been long dead before reaching the hill. Mechanisms to maintain homeostasis in an ever changing world (within limits) are not optional, they exist because of contingency: their existence is necessary because the world out there changes all the time. Thus: natural selection very reliably selects for one trait: intentionality. Intentionality about what, and how intentionality is instantiated in particular creatures is certainly determined by contingent factors, but it remains that intentionality about something is a general requirement for living things (unless they live in a 100% stable environment, which is made impossible by their very presence).
However, Fodor’s argument works a treat when it’s used to reject some typical Evolutionary Psychology claims such as “Evolution selected for the raping-instinct in human males”, such claims might be pointing into something which isn’t entirely wrong, but are nevertheless indefensible because evolution directly selects for things that are far removed from complex behaviours. Once intentionality of some sort is there, natural selection keeps selecting, and Fodor is right in explaining why there are no general rules on what it selects for (at that level): when we are considering the details, contingency gets the upper hand.
What Fodor somehow manages to ignore is the big distance between raw (philosophical) intentionality (the kind I’m discussing here – AKA aboutness), and fully formed intentions (as desires and similar). We all know the two are connected, but they are not the same: it’s very telling that Fodor’s central argument revolves around the second (Jack’s plan to go and fetch some water), but only mentions the first in very abstract terms. Once again: selection does select for the ability to detect the need for a given resource (when this need isn’t constant) and for the ability to detect the presence/availability of needed resources (again, if their levels aren’t constant). This kind of selection for is (unsurprisingly) very abstract, but it does pinpoint a fundamental quality of selection which is what explains the existence of sensory structures, and thus of intrinsic intentionality. What Fodor says hits the mark on more detailed accounts, but doesn’t even come close to the kind of intentionality I’ve been trying to pin-down.
The challenges that I did not receive.
In all of the above I think one serious criticism is missing: we can accept that a given system collects intentional systems, but how does the systems “know” what these signals are about? So far, I’ve just assumed that some systems do. If we go back to our bacterium, we can safely assume that such a systems knows exactly nothing: it just reacts to the presence of glucose in a very organised way. It follows that some systems use their intrinsic intentionality in different ways: I can modulate my reactions to most stimuli, while the bacterium does not. What’s different? Well, to get a glimpse, we can step up to a more complex organism, and pick one with a proper nervous system, but still simple enough. Aplysia: we know a lot about these slugs, and we know they can be conditioned. They can learn associations between neutral and noxious stimuli, so that after proper training they would react protectively to the neutral stimulus alone.
Computationally there is nothing mysterious (although biologically we still don’t really understand the relevant details): input channel A gets activated and carries inconsequential information, after this, channel B starts signalling something bad and an avoidance output is generated. Given enough repetitions the association is learned, and input from channel A short-cuts to produce the output associated with B. You can easily build a simulation that works on the hypothesis “certain inputs correlate” and reproduces the same functionality. Right: but does our little slug (and our stylised simulation) know anything? In my view, yes and no: trained individuals learn a correlation, so they do know something, but I wouldn’t count it as fully formed knowledge because it is still too tightly bound, it still boils down to automatic and immediate reactions. However, this example already shows how you can move from bare intentionality to learning something that almost counts as knowledge. It would be interesting to keep climbing the complexity scale and see if we can learn how proper knowledge emerges, but I’ll stop here, because the final criticism that I haven’t so far addressed can now be tackled: it’s Searle’s the Chinese room.
To me, the picture I’m trying to build says something about what’s going on with Searle in the room, and I find this something marginally more convincing than all the rebuttals of the Chinese room argument that I know of. The original thought experiment relies on one premise: that it is possible to describe how to process the Chinese input in algorithmic terms, so that a complete set of instructions can be provided. Fine: if this is so, we can build a glorified bacterium, or a computer (a series of mechanisms) to do Searle’s job. The point I can add is that even the abilities of Aplysiae exceed the requirements: Searle in the room doesn’t even need to learn simple associations. Thus, all the Chinese room shows us is that you don’t need a mind to follow a set of static rules. Not news, isn’t it? Our little slugs can do more: they use rules to learn new stuff, associations that are not implicit in the algorithm that drives their behaviour, what is implicit is that correlations exist, and thus learning them can provide benefits.
Note that we can easily design an algorithm that does this, and note that what it does can count as a form of abstraction: instead of a rigid rule, we have a meta-rule. As a result, we have constructed a picture that shows how sensory structures plus computations can account for both intentionality and basic forms of learning; in this picture, the Chinese room task is already surpassed: it’s true that neither Searle nor the whole room truly know Chinese, because the task doesn’t require to know it (see below). What is missing is feedback and memories of the feedback: Searle chucks out answers, which count as output/behaviour, but they don’t produce consequences, and the rules of the game don’t require to keep track neither of the consequences nor of the series of questions.
Follow me if you might: what happens if we add a different rule, and say that the person who feeds in the questions is allowed to feed questions that build on what was answered before? To fulfil this task Searle would need an additional set of rules: he will need instructions to keep a log of what was asked and answered. He would need to recall associations, just like the slugs. Once again, he will be following an algorithm but with an added layer of abstraction. Would the room “know Chinese” then? No, not yet: feedback is still missing. Imagine that the person feeding the questions is there with the aim of conducting a literary examination (they are questions about a particular story) and that whenever the answers don’t conform to a particular critical framework, Searle will get a punishment, when the answers are good he’ll get a reward. Now: can Searle use the set of rules from the original scenario and learn how to “pass the exam”? Perhaps, but can he learn how to avoid the punishments without starting to understand the meanings of the scribbles he produces as output? (You guessed right: I’d answer “No” to the second question)
The thing to note is that the new extended scenario is starting to resemble real life a little more: when human babies are born, we can say that they will need to learn the rules to function in the world, but also that such rules are not fixed/known a-priori. Remember what I was saying about Fodor and the fact that adaptability is selected for? To get really good at the Chinese room extended game you need intentionality, meaning, memory and (self) consciousness: so the question becomes, not knowing anything about literary theory, would it be possible to provide Searle with an algorithm that will allow him to learn how to avoid punishments? We don’t know, so it’s difficult to say whether, after understanding how such an algorithm may work, we would find it more or less intuitive that the whole room (or Searle) will learn Chinese in the process. I guess Peter would maintain that such an algorithm is impossible, in his view, it has to be somewhat anomic.
My take is that to write such an algorithm we would “just” need to continue along the path we have seen so far: we need to move up one more level of abstraction and include rules that imply (assume) the existence of a discrete system (self), defined by the boundaries between input and output. We also need to include the log of the previous question-answer-feedback loop, plus of course, the concepts of desirable and undesirable feedback (anybody is thinking “Metzinger” right now?). With all this in place (assuming it’s possible), I personally would find it much easier to accept that, once it got good at avoiding punishments, the room started understanding Chinese (and some literary theory).
I am happy to admit that this whole answer is complicated and weak, but it does shed some light even if you are not prepared to follow me the whole way: at the start I argue that the original task is not equivalent to “understanding Chinese”, and I hope that what follows clarifies that understanding Chinese requires something more. This is why the intuition the original Chinese room argument produces is so compelling and misleading. Once you imagine something more life-like, the picture starts blurring in interesting ways.
That’s it. I don’t have more to say at this moment.
Short list of the points I’ve made:
- Computations can be considered as 100% abstract, thus they can apply to everything and nothing. As a result, they can’t explain anything. True, but this means that our hypothesis (Computations are 100% abstract) needs revising.
- What we can say is that real mechanisms are needed, because they ground intentionality.
- Thus, once we have the key to guide our interpretation, describing mechanisms as computations can help to figure out what generates a mind.
- To do so, we can start building a path that algorithmically/mechanistically produces more and more flexibility by relying on increasingly abstract assumptions (the possibility to discriminate first, the possibility to learn from correlations next, and then up to learning even more based on the discriminations between self/not-self and desirable/not desirable).
- This helps addressing the Chinese room argument, as it shows why the original scenario isn’t depicting what it claims to depict (understanding Chinese). At the same time this route allows to propose some extensions that start making the idea of conscious mechanisms a bit less counter-intuitive.
- In the process, we are also starting to figure out what knowledge is, which is always nice
I Hope youve enjoyed the journey as much as I did! Please do feel free to rattle my cage even more, I will think some more and try to answer as soon as I can.
Chalmers, D. J. (1996). Does a rock implement every finite-state automaton?. Synthese, 108(3), 309-333.
Chen, S., Cai, D., Pearce, K., Sun, P. Y., Roberts, A. C., & Glanzman, D. L. (2014). Reinstatement of long-term memory following erasure of its behavioral and synaptic expression in Aplysia. Elife, 3, e03896.
Fodor, J. (2008). Against Darwinism. Mind & Language, 23(1), 1-24.
Searle, J. R. (1980). Minds, brains, and programs. Behavioral and brain sciences, 3(03), 417-424.
Dan Dennett famously based his view of consciousness on the intentional stance. According to him the attribution of intentions and other conscious states is a most effective explanatory strategy when applied to human beings, but that doesn’t mean consciousness is a mysterious addition to physics. He compares the intentions we attribute to people with centres of gravity, which also help us work out how things will behave, but are clearly not a new set of real physical entities.
Whether you like that idea or not, it’s clear that the human brain is strongly predisposed towards attributing purposes and personality to things. Now a new study by Spunt, Meyer and Lieberman using FMRI provides evidence that even when the brain is ostensibly not doing anything, it is in effect ready to spot intentions.
This is based on findings that similar regions of the brain are active both in a rest state and when making intentional (but not non-intentional) judgements, and that activity in the pre-frontal cortex of the kind observed when the brain is at rest is also associated with greater ease and efficiency in making intentional attributions.
There’s always some element of doubt about how ambitious we can be in interpreting what FMRI results are telling us, and so far as I can see it’s possible in principle that if we had a more detailed picture than FMRI can provide we might see more significant differences between the rest state and the attribution of intentions; but the researchers cite evidence that supports the view that broad levels of activity are at least a significant indicator of general readiness.
You could say that this tells us less about intentionality and more about the default state of the human mind. Even when at rest, on this showing, the brain is sort of looking out for purposeful events. In a way this supports the idea that the brain is never naturally quiet, and explains why truly emptying the mind for purposes of deep meditation and contemplation might require deliberate preparation and even certain mental disciplines.
So far as consciousness itself is concerned, I think the findings lend more support to the idea that having ‘theory of mind’ is an essential part of having a mind: that is, that being able to understand the probable point of view and state of knowledge of other people is a key part of having full human-style consciousness yourself.
There’s obviously a bit of a danger of circularity there, and I’ve never been sure it’s a danger that Dennett for one escapes. I don’t know how you attribute intentions to people unless you already know what intentions are. The normal expectation would be that I can do that because I have direct knowledge of my own intentions, so all I need to do is hypothesise that someone is thinking the way I would think if I were in their shoes. In Dennett’s theory, me having intentions is really just more attribution (albeit self-attribution), so we need some other account of how it all gets started (apparently the answer is that we assume optimal intentions in the light of assumed goals).
Be that as it may, the idea that consciousness involves attributing conscious states to ourselves is one that has a wider appeal and it may shed a slightly different light on the new findings. It might be that the base activity identified by the study is not so much a readiness to attribute intentions, but a continuous second-order contemplation of our own intentions, and an essential part of normal consciousness. This wouldn’t mean the paper’s conclusions are wrong, but it would suggest that it’s consciousness itself that makes us more ready to attribute intentions.
Hard to test that one because unconscious patients would not make co-operative subjects…
Over at Brains Blog Uriah Kriegel has been doing a series of posts (starting here) on some themes from his book The Varieties of Consciousness, and in particular his identification of six kinds of phenomenology.
I haven’t read the book (yet) and there may be important bits missing from the necessarily brief account given in the blog posts, but it looks very interesting. Kriegel’s starting point is that we probably launch into explaining consciousness too quickly, and would do well to spend a bit more time describing it first. There’s a lot of truth in that; consciousness is an extraordinarily complex and elusive business, yet phenomenology remains in a pretty underdeveloped state. However, in philosophy the borderline between describing and explaining is fuzzy; if you’re describing owls you can rely on your audience knowing about wings and beaks and colouration; in philosophy it may be impossible to describe what you’re getting at without hacking out some basic concepts which can hardly help but be explanatory. With that caveat, it’s a worthy project.
Part of the difficulty of exploring phenomenology may come from the difficulty of reconciling differences in the experiences of different reporters. Introspection, the process of examining our own experience, is irremediably private, and if your conclusions are different from mine, there’s very little we can do about it other than shout at each other. Some have also taken the view that introspection is radically unreliable in any case, a task like trying to watch the back of your own head; the Behaviourists, of course, concluded that it was a waste of time talking about the contents of consciousness at all: a view which hasn’t completely disappeared.
Kriegel defends introspection, albeit in a slightly half-hearted way. He rightly points out that we’ve tacitly relied on it to support all the discoveries and theorising which has been accomplished in recent decades. He accepts that we cannot any longer regard it as infallible, but he’s content if it can be regarded as more likely right than wrong.
With this mild war-cry, we set off on the exploration. There are lots of ways we can analyse consciousness, but what Kriegel sets out to do is find the varieties of phenomenal experience. He’s come up with six, but it’s a tentative haul and he’s not asserting that this is necessarily the full set. The first two phenomenologies, taken as already established, are the perceptual and the algedonic (pleasure/pain); to these Kriegel adds: cognitive phenomenology, “conative” phenomenology (to do with action and intention), the phenomenology of entertaining an idea or a proposition (perhaps we could call it ‘considerative’, though Kriegel doesn’t), and the phenomenology of imagination.
The idea that there is conative phenomenology is a sort of cousin of the idea of an ‘executive quale’ which I have espoused: it means there is something it is like to desire, to decide, and to intend. Kriegel doesn’t spend any real effort on defending the idea that these things have phenomenology at all, though it seems to me (introspectively!) that sometimes they do and sometimes they don’t. What he is mainly concerned to do is establish the distinction between belief and desire. In non-phenomenal terms these two are sort of staples of the study of intentionality: Bel and Des, the old couple. One way of understanding the difference is in terms of ‘direction of fit’, a concept that goes back to J.L. Austin. What this means is that if there’s a discrepancy between your beliefs and the world, then you’d better change your beliefs. If there’s a discrepancy between your desires and the world, you try to change the world (usually: I think Andy Warhol for one suggested that learning to like what was available was a better strategy, thereby unexpectedly falling into a kind of agreement with some religious traditions that value acceptance and submission to the Divine Will).
Kriegel, anyway, takes a different direction, characterising the difference in terms of phenomenal presentation. What we desire is presented to us as good; what we believe is presented as true. This approach opens the way to a distinction between a desire and a decision: a desire is conditional (if circumstances allow, you’ll eat an ice-cream) whereas a decision is categorical (you’re going to eat an ice-cream). This all works quite well and establishes an approach which can handily be applied to other examples; if we find that there’s presentation-as-something different going on we should suspect a unique phenomenology. (Are we perhaps straying here into something explanatory instead of merely descriptive? I don’t think it matters.) I wonder a bit about whether things we desire are presented to us as good. I think I desire some things that don’t seem good at all except in the sense that they seem desirable. That’s not much help, because if we’re reduced to saying that when I desire something it is presented to me as desirable we’re not saying all that much, especially since the idea of presentation is not particularly clarified. I have no doubt that issues like this are explored more fully in the book.
Kriegel moves on to consider the case of emotion: does it have a unique and irreducible phenomenology? If something we love is presented to us as good, then we’re back with the merely conative; and Kriegel doesn’t think presentation as beautiful is going to work either (partly because of negative cases, though I don’t see that as an insoluble probem myself; if we can have algedonia, the combined quality of pain or pleasure we can surely have an aesthetic quality that combines beauty and ugliness). In the end he suspects that emotion is about presentation as important, but he recognises that this could be seen as putting the cart before the horse; perhaps emotion directs our attention to things and what gets our attention seems to be important. Kriegel finds it impossible to decide whether emotion has an independent phenomenology and gives the decision by default in favour of the more parsimonious option, that it is reducible to other phenomenologies.
On that, it may be that taking all emotion together was just too big a bite. It seems quite likely to me that different emotions might have different phenomenologies, and perhaps tackling it that way would yield more positive results.
Anyway, a refreshing look at consciousness.
I finally saw Ex Machina, which everyone has been telling me is the first film about artificial intelligence you can take seriously. Competition in that area is not intense, of course: many films about robots and conscious computers are either deliberately absurd or treat the robot as simply another kind of monster. Even the ones that cast the robots as characters in a serious drama are essentially uninterested in their special nature and use them as another kind of human, or at best to make points about humanity. But yes: this one has a pretty good grasp of the issues about machine consciousness and even presents some of them quite well, up to and including Mary the Colour Scientist. (Spoilers follow.)
If you haven’t seen it (and I do recommend it), the core of the story is a series of conversations between Caleb, a bright but naive young coder, and Ava, a very female robot. Caleb has been told by Nathan, Ava’s billionaire genius creator, that these conversations are a sort of variant Turing Test. Of course in the original test the AI was a distant box of electronics: here she’s a very present and superficially accurate facsimile of a woman. (What Nathan has achieved with her brain is arguably overshadowed by the incredible engineering feat of the rest of her body. Her limbs achieve wonderful fluidity and power of movement, yet they are transparent and we can see that it’s all achieved with something not much bigger than a large electric cable. Her innards are so economical there’s room inside for elegant empty spaces and decorative lights. At one point Nathan is inevitably likened to God, but on anthropomorph engineering design he seems to leave the old man way behind.)
Why does she have gender? Caleb asks, and is told that without sex humans would never have evolved consciousness; it’s a key motive, and hell, it’s fun. In story terms making Ava female perhaps alludes to the origin of the Turing Test in the Imitation Game, which was a rather camp pastime about pretending to be female played by Turing and his friends. There are many echoes and archetypes in the film; Bluebeard, Pygmalion, Eros and Psyche to name but three; all of these require that Ava be female. If I were a Jungian I’d make something of that.
There’s another overt plot reason, though; this isn’t really a test to determine whether Ava is conscious, it’s about whether she can seduce Caleb into helping her escape. Caleb is a naive girl-friendless orphan; she has been designed not just as a female but as a match for Caleb’s preferred porn models (as revealed in the search engine data Nathan uses as his personal research facility – he designed the search engine after all). What a refined young Caleb must be if his choice of porn revolves around girls with attractive faces (on second thoughts, let’s not go there).
We might suspect that this test is not really telling us about Ava, but about Caleb. That, however, is arguably true of the original Turing Test too. No output from the machine can prove consciousness; the most brilliant ones might be the result of clever tricks and good luck. Equally, no output can prove the absence of consciousness. I’ve thought of entering the Loebner prize with Swearbot, which merely replies to all input with “Shut the fuck up” – this vividly resembles a human being of my acquaintance.
There is no doubt that the human brain is heavily biased in favour of recognising things as human. We see faces in random patterns and on machines; we talk to our cars and attribute attitudes to plants. No doubt this predisposition made sense when human beings were evolving. Back then, the chances of coming across anything that resembled a human being without it being one were low, and given that an unrecognised human might be a deadly foe or a rare mating opportunity the penalties for missing a real one far outweighed those for jumping at shadows or funny-shaped trees now and then.
Given all that, setting yourself the task of getting a lonely young human male romantically interested in something not strictly human is perhaps setting the bar a bit low. Naked shop-window dummies have pulled off this feat. If I did some reprogramming so that the standard utterance was a little dumb-blonde laugh followed by “Let’s have fun!” I think even Swearbot would be in with a chance.
I think the truth is that to have any confidence about an entity being conscious, we really need to know something about how it works. For human beings the necessary minimum is supplied by the fact that other people are constituted much the same way as I am and had similar origins, so even though I don’t know how I work, it’s reasonable to assume that they are similar. We can’t generally have that confidence with a machine, so we really need to know both roughly how it works and – bit of a stumper this – how consciousness works.
Ex Machina doesn’t have any real answers on this, and indeed doesn’t really seek to go much beyond the ground that’s already been explored. To expect more would probably be quite unreasonable; it means though, that things are necessarily left rather ambiguous.
It’s a shame in a way that Ava resembles a real woman so strongly. She wants to be free (why would an AI care, and why wouldn’t it fear the outside world as much as desire it?), she resents her powerlessness; she plans sensibly and even manipulatively and carries on quite normal conversations. I think there is some promising scope for a writer in the oddities that a genuinely conscious AI’s assumptions and reasoning would surely betray, but it’s rarely exploited; to be fair Ex Machina has the odd shot, notably Ava’s wish to visit a busy traffic intersection, which she conjectures would be particularly interesting; but mostly she talks like a clever woman in a cell. (Actually too clever: in that respect not too human).
At the end I was left still in doubt. Was the take-away that we’d better start thinking about treating AIs with the decent respect due to a conscious being? Or was it that we need to be wary of being taken in by robots that seem human, and even sexy, but in truth are are dark and dead inside?
Not so long ago I’ve enthusiastically participated in the first phases of the discussion below Peter’s post on “Pointing”. The discussion rapidly descended in the fearsome depths of the significance of computation. In the process, more than one commentator directly and effectively challenged my computationalist stance. This post is my attempt to clarify my position, written with a sense of gratitude to all: thanks to all for challenging my assumptions so effectively, and to Peter for sparking the discussion and hosting my reply.
This lengthy post will proceed as follows: first, I’ll try to summarise the challenge that is being forcefully proposed. At the same time, I’ll explain why I think it has to be answered. The second stage will be my attempt to reformulate the problem, taking as a template a very practical case that might be uncontroversial. With the necessary scaffolding in place, I hope that building my answer will become almost a formality. However, the subject is hard, so wish me luck because I’ll need plenty.
The challenge: in the discussion, Jochen and Charles Wolverton showed that “computations” are arbitrary interpretations of physical phenomena. Because Turing machines are pure abstractions, it is always possible to arbitrarily define a mapping between the evolving states of any physical object and abstract computations. Therefore asking, “what does this system compute?” does not admit a single answer, the answer can be anything and nothing. In terms of one of our main explananda: “how do brains generate meanings?” the claim is that answering “by performing some computation” is therefore always going to be an incomplete answer. The reason is that computations are abstract: physical processes acquire computational meaning only when we (intentional beings) arbitrarily interpret these processes in terms of computation. From this point of view, it becomes impossible to say that computations within the brain generate the meanings that our minds deal with, because this view requires meanings to be a matter of interpretation. Once one accepts this point of view, meanings always pre-exist as an interpretation map held by an observer. Therefore, “just” computations, can only trade pre-existing (and externally defined!) meanings and it would seem that generating new meanings from scratch entails an infinite regression.
To me, this is nothing but another transformation of the hard problem, the philosophical kernel that one needs to penetrate in order to understand how to interpret the mechanisms that we can study scientifically. It is also one of the most beautifully recursive problem that I can envisage: the challenge is to generate an interpretative map that can be used to show how interpretative maps can be generated from scratch, but this seems impossible, because apparently you can only generate a new map if you can ground it on a pre-existing map. Thus, the question becomes: how do you generate the first map, the first seed of meaning, a fixed reference point, which gets the recursive process started?
In the process of spelling out his criticism, Jochen gave the famous example of a stone. Because the internal state of the stone changes all the time, for any given computation, we can create an ad-hoc map that specifies the correspondence of a series of computational steps with the sequence of internal steps of our stone. Thus, we can show that the stone computes whatever we want, and therefore, if we had a computational reduction of a mind/brain, we could say that the same mind exists within every stone. Consequently, computationalism can either require some very odd form of panpsychism or be utterly useless: it can’t help to discriminate between what can generate a mind and what can’t. I am not going to embrace panpsychism, so I am left with the only option of biting the bullet and show how this kind of criticism can be addressed.
Without digressing too much, I hope that the above leaves no doubt about where I stand: first, I think this critique of computational explanations of the (expected) mind/brain equivalence is serious, it needs an answer. Furthermore, I also think that answering it convincingly would count as significant progress, even a breakthrough, if we take ‘convincingly’ to stand for ‘capable of generating consensus’. Dissolving this apparently unsolvable conundrum is equivalent to showing why a mechanism can generate a mind, I don’t know if there is a bigger prize in this game.
I’ll start from my day job, I write software for a living. What I do is write instructions that would make a computer reliably execute a given sequence of computations, and produce the desired results. It follows that I can, somehow, know for sure what computations are going to be performed: if I couldn’t, writing my little programs would be vain. Thus, there must be something different between our ordinary computers and any given stone. The obvious difference is that computers are engineered, they have a very organised structure and behaviour, specifically because this makes programming them feasible. However, in theory, it would be possible to produce massively complicated input/output systems to substitute the relevant parts (CPU, RAM, long-term memory) of a computer with a stone, we don’t do this because it is practically far too complicated, not because it is theoretically impossible. Thus, the difference isn’t in the regular structure and easily predictable behaviour of the Von Neumann/Harvard and derived architectures. I think that the most notable differences are two:
- When we use a computer, we already have agreed upon the correct way to interpret its output. More specifically, all the programs that are written assume such a mapping, and would produce outputs that conform to it. If a given program will be used by humans (this isn’t always the case!) the programmer will make sure that the results will be intelligible to us. Similarly, the mapping between the computer states and their computational meaning is also fixed (so fixed and agreed in advance, that I don’t even need to know how it works, in practice).
- In turn, because the mapping isn’t arbitrary, also the input/output transformations follow predefined and discrete sets of rules. Thus, you can plug different monitors and keyboards, and expect them to work in similar ways.
For both differences, it’s a matter of having a fixed map (we can for simplicity collapse the maps from 1 & 2 into a single one). Once our map is defined and agreed upon, we can solve the stone problem and say “computer X is running software A, computer Y is running software B” and expect everyone to agree. The arbitrariness of the map becomes irrelevant because in this case the map itself has been designed/engineered and agreed from the start.
This isn’t trivial, because it becomes enlightening when we propose the hypothesis that brains can be modelled as computers. Note my wording: I am not saying “brains are computers”, I talk about “modelled” because the aim is to understand how brains work, it’s an epistemological quest. We are not asking “what brains/minds are”; in fact, I’ll do all I can to steer away from ontology altogether.
Right, if we assume that brains can be modelled as computers, it follows that it should be possible to compose a single map that would allow us to interpret brain mechanisms in terms of computations. Paired with a perfect brain scanner (a contraption that can report all of the brain states that are required to do the mapping) such a map would allow us to say without doubt “this brain is computing this and that”. As a result, with relatively little additional effort, it should become possible to read the corresponding brain. From this point of view, the fact that there is an infinite number of possible maps, but only one is “the right” one, means that the problem is not about arbitrariness (as it seemed for the stone). The problem is entirely different, it is about finding the correct map, the one that is able to reliably discern what the scanned mind is thinking about. This is why in the original discussion I’ve said the arbitrariness of the mapping is the best argument for a computational theory of the mind. It ensures the search space for the map is big enough to give us hope that such a map does exist. Note also that all of the above is nothing new, it is just stating explicitly the assumptions that underline all of neuroscience; if there are some exceptions, they would be considered very unorthodox.
However, this where I think that the subject becomes interesting. All of the above has left out the hard side of the quest, I haven’t even tried to address the problem of how computations can generate a “meaningful map” on its own. To tackle this mini-hard problem, we need to go back to where we started and recollect how I’ve described the core of the “anti-computalism” stance. Taking about brain/mechanisms, I’ve asked: how [does the brain] generate the first map, the first seed of meaning, a fixed reference point, which gets the recursive process started? Along the way, I’ve claimed that it is reasonable to expect that a different but important map can be found, the one that describes (among many other things) how to translate brain events into mind events (thoughts, memories, desires, etc.). Therefore, one has to admit that this second map (our computational interpretation) would have to contain, at least implicitly, the answer on the fixed reference point. How is this possible? Note that I’ve strategically posed the question in my own terms, and mentioned the need for a fixed reference point. You may want to recall the “I-token” construct of Retinoid Theory, but in general, one can easily point out that the reference point is provided by the physical system itself. We have, ex-hypothesis, a system that collects “measurements” from the environment (sensory stimuli), processes them, and produces output (behaviour); this output is usually appropriate to preserve the system integrity (and reproduce, but that’s another story). Fine, such a system IS a fixed reference point. The integrity that justifies the whole existence of the system IS precisely what is fixed – all the stimuli it collects are relative to the system itself. As long as the system is intact enough to function, it can count as a fixed reference point; with a fixed reference, meanings become possible because reliable relations can be identified, and if they can, then they can be grouped together and produce more comprehensive “interpretative” maps. This is the main reason why I like Peter’s Haecceity: it’s the “thisness” of a particular computational system that actually seeds the answer of the hard side of the question.
Note also that all of the above captures the differences I’ve spelled out between a standard computer and a common stone. It’s the specific physicality of the computer that ultimately distinguishes it from a stone: in this case, we (humans) have defined a map (designing it from scratch with manageability in mind) and then used the map to produce a physical structure that will behave accordingly. In the case of brains/minds, we need to proceed in the opposite direction: given a structure and its dynamic properties, we want to define a map that is indeed intelligible.
- The computational metaphor should be able to capture the mechanisms of the brain and thus describe the (supposed) equivalence between brain events and mind events.
- Such description would count as a weak explanation as it spells out a list of “what” but doesn’t even try to produce a conclusive “why”.
- However, just expecting such mapping to be possible already suggests where to find the “why” (or provides it, if you feel charitable). If such mapping will prove to be possible, it follows that to be conscious, an entity needs to be physical. Its physicality is the source of the ability of generating its own, subjective meanings.
- This in turns reaffirms why our initial problem, posed by the unbounded arbitrariness of computational explanations, does not apply. The computational metaphor is a way to describe (catalogue) a bunch of physical processes, it spells out the “what” but is mute on the “why”. The theoretical nature of computation is the reason why it is useful, but also points to the missing element: the physical side.
- If such a map will turn out to be impossible, the most likely explanation is that there is no equivalence between brain and mind events.
Finally, you may claim that all these conclusions are themselves weak. Even if the problematic step of introducing Haecceity/physicality, as the requirement to bootstrap meaning, is accepted, the explanation we gain is still partial. This is true, but entails the mystery of reality (again, following Peter): because cognition can only generate and use interpretative maps (or translation rules), it “just” shuffles symbols around, it cannot, in no way or form ultimately explain why the physical world exists (or what exactly the physical world is, this is why I steered away from ontology!). Because all knowledge is symbolic, some aspect of reality always has to remain unaccounted and unexplained. Therefore, all of the above can still legitimately feel unsatisfactory: it does not explain existence. But hey, it does talk about subjectivity and meaning (and by extension, intentionality), so it does count as (hypothetical) progress to me.
Now please disagree and make me think some more!
Bernardo Kastrup has some marvellous invective against AI engineers in this piece…
The computer engineer’s dream of birthing a conscious child into the world without the messiness and fragility of life is an infantile delusion; a confused, partial, distorted projection of archetypal images and drives. It is the expression of the male’s hidden aspiration for the female’s divine power of creation. It represents a confused attempt to transcend the deep-seated fear of one’s own nature as a living, breathing entity condemned to death from birth. It embodies a misguided and utterly useless search for the eternal, motivated only by one’s amnesia of one’s own true nature. The fable of artificial consciousness is the imaginary band-aid sought to cover the engineer’s wound of ignorance.
I have been this engineer.
I think it’s untrue, but you don’t have to share the sentiment to appreciate the splendid rhetoric.
Kastrup distinguishes intelligence, which is a legitimate matter of inputs, outputs and the functions that connect them, from consciousness, the true what-it-is likeness of subjectivity. In essence he just doesn’t see how setting up functions in a machine can ever touch the latter.
Not that Kastrup has a closed mind, he speaks approvingly of Pentti Haikonen’s proposed architecture; he just doesn’t think it works. As Kastrup sees it Haikonen’s network merely gathers together sparks of consciousness: it then does a plausible job of bringing them together to form more complex kinds of cognition, but in Kastrup’s eyes it assumes that consciousness is there to be gathered in the first place: that it exists out there in tiny parcels amendable to this kind of treatment. There is in fact, he thinks, absolutely no reason to think that this kind of panpsychism is true: no reason to think that rocks or drops of water have any kind of conscious experience at all.
I don’t know whether that is the right way to construe Haikonen’s project (I doubt whether gathering experiential sparks is exactly what Haikonen supposed he was about). Interestingly, though Kastrup is against the normal kind of panpsychism (if the concept of ‘normal panpsychism’ is admissible), his own view is essentially a more unusual variety.
Kastrup considers that we’re dealing with two aspects here; internal and external; our minds have both; the external is objective, the internal represents subjectivity. Why wouldn’t the world also have these two aspects? (Actually it’s hard to say why anything should have them, and we may suspect that by taking it as a given we’re in danger of smuggling half the mystery out of the problem, but let that pass.) Kastrup takes it as natural to conclude that the world as a whole must indeed have the two aspects (I think at this point he may have inadvertently ‘proved’ the existence of God in the form of a conscious cosmos, which is regrettable, but again let’s go with it for now); but not parts of the world. The brain, we know, has experience, but the groups of neurons that make it up do not (do we actually know that?); it follows that while the world as a whole has an internal aspect, objects or entities within it generally do not.
Yet of course, the brain manages to have two aspects, which must surely be something to do with the structure of the brain? May we not suspect that whatever it is that allows the brain to have an internal aspect, a machine could in principle have it too? I don’t think Kastrup engages effectively with this objection; his view seems to be that metabolism is essential, though why that should be, and why machines can’t have some form of metabolism, we don’t know.
The argument, then, doesn’t seem convincing, but it must be granted that Kastrup has an original and striking vision: our consciousnesses, he suggests, are essentially like the ‘alters’ of Dissociative Identity Disorder, better known as Multiple Personality, in which several different people seem to inhabit a single human being. We are, he says, like the accidental alternate identities of the Universe (again, I think you could say, of God, though Kastrup clearly doesn’t want to).
As with Kastrup’s condemnation of AI engineering, I don’t think at all that he is right, but it is a great idea. It is probable that in his book-length treatments of these ideas Kastrup makes a stronger case than I have given him credit for above, but I do in any case admire the originality of his thinking, and the clarity and force with which he expresses it.
Last time I suggested that qualia – the subjective aspect of experiences that gives them their what-it-is-like quality – are just the particularity, or haecceity, of real experiences. There is something it is like to see that red because you’re really seeing it; you’re not just understanding the theory, which is a cognitive state that doesn’t have any particular phenomenal nature. So we could say qualia are just the reality of experience. No mystery about it after all.
Except of course there is a mystery – what is reality? There’s something oddly arbitrary about reality; some things are real, others are not. That cake on the table in front of me; it could be real as far as you know; or it could indeed be that the cake is a lie. The number 47, though, is quite different; you don’t need to check the table or any location; you don’t need to look for an example, or count to fifty; it couldn’t have been the case that there was no number 47. Things that are real in the sense we need for haecceity seem to depend on events for their reality. I will borrow some terminology from Meinong and call that dependent or contingent kind of reality existence, while what the number 47 has got is subsistence.
What is existence, then? Things that exist depend on events, I suggested; if I made a cake and put it in the table, it exists; if no-one did that, it doesn’t. Real things are part of a matrix of cause and effect, a matrix we could call history. Everything real has to have causes and effects. We can prove that perhaps, by considering the cake’s continuing existence. It exists now because it existed a moment ago; if it had no causal effects, it wouldn’t be able to cause its own future reality, and it wouldn’t be here. If it wasn’t here, then it couldn’t have had preceding causes, so it didn’t exist in the past either. Ergo, things without causal effects don’t exist.
Now that’s interesting because of course, one of the difficult things about qualia is that they apparently can’t have causal effects. If so, I seem to have accidentally proved that they don’t exist! I think things get unavoidably complex here. What I think is going on is that qualia in general, the having of a subjective side, is bestowed on things by being real, and that reality means causal efficacy. However, particular qualia are determined by the objective physical aspects of things; and it’s those that give specific causal powers. It looks to us as if qualia have no causal effects because all the particular causal powers have been accounted for in the objective physical account. There seems to be no role for qualia. What we miss is that without reality nothing has causal powers at all.
Let’s digress slightly to consider yet again my zombie twin. He’s exactly like me, except that he has no qualia, and that is supposed to show that qualia are over and above the account given by physics. Now according to me that is actually not possible, because if my zombie twin is real, and physically just the same, he must end up with the same qualia. However, if we doubt this possibility, David Chalmers and others invite us at least to accept that he is conceivable. Now we might feel that whether we can or can’t conceive of a thing is a poor indicator of anything, but leaving that aside I think the invitation to consider the zombie twin’s conceivability draws us towards thinking of a conceptual twin rather than a real one. Conceptual twins – imaginary, counterfactual, or non-existent ones – merely subsist; they are not real and so the issue of qualia does not arise. The fact that imaginary twins lack qualia doesn’t prove what it was meant to; properly understood it just shows that qualia are an aspect of real experience.
Anyway, are we comfortable with the idea of reality? Not really, because the buzzing complexity and arbitrariness of real things seems to demand an explanation. If I’m right about all real things necessarily being part of a causal matrix, they are in the end all part of one vast entity whose curious firm should somehow be explicable.
Alas, it isn’t. We have two ways of explaining things. One is pure reason: we might be able to deduce the real world from first principles and show that it is logically necessary. Unfortunately pure reason alone is very bad at giving us details of reality; it deals only with Platonic, theoretical entities which subsist but do not exist. To tell us anything about reality it must at least be given a few real facts to work on; but when we’re trying to account for reality as a whole that’s just what we can’t provide.
The other kind of explanation we can give is empirical; we can research reality itself scientifically and draw conclusions. But empirical explanations operate only within the causal matrix; they explain one state of affairs in terms of another, usually earlier one. It’s not possible to account for reality itself this way.
It looks then, as if reality is doomed to remain at least somewhat mysterious, unless we somehow find a third way, neither empirical nor rational.
A rather downbeat note to end on, but sincere thanks to all those who have helped make the discussion so interesting so far…