Tag Archives: Turing

Ex Machina

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Ava2I 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?

Why no AGI?

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AGIAn interesting piece in Aeon by David Deutsch. There was a shorter version in the Guardian, but it just goes to show how even reasonably intelligent editing can mess up a piece. There were several bits in the Guardian version where I was thinking to myself: ooh, he’s missed the point a bit there, he doesn’t really get that: but on reading the full version I found those very points were ones he actually understood very well. In fact he talks a lot of sense and has some real insights.

Not that everything is perfect. Deutsch quite reasonably says that AGI, artificial general intelligence, machines that think like people, must surely be possible. We could establish that by merely pointing out that if the brain does it, then it seems natural that a machine must be able to do it: but Deutsch invokes the universality of computation, something he says he proved in the 1980s. I can’t claim to understand all this in great detail, but I think what he proved was the universality in principle of quantum computation: but the notion of computation used was avowedly broader than Turing computation. So it’s odd that he goes on to credit Babbage with discovering the idea, as a conjecture, and Turing with fully understanding it. He says of Turing:

He concluded that a computer program whose repertoire included all the distinctive attributes of the human brain — feelings, free will, consciousness and all — could be written.

That seems too sweeping to me: it’s not unlikely that Turing did believe those things, but they go far beyond his rather cautious published claims, something we were sort of talking about last time.

I’m not sure I fully grasp what people mean when they talk about the universality of computation. It seems to be that they mean any given physical state of affairs can be adequately reproduced, or at any rate emulated to any required degree of fidelity, by computational processes. This is probably true: what it perhaps overlooks is that for many commonplace entities there is no satisfactory physical description. I’m not talking about esoteric items here: think of a vehicle, or to be Wittgensteinian, a game. Being able to specify things in fine detail, down to the last atom, is simply no use in either case. There’s no set of descriptions of atom placement that defines all possible vehicles (virtually anything can be a vehicle) and certainly none for all possible games, which given the fogginess of the idea, could easily correspond with any physical state of affairs. These items are defined on a different level of description, in particular one where purposes and meanings exist and are relevant.  So unless I’ve misunderstood, the claimed universality is not as universal as we might have thought.

However, Deutsch goes on to suggest, and quite rightly, I think, that what programmed AIs currently lack is a capacity for creative thought. Endowing them with this, he thinks, will require a philosophical breakthrough. At the moment he believes we still tend to believe that new insights come from induction; whereas ever since Hume there has been a problem over induction, and no-one knows how to write an algorithm which can produce genuine and reliable new inductions.

Deutsch unexpectedly believes that Popperian epistemology has the solution, but has been overlooked. Popper, of course, took the view that scientific method was not about proving a theory but about failing to disprove one: so long as your hypotheses withstood all attempts to prove them false (and so long as they were not cast in cheating ways that made them unfalsifiable) you were entitled to hang on to them.

Maybe this helps to defer the reckoning so far as induction is concerned: it sort of kicks the can down the road indefinitely. The problem, I think, is that the Popperian still has to be able to identify which hypotheses to adopt in the first place; there’s a very large if not infinite choice of possible ones for any given set of circumstances.

I think the answer is recognition: I think recognition is the basic faculty underlying nearly all of human thought. We just recognise that certain inductions, and certain events are that might be cases of cause and effect are sound examples: and our creative thought is very largely powered by recognising aspects of the world we hadn’t spotted before.

The snag is, in my view, that recognition is unformalisable and anomic – lacking in rules. I have a kind of proof of this. In order to apply rules, we have to be able to identify the entities to which the rules should be applied. This identification is a matter of recognising the entities. But recognition cannot itself be based on rules, because that would then require us to identify the entities to which those rules applied – and we’d be caught in a in a vicious circle.

It seems to follow that if no rules can be given for recognition, no algorithm can be constructed either, and so one of the basic elements of thought is just not susceptible to computation. Whether quantum computation is better at this sort of thing than Turing computation is a question I’m not competent to judge, but I’d be surprised if the idea of rule-free algorithms could be shown to make sense for any conception of computation.

So that might be why AGI has not come along very quickly. Deutsch may be right that we need a philosophical breakthrough, although one has to have doubts about whether the philosophers look likely to supply it: perhaps it might be one of those things where the practicalities come first and then the high theory is gradually constructed after the fact. At any rate Deutsch’s piece is a very interesting one, and I think many of his points are good. Perhaps if there were a book-length version I’d find that I actually agree with him completely…

Are robots people or people robots?

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boilerplateI must admit I generally think of the argument over human-style artificial intelligence as a two-sided fight. There are those who think it’s possible, and those who think it isn’t. But a chat I had recently made it clear that there are really more differences than that, in particular among those who believe we shall one day have robot chums.

The key difference I have in mind is over whether there really is consciousness at all, or at least whether there’s anything special about it.

One school of thought says that there is indeed a special faculty of consciousness; but eventually machines of sufficient complexity will have it too. We may not yet have all the details of how this thing works; maybe we even need some special new secret. But one thing is perfectly clear; there’s no magic involved, nothing outside the normal physical account, and in fact nothing that isn’t ultimately computable. One day we will be able to build into a machine all the relevant qualities of a human mind. Perhaps we’ll do it by producing an actual direct simulation of a human brain, perhaps not; the point is, when we switch on that ultimate robot, it will have feelings and qualia, it will have moral rights and duties, and it will have the same perception of itself as a real existing personality, that we do.

The second school of thought agrees that we shall be able to produce a robot that looks and behaves exactly like a human being. But that robot will not have qualia or feelings or free will or any of the rest of it, because in reality human beings don’t have them either! That’s one of the truths about ourselves that has been helpfully revealed by the progress of AI: all those things are delusions and always have been. Our feelings that we have a real self, that there is phenomenal experience, and that somehow we have a special kind of agency, those things are just complicated by-products of the way we’re organised.

Of course we could split the sceptics too, between those who think that consciousness requires a special spiritual explanation, or is inexplicable altogether, and those who think it is a natural feature of the world, just not computational or not explained by any properties of the physical world known so far. There is clearly some scope for discussion between the former kind of believer and the latter kind of sceptic because they both think that consciousness is a real and interesting feature of the world that needs more explanation, though they differ in their assumptions about how that will turn out. Although there’s less scope for discussion, there’s also some common ground between the two other groups because both basically believe that the only kind of discussion worth having about consciousness is one that clarifies the reasons it should be taken off the table (whether because it’s too much for the human mind or because it isn’t worthy of intelligent consideration).

Clearly it’s possible to take different views on particular issues. Dennett, for example, thinks qualia are just nonsense and the best possible thing would be to stop even talking about them, while he thinks the ability of human beings to deal with the Frame Problem is a real and interesting ability that robots don’t have but could and will once it’s clarified sufficiently.

I find it interesting to speculate about which camp Alan Turing would have joined; did he think that humans had a special capacity which computers could one day share, or did he think that the vaunted consciousness of humans turned out to be nothing more than the mechanical computational abilities of his machines? It’s not altogether clear, but I suspect he was of the latter school of thought. He notes that the specialness of human beings has never really been proved; and a disbelief in the specialness of consciousness might help explain his caginess about answering the question “can machines think?”. He preferred to put the question aside: perhaps that was because he would have preferred to answer; yes, machines can think, but only so long as you realise that ‘thinking’ is not the magic nonsense you take it to be…