The Infinite Monkey Cage - Are We Living in a Simulation?

Episode Date: July 31, 2017

Are we living in a simulation?Elon Musk thinks we definitely could be, and it seems he is not alone. The idea that we might simply be products of an advanced post-human civilisation, that are simply running a simulation of our universe and everything it contains, has taken hold over the last few years. Brian Cox and Robin Ince are joined on stage by comedian Phill Jupitus, Philosopher Professor Nick Bostrom and Neuroscientist Professor Anil Seth to ask what the chances are that are living in some Matrix like, simulated world and more importantly, how would we ever know?Producer: Alexandra Feachem.

In our new podcast, Nature Answers, rural stories from a changing planet, we are traveling with you to Uganda and Ghana to meet the people on the front lines of climate change. We will share stories of how they are thriving using lessons learned from nature. And good news, it is working. Learn more by listening to Nature Answers wherever you get your podcasts. This is the BBC. Picture a physicist called Brian Cox, a human physicist with human hopes, human dreams, human hair. Maybe not actually human hair, it might be extraterrestrial hair. But just a normal human, or so he thinks.

Because today is the day that this human finds out that he may be a coder's dream, just a simulation in a simulated world. But where could you find this out? In only one place, the Twilight Monkey Cage. Hello, I'm a simulation of Robin Ince. And I'm a simulation of Brian Cox. Actually, I suppose I could be a simulation of Robin Ince as well,

which is worrying, isn't it? How does that work out? I don't want to be you. I like being bald and old and weird looking. So much better than being pretty. I mean, imagine when you lose your looks. That's the end for you. Whereas me, that's never... I've never been employed, but we need someone with braces who's bald and looks old.

For you, Jim Al-Khalil, you'll get all your work once you're both bald. Anyway, so today's show, I suppose in some ways the good thing about it is I've been an atheist for quite a few years, and the worst thing about being an atheist is you lose a greater power to blame for everything that goes wrong. You don't have those moments, oh, God, why have you done this to me?

That's all gone, so you just have to look in the mirror and go, it's your fault again but fortunately thanks to philosophy physics and possibly a little bit elon musk we have something to take the blame rather than zeus odin or yahweh it may be a kid with a power to code and an ability to build artificial worlds so in the words of Keanu Reeves, Woo! On today's Monkey Cage, we are asking, are we living in a simulation? Is your flesh and mind just information, a series of bits in the supercomputers of an advanced civilisation? Are we the product of a greater intelligence? So, to find out whether we are code, reality, or reality that is code, we're joined by three people who may be real or may be code or may be both.

We're going to find that out. Perhaps the very fact that this simulation has been run for the last 13.7 billion years may merely be because it was meant to lead up to this episode of The Infinite Monkey Cage and after this, existence is null and void, so enjoy the last 30 minutes of your life. And our guests are... Nick Bostrom. I'm a professor at Oxford University where I run the Future of Humanity Institute. And my favourite artificial world is maybe London.

Hi, I'm Daniel Seth. I'm a professor of neuroscience at the University of Sussex where I co-direct the Sackler Centre for Consciousness Science. And my favourite artificially created world is Springfield from The Simpsons. Professor of Neuroscience at the University of Sussex, where I co-direct the Sackler Centre for Consciousness Science. And my favourite artificially created world is Springfield from The Simpsons. I'm Phil Jupitus, Professor of Advanced Whimsy at the University of Canby Island. And my favourite imagined world is the University of Canby Island.

And this is our panel. Thank you. the University of Canvey Island. And this is our panel. Nick, let's start with you. When we talk about the idea of a simulated world, a simulated universe, I mean, Elon Musk famously said that he believed there was only a one in a billion chance that this wasn't a simulated world.

What is meant by a simulated world? So what I mean in the context of the simulation argument is a literal simulation that is some advanced civilization builds some big computer and then running on that computer some big simulation of a virtual environment and also of brains simulated to a sufficient level of detail that these simulated brains are conscious. And so the simulation hypothesis is the hypothesis that we are literally living inside a computer designed by some advanced civilisation.

And it sounds like a remarkable science fiction claim, but I know you wrote a paper, a famous paper in 2003, and you said that logically one of three things is true. And the first one was the human species is very likely to go extinct before reaching a post-human stage. Number two, a post-human civilisation is extremely unlikely to run simulations of their history. Or three, we are living in a simulation. So could you just step through why, and I know

you think, and many people think, that the most likely of those three things is three? Well, I haven't claimed that, but I do think that this tripartite disjunction, that it's true that at least one of these three holds. So that's the simulation argument. So what it intuitively says is, suppose for the sake of the argument, that the first possibility is not true. So that means some non-negligible fraction of civilizations at our current stage do eventually reach technological maturity. And suppose also that the second possibility does not obtain.

So that means some non-negligible fraction of these technologically mature civilizations are still interested, even at that stage of maturity, in dedicating some non-trivial fraction of their compute resources to running ancestor simulations. Then, I argue that because we can estimate the amounts of computing power available to a mature civilization, and we can also estimate how much it would take to simulate the human brain, or for that matter, seven billion human brains, there would be many, many more simulated civilizations like ours living in these ancestor simulations than there would be original versions of us. So each post-human civilization could simulate billions and billions and billions of runs of all of human history,

even by dedicating just like one minute of one planet's size of compute to this purpose. So in other words, if you reject the first two possibilities, it seems you are then compelled to accept the third one, which is that we are in a computer simulation. So the simulation argument doesn't tell you which one. It just says that at least one of these has to be true.

And the argument is essentially statistically, if you accept that it's possible to run these simulations and civilisations do, then there are just so many more of those simulated civilizations than real simulations. If you assume that there are many, many more simulations of worlds like this than there are original histories that are non-simulated,

where almost all experiences of the types that we are having are had by simulated people, then conditional on that, we should think we are one of the simulated ones, given that you can't tell the difference from the inside. Take your red pill now. Phil. How do you feel, Phil, about the... So, simulation. Have you come across this idea before,

that this whole thing is a piece of coded programming? I think it's more this area where science is intersecting with philosophy, I'm quite interested by. I like the idea that maybe, yeah, I'm not here. I quite like that. I like the idea that I'm not here, feeling very uncomfortable with scientists. In a room normally where I am an alpha, I normally...

LAUGHTER I normally make with the whimsy, and it's my territory, this room. And now I've been brought here at this stage of my life. I am 100 pounds overweight, and you're putting me to this sort of pressure. OK, I'll tell you what then we can change it so your subject is keanu reeves you have one minute phil jupiter happier now phil i am not um i wish he'd been in speed two

it's weird isn't it how a slow moving ocean liner wasn't as exciting as a bus going through a town. Isn't it weird how they... See, I kind of get worried about just the idea that if we are... If there are many of these simulations going on, what if this simulation is a kind of... It's being run as the equivalent of a public information film for all of the other sentient beings. And so the reason that we've got things, you know,

Donald Trump being president and various other political things, is that this is what is broadcast late at night to other sentient simulations to go, don't do this. Before you get mad, don't do this. We're a crap simulation. That's all you're putting out there.

It's a horrible feeling. It's that... It seems to sort of detract from your sense of being, that idea that we could be that. But to sort of detract from your from your sense of being that idea that that we could be that but the kind of the logic behind it is perfectly sound but you don't like the idea of it very much phil said that the logic is sound but if we try and unpick um some of the steps one of them of course is that it is possible to simulate consciousness in the way that we experience it in a computer. What's your feeling on that?

Well, that's definitely one of the other things that I think one has to assume to be possible to take the simulation argument seriously, that consciousness is something that can be instantiated when run on a sufficiently detailed computer of some sort, whether it's a computer like the ones we have today or something made of a quantum computer or a computer made of, I don't know, runner beans or something.

It doesn't matter what you run it on. And this is this idea of functionalism in philosophy of mind, that consciousness is what you call substrate independent. It doesn't matter what the hardware is. All that matters is the software. And this is quite attractive for a lot of people. They like to think this, partly because we use computers

to simulate very many things quite successfully, and because they've become the dominant metaphor for how we think about what brains do. We think of brains as doing information processing, so then it's kind of natural to think that if that's what brains do, and consciousness is another property that brains give rise to brains do and consciousness is another property that brains

give rise to then probably consciousness is something that you just get out of out of doing the right kind of information processing in this substrate independent way but i'm not comfortable with that assumption at all i think it's quite a dangerous assumption uh for a few reasons firstly that it's just not obvious that consciousness is the kind of thing that can be simulated. If we simulate a hurricane or a big storm inside a computer inside the Met Office, it does not get wet or windy inside the computer at all. Simulation doesn't have that kind of property. So why should a simulation of consciousness actually give rise to conscious experience? There's this distinction between simulation

and instantiation, which I think we need to pay attention to. Digest? Maybe consciousness is more like digestion. You can simulate digestion, but if you put food into a computer, it's not going to work very well, let alone enjoy its meal and go and... I can fully

back that up. Do not put a mini pizza into a disk drive. Don't eat a doughnut over a laptop. I did that. You can't get the sugar out. It is really hard. Your laptop has still got a floppy disk drive. I know. It's quite impressive.

Not I think it killed itself. But it also helps... There's a historical context here as well, because we always tend to take the dominant technology of the day and think that's how we explain the most important things about being human, about being us. So before computers, it was like, well, maybe the brain's some kind of complex network of plumbing, something like that.

And that would give you a set of metaphors for thinking about how bodies and brains work. Now we've got the computer, already people may be thinking about it's not the computer, it's the internet, something like that. It's very difficult to know in some future civilization that hasn't wiped

itself out, which to me seems actually probably by far the most likely outcome for any of the three possibilities, what the kind of technology that they will have will be to lead them to think what the best metaphor is for understanding their consciousness. But we do know something about the functioning of the human brain, which is that it is a physical structure that operates according to the laws of nature. So if we accept that, it seems difficult to understand why, in principle,

you can't simulate that system. I think you can, in principle, simulate it, but the question is not whether you can simulate it. The question is, does simulating it give rise to the property that you're simulating? So you can imagine, maybe if we take Nick's other steps and assume that we accept them, that there are these big simulations, running simulations of all our ancestors, simulations of lots of people, including simulations of their brains, inside worlds in a very kind of matrix way. Yeah, maybe we can accept all that without that leading to the conclusion that these simulated people are conscious.

But we know we are conscious. That's the one thing, back to Descartes and before, that we can be certain of, that we're having a conscious experience right here and right now. And it's still very much an open question whether that is the kind of thing that can be simulated. Would you agree with that, Nick? No, it's certainly true that there is a premise in the simulation argument,

which is you run exactly the same structure of computation that occurs in the human brain, and you would have the same experiences. Now, there might be a couple of things I can say to make that more plausible, although perhaps not to prove it in a short discussion. So one is to observe that it's a fairly commonly held view among computer scientists and neuroscientists and such, although by no means universally accepted. Another is this thought experiment where you imagine you start with your current biological human brain and you replace one neuron with some artificial chip that performs exactly the same input-output mapping as your original neuron. Presumably, you can't tell the difference. Certainly, you can't act any differently

than you did before, because it's functionally identical. Then you place a second neuron and a third neuron, and at the end of this process, your whole brain has been replaced by a small silicon equivalence, and at no point, it seems, would you notice any difference. The end result has to

then be an artificial mind that experiences the same as the original. I worry about that kind of argument, though, don't you? Because there's that old thing about when did bits of sand become a pile of sand? You can say you've got one grain of sand, that's not a pile of sand. You add another grain, it's still not a pile of sand.

And so you could say, if I just keep on adding grains of sand, in the same way that you would say let's replace one neuron with a non-neuron thing, like a little computer chip that has the same input-output, then you're saying there will be no qualitative change in what it does. But at some point, a collection of grains of sand does become a pile of sand. Right. So you kind of notice the pile of sand getting bigger.

But this argument would have it that you won't actually notice any difference in your subjective experience. Certainly you wouldn't be able to tell, because if your verbal expression changed, that means that there would be some different causal mechanism going on in the brain than before. So do you have to recreate all of a society's brains,

or do you just need one with the perspective of the history of a society's brains, or do you just need one with a perspective of the history of the society? Because all of us here are each experiencing this evening subjectively. So the initial question, are we living in a simulation, it doesn't matter, because we're just each experiencing it individually. So would this theoretical future society just have to create one individual experiencing?

So both are possible types. So you could... First, it might be that everybody is simulated in the same simulation and interacting. Now, it might be possible also to create smaller simulations where, in the limit, say, only one person is simulated but then you have the problem there are all these other people who appear in our experience world

so they would have to be simulated at least to the point where they appear indistinguishable from original people if you're going to have an ancestor simulation. So the question then is could you produce in a virtual reality a little avatar that behaves in all respects like a human being,

but without there actually being consciousness associated with that? So maybe, like, the cranium is empty, but they have some clever program that makes them sort of move their arms and their tongue and lungs. So they've got to pass the Turing test, basically. They would have to pass the Turing test. So I guess I'm agnostic whether it would be possible to have something that

behaved exactly like a human in all situations without it being conscious. It might be that if you put that much complexity in there, that that's enough for there automatically to be consciousness. But maybe you could, if there is a person who only appears like

somebody who sells you a train ticket behind a booth or something. There's a very limited interaction there. Maybe that you could fake without actually being. So I think you can entertain both possibilities. Ancestor simulations where a whole of human history may be going back, far back, is simulated. Or

sort of me simulations or a few people simulations where just smaller fractions or time segments of the entirety are simulated. These simulations, are they pictured as being, you said simulating the whole of human history. You couldn't do that, could you, in principle, because you don't have all the data necessary to recreate human history. There would be different variations of human-like histories.

And so then what you would have, if that took place, would be a world where there may be a million different trajectories, all of them but one, say, being simulated, and with different versions with human-like creatures having different empires rise and fall and different things happening. The question is, sitting inside one of these, would there be any sign that you could look at to tell whether you were in the one in a million real one

or whether you were in any of the other simulated ones? And so it's not obvious which sort of sign would be if there would be no systematic difference between these simulated worlds than the real one. Anno, in terms of looking at artificial intelligence research, how much thought is put into the ethics and the possible... Once these scenarios come out, once people have... I think Stephen Hawking actually talked a little bit

about a warning of artificial intelligence, of where that could go, and indeed, if we do get to the point of saying this could reach the point of simulation by intelligence that we have created that becomes far more intelligent than we are. How much is that thought of in the philosophy of AI? Probably not very much. The ethics are very important in AI and in neuroscience and many other developing fields as well, because I think science and the history of science has shown that people tend often to consider ethical questions a little bit after the fact, which is too late.

In this case, it still seems to me there are many... Given a kind of worried budget of the kinds of things we should be worrying about, there are lots of things going on with current technology that we should be concerned about. There are immediate problems with AI in society in terms of their economic impact and so on. And for me, it's sort of like, I find it interesting why people think this is, you know, what benefit do we get from considering this as a possibility, as a logical possibility?

And it seems like... I don't know whether you think... Is there something quite religious about it? It seems almost like a religion for atheists, where you've got a creation myth. We're all in a simulation. You've got a creator. You've potentially got an afterlife.

And you've got maybe a prophet. And you've got all the things you've potentially got an afterlife, and you've got maybe a prophet, and you've got all the things that go along with religious debates, like, well, if there was a god, how come there's also so much suffering? You could say, well, if there's a person creating, or a post-human or whatever it is, creating a simulation, why would they create it with all the problems of the current world? Do you... Nick, respond to that.

I think there are a lot of these analogues that you could draw between different kinds of theological scenarios and the simulation hypothesis. Sometimes in the theological context, you mean that the creator is literally infinite, literally omnipotent, etc., literally have no constraints. Whereas the simulators would be subject to the laws of physics,

they might be computationally limited, they might know a lot relative to us, because they have developed to post-human stage, maybe they have enhanced their own intelligence, but they wouldn't be literally infinite in their minds. They would be able to intervene in our worlds in a way that contradicted the laws of physics in our simulated world, but they would themselves be subject to physical constraints.

So there are some parallels and some dissimilarities. It's interesting to explore why, because I think that is a good question. It's like, why would we expend resources simulating reality? I can see why you can do it. We do it now in terms of the universe to see how galaxies form. And so we have quite coarse-grained simulations, but we have a reason for doing it, which is to find out how nature works, essentially check our theories of the evolution of the universe. So what is the motivation beyond that to start putting AIs into the simulation, as it were?

Well, I mean, we don't really know. There are certainly many conceivable motives. One would be scientific research, like run alternate histories to figure out what would have happened. So we could be this simulation where people said, let's see what happens if Trump won. That's what we could be living. Phil, what are you...

If we give you this power, and we might do, that you are able to, as we were saying, they're running different simulations, looking at different histories, and indeed you're involved. What are the first simulations you're going to be working on? Battle of Thermopylae. I'll nip there. Check that out. Quite like the idea. Battles.

Wars. Check those out. The thing is, is once you set it going, surely the interfering element is what I find perverse. I quite like the idea that you have a simulation with all the free will in it, just to see what might happen. But the fact that you have to lean in and flick a bloke to make him, you know, decide that he wants to run Germany, you know, that's... I'm going to make him a bad watercolourist and he's going to be very resentful. Whose brain's hurting just a little bit?

Who has reached that point of just going, right, this is real, it's not real, it's a sim... It's a really... That's the bit where... That's what I find so fascinating, is once you go into this world, once you start looking at it, you do end up in those positions where even Brian, who has normally been fluent, as you know, even replicant Brian Cox,

you have a slight malfunction there, because it just... I want to say that I find... I do find the argument persuasive. So I think what's interesting when we talk about this, and I think when you're listening to this discussion, it's very easy to dismiss it and say it sounds ridiculous that we could be living in a simulation. But I actually do find it difficult to refute any of the logical steps personally. And that's why I find it interesting.

Actually, that's what I find really... One of the things I find fascinating as well because thinking about consciousness in the brain a lot and I do think about whether functionalism is a sensible way to think about how the brain relates to consciousness and what the simulation argument does, I think, is it explores, well, let's take that as the case and what would follow from that logically

and I think what you've identified in the simulation argument is a possible set of circumstances that you have to take seriously if you accept that functionalism is is the case yeah and that's that to me is a very worthwhile and interesting point of view this is how because the one thing that i find particularly i find a bit like free will there's a slightly disconcerting element to this which is i think some people can react quite negatively like if you're told like free will, there's a slightly disconcerting element to this, which is I think some people can react quite negatively. Like if you're told that free will is an illusion and people take that on. I had someone once wrote to me and said,

is free will an illusion or not? And I said, why do you want to know? He said, I want to ask a girl out. And if free will is an illusion, then I won't bother. And I said, how are you going to make that decision? And he says, oh, yeah, that's difficult, isn't it? I don't know how that works. And then he went back to me and said,

well, I took your advice and I did ask her out, and she said no to me in front of all her mates. Thanks very much, science. But there is, when someone says... It's as if you can opt out. And I wonder if in the same way, to be told... You do get certain people who do take this on as a myth, almost as a religion, the idea of assimilation.

It can be, to some people, perhaps very disconcerting, a loss of a sense of self. But that's... I'm sitting here, and my perspective of it is always... is from my own standpoint, and it's... I remember as a kid thinking that, when someone explained my senses to me, I remember as a kid thinking that when someone explained my senses to me I remember as a kid thinking that it is just input that that I am reacting to and then when you get older and you

read about synapses and things like that and just then when Nick was saying about building a brain a synapse at a time. We are just physical structures. This is just such a massive thing to deal with, and I quite like what you said just then. Let's just take that there is a massive civilisation at some point in the future that has all technology available to them, and they are doing that.

If you follow that line of logic, you start to sit there thinking, I'm just a simulation, and that makes that line of logic, you start to sit there thinking, I'm just a simulation. And that makes me kind of morally bankrupt. I'm kind of looking forward to the weekend now, with a sense of abandon. I'd quit drinking for Glastonbury. I now deeply regret that. It is actually a very good point and a good question as to what it means, or what, for the individual, I suppose. If indeed we are living in a simulation,

does it matter? Yeah, I think it's the first approximation. I think the advice to living in a simulation would be to do the same things you would do if you were not in a simulation, in as much as the best guide to predicting what will happen next in the simulation, in as much as the best guide to predicting what will happen next in the simulation, if we're in one, would be to try to find patterns and extrapolate them

and build models of observances and so forth, the same scientific method that we would use otherwise. Now, that's the first approximation, but there might be some second-order differences if we're in a simulation, new possibilities enter. Like, for example, we think physics doesn't allow the universe just to sort of pop out of existence suddenly for no reason. If we're in a simulation, in principle,

if somebody turns the computer off, like, our world disappears. Things like an afterlife, which looks difficult to reconcile with the view that we're not in a simulation and living in basic physics as we understand it, because our brains rot and so forth, certainly become live candidates, at least, in a simulation. In principle, if the simulator is wanted,

after the simulation ends or after you die in the simulation, they could start the simulation over or lift you over to a different simulation or lift you out of the simulation into their level. All of these are now sort of possibilities that you could entertain. And there might be other more subtle differences as well, to the extent that you thought you had guesses about the reasons for creating these simulations.

So I understand your logic then. Given that it may well be very likely that we're living in a simulation, then you're saying it's also very likely there's an afterlife. No, I was saying that it is a possibility in a way that it doesn't, in a similarly obvious way, seem to be if we're living in basic physical reality. So there's this big tension, right, between the kind of current scientific world

where we are biological creatures that decay after our death and the information goes away and yet we think the information is what's us, and the idea of an afterlife, that you would have to have some... There's like a kind of a leap from that, right? Whereas in the simulation hypothesis, it seems like a very natural possibility.

If the simulators decided that that's what they wanted to do, there would be nothing preventing them. It sounded more attractive. I quite like the idea that... I mean, presumably because time, is time a constant? Oh God, I can't believe I'm on this show.

Brian, you can answer that one. You do that. Yeah, is time a constant? No, there's no universal time, absolute time. It's unique to each of us, depending on how we move relative to each other. So they could run their simulations. Could we be like on Fast Forward?

And we're getting to a point now where they're going, I didn't like that one, it finished up with Trump and Brexit, so let's start again. Control on delete. Let's start again, and this time, pink dinosaurs. I mean, it's just... See, we were talking about that this afternoon. I was interested in whether the simulation could be watched

at a different speed from what we're experiencing. So it doesn't necessarily mean that whatever simulator is now watching us, it has to watch for 13.7 billion years. It might mean that it can watch at a different speed. Right. You said it right. But I think it does matter. I think Nick's right, that if we are in a simulation,

then we just basically do the same thing we do anyway, do our science the same way, do our philosophy the same way, live our lives the same way. But it makes a difference in the same way that religion can make a difference to people's lives as well. It's the value you attach to all these things. And personally, for me, it would make a big difference that I find it quite valuable and quite illuminating and

quite reassuring to think that there is actually a real world out there and that we are discovering its properties and that I am, my consciousness, my experience is somehow very deeply grounded in my nature as a biological, as a living organism and is not just a matter of information processing.

Now, I agree that we don't know necessarily whether that's the fact of the matter, but it will make a difference to how you go about thinking about the value of your actions. So some of that would be true in the simulation hypothesis also, that there would be a real world out there. Also, we might be finding out things about it,

even if our world is simulated and we just look at the simulated world if that simulated world is similar in some ways to the underlying reality then we would be finding out indirectly things about the underlying basement reality by looking at the simulation which we do now

if the motive for creating the simulation if they wanted it to be as realistic as possible, then we would be finding out a lot about the underlying reality by looking at what kind of simulation was created. But there's already a sense in which the world that we experience we know is not a direct reflection of some external reality anyway. I mean, this goes back to these old ideas about skepticism and shadows on the cave and Plato and all that.

So when I see a colour out there, it's not because there is a colour out there, right? It's because it's useful for my brain's perceptual systems to create that property so it can guide my behaviour in this or that way. So, in a sense, our brains are running a kind of simulation of things happening out there in the world, and that's what underlies the way I perceive the world and the self. The way I experience my body is the brain's best guess of various things

that come into the brain from sight, from sense of where the body position is, and so on. But my experience of my body as an object in the world is a kind of controlled hallucination. It's not a direct reflection of the external reality. So in that sense, we are experiencing the product of a simulation, but it's a simulation that the brain is running for its own purposes. I was just thinking that if the whole kind of premise that you said at the beginning,

are we in a simulated universe? Well, if we are in this universe, the Rene Descartes in this simulation said, I think therefore I am. And he was just a simulation. I mean, he's given me quite the headache, this show. I've never seen a guest ever quite go, I don't know how this is changing me, but it is.

And it has been a rather wonderful journey to watch. Because that bit of... I love that idea of the... I think we talked about this once before, which is the possibility that the first time that you are able to live beyond your physical self would be to be programmed inside a computer game. And, you know, your relatives would go,

well, we've managed to get just enough of them, and we've placed them into this programme, and then you spend eternity as a Super Mario brother, because it's quite an early stage of technology. Oh, man, my mum would have loved it if I'd been a plumber. So, the final question is really, how do you change? I mean, I'll start with you, Nick. You've studied this for a long time.

Does this mean that you have, on this journey of finding out about ideas of simulation, does it change the way you look at your reality? Has the way you examine reality changed with this, or does it remain roughly the same? Yeah, I think, I mean, even more than before, I think it makes it plausible to me that there is more on heaven in heaven and on earth than than is dreamt of in in our philosophy i just think

we are relatively clueless about the really big picture questions and that it's conceivable that there is i call them them, crucial considerations, which is like some fact or argument such that if you discovered it, it would radically change your view about what you should do, your whole scheme of priorities. And it seems quite possible that we have overlooked at least one such consideration and that we are therefore effectively in the dark. Maybe we're making things better, but it's more or less accidentally, if we are.

And so some sense of epistemic humility in that sense. But I think there is also just a lot of things about implications and such that we don't yet understand very well. And so there might be more concrete, tangible ramifications flowing from it that are yet to be discovered. One of the things about studying consciousness is that it does make you experience the world differently. I think in the sense that my experiences of my experiences are different. I can have an experience of the world around me now and experience it sometimes without this naive realism.

That's the way it is. And that does change the way you go about your daily life. Now, the simulation argument or hypothesis, to me, doesn't do that in the same way. And maybe that's because I still think that this question of whether consciousness is simulatable is open. But even more, I think it would change my life if I was in search for some sort of creation myth,

but I'm not. The real world does me well enough. Phil? I, uh... LAUGHTER I think that it's... This whole show has made me... You're quite right. It has made me look very, very differently at, certainly, Great Portland Street when I leave this building.

I think, you know, the idea of, you know, people say, well, if you step out of the house, you could be knocked down by a bus tomorrow. At the moment, that would be sweet release. On that Morrissey note... We asked the audience a question as well some hours ago, and we asked them if you were going to simulate a world, what would you put in it and why?

And we have an infinite number of monkeys on typewriters in cages, so I could super fast-forward and see if any of them managed to write the works of Shakespeare. Brian's brain in David Tennant's body. Sorry, Robin. It says, well, sorry, Brian. So he knows that I'm the one who has to put the brain in the body because that's the stuff I do backstage.

Sir, John here says, I would put more pockets in jeans. We have so much stuff nowadays. Intelligent life. It's pretty boring with just Brian on a hilltop wittering on Ingrid, you could have written that Brian's D-ream haircut let's just say things can only get better

and then the Brian Cox hairdressing salon because he's worth it you know what I find annoying for all three of us why have we been simulated with hair loss anyway so Do you know what I find annoying? For all three of us, why have we been simulated with hair loss? Anyway, so... Not fair, is it, frankly? Thank you very much to our panel, who are Professor Nick Boster, Professor Anil Seth

and Professor Phil Jupitus. Next week, we are going to continue to disconcert you because we're going to ask, really, the question of whether you exist, the actual you-ness of you. Are you just a bundle of reactions and thoughts that imagine you are you? It's a tricky thing, self-consciousness. We are looking at the brain and the mind, and how much of the brain is your mind,

and what is the rest of it doing, Robin? So, we will find out, finally, the answer to the question, is it true that we only use 10% of the brain is your mind and what is the rest of it doing, Robin? So, we will find out finally the answer to the question, is it true that we only use 10% of the brain or does it just turn out the people who say we only use 10% of the brain only do? So, thank you very much. Bye-bye. Goodbye. APPLAUSE In the infinite monkey cage Without you traveling In the infinite monkey cage

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