The science of consciousness is solving the biggest illusion in our universe

You feel as though consciousness has and will one day have explanations which can be reduced to the physical

And so if we were to create an artificial intelligence which did have the desire or the will to survive

is that when things become dangerous? I think that no one should really be actively trying to create a conscious AI

It's like, why would you do that apart from the desire to play God? The difference between conscious systems and non-conscious systems

goes down to the level of the fact that we're made of cells

that regenerate their own components that transfer energy into matter and back again

We project consciousness into things that seem human-like in ways which might actually not matter at all

I feel that artificial consciousness, real artificial consciousness, if that's not an oxymoron, might require real artificial life

It's very tempting to think of the brain as a computer. People have been doing it for ages

And it's a powerful metaphor. It's a powerful map with which to explore some of the things that brains do

But we've always used a technological metaphor to understand the brain. And every time we have a metaphor, if we really think that is the thing

then we stop looking for what else might be there. And I think we need to start looking for what else might be there

that marks a difference between brains and even the most powerful computers

Hello, everybody, and hello, Anil. Hello, Jonny. So we're here to talk about consciousness today

and we're going to divide the talk into three acts, really. The first act, we're going to talk about the current state of consciousness science

and what we know at the moment about consciousness. The second act, we'll look at a more speculative view of what we can know about consciousness in the future

and, of course, AI. And then the third act, we'll open for questions from the audience, from you guys

So think of some good questions and at the end, we'll take some hands to ask for Anil

So I thought that if we're going to talk about it for an hour, we should probably define our terms first and ask you what consciousness is because presumably

everybody in this room has consciousness or is conscious right now we hope so um how do we define

it from a scientific point of view it is a good place to start but it's also a dangerous place to

start because i think we can we can get caught up in definition a bit too much i think it's important

to define it at least the extent we we're not talking about different things without realizing

it. I mean, consciousness on the one hand, I think it's still one of this great mysteries

You know, we have experiences of the world. How does it happen? But it's also the most familiar

We all know what consciousness is, as you said, Johnny. It's what goes away when you go into a

dreamless sleep or even more profoundly under general anesthesia. And it's what comes back on

the other side. It's hard to define without being a little bit circular. It's like any kind of

experience of the world, the redness of red, the paininess of pain. And I always like to use the

definition from the philosopher Thomas Nagel, who 51 years ago now put it like this. He said that

for a conscious organism, there is something it is like to be that organism, that it feels like

something to be a bat as he put it in his paper whereas it doesn't feel like anything to be a

table or a glass of water by almost any very few people would claim that and when you're when you're

out under general anesthesia it doesn't feel like anything to be you then either so i think that's a

good definition because it's very general doesn't really make any presuppositions about what what it

is like to be you just that there's something it is like to be a conscious thing so is it fair to

say that we can talk about a human species consciousness or would we have to look at every

individual human consciousness in this room oh in this room i was going to say every human would

take a long time in the world every every human in this i well it's it's it's likely that we

overestimate the similarity of conscious experiences even within the species. So Nagel

in his paper talked about a bat. I mean, he was making a larger point about whether consciousness

this fact that some things experience and other things don't, whether that was addressable by

science at all. But he kind of became more known for the idea that bats, assuming they are conscious

are going to have a very different kind of conscious experience. They have echolocation

So their experienced world, we humans can maybe approximate, but we can never really experience what it's like to be a bat without being a bat

And I think the same thing applies in a smaller way within a species too

It's easy to assume that other people experience things in the same way we do

because our conscious experience has the character that it, especially when it's experiences of the world rather than thoughts it seems as though it's

just there right just seems like you're there the wall is behind you that doesn't depend on my brain

you're just there but that's probably not what's going on everybody is creating their own unique

world now they won't be completely different i think human experience is likely to be

have a lot of commonalities but there are going to be interesting differences as well

great thank you yeah and so in your book being you you describe yourself as a physicalist which

is where and correct me if i'm wrong you feel as though consciousness has and will one day have

explanations which can be reduced to the physical so we can explain consciousness in physical terms

and i thought if we could explore a little bit about what's going on in the brain when we're

talking about consciousness but before we do that i was wondering if you could give us a quick primer

about the ways which we can currently measure what is going on in the brain

the fMRI and EEG and PCI talk about in the book. If you could quickly talk us through

Lots of things. They all tend to be compressed into acronyms for some reason. But firstly, though, yeah, you have all these isms

in the philosophy surrounding consciousness research. Now, we'll probably get back to that a bit later maybe

but I always think they should be worn a little bit lightly

So I sort of describe myself as a pragmatic physicalist. Like I don't believe in it as an ideology, as something that I know to be true and everything depends on it being true

I just think holding that attitude can deliver the most progress in understanding in practice, even if ultimately it turns out not to be the case if somehow we were able to discern that

So I think it's a pragmatic perspective rather than a fundamentally held belief about how

things are. Because of course you say reduced to the physical, I mean the physical is pretty

mysterious You know it not just like neurons or I mean the physical who knows what matter is really Matter is pretty mysterious and implacable when you get close to it So being a physicalist is not to sort of be too reductive and say oh yeah it just neurons

exchanging signals. It could be many, many other things. Brain imaging. So, I mean, for me, this is

like already a consequence of thinking, at least from the perspective of consciousness being a

property of a physical system. We just have a ton of evidence that conscious experiences

in human beings are intimately related to the human brain. And so it makes sense to start by

trying to track the footprints of consciousness in the brain, look at brain activity and see

how it varies as consciousness changes in human beings. And for me, it's been transformational

It's incredibly exciting that we can do this. You think about some of the other grand mysteries in science, like what happened at the beginning of time

What's the world really made of? You have challenges of looking far away and long ago or looking at the very small, and these require massive instrumentation

It's really hard. Human brains are pretty accessible. They're human-sized. There are lots of them to study

And that's a great advantage. And the fact that we have these brain imaging methods now, since about the 1990s, they've been widespread

Historically, that's what gave consciousness research, I think, its modern momentum. But there's still a problem because the challenge with imaging the human brain is not that it's far away or long ago or tiny, but that it's complex

So we have about 80, 86 billion neurons. Each of those is a very complex little biological machine wired up in very intricate ways

And we don't have a sort of James Webb telescope for complexity

We can look at the brain in reasonably high spatial detail, but then we lose time

We can look at it in high time detail, but then we lose space. And in neither case can we look at all 86 billion neurons at once

So we're always trading off things in different ways. so when most people encounter brain imaging they're usually seeing these fmri scans this is

functional magnetic resonance imaging it's wonderful technology you see these colored blobs

and pictures of the brain it's not actually measuring brain activity it's measuring something

about the the metabolic consequence of brain activity neurons fire they consume energy

blood blood oxygen levels change magnetic properties change that's what it's measuring

It's very indirect, and it's over a timescale of seconds, whereas neurons are on a timescale of milliseconds

That's one technique. In my lab, we use a lot of EEG, electroencephalography

It's probably the oldest. Neurons generate little electromagnetic fields when they do stuff

and we can measure the collective impact of those electromagnetic changes. And that's very fast

We do have sensors over the brain. You don't need so much fancy kit, but it's fairly low resolution

It's a bit like dangling a microphone above the center of Oxford and trying to figure out what individual people are saying to each other

You can't discern the fine-grained chatter between individual people, and maybe that's where the detail is

And so then you have the method of sticking wires directly into people's brains, which I do not do in my lab

You have to have good clinical reasons to do that. then you know exactly where the neurons are and you know exactly what they're doing

but you can only typically measure a few of them at a time. This is growing. People can measure

maybe hundreds, perhaps thousands now, but that's a tiny, tiny fraction of the billions that you have

So those are the sorts of techniques that we have to use. So if we have these trade-offs all of the

time when we're measuring consciousness and even then you say yourself that it's slightly

inadequate at the moment, do you think the problem of measuring consciousness is one of technology

that we haven't got the right scanning equipment available to us? Or is it one of science that we will require a completely different scientific paradigm to accommodate consciousness

You're giving me two options, neither of which are very appealing. I mean, it's like, I think it's that, I think it's both of those and more, but slightly different

So the problem of measuring the brain is kind of a technological problem

that's going to depend on scientific innovations, like developing new ways to measure signals, really what's happening in the physiology

There are some new ideas, but we're reasonably stuck with what we have

One new idea, for instance, which you can't do in humans, which is really changing things, is called optogenetics

So this is where you actually modify the genomes of animals and you so such that neurons actually express they give out light or they reflect light in

different ways so you can find out a lot that way but you can't do this in human beings because

you've got to genetically modify them anyway that's one problem that's the scientific technological problem that's not measuring consciousness that's measuring the brain

so then you have to ask how do you connect changes in consciousness to the changes that

you see in in the brain and you can do this like in a very exploratory way you know just

put somebody out under anesthesia, see what happens, or watch what happens when they go to sleep

or many other experimental paradigms. But you'll see a lot of things change in the brain. How do

you know which of those things are specifically to do with consciousness? So then you have to have

theories that try and bridge the two. And I think that's kind of where we are now. We have a bunch

of theories that make different predictions about what happens in the brain as consciousness changes

but you're right that it's very hard to tell them apart and part of the problem is that we

we lack the precision in our measurements but also the precision in our theories they don't make

that precise predictions just at the moment so hypothetically do you think there could be a

technology which can measure thomas nagle's degree of first personhood qualia or are you

saying that we will always deal in correlations, that we'll always have to say this is the physical

thing happening and therefore we have to correlate it to some kind of consciousness as a kind of

inference or do you think we will have a technology which can identify first personhood

I think we start with correlations. When we're trying to understand a phenomenon empirically

that is resistive to our understanding, a good way to start is just by seeing

looking for correlations, what goes with what. But that's just the starting point

And you want to go from correlation towards explanation so that you have a sense of why X goes with Y

I mean, you see there's like all these crazy examples of the price of cheese in Wisconsin has correlated over time with a divorce rate in France

That means nothing, I think. I don't know. Maybe it does. But it probably means nothing

It's just a correlation. There's no explanatory insight gained. And if you say, oh, look, we see activity in whatever area change when you fall asleep and just leave it at that, that also doesn't really give you much explanatory insight

So you need to get to the stage of like ah this process happening in the brain that tells me something about the conscious experience that going on or the fact that there is one versus

there not being one and that's partly a technological challenge i think the the more we can

do with improving these methods the the better but it's i don't think that's the it would be

helpful but there's an awful lot we can do without that part of the challenge is more of a

a mathematical one. We like the tools to deal with the complexity of the data that we have

even with the relatively low resolution imaging methods that already exist. And as we get more

towards explanation, I think we are making progress in that way. Then will we get as far as

answering this hard problem? I think that was mentioned, why is consciousness there at all

what's it got to do with the physical world maybe we will maybe we won't but we'll certainly get

further towards that that is a sort of an end point as a goal great thank you so if we're talking

about correlations and neural consciousness correlation you talk about nccs in the book

acronyms with the current state of consciousness science neuroscience at the moment if we were to

give everybody in this room here an eeg or some kind of brain scanner with what degree of certainty

could you infer what is going on in people's minds? Because I know in the book you talk about consciousness level

consciousness content, and consciousness selfhood. With what degree of certainty could you predict what's going on

in seat J4 right now? Who's sitting in J4? I don't know

So, yeah, I think you're right. Well, I like to think of these three different aspects of consciousness

Level, how conscious you are. Content, what you're conscious of. and self the the experience of being who you are the experience of being the subject of experience

which is which is really a subset of content it's a subset of your overall conscious experience but

i think it's worth its own category because it's it's rather special if everyone was wearing eeg

and the data was good it's kind of not too difficult to predict whether you're conscious

or not that that that can be done human beings in conscious states have you know their very their

brain activity is relatively predictable in some ways you have lots of sort of fast oscillations

going on um in various frequency bands and there are other more sophisticated ways of measuring

this and when you fall asleep you see you see very distinct patterns when you fall asleep and

you're not dreaming. Same under anesthesia. So that, I think that would be, that would be fine

for most people. But even then it's, it's like there are weird, there are weird edge cases

You know, there are people who, who have brain injuries for instance, and then it might be harder

You know, if someone has, is in something called the vegetative state or the wakeful unawareness

state, they might look awake, but they also look like there's nobody at home. And then it becomes

a much more tricky problem to predict, tell whether there's any consciousness going on inside

When it comes to predicting what you're conscious of, it's much, much harder. But there is this

growing research field of brain reading now. I mean, people used to call it mind reading

but now there's brain reading. And brain reading is precisely this. Brain reading is taking somebody's brain signals, measuring them somehow, and then trying to predict

what they are thinking, what they are experiencing. This is one of those things that's moving from science fiction into science reality

And there are some already really, to me, impressive examples of this

that are usually used in clinical cases. So people, for instance, who are paralyzed

you can now begin to read out their movement intentions so you can help them control robots

or maybe even guide their own arms by stimulating muscles, decode what they want to say

so they can regain the ability to communicate in some cases. So there's a strong impetus for this to be done

But there's also the issue of this is actually a very dangerous technology in many ways

We think we have freedom of speech, which is arguable in some cases, but very few places have freedom of thought

And once you have brain imaging things that are predicting what you're thinking

then you've lost that last bastion of privacy, because once you get inside the skull, there's nowhere else left

And also these algorithms that do these predictions are not perfect. So your brain reading might be inaccurate

And also you might be forced to think in a particular way for the thing to work

But technology is moving in this direction. This whole field of brain-computer interfaces is really all about this

And actually, it's very exciting, but it's to me also ethically really rather worrying

But right as we stand now, I don't think we'd be able to predict with great certainty what you were all thinking right here and right now

But I think that might change. I'm advising a couple of companies that are trying to do brain reading with consumer EEG

and they're getting quite far. It's quite astonishing. So you're right. In your book, you talk about lots of isms around consciousness

and about philosophy generally, really, to be honest. But you identify as a physicalist

Pragmatic physicalist. Pragmatic physicalist, but agnostic about functionism. Is that right? Yeah, I quite like it

Yeah, quite like it. So you're leaning more towards functionism. I think you've got to be flexible

Like, yeah, I'd be disappointed if I held exactly the same view. Can we probably explain functionism first

Yeah. So, well, it's kind of a sub. So, physicalism is the position that consciousness is a property of the physical world, of material stuff generally

It's kind of one of the bedrock assumptions of science as it's been done for the last hundred years

that things are properties of physical stuff, whether it's electrons or some higher level of description

That's physicalism. It's really, you know, originally might have been opposed to something like dualism

which is that, yes, you've got physical stuff, neurons and whatever neurons are made of

but then the world of the mind, the world of the mental is completely different

René Descartes was sort of famous for articulating this position. And then right on the other side, you've got idealism

which is the view that actually the physical world doesn't really exist

The only thing that really exists is mental stuff, mind stuff, and what seems to be physical is just a manifestation of the mental

Within physicalism then, within this idea that consciousness is somehow a property of the physical world

one of the most popular flavors of that is functionalism. And that's saying that consciousness is a property of the physical world, it's a property

of the brain perhaps in its body in the bodies in the world And what matters for consciousness to be a property of the brain is the functional organization of the brain um not intrinsically what it is but but what it does in in some sense how it organized and this can be

on the inside too how it's wired up what its causal architecture is that's all part of

functionalism and that's probably the the prevailing idea among most people working in

in consciousness science and from a neuroscience perspective. So it's pretty liberal

I mean, it's not like it's not it's it's it needs to be distinguished

from much more specific claims, which we'll get onto, like the brain is a computer and consciousness is this algorithm

I mean, that's that's a very specific kind of. Of function, right

We'll come back to that, I guess, when we talk about AI a bit later on. But before that, I want to talk about ism

And that's ism, which is very popular in philosophy at the moment. and some people in this room even are panpsychists and panpsychism

So I wonder if you could just quickly tell us what panpsychism is and why you are possibly less excited about it than some people

Well, how many people are panpsychists? Let's see. Well, half a hand, half a hand

I know there's going to be. Not many, not many. Well, maybe we could explain. Maybe more people will be coming after I've tried to pour cold water on it

The question is, how many people are panpsychists? All right, so we'll start with that

We'll start with that. So we've had the idea that consciousness is part of the physical world

or it's a property of physical stuff, or that everything that exists is mind

Then panpsychism is the idea that, okay, there is a physical world

but consciousness is also fundamental. it's a fundamental property of the world that we inhabit a fundamental property of the universe

a little of the same status as something like mass or electrical charge you know that's it that's

where things bottom out like most things you can say the table is something is the way it is because

it's made of wood and it has legs and you can keep going down eventually you get to electrons or

quarks or whatever you want to do. Somewhere you bottom out. Panpsychism is the idea that

you bottom out at consciousness as well, that it's there from the beginning. There's no point

asking how it's generated by something else or arises or emerges from something else

It's just there from the very beginning. So now that I've explained what panpsychism is

I think that's, hopefully that's reasonably not inaccurate. How many people feel like attracted by that idea

Okay, a few more now. Right. It's still a minority. You're right, though

It's becoming, it's having its kind of day in the sun, I think

And yeah, I also, I'm not remotely persuaded by it. And there are a few reasons for it

Firstly, it might be right. all of these all of these positions we've been talking about they none of them can actually be

tested they're all kind of can't decide whether it's actually a property of physics or it's a

or the world is all mental they're all ways of thinking about things um but panpsychism strikes

me as not a very useful or productive way to think about things even if it ultimately might

be right. And I think there's a few, there's like some very quick reasons for this. One is

that it's mainly seems motivated by a suspicion that a physicalist explanation isn't enough

that people think, well, you'll never be able to explain consciousness in terms of neurons or brains or carbons or computation or whatever it might be. You'll never be able to do

that. You'll always be missing the point somewhere. You'll always be explaining some other thing that's

not really consciousness and so if you're always missing the point and you're always going to miss

the point then it has to be something else and one of the other ways think about it is well if

it's just there from the beginning then then great you don't have to explain how it's produced by or

is identical to something else but I think that really underestimates how far we can get with

with materialism just because something might seem a bit mysterious now doesn't mean it will always

therefore seem mysterious at all um so that's i just i'm suspicious of the motivation and then

i don't think it gets even if you did buy into it i don't think it gets you anywhere so pantheikism

is often caricatured a little bit as saying that things like tables or spoons are conscious like

everything is conscious it's not saying that it's saying that it's fundamental like an electron might

have a little bit of consciousness but it's going to be nothing like the consciousness of you or me

or a bat or a bee if there's nothing really that you can grab onto there then it doesn't help you

explain anything the fact that the consciousness of an electron is nothing like the consciousness

of me well therefore what's what explanatory like how does it tell me anything about what it's like

to drink a glass of water or or fall asleep or dream doesn't it just doesn't um and then the

worst thing oh no the second worst thing is that not only is it not testable but it doesn't lead

to testable predictions if you think in this sort of panpsychic way another way it's often motivated

is that science tends to tell us what things do but not what they are um and maybe we're interested

in what things are and of course we are but what things are is is kind of what they do at an at

another at another level some panpsychist arguments say that consciousness is the intrinsic

nature of everything it's it's what things are that's completely separable from what they do

at the most fundamental level so even if you have other forces in physics like gravity or the strong

nuclear force they're still about what things do but consciousness may be actually what things are

But if that's the case, then you're basically admitting that it can never make a difference to anything

If it's fundamentally about what things are, if it's nothing to do with what things do or their disposition to do things, it can never make a difference to anything

So that's fairly useless. So are you against emergence as a property? Absolutely

So the idea that emergence is the idea, correct me if I'm wrong, that consciousness is something which emerges from these physical neural correlates we talked about earlier, but it itself is not reducible to the parts that make it up

I like the way of thinking that emergence is all about. And again, it's a tricky, it's a very slippery concept that's often used quite lazily

You have something, it's often used as a substitute for an actual explanation

Like you have a load of neurons in our brain and you say, oh yeah, consciousness emerges from the collective activity of our billions of neurons

Of course, if you just say that, you're not really saying anything at all

Having said that, I think it's the starting point from which you can develop useful explanations

Emergence is a sensible way of thinking about systems. I think often about in Brighton where I live..

And in the winter, in the evenings around sunset, these murmurations of starlings start flocking and then they settle to roost on the ruins of the Old West here

It's beautiful. And when they start to flock, the flock seems to have a kind of autonomy, a mind of its own, an existence of its own

It seems to be more than the sum of its parts. Yet, of course, we know there's just birds flying around

You know, there's nothing spooky or mysterious going on there. They're just birds flying around

But sometimes when they do this, they flock and sometimes they don't

And we can figure out how we might measure that. And that's part of the work we do in my lab

We try and develop mathematical ways of measuring the flockiness of starlings

And the thing is, if you can do that with starlings, then you can generalize and you can say, OK, maybe neurons flock, but not in three dimensional space

but in some bigger high-dimensional space of however many neurons. Does that explain consciousness

No, I don't think it does. But it can give us something that's a little bit more than a brute correlation

Because when we do have a conscious experience, one of the things about it is it's unified

We have a single experience at a time, and it's composed of many different parts

and in our brain we have many different parts that whose activity seems to be more coordinated

in particular ways when we're conscious so maybe the mathematics of emergence give us a handle on

how the brain is related to consciousness which is a very different perspective from just saying

oh you have neurons and then consciousness sort of emerges from their activity you know like i

I don't know, whatever, Aladdin rubbing his lamp and what comes out

I've forgotten now. Genie. Genie comes out of the lamp. Yeah. So that's the wrong way to think about it

I think there are some much more productive ways to think about it, which are also perfectly compatible with the idea that reductionism holds

Like the birds again, the flock of birds. Nothing new physically comes into the world, right

But the flock is kind of real. the flock being there changes how the birds behave this table too is it is in some sense

emergent from the things that make it up but the table is also real but nothing spooky or magical

is happening just because there's a table there rather than a whole bunch of of electrons

we talked about ai okay and um we mentioned earlier how you're a functionalist and how

you feel as though consciousness can be explained by the function of the physical composition

Well, I think that's like a gambit, right? I think that's the strategy. I don't know if it's true

Somewhat better than agnostic now, you think, maybe. And so we're talking about AI. So when

you're writing You're Being You, I was reading it a couple of days ago, you were actually writing at the time of ChatGPT3. So this was four years ago. I actually didn't realize how recent

how far away that was. Before we talk about AI, could you give us a quick primer about

how existing large language models are made and artificial intelligence are made

because we often talk about neural networks and neural symbiotic or symbolic networks

and how they are different, if they are different, to the human neural networks

Yeah, I mean, I think there's too much to say about that, which we won't, but I think perhaps the thing to draw out of that

is that firstly, these things are amazing. You're right. When I remember, I look back at that chapter now

I wrote about my last chapter in the book was about AI, and it was written just when language models were breaking through

into the public sphere, and they have been transformational. And to me, it's amazing how quickly we get used to them

It's like, ah, they exist now, we're used to them. How we adapt so quickly, it's really, really strange

And there are many technical details of how they do what they do, but I think the thing to dwell on here is..

In all the AI systems that are populating the world today, whether they're language models or AlphaFold

which predicts protein structures and things like that, they're based at least in part, if not almost in whole

on artificial neural networks. And these are an abstraction. They're an abstraction of brains in general

and basically they're little units that are wired together. I mean, in an actual computer

they're just simulations of these little units. They aren't actually little units

They're wired together. They exchange signals. They look a little bit like a brain

Neurons are wired up together and so on. And signals flow and you can apply different training algorithms

and enormous amounts of data and wonderful things happen like language models

The problem is, or at least the problem when it comes to thinking about whether AI built this way will ever have all the properties that human brains have, is that human brains are much more than that

So these artificial neural networks are a pale abstraction of the real biological complexity of what's inside each of our skulls

Does that matter? Does it matter that there's more going on? It might not, but it really might matter that there is more going on

And I think actually when we see some of the limits of what AI can do

they're not necessarily things that are going to be solved just by increasing the amount of computer power or the amount of data

it might be because we've actually accidentally um reified a metaphor we've confused the map with a territory it's very

tempting to think of the brain as a computer people have been doing it for ages and it's a powerful metaphor it's a powerful

map with which to explore some of the things that brains do

but we've always used a technological metaphor to understand the brain and it's always been limited and i don't think there's a reason why this is

different. It's just a metaphor that's now reaching the end of its utility. And every time we have a

metaphor, if we really think that is the thing, then we stop looking for what else might be there

And I think we need to start looking for what else might be there that marks a difference between

brains and even the most powerful computers. You mentioned Nagel at the start, and of course

Nagel talks about bats and in your book as well, you're quite happy to say that certain animals

potentially could have consciousness, a degree of consciousness, even if it's not the same

as you mentioned earlier, as human consciousness. So why can we not ascribe that also to artificial

intelligence or does artificial intelligence lack a necessary component that all of the animals

that you're quite happy to say are conscious do have? And what is that necessary component

Yeah, this is like literally the billion dollar question in some ways, isn't it

given the amount of money that flowing around in AI these days I had my PhD in AI but it seems to be about 20 years too early for it to be monetarily useful So the contrast between non animals like I don know a hamster or a fish and an AI system I think is really really instructive

I think we can be a lot more confident about consciousness being a property of many non-human animals

There are good questions to ask about whether all non-human animals have some kind of consciousness or whether it does kind of gray out into nothingness somewhere

For me, I start to feel uncomfortable around insects. I don't really know what to say about insects

But we're all made of the same stuff. Does that matter? We'll get to that

We're all made of the same stuff. And we all, in some sense, have similar problems to solve

to keep a body alive, to navigate an environment and to integrate lots of different kinds of information together

We can never be certain about anything. I don't even know whether you are actually conscious

though my prior is fairly high that you are. But we always have to infer

Some philosophers will tell you that you don't even know if you're conscious, which is, who knows

and the further we get from the benchmark human case then the more unsafe our inferences are

and that's part of the the work that needs to be done now is we have to like

generalize very slowly and carefully into the into the zone of uncertainty and try and

push that further and and further out as we understand more about what is really underpinning

consciousness in us and what's not just contingent on the fact that we're humans like for instance

if you think consciousness is associated with something really distinctively human, like sophisticated language

Other species have language too, but the ability to write poems or something like that

Then you're not going to attribute it to many other species at all

But that's a view that's rooted in our unfortunate human tendency to put humans at the center of everything

rather than being an insight into what's actually going on in the world

And I think that's also what misleads us when it comes to AI. We project consciousness into things that seem human-like in ways which might actually not matter at all

Now, up until a few years ago, if anything spoke to you with a fluency of chat GPT

you'd be very justified in saying that was conscious. If someone with brain injury suddenly started conversing with you in depth

you can be pretty sure they'd regained consciousness. but now we have an example of a system where that inference might not be safe because there are just

other ways of doing it it turns out not perfect they're not for anyone who's chatted for long

enough they're not perfect but they're pretty pretty good i think we project these these these

psychological biases that we all have where we see the world through the lens of being human and so

we overestimate the plausibility of machine consciousness nobody i thinks that alpha fold

which is this AI system that folds proteins is conscious because it doesn't speak to us but it's

basically doing the same kind of thing under the hood and that's telling I think it tells us that

our tendency to attribute consciousness to AI is largely a property of what we think rather than

what's there then there are deeper questions about whether consciousness could ever be a property of

of computation and here I think there's a lot of people disagree with each other and with me about

this but I think that brains do a lot more than algorithms and that I think the things that they

do that are not algorithms actually do matter for consciousness so I don't I think AI systems

might persuasively appear to be conscious and that's problematic in its own ways but I think

the chances of AI actually being conscious with the current systems that we have, even if you just

like let them run and see where we are, like chat GPT-10 or something like that, I don't think we'll

get any closer at all. We might get stuff that's much more persuasive than it is, but I don't think

we'll get stuff that actually moves the needle on being conscious. So what would it take for you to

ascribe consciousness to an AI? Or do you think even the word artificial consciousness is impossible

Do you think it has to be embodied? Do you think it has to be organic and natural? I mean, I don't know for sure

I'm always wary of overconfidence in both directions here. I think that's part of the problem

I think people who are very, very confident that conscious AI is coming or it's already here

I think they're unjustified in that level of confidence. I also think people who say it's for sure impossible are also overconfident in completely ruling it out

My bias is that it's very unlikely. And the reason I think it's unlikely is because the kind of explanation of consciousness that's starting to make sense to me is that it's a property of living systems

It's closely tied to the fact that we are creatures with metabolism, with physiology, with all this other stuff that's not computational going on

that actually gives us insight into why consciousness is the way it is, why it happens at all

And one thing that sort of leaps out when you look at the brain for what it is and not look at it through the lenses of an algorithm

is that in the brain there's no sharp distinction between the mindware, like what we think, what our brain, what our mind does

and the wetware, the physiology of our brain. There's no sharp dividing line

it's kind of vertically integrated all the way from brain regions down to an individual

cell. In a computer there's a sharp division between software and hardware which is by design

what makes computers useful. Real brains aren't like that and so there's a kind of through line

at least for me about how we understand what the brain is doing at a larger scale that might

determine whether I'm conscious or where my visual experience is going and what it's doing

at a much smaller scale of the business of actually staying alive, using metabolism to

regenerate itself. There's a through line, at least I think there's a through line

So I feel that artificial consciousness, real artificial consciousness, if that's not an

oxymoron, might require real artificial life. So you mentioned in your book about beast machine

theory, which is kind of what you're saying there, really, that a consciousness needs to

basically look after itself, want itself to live and to survive. And so if we were to create an

artificial intelligence, which did have the desire or the will to survive, is that when things become

dangerous? You mentioned in the book, for example, I can't remember the name of the philosopher who, is it Metzinger who asked for a 30-year freeze on consciousness research because programming

an artificial intelligence with the desire to keep itself alive, which is what you're saying

there which might be necessary for consciousness suddenly becomes quite a dangerous prospect Well not really any of those um so metzinger firstly fortunately he didn call for a freeze on consciousness research he called for a moratorium on on research into

developing machine consciousness now i i honestly i kind of agree with him though i i think that

no one should be really be actively trying to create a conscious ai it's like why would you

do that apart from the desire to play god it's a bit of a strange goal to have it's ethically very

very dubious indeed fortunately i think it's very unlikely to um to happen there are many other

theories that that do suggest that consciousness is just a matter of computation and if they are

right and they may be right then it's much more likely than i think it is which would i think be

a bad thing but if i'm on the right track who knows that that life something to do with life

is important that is not the same as just programming a robot with a with a with a sort

of motivation to charge its batteries every every now and again because described that way you're

still kind of importing all the assumptions and the and the legacy of this computational view that

it's programmed to do so we're not programmed to do that you know we're not programmed to have

metabolism we have metabolism we often talk too loosely about this with our genes as well to our

genes are programmed or they program us to do this or that. No, they're just part of the deeply

complex integrated physiological system that we are. So I don't think it would be enough to

have, let's say, a fancy humanoid robot that you then program its digital brain to go and make sure

it plugs itself in or repairs itself if it gets damaged. My suspicion is that the difference

between conscious systems and non-conscious systems goes deeper it goes down to the level

of the fact that we're made of of cells that regenerate their own components um that transfer

energy into matter and and back again i think that's critical of course i have to say i don't

know that that's the case but i think it it gives a good explanatory grip on why consciousness is

is the way it is. I think more worrying for me than AI in this sense is people are now building

these so-called brain organoids. These are collections of brain cells in dishes in the lab

that again for very good reasons for medical research and so on and they don't do anything

particularly interesting so people aren't yet very worried about the fact they might be conscious

at least not in the in the public domain but they're made out of the same stuff. So a whole

kind of area of uncertainty goes away i mean who knows whether i'm on the right track that being

alive matters in some way but once you start creating living systems then i might be right

i might be wrong it doesn't matter because that that's already being done you've already put that

condition in and as these systems get more more complex then they may start to have the capacity

to experience in a way that we may never even be tempted to notice because they're not going to

do anything. One more question before we pass to the audience for questions. And as you were

talking now, I was thinking about, it might be slightly outside of your area of research, but

there's a lot of research at the moment about how conscious might be distributed across different

parts of our body, particularly our gut microbe. And I was wondering whether we can look for clues

outside of the brain if we're talking about it as a kind of embodied experience

Yeah, this is such an interesting question. I mean, I think another unfortunate habit of a neuroscientist

perhaps unsurprisingly given the name, is the sort of focus on the brain to the neglect of the rest of the body

I think this has been a problem because brains didn't evolve without the context of the body

and the body is in continual dialogue with the brain. And indeed, neurons aren't just in the brain

We have a bunch of neurons in our gut. We've got some around our heart. There's probably neurons elsewhere

The neurons in our gut generate the most serotonin, this chemical that's often influencing brain function

A lot of that's coming from the gut. The neurons in the gut also generate brain rhythms

They oscillate together and they can be synchronized with rhythms in the main brain

brain so i have no doubt well i think it's very very likely and there's good evidence i should

never say i have no doubt always got some amount of doubt um i think there's there's very good

evidence and reason and reason to believe that what brains do is very very intimately related

to what's going on in the body and that involves neurons outside of the brain as well it's a very

different question to say is your gut conscious i think your gut can affect consciousness is it

self-conscious? I don't know. I think it's unlikely. The reason I think it's unlikely is that

there's no good reason for it to have to be conscious. Consciousness for us seems to be

associated with guiding behavior and integrating lots of different information in ways which the

gut by itself doesn't have to do. And even large parts of your brain, my brain, aren't particularly

involved in consciousness. It's not something that is generally useful for everything that's

biological so i don't think you got his conscious great questions from the audience really i think

there is a roaming mic um if anyone upstairs wants to speak i'll just say it louder for you

because there's no mic up there so if you guys want to speak please do yes um you said you said

earlier and i agree with this that there's no um sharp boundary between the mind's hardware and the

the brain's hardware and the mind's software. And so, as you say, you need a whole body with a brain in it

Do you think that if computers were big enough to be able to simulate all of that

do you think that it might then be possible to have artificial intelligence

Thank you. That's a wonderful question. What if we had enough computational oomph to simulate all the intricate detail

right down to whatever level this is a beautiful question people talk about this in terms of whole

brain emulation and people actually i think have or some people have the hope that if they do this

and they emulate their own whole brain they can somehow upload themselves into it and live forever

in some sort of weird silicon rapture the first question is whether there would be anything it

would be like to be a whole brain emulation is another way of phrasing your question right

I don't think so. And I think the key reason why is you hint at a very important distinction

which is that simulation of something is, in general, not the same as a recreation of that

thing. I mean, this is just, I mean, one of the reasons computers are so useful is they can simulate

basically anything. That's one of their wonderful properties. In most cases, we're completely

unconfused about the fact that the simulation is not recreating the thing being simulated

If we simulate a weather system we do not expect it to actually get windy or start raining inside the computer right And it just not nobody I mean some people say well maybe for a simulated person within it it would be wet But that building in the assumption that a simulation of brain is enough

But you always drop detail when you do that. Well, I mean, but let's, you know, the luxury of a thought experiment

let's just assume that you don't, and you don't drop any detail. That's why you need a computer the size of the universe or something like that

But even if you do that, even if you had a computer the size of the universe simulating a rainstorm, it's still not wet

It's just a very, very, very, very detailed simulation. The only times where simulation of something actually generates the thing is if the thing is itself a computation

Like if I simulate an algorithm, like something that maps some numbers to another number

then then i'm recreating that algorithm because it is its nature is is computation

so basically it's it's a gamble like whole brain emulation would be enough if

computation is sufficient for consciousness then you're okay but the weird thing is like

if computation is sufficient for consciousness then the whole motivation to do this kind of

whole brain emulation is really undermined because the point of doing it is this sort of idea that

well, the detail matters. And if the detail matters, then it's very unlikely that computation

will be enough because computation is motivated by the idea that the detail doesn't matter

I've always had a problem that there's something that it's like to be me

because a lot of the most significant conscious activity that I engage in

almost necessarily involves a loss of a sense of self. If you think of sport, like I used to do a lot of sport

at the moment you're in an important match doing stuff. You're engaged in conscious, intelligent activity

But there isn't really anything that it's like to be. You're just doing it. When you're writing, you can either have a kind of pre-reflective rehearsal of what you're going to write, or just write or speak

You know, you externalise thought, but you haven't had a pre-rehearsal necessarily internally that's the thought that you then express

Like I'm now, sorry, I'm slightly choked up on my voice. I'm now trying to speak, and I'm conscious of my voice, but I'm not conscious of what I'm going to say next

It just comes from nowhere. And it's conscious activity. And at the best, the best questions I've ever asked as an interviewer or somebody in the audience..

Like this one. Well, it may be a terrible one, but it's just coming out. It's not like it's something that it's like to be me all the time

I only get there's something that it's like to be me when I stop and then reflect. And that's a kind of confabulation at that point

So I don't think I explained myself or Thomas Nagel properly then. it's not about self-reflective awareness the idea of consciousness being it being there is something

it is like to be you doesn't mean that you are thinking oh it's like this to be me i am playing

sport or i am thinking about what to say when you are playing sport or thinking about or talking or

whatever you're doing there is some experience going on you do not have to i think that's part

of the force of this definition that it doesn't assume an ego it doesn't assume a self it just

assumes that there is some kind of conscious experience happening a lot of discussion these

days about minimal phenomenal experience for a human being what is the simplest experience it's

possible for a human being to have and one of the interesting angles on this is is um

states where there's complete dissolution of the ego this might be in very very deep states of

meditation it might be in um after some kinds of psychedelics um it might be in some other

situations as well but there seem to be some states where the ego is is not just like partially

as it might be when you're playing sport or playing an instrument, let's say

But wholly gone, there is no experience of self whatsoever. The point is that consciousness is still happening

You have no reflexivity on it, but it's still happening. Many non-human animals may have this kind of thing

They may have conscious experiences, but without a sense of self there

The whole point is that all that you're asking in this definition is that experiencing is going on

Not that there has to be the experience of being the subject of experience

That's something extra. Can I just come back very, very quickly? Doesn't that imply there's an experiencer

How can you have an experience without an experiencer? There has to be some locus to the experience

But you're confusing two different things here. You're confusing the fact there has to be something where the experience is happening

There's experiencing going on, but there doesn't have to be a conscious experience for a conscious experience

There just has to be conscious experience. I could lose my sense of ego completely and still be conscious

If these brain organoids get to a sufficient level of complexity, they may have a conscious experience without being at all aware that they are having it

because there is no ego in an organoid. It's odd because we humans, we walk around with our egos all the time

A newborn baby might be a little bit like this. And also ego comes in. It doesn't have to be the full reflective like, I'm thinking this

The fact that we have a first person perspective and distinguish ourselves from the other

That's all part of the ego. All of this can go away. And consciousness is still possible, certainly conceptually

It doesn't make sense to talk about consciousness without the ego. Yeah. Because in your book, for example, you distinguish between intelligence and consciousness, and you say the two are different

So does it make sense to talk about consciousness without the ego, or will that not just be intelligence

No, you can't subtract an apple from a pear and get a meringue. No

I think they're very different things. So the confusion of intelligence and consciousness is, again, one reason I think people falsely think that AI is about to become conscious

because we think we're intelligent and we know we're conscious so we put them together. AI is I

think pretty good example of how you can get some forms of intelligence without having to

attribute consciousness at all. The experience of the presence of an ego is I think part of

conscious experience which is so familiar to most of us for so much of the time that it's very hard

to imagine consciousness without ego. But I think it's entirely possible. It may not happen very often

but I think it does happen. I think it can happen. And I certainly don't think there's any conceptual problem

with thinking about something being conscious without there being an ego. Whether it happens in practice is a different question

Even then, I think the answer is yes, that it does. Great. there's some yeah questions

at the back before I was going to miss yep yeah yeah

leather jacket yeah why are you skeptical about like asserting the dependency of life to the

consciousness because like like i work with computers and even if we reduce the brain down

to like how computers work like in an algorithmic mechanism then like human body there's a constant

influx of data all the time like the replication of it with machines like for example nowadays in

AI studies, AI research, there's machine vision, machine speech, but there's no proprioception

How is that to be replicated? And how can we design a system that is so lifelike

that is going to have the constant influx of data, and that is going to be the AGI

Why are you a skeptic on that and not so assertive on life creates the consciousness

Well, I mean, I think life is necessary. I don't mean to be skeptical of the life being necessary for consciousness

that that's the view i'm i'm kind of behind in a way but i just don't want to be i don't i want

to misrepresent it as being like something we can be 100 sure of i think it's a very

strong hypothesis that this this intimate connection between life and consciousness now when it comes to the these other developments in our yes we have machine vision it's quite it's

quite good it's different from from human vision it's no there's no sense in which machine vision

has to be conscious vision. It's just good at recognizing images and doing visually guided behavior

We can build in other senses too. Now that robotics is beginning to catch up to AI

we'll be able to build systems where there are things like proprioception

which by the way is the sense that we all have of body position

We just know where our body is in space. That's proprioception and how it's moving

Of course you can give a robot that sense to you. You can even give it the sense of its own interior

what in human beings we call, and animals we call interoception, the sense of the body from within

I think the point is you can do all of this. But do we know what all is

Because we don't have a blueprint of brain. So what is the fear of machines becoming human-like in the near future

I mean, I agree with you. Yeah, yeah. I mean, so, yeah, two different questions

I mean, one is like, what will it, maybe there are other ways of building things that are sufficiently human-like that most people don't care, right

That's entirely possible. Already, a lot of people deal with language models, and they're in the sense that they feel they're dealing with something human, sufficiently human-like already

People have relationships with chatbots and things like that. So the fact that we can replicate perfectly a human being in a sense doesn matter from our perspective because in many cases we don even care But it does matter if we want to know what the system can do and whether for instance it has ethically important properties like being conscious

Then it really, really does matter. Not how much we're taken in by it, but what's actually going on with it

So that's why I think these things are important. And just plugging on extra senses to a robot

I don't think does the trick. I think it may make it look more persuasive

but I don't think it does the trick. should we try and come to someone else because there's loads of hands in the air and i'm

conscious of time um yeah you had your hand up in the air got early yeah uh forgive me if this is

too much like the previous gentleman's one um but do you think if consciousness is so clinical from

like a a physicalist perspective do you think that undermines free will in some sense like

in the sense that strawson gets out that we're all going towards a certain point if you can map the human brain in such a way there's always got to be a question about

free will hasn't there always um it's uh did nobody get the no free will instructions on the

way in no um okay it's it's a no it's a great question and i have to say like when when i was

when i was right i i love thinking and talking about free will when i was writing the book

i thought like i can't write a book on consciousness without a chapter on free will

but it was the one I struggled with by far the most because it just combines so many confusing

things together. There's the confusion of, is the universe deterministic or not? Is there some

fundamental randomness? There's the confusion of whether our conscious experiences of causing

things to happen actually cause things to happen. And there's all that ethical and moral confusions

about, well, if there's no free will, then how is anybody responsible for their actions? And

You put all these things together and it's no wonder that people get into a horrible mess about it

But I think for me there's a way to think about free will which makes sense

which means that we have the degree of free will that we need

not necessarily the degree of free will that you might aspire to

There's a sense of free will in which consciousness sort of swoops into the brain

and causes things to happen that wouldn't otherwise happen. Takes advantage maybe of some intrinsic randomness in the universe

Loads the dice. I don't think we have that kind of free will. I don't think we need or want that kind of free will

That's a spooky kind of free will. Doesn't explain anything. We human beings, we're very complex systems

When we do something, there's a lot of causes which stretch back in time. Some of them come more from within the body than outside the body

Now, if somebody hits you, you might respond very quickly and it won't feel voluntary

But if you decide to get up and go and have a drink after this, it feels voluntary. The causes are still all physical causes

but when you do something voluntary, the causes remain a little bit within your body a bit more I think what we experience as free will is the brain perception of the causes of the actions that it makes And when the brain infers that the causes of an action come more from the

inside, they have this sort of freedom from immediacy, to use the words of Mike Shadlin

a neuroscientist. When the brain infers that our actions have this freedom from immediacy

we experience them as freely willed. Is this useful? Do we really have free will? Well, yes

our organism means that the actions we do are more constrained by what we are and I think that's

the kind of free will that we want it's like a freedom from being forced to do anything else

as much as it's a freedom to do what we want because what do we want well that depends on

what we are so if we do what we are we have the free will we have all the free will that we need

and we experience it has a utility too because maybe the next time we might do something different

i think the experience of free will is marks out those actions that come largely from within

so that as an organism we might learn from them in a particular way and do something different

the next time so that is all the free will i think that any of us actually need um to to you know

retain our dignity as human beings which is fine if you want to so do you think the the causal

processes like in the brain they don't undermine free will no i don't i don't i think so so

philosophers sometimes talk about this as compatibilism that there's a version of free

will which is compatible with the universe being deterministic and you know causal processes in

the brain the body underlying everything if you give that up then the only then what you're looking

for is either randomness which i don't think is the kind of free will that we want just like

behaving randomly or something that's a bit spooky parachuting in and loading the dice in a more

strategic way so i think free will has to be compatible with the brain being this complex

nexus and network of causes and i think that's fine time for two more questions at the front

alex o'connor the cosmic skeptic um thank you um most people think that consciousness requires

complexity. But hearing you say two things, the first about how we often project ideas of

consciousness based on our human experience of consciousness onto other animals, that might not

be what it's like for a bat. But also the way that we were just talking about consciousness

without the ego. It seems like a really weird thing to imagine, but people who've done a lot

of psychedelics, for example, have experienced that. They can't quite put it into words. So I can imagine someone who's, or something which is conscious, but has no ego

I can also imagine something which is conscious but can't see, but is still conscious. Can't hear, but is still conscious. I can imagine an organism that has no such thing as memory whatsoever, but is still conscious

And it seems that when I start taking those things away and I try to think about what I actually left with consciousness itself not some of the things consciousness does in the human organism like memory self persistence through time but just that what it like to be a thing it feels like I left with something that not complex at all but quite rudimentary and simplistic

And of course, that opens the door for its position as a fundamental aspect of the universe

because it doesn't seem so insane anymore to say that that's something akin to mass or charge

It's incredibly simple. But even outside of that, do you think that consciousness

not human consciousness or some of those things that it does but consciousness itself

requires complexity necessarily as thanks alex that's that's very i like this a lot and i can

kind of go on the bus with you up to a particular stop but then i get off at a particular stop too

we'll see where we'll see where that is i think it's a it's a really important observation that

phenomenologically which is to say the experience of consciousness the experience of being conscious

doesn't have to be particularly complex. Psychedelics can strip away the ego for human beings

There's a beautiful thought experiment, a Greek thought experiment, Avicenna's man, which imagines a man floating in the sky

and progressively every sensory modality is stripped away. And I think in the original

it only talks about the classical ones, the sight, sounds, mouth, whatever

but of course we have all the internal ones you can play the same game and you say things well

there's no site and always the question is is there still something it is like to be that

that system as you strip away all these things and what are you left with if there is

sort of pure essence of consciousness thing this is conceptually possible for sure it may happen

um and we can certainly approximate does that mean complexity is necessary for consciousness

Well, here, I think the fact that the experience might be maximally simple doesn't mean that what's underlying it can also be that simple

It still might have to have some level of complexity under the hood, if you like, to support even the simplest conscious experience

And now is where I get off the bus because the fact that experience can be maximally simple, I don't think really opens a door to panpsychism any more than having an out-of-body experience opens a door to the idea that your soul can leave your head and go and sit on the balcony

I think it's a mistake to draw conclusions from the content or lack of content of an experience

to changing your beliefs about what metaphysical position might be right I think you have to justify it in other ways

Thank you everybody, that's I think all we've got time for Give a round of applause, Anu

Thank you, Johnny Thank you Want to support the channel

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