Transcript

Hey everyone. Welcome to today's conversation, which is on the mysteries of mine, trying to gain some insight into those deep and and and compelling qualities of experience that happen inside of our heads, where it comes from, and can it be replicated, and can it be described mathematically, all these deep questions about consciousness. And we're so pleased to have one of the great world experts on this subject joining us for this conversation that is Christophe Koch, who has developed his entire career to understanding the brain, the mind and the nature of consciousness. He is a neurophysiologist and computational neuroscientist who serves as the chief scientist of the tiny blue dot Foundation, where he seeks to understand the physical substrate of consciousness in the brain. Prior to that, Christophe was the president and chief scientist of the Allen Institute for Brain Science in Seattle, where he continues to do research. So I'm honored to welcome Christophe Koch to the conversation. Christophe, how are you doing? Thank you very much. Brian. I feel very well. And this came off rowing here in beautiful on our lake union here, so I feel full of women vigor. We couldn't ask for more for this conversation. So I just wanted to preface our discussion of the mind and consciousness with just a little bit of background on where you came into this subject. Because if I'm not mistaken, you're trained as a physicist, at least at some point in your career. Is that correct? Yeah, I have my PhD in physics and minor in philosophy.

Well, I mean, I come to it like you, like every human sooner, later, comes to it. That voice inside my head, right? That the movie I see all the time, my pains and pleasures, wishes, desires, fears, dreams. How will they come into an otherwise Dead universe? You know, if you have, if you think about it with pain. So let's say your toothache. You know you have, your tooth hurts. And scientifically, we know what happened. Uncontroversially, there's an inflamed puppet generates electrical activity that travels around the trigeminus nerve gets switched over in the spinal cord, goes through an intermediate delay in the thalamus, and then finally, you know, excites neuron in the cerebral cortex, the outermost layer of the brain. Ultimately, that means some ions are sloshing around. You know, sodium ions, potassium ions, chloride ions. Why should they hurt? You know, why should anything hurt? My in my liver, there are also iron sloshing around in my liver. My liver never seems to have experience, or my kidney, or any of the other organ. The brain seems to be the organ of consciousness. So, so I mean, and that's the heart of the mind body problem. How do you go from the physics of the world and the physics of organs like the brain to two experiences, yeah. Now I share that deep sense of wonder at how it could be that the motion of physical particles or ions somehow yield inner sensations. But sometimes I I wonder, and just want to get your take on it. Do we make too much of the mystery of consciousness in the following sense, it's only mysterious when we try to understand it from the outside perspective. But the outside perspective is the very perspective that has no direct access to consciousness, and so it's going to be mysterious because of that lack of direct access. So should we have expected this mystery, so to speak?

Well, even if that's the case, we might develop tools to directly give us access to your or other people's or other organisms conscious experience, right? Who knows, in the fullness of time, given our rapidly evolving understanding. But even before that, we are still humans who yearn to understand. And you know, as you well, know, there's a school in quantum mechanics that it's called, shut up and calculate, right? Don't worry about all these problems. Practically speaking, science works great.

All of that's true, but we cannot help but worry, where does that sound come from? Where does any experience come and come from? You know, even if you're a physicist, you ultimately rely on reading. You're you're looking at a voltmeter. You're looking at a gage, right? You're looking at a cloud track. Well, in all cases, your observation is mediated by your conscious experience. So consciousness comes prior to anything else. And if we claim that science can explain everything, then it has to have a coherent, lawful, empirically testable explanation for the most fundamental fact of my existence and your existence. They mean the fact that we're conscious. And so if it were the case that consciousness.

Of each and every individual was accessible by other individuals in this sort of fanciful realm of today, but maybe it will be available in the world of the future.

Would you feel the pull of the mystery of consciousness just as strongly? Because that's not really the origin of the issues. The origin is the fundamental place that experience comes from. It would be a different universe if I can directly access other people's mind, right? Because that's the tragedy of our life. In some sense, you know you can live with someone your entire life. You can make love to them so your bodies are interpenetrating, but when you look at her eyes, you fundamentally don't know what she is thinking, right? Because all you are here thinking what they are thinking of feeling, because fundamentally, you only have behavior. You have the blushing of the skin. You have you know you can see how your how your partner responds, or what they say, but ultimately you don't know what they really feel and

with the mystery lesson, maybe not, because even if I could access your mind, that still gives rise to the questions, why do we have minds at all? And who else has mine, this little artifact that the student gave me, either the dragon? Does this have mine? Well, most people would say not. But what about this? Right? This is now beginning to be a little bit more complicated. Maybe this thing has, has mine so, so we still need to understand how does, how mind comes into the into the world, and by the way, I deal a lot with patients that have lost consciousness. So these are so called behavioral, unresponsive patient, let's say, following a stroke or cardiac arrest or major brain traumatic injury. They're in the ICU. They're alive. They're on a ventilator support, but they're unresponsive. And the SEC, the if you get that call right, your loved one is in the state, the first thing you ask, Are they are they alive? Clearly, the next thing is, are they there? You want to know, because it's so important to us and to them, are they feeling? Are they experiencing? Maybe they're in pain, or maybe

they don't have any experience. It's really critical, important to know. So if you if you're not conscious, nothing matters tonight. Brian in particular, in the early night of the sleep, you're going to go into a state of sleep called deep sleep, when you have these regular, slow waves criss crossing your cortex. You do not exist for yourself. In deep sleep, in too deep sleep, you don't exist for yourself. You still exist for others. Your sleeping body is still there, but you don't exist for yourself. And then later on in the night, you'll wake up inside your sleeping body, and you have these bizarre experiences we call dream again, then you matter again for yourself. So in some sense, consciousness is the most precious. It's the only form of true existence we have in this universe. Yeah, well, I have to say, not that we want to go down this trajectory too far, presumably, but there was a period of my life when I perhaps thought too much about consciousness. I've never worked on it as a professional, as you have, but I've certainly spent a lot of time thinking about it. And when I would go to sleep at night thinking about the transition to that place of non existence, I would become terrified, and I and I, and I would in that moment of transition, I would sort of wake up startled like almost like I was dying, you know, was the feeling. So I certainly understand, you know, that divide between us being here and it mattering and us somehow not being there, and that's the most fundamental divide between anything in the universe, a great divide of being Julia turn on. He calls it between things that matter for themselves, whether that's you and I, or a baby or my bernese mountain dog, and those things, presumably like this, that don't matter to themselves. They matter to others, like to me or to the person who gave it to me, but they don't matter to themselves. It's a most fundamental distinction, yeah. Now part of this, the mystery of consciousness, at least, you know thinking as many people do intuitively, but certainly as many physicists do from professional training, when you think about the brain as composed of some collection of particles and some configuration that we can do our best to describe using classical physics or quantum physics. It doesn't really matter, but somehow, when a collection of particles are arranged correctly or carrying out the right process or in the right structure, it yields this inner world. And it's hard to understand how particles can do that. But is that too much of a reductionist perspective to make headway on the issue? Well, that's a classical perspective I also have. I mean, you know, we are pieces of furniture of the universe. We are subject to the same laws as everything else. You know, black holes are viruses. So presumably viruses and black holes.

Don't have this inner aspect. So why do we have inner aspects? And who else has it? No, I don't think that's one particular way of looking at it. So it's physicalism materialism, right? You know, there's physics, including my body. And so the big question there, how does consciousness arise? And of course, this is the big challenge to physicalism that it's so far, despite the best attempt of Dan Dennett and and the church lands and and all these other philosophers to explain how consciousness comes about, they have not succeeded. Right? This is where it is. Not so far. We have no idea. It's as mysterious as taking a brass lamp rubbing it, and suddenly a genie appears, right, yeah, yeah. And so when you began your work on consciousness, were you approaching it from a reductionist view? It was that your starting point? And have you evolved, I gather into a different perspective since then? Okay, so I started this way back with Francis Crick.

I was, well, I was a grad student in Germany, then max funk in Tubingen, when I first met him, and then when I became a postdoc at MIT at the AI Lab, I met him again, and we spent since then. We worked continuously for 16 years, and we both started with the assumption that consciousness has to be explained. It's a real thing. We didn't buy in any of these attempts of philosophers to gaslight us. That's essentially what people like Dan Dennett, bless his soul, and other philosophers have done, they essentially gaslight us into believing consciousness doesn't really exist. You know this? This the, the, the, the phenomenal aspect. This is a technical term. The subject of phenomenal aspect, the painfulness of pain, or the pleasure. You know what makes pleasure? Pleasure? What makes space extended, what makes a moment in time flow? Those things don't really exist. We're just confused about we said, No, that's wrong. This is obviously BS. It's the most fundamental thing I need to explain. But we're also scientists, and we've worked we've done very well, both individually as well as collectively, but by doing reductionist science. So can we use that same approach to identify? Firstly, it's a very mundane problem.

What are the bits and pieces of the body, in general, and more specifically, of the brain? Because we now know it's not the heart, right? You don't love someone with your heart. You Love Someone with your hypothalamus or with your amygdala or something like that. So it's much better for Valentine to give you a sweet hypothalamus piece chocolate, rather than have you? Have you tried that? Have you no? It doesn't No, and I don't think it would work very well, but so which bits and pieces of the brain are critically involved in any one conscious experience, like the conversation we're having right now? As a perfect example, right? I see you. You see me. I hear you. You hear me. But we have these feet, these we hear these voices in our head. So do we need, for example, do we need the ear of to see something? Do we need the eye? No, because I can close my eyes and I can still sort of, sort of have a ghostly image of you, and tonight, of course, I might well dream about this interview, and dreams as you and we all know as real as life. I can't tell in most dreams that I'm dreaming because it feels totally convincing. So we know you don't need the eye, you don't need the ear, you don't need

the periphery, you don't need your spinal cord. Famously, right? If you're coriplegic, you can't move, you're confined to wheelchair, but you can still see and hear and dream and fear and dread and want and desire all of that same thing. There's this little brain, you know. So you probably have heard the roughly 100 billion neurons in the human brain. 86 billion is the exact number of which 69 are in this little brain at the back the so called cerebellum. So there are few people, is rare, that are born without a cerebellum. They simply have a hole there. It's called a genesis of the cerebellum. Typically, these people are delayed. They don't talk till they're much later. You know, they have various issues, but they're fully conscious. If you and I, this happens more frequently. Have a have a tumor in the cerebellum. The surgeon has to go on and remove it. People complain they become a toxic you know, they can't do this test anymore, you know, I mean, they can't do this test anymore, right? Or this test anymore, or they sound like they're drunk, and they can't walk precisely anymore. So they lose this smooth sensory motor integration. But none of them complain that they can't hear or can see or don't have, you know, can't love or fear anymore. Now that's 69 billion neurons, some of the most glorious, well known neurons, the so called purkinio cell, these fan shaped neurons are in there. Why? Why does the cerebellum not have the magic? Well, two things are interesting about it. The cerebellum is primarily a feed forward.

Structure. In other words, it's one layer upon the next layer, just like a deep machine learning networks and LLM. And also, there's not none of this recurrent excitation. So in the what's typical of cortex, the outermost layer, if you excite there, you get all these reverberation and re excitation, very complicated pattern. You don't have that in the cerebellum. In fact, I would say to first approximation, your cerebellum is like a lookup table, a sophisticated, very precise lookup table that you need for sensory motor transformation primarily, but it doesn't seem to subserve consciousness. Okay? So that gives us some interesting clues. So you can sort of argue like that, and then now you can do experiments, for instance, where sometimes you see something like this, and sometimes I use psychophysical techniques called masking, where this becomes invisible. It's still present on my eye, but you don't directly see it. So you can try to do all sorts of experiments to try to understand what is the link between the physical stimulus and actually seeing something. And thereby, you can tag the footprints of consciousness throughout the brain, and today, hundreds of labs are doing this. This is called the neuronal correlate of consciousness, or NCC Where are there the NCCS for hearing, for seeing, for for any form of consciousness. Now when you look at one of those neuro correlates of consciousness. Presumably, as you look at it, it's still as opaque as to why it yields the feeling or the vision or the sound, that inner experience, right? I mean, you there's no clue that that would be the result of whatever's happening in that part of the brain. That's entirely correct. So ultimately, what? Yeah, so in the fullness of time, this question, you know, and I had this bet, you know, with Dave Chalmers, you know, the philosophy of mind, that in 25 years from when we did this back, back in 1998 we would identify the field would agree on, these are the neural correlates. Well, okay, I was naive. That was way too short an estimate, but and I gave him, I admitted the feed, I gave him six good bottles of Madeira. But he admits this is an entirely doable empirical reductionist project in the fullness of time, sooner or later, we know that those neurons involving this mechanism, maybe even quantum mechanics, we can talk about that, although, right now we don't really have any evidence for that, but these physical things in this part of the brain, using those genes, you know, are the footprint of consciousness. But as you said, Well, why? Why? So for that, you need a theory. Finally, we need a theory that tells us from some fundamental principle, why? What is consciousness? How does it emerge? And then can explain? Okay, does the theory explain why this particular NCC is of this form, and in this animal, or in that person, is of that form? And so many people have tried to write down theories. I mean, I've, at various times, I've read through many of them, I don't know, maybe as many as 10 different variations on an approach that tries to give some

anchor to our thinking about how the phenomenal inner world can emerge. You presumably have not been convinced by any of those because for a long time, Johan and Giulio Tononi, who you already mentioned, have been developing

a radically different approach. I would say many of the others share, not details, but they all share, starting with the physical structure, looking at the computations or the signals, and trying to argue that from that, we can extrapolate to some kind of inner world, but you go the opposite direction, as I understand it. Yeah, that's correct. So,

so one of the earliest hypothesis, and you'll see all this connected Francis and quick I had, in fact, in our first paper we wrote together back in 1990

we said at the time, people had discovered, or actually rediscovered, something that people had already noted in the 1920s

that in animals, and then later on in people, whenever they are conscious of something, you can pick up this 40 hertz oscillation. So either EG, or you put an electrode into the brain of patient of animals, you can see neurons tend to fire, you know, every 20 or 25 milliseconds. You know, 40 hertz, or in the EG, you can see activity. It's also called gamma activity. And so we made this proposal, okay, maybe this 40 hertz is a signature of consciousness, okay? And that remains somewhat controversial, but let's just accept that as a fact. Well. So why should that? Why should that be true? Why not 30 hertz? Why not 50 hertz? Is it maybe 42 the the answer to life, the universe and everything else, including consciousness? So again, this so most people, what most theories want to do. They say, well, consciousness, as you.

Said is a fact has a particular function, like planning or working memory, or like global work, the global workspace. It's a particular aspect of an architecture, or there is a particular signature, like, like 40 hertz, or some, some other aspects of the brain. And so that's a little bit like taking the brain and squeezing, squeezing the brain or its function or its computation, and saying, Well, that is what consciousness is. And then you're always left with this problem. Why this function? Why this behavior? Why this this particular computation? So all of these theories, they buy into something in philosophy called functionalism, right? So in particular, this is called Turing functionalism, or computational functionalism, that essentially says consciousness has one or more functions, and those functions can be instantiated on a Turing machine like the brain, for instance, and so that once you explain that function, you explain not only why can't Why, why the brain is conscious because it carries out this function, but then you also say, well, thereby, if I carry out the same function on a computer, it's so that computer will also be be conscious.

And that always faces a hard problem, why this function and not that function? Why this behavior, not that behavior? And so we the integrated information theory, particularly of the psychiatrist and neuroscientist Julia turn on. It takes a very different stance. It's much closer in spirit to Leibniz or maybe Spinoza.

It starts out from consciousness. It says you have consciousness primary. You have to start with the fact that consciousness exists. It's just a fact that you and I know, and every conscious being no and then you have to say, well, what are some of its properties that any conscious experience has to have, no matter you know, whether it's out of body or under psychedelic or near death experience, no matter what the experience is, it has to be. It exists, intrinsic for itself, for this conscious system itself, it is specific. It is whatever it is. It's so it's not vague. It's very specific. Even when I'm driving in the fog, you know, in the mountains, it is very specific a foggy landscape that I'm seeing. It's integrated. It's holistic. It's one. It's not two separate experience.

It's structured. For instance, in this experience that right now we have, there's left, there's right, there's up, there's down, there's distance, so it's highly any experience is highly structured. And then,

and then it has as very specific content. It's definite,

okay? It's not indefinite. It's very definite. There are things right now that are contained in my experience, particular visual and and auditory, although I can also transfer my attention to my body and I feel now, if I wanted to the chair, you know, I'm sitting in a chair, but typically I'm so focused on our conversation that I'm not aware of that. So it is that definite experience. So then the theory takes one additional axiom. It says it makes a very specific statement, which is extremely unusual. It's it has a statement about existence. What exists. This goes back to a comment by Socrates in a Plato dialog. What exists has to have causal powers. Okay? So the idea is, if I don't have causal power on anyone, nothing can make a difference to me, and I cannot make a difference to anything else, and I may as well not exist. To the extent that I have causal powers upon others, the more I exist and consciousness, according to it, is causal power of a system upon itself. What I mean by that, you take a system like my brain, or like a computer, or like a sun or any other physical system, and it's present in its present state, it has a certain if it's a lawful system, it will move to the next state with some degree of regularity, or it comes from its past state to the current state with some degree of regularity. For brains, that's highly, highly regular, because our brains are highly structured, they have lots of causal powers that instantiate it in the axons and the neurons and the synapses and all of that. And so the theory says any system that has COVID power upon itself is conscious, and if it obeys those five properties of of of consciousness, it's an intrinsic, it's specific, it's definite, it's it's one, and it's structured. Then that that that system is conscious. What is it conscious of? The theory says you have to unfold its causal powers. You have to look at all of its individual paths, let's say, its neurons or transistors, and try to understand the action of those two transistors on that in the next step, and those 10 neurons on those 50 neurons and.

You have to do that exhaustively. And if you, if you unfold that as it were conceptually, that is what the conscious experience is. It's identical. It's a very strong claim. It's an identity claim that my conscious experience maps one to one on the intrinsic causal power of of its substrate, in this case, in the brain, and it also assigns a number with that. It's called integrated information. It's a number phi, the Greek number phi, that can be between zero and an arbitrary positive number, if it's zero, the system, strictly speaking, doesn't exist for itself. It's fully reducible to a set of smaller systems. The bigger it is, the more irreducible it is. It's another way of defining what a whole is and what a system is irreducible. And the bigger the number, that's the quantity of consciousness and the qualia, the way it feels, is this unfolded causal effect, power. This all sounds very airy fairy. I fully well understand. You know, obviously

everyone watching should know everything that you're describing has been laid out in mathematical detail and research papers, and I've read some of those papers and done my best to try to grapple but I think the audience is getting the gist of it, obviously, from what you're describing. But a couple questions occurred to me, which causal power seems to be essential to the program. And as a physicist, of course, when I think of causal power, I think of the fundamental forces that we're aware of, gravity, electromagnetism, strong, weak, nuclear forces and so forth. So the causal power that you envision, or actually, I should say, require consciousness to exert. Is it exerted through those fundamental forces? Is it separate from No, no, no. So, so you know. So if I have two particles of mass, they exert causal power on each other, but not on itself, on each other. So in my brain, causal powers instantiated, as I said, by primarily electromagnetism, classical physics, right? You have electrical fields, you have gradients, you have diffusion ion spine, right? So it's all physics. So the causal powers are instantiated by the physics of the particular substrate, presumably primarily classical physics, but they may also we can talk about that may involve quantum mechanical and phenomena. So just so I understand so

when you think about consciousness in, say, a human brain, you know the one example that we're most familiar with, you do not envision consciousness preceding or existing independent of the substrate. Right Is that a correct statement without the substrate? So let's be very clear on this within IIT, if you have no substrate, there's no consciousness, and IIT takes no specific ontological state position on what type of substrate. It's very operational. All it says there are some stuff, brains, whatever, hydrodynamic, whatever. And I can observe and manipulate. So I can observe these states and I can manipulate, but using, you know, electrical electrodes or chemicals or drugs or whatever. So it says, any substrate that I can observe and manipulate I can imprint, in principle, to fully define the system using its transition probability matrix, in principle, in practice, you know, it's like it, you know, I have to fully characterize the system. But you give me a system at some level of granularity. And I say, Okay, at this level of granularity, let's say neurons, for the sake of arguments. And now I write down the complete transition probability matrix of the system. Okay, you know, these five neurons are on at time t, then at time t plus one, those 10 neurons will be firing, and then at time t plus two, those neurons will be firing. Then I can, in principle, and you can download, you know, from the website integrated information theory.org, you can download code that will precisely calculate To what extent is a system integrated has an phi different from zero, and in principle, to unfold its causal power. So there's, there's not, in that sense, there's nothing magical. Woo, woo, about this, of course, it's a theory. It may be wrong, but there's nothing. It's all very concrete, expressed in operationalized terms that as a physicist, you know, you're very familiar with so when you say that, you start with consciousness, that's not committing in philosophical language to a distinct ontology where consciousness is somehow among the fundamental ingredients or entities. Rather, it still is the physical stuff that physicists like me would talk about, but no

because no textbook of general relativity.

Or quantum mechanics, except maybe in the very end, as a footnote, talks about consciousness. General relativity doesn't talk about consciousness. Quantum mechanics doesn't talk about it, outside the measurement problems, right? Chemistry doesn't talk about the biology doesn't talk about it. But here we are. We all conscious. So no, this is, I mean, you've exactly put your finger on it. This is the this is the problem that that that you assume that first and what exists and foremost is stuff, matter, energy, space, time, and then somehow consciousness emerges in ways that we have no freaking idea how from it. Or do you say no, firstly, at least from an epistemic point of view, what I know about, you see, I don't know about atoms, right? You don't know about atoms or black holes. I have to infer them by reading textbooks, by doing experiments in, you know, 101, undergrad physics lab called the one I that the only thing I directly know about, as philosopher said, The only thing I've direct acquaintance with, is seeing, is hearing, is dreaming, etc, so that through purely empirical forget about philosophy, that has to be my starting point. That's the only thing I really know for sure, remedy, card, COVID, so

But if, if consciousness is exerting its causal power through the physical ingredients that instantiate it. So if you're not introducing other forces beyond we don't know that. We know all the forces. But for argument's sake, let's just talk about the four that we focus upon. If consciousness is exerting its causal influence through those forces, is it? Where am I going wrong if I think about consciousness as emerging from the ingredients when they're composed or structured or organized in a manner that gives a significantly large value of phi, significantly large value, well, then you're adopting dual, dualist language emerging. So that's a little bit like the Holy Ghost, right? So we have the waters of the brain, and then you do something, and they light up, you know, the brain is the most complex piece of Active Matter, and then a bubble emerges, you know, feeling of pain or pleasure of seeing you. Okay? But now you have to what's the relationship between this, this, this thing, is it? It's obviously different from the underlying brain, right? My brain isn't there's no light in there. It's pretty dark inside my skull, right? So, but here I am. I'm seeing things. So it seems to be something very different, right? And then you ask the question, well, how does it relate to matter? And is this really the old Cartesian okay? There's material stuff, you know, has extensor, anything that has extension, generalized to modern physics, and then there's cognitive stuff. So then we're really talking about a dualist viewpoint, which many, most people, have had throughout most of history, right? But most scientists are very uncomfortable with philosophers, because then you get the, what's called the interaction problem. How does this mental stuff interact? Go back from the mental to the physical to make me, for example, raise my hand. That's. How can I do that? Right? That's and in fact, this was pointed out to Rene Descartes in his correspondence with the princess of Bohemia. She pointed this out to him already 400 years ago. So that's one way. The other way is to express some sort of can

some sort of idealism that may be so. So you ask the metaphysical question. So we just discussed dualism that said, essentially two sorts of stuff. There's physical stuff and there's mental stuff. Physicalism says, of course, the only thing I really exist is physical stuff, although we can talk about it, what the physical is has gotten very complicated, right with ERP and, you know, entangled belts, pen, all of that. What is the physical? It's certainly not my grandfather's materialism anymore, right in the modern world, or you can say idealism, maybe. But this is now beyond IIT, maybe what truly exists. The only thing that you and I are familiar with is a mental and the physical. This stuff, or this stuff, ultimately, is a manifestation of something mental. This used to be a very big, you know, many people believe this. You know, Schopenhauer is probably the most And Hegel in the European tradition, the most famous philosophers associated with it, and is now, strangely making a comeback in philosophy of mind. Now I know you're not a great fan of categorizing integrated information theory, but since you did raise those various historical ways. Where does IIT fit in that categorization? Well, it shares intuition with both panpsychism and with idealism and with dualism. But it's neither. It's a scientific theory. It can be proven wrong if, if, if, what I'm conscious.

Of the neural the neural substrate, the NCC, is not the maximum cause effect power, then the theory is wrong, but it shares with time cycles and the inside that many systems beyond us may be conscious. In fact, consciousness may possibly extend through many parts, or maybe even all parts of the tree of life, because even if you look at a single cell, Brian, if you look at a single cell, parame, there are roughly 10,000 different proteins,

8000 genes, et cetera, probably billions of individual proteins interacting in an amazingly complex way that no one so far has ever managed to model. Well, that's a lot of complexity, a lot of causal power. So maybe it feels a little bit to be a cell, and once you put antibiotic on there, on the sound, the cell membrane dissolves, and the permits dies. It doesn't feel like anything anymore. Or maybe it goes even down further, maybe even in the limit, into, you know, little particles, you know, nucleons, for instance, have a phi that's a little bit different from zero, just like it, there's a little bit of heat in outer space by 2.75 degree, degrees Kelvin. Maybe there's a little bit of phi. So it shares, it shares intuition with that. But it is also different. For example, IoT says, very specifically, a dune. You know, if you take a huge mountain of sand, that Dune, or piece of furniture or this, yes, it may be true that the individual atoms have a phi that's tiny bit different from zero, but just putting a collection of those particles together does not make consciousness does not exist at the level of this dragon, my liver, although the individual cells may in isolation, may be conscious. Once you put a billion of them together, or 10 billions to form my liver, that liver does not automatically, because it's an aggregate, does not automatically acquire consciousness. It really depends on the on the causal interaction among the aggregates. And most aggregates are simply aggregates. They're not conscious by themselves. It shares some features with dualism. In a sense. It says, yeah, there's this intrinsic the inner view. So things like brains have inner view the way it feels like and have an outer view, like, you know what an outside scientist can tell, but it's different from that. And it says, Yeah, you can study the brain using good old physics, but it's not identical with physicalism. And so when you though, speak of the key property of this causal power, if you take a system that has a small amount of phi, but non zero amount of phi,

would you say that I'm able to fully describe the behavior of that system using my third party perspective, using the laws of physics as we know them, or as they will one day be formulated. Let's not commit one way or another. Is that enough to describe the behavior of that system with a small amount of phi, or does the small amount of consciousness yield a small amount of causal power that somehow I need to take into account to understand the behavior of this system. It's a latter. It's that system, if it has sufficient causal power, so it exists as a whole with phi different from zero, even small. It feels like something to be that system. Now, in principle, if you have an exhaustive description of this system, you may have read these days, people managed to obtain the connectome of the fruit fly, right? Was in well, you know, from page New York Times, 140,000 neurons. Okay, so it's a tiny fruit fly. Most people don't think about it. It's what, you know, one of the best studied model organism. It has 140,000 neurons, and presumably that then the in the central body of it, the center part of its brain, called the central body, is amazingly complex. And because it grew up under this evolutionary pressure, it has to fly. Its neurons are vastly more compact and incredibly complicated compared to the human brain. Although the human brain is much bigger, I'm pretty confident that that connectome will yield a phi different from zero. So in principle, if you have a connectome, in principle, at least you can compute it what it is experiencing, presumably something simple about vision, optical flow, about, you know, its food, its need for food, but it also has oxytocin. These insects also have some of the hormones like we have, like oxytocin, etc. So it may feel good on some days when it's in the sun, it's just fed, and may feel bad on other days. In principle, you could derive that from an exhaustive description of its brain. But if I'm looking at a simpler system, because that wouldn't be wonderful if we could actually do it, do the calculations, but it's beyond anything we can do. But for a simpler system with a small amount of phi integrated information theory would predict that the laws of physics would make wrong prediction.

Options for the behavior of that system, because the laws of physics don't take account of the causal influence. Oh, no, no, no, no, no, no, no, no. It doesn't conflict with physics. Physics would predict certain things would happen and and, but it would leave out what it feels like to be that I see. So the causal, the causal influence that you're talking about is purely internal. It has no external manifestation in a system with non zero phi, no in my case, for example, I can talk about it so clearly, in my case, for big brains, like I said, can reflect upon it. The fact that we can have a conversation about consciousness, right? Clearly means that consciousness affects my behavior, and you have to explain that now you can, in principle, you might well be able to explain that just assuming I'm an automaton and not assuming anything about my inner state, just doing, you know, good old biophysics, tracing back all the causal influences, I don't think that would be feasible, right?

Except if you know about motivations which are partly conscious, partly unconscious, etc. So you raise an interesting question. I haven't really thought about to what extent if you don't know well, I mean, one fundamental problem is one of the earliest experiments I did when I worked for a program in grad school to make some money. I programmed this labyrinth with with fruit flies, in fact, with flies and they came. They had to go in this labyrinth with all these branch points. And what you see, the fly comes to a branch point. Let's say 20% go left, 30% go right, 20% sit and the remaining what is it? 30% turn back, and it's impossible to predict. Given, you know, all the indeterminacy and all the noise, what each animal will predict will actually do so in practice, there are fundamental limits to even the simplest of all systems, you know, leaving aside, of course, Heisenberg and quantum mechanical indeterminacy, there's fundamental limits of what you can predict. So I'm not saying IIT predicts anything at odds with physics. No

physics leaves out this aspect of reality. But what's confusing to me is, if we look at a continuum of systems, or it doesn't have to be condemned. Just look at a sequence of systems from you or me. We have a large value of phi, and the causal influence of consciousness allows us to do all sorts of things. I mean, consciousness is really manifest in our external behavior. As we go down to smaller and smaller values of phi, that external manifestation is still there. It just becomes less and less. Yes, but there should be a system that we can calculate what it should do based on the absence our assumption of the absence of any phi or inner world, any conscious you know power, we should be able to predict how it behaves, but that should differ from what you would say, because you have an additional influence that we're ignoring. Well, the question is, is that causal or not? Let's take a problem closely related that free will. Okay, yeah, in fact, that's where I was going with this. Okay,

so IIT says you are free for certain types of decision. If you step on my foot and I instinctively pull my reflex like pull my foot back, that's not free will, right? If I'm drunk and do certain things, that's not free. But in the typical Free Will scenario, let's say you ask me a question, Brian, who are you gonna vote for? Okay, let's see. And I think there's a and there's B, and, you know, a does this, and I don't like B because of that, and then I come to a decision, okay, that's classical free will. Then I make a decision for whatever reasons, bias, conscious, unconscious, I make a decision. So it says that is as free as it gets, because the actual actor of the Free Will are the intrinsic causal powers. Now you can cover it. To get back to the physics. If you're just a physicist, you can say, well, I don't know about intrinsic causal powers. All I can say, if you push that button 200 milliseconds before I can see this part of the brain go up or that part of the brain go down. Sort of the libid type of experiment, yeah, okay, which is true on average, of course. But

what do we teach our students? Correlation is not causation. Correlation is not causation, right? Just because you can That's true before I make this decision, other parts of my brain turn on or turn off. That's entirely true. It has to be like that, of course, because it's not suddenly, you know, my conscious decision comes out of nowhere. But the real causal actors are sort of the intrinsic causal power. So it's called an intrinsic intrinsic powers

approach the intrinsic powers. That's where the causal action happens, although you.

A physicist, you can clearly trace entire chain of events in principle, not in practice. Of course, you can trace the entire chain of events back to, you know, 200 seconds before, 200 milliseconds or one second or 10 seconds before. But if I know you're again, we're talking hypothetical here, just so. But these are real important issues, even though they're hypothetical, not things that we can carry out. But if I knew your your quantum state, or if we're willing to just talk classically, because I think we agree that quantum mechanics is probably not of the essence to anything that we're talking about right here, because if it's a random outcome, that's not what we call free will and all that sort of stuff. So to avoid those issues, if I knew your state at a given moment. You know, going back

hundreds of years, we've had this notion that if you know the state and you know the laws of physics, you know what's going to happen, there isn't anything else that intercedes in the lawful progression of, say, your particles, from this moment in time to some future moment in time. And if that's the case, it's really hard to see where this freedom of will that you speak of has any causal power, because it's just the laws of physics acting themselves out on your particles. I do understand, though, if integrated information theory says, whoa, whoa, whoa, whoa, there's something else going on here. It's called the causal power of consciousness, and it really does influence how things unfold. So you physicists are missing something if you just analyze at the level of the ingredients and the laws that allow those ingredients to evolve. So is that the way that you would describe how we would fail to truly understand, how you would miss identify the true causes of action. The true causes of action is not my supplement. It's on the classical lipid experiment. You know, you're watching a clock around, and whenever you feel like it, you raise your right hand, and then, you know, he tracked, he did some nice psychophysics. He found well up to one second before you raised your hand randomly, you could see the signal in your, in your in your prefrontal cortex. So of course, this is not a truly free this is a random decision. Right to your point, but, but, but I think I grant that point, but it means you've identified some cover, some correlate, but not the true cause. So this is a difference between correlation and the true cause of a system, and that physics, in this case, would simply miss, because it says, well, it's only physics going on. There's nothing else, and we're not saying there's any additional laws. Would we differ in the predictions that we might differ in the explanation for why you chose to go right versus left, or to raise your hand or not as you're describing it, we would miss the true causal power of consciousness in yielding that outcome. But would we get the right outcome? If, like we talk classically, would physics be missing anything? And it goes back to the question of, you know, small number of particles with a small amount of phi, if you tell me that a small amount of phi, that if I don't take that into account, I'll make the wrong predictions. No, understand no to first order. I mean, our brains are relative determinate. Look if you know me, or if you infer something about me and what I do and where I live, you're going to be able to predict fairly accurately how I'm going to vote, okay, but I mean 100% accurately. I mean hypothetically on a mechanic to the side. Well, I mean no, but practically no, no. Here we have to go back to limits of computation. We know that is simply not possible because, you know, you get chaos and in biology, I mean, this is the big challenge with with biology, it's almost impossible to accurately compute to predict anything or any sort of behavior, and even the simplest of all organisms, right? Let's see C elegans around work. I sort of see those as practical limitations committing at academic limitations. Yeah, are we actually missing? In other words, I'm a strong believer in the absence of free will for the standard reasons, really that when I look at you, I see a large collection of particles governed by physical law, and I know that you, Christophe, do not have the power, I believe, to intercede in the lawful progression of those particles, and so you think that does it again. So

did you just violate the laws of physics? No or, or could I have, in principle, known that you were going to do that if I understood the state of your particles and could do all those calculations, yes, in principle, yes. But you could have correlated, but you wouldn't have identified the two causes of it. Got it. Got it. Okay. So I think we actually have a similar view, because I use different language, but I like to say there's different layers, different levels of analysis. Some are more useful than others.

Is the rock bottom reductionist account. Is a perfectly fine description. And right there we see the absence of the traditional notion of free will, because if it's all particles governed by physical law, there's no way for us to intercede. And then there's a higher level description that's more useful, where we do talk about human motivations and desires and perspectives that influence what our brain is thinking, and therefore the conscious choices that we make, but those conscious choices are not as free as our intuition would suggest, because of this physicalist reductionist account, is there something in that that you I would say they're not as free because we are. We are strangers to our mind, and we simply don't understand the vast amount of unconscious biases. I mean, this is literature says, right? We're biased in all sorts of ways, useful or not useful, functional or dysfunctional. We're not aware of that. So that's why I think we are, we are less free, but we are free, I believe. And it's, it's, you know, you can take an American, you know, the American Philosophical traditional pragmatism,

right? If it helps me to lead a happier like, look, we are not going to. So I think we, you and I both agree that physics, in principle, can can predict things, okay, but I would say it's not. It would leave out the two causes. You say, Well, it practically speaking, doesn't matter. Fine. So then I'm free to choose to believe in one or the other, and to me believing that I'm actually the agent of cause, that I can make a difference in my life, that I'm not, you know, the helpless victim of unseen, systemic forces leads me to be much more happier in my life. You're here. I agree. I agree completely. But let me just change gears for a moment, though. So you described information integrated information theory a little while ago, and all of the

aspects of the theory are eminently reasonable and comport with our own introspection of how it feels to be a human being and how our minds seem to function,

is introspection a dangerous tool to use. I know it's our only tool, so don't get me wrong. But for instance, you have described and if we can go there, if you're interested and willing your own psychedelic experiences, where the introduction of a little different molecule totally changes your experience in your introspective so does that suggest that we should not put as much weight on our inner assessment of how the mind works?

We have to be careful in doing it, yes, because we know our in the visual system, it's extremely well explored. There are all sorts of visual illusions, right? I can show you things and you what you see is not what's there and what's there you don't see. So we know that, right? 100 Years of visual or sensory psychophysics, but we also cannot neglect them, because then we neglect the central aspect of my life that I'm conscious. Now, if you uncomfortable with that because you like to have objective only third person, then fine, but then you're going to live in the universe that leaves out everything, everything really important about life, including your own life. If I tell you, Brian, look, here's a billion dollars I'm gonna take from you. It says gamble was a devil, right? I'm gonna take your consciousness from you, but you, you'll be able to enjoy all the money, all the power you have, but you won't feel anything. Okay. Would you take this bargain?

Hello, no,

well, perhaps you should ask my wife, but, but yes, no, I certainly would not, would not take that part. I mean, I don't know anyone, really, because this is ultimately what life is. It's, it's a feeling of conscience is it's a feeling of

of life itself, yeah, so yeah, but you have to be careful. So for example, when it comes, in fact, talking about psychedelics. Why do people do psychedelics? They do psychedelics because they'd like to explore their consciousness, and they like to expand their consciousness, and they'd like to explore different states of consciousness. Again, this is not, if you don't believe in consciousness, this is not easily explainable. It's not many psychedelics are not like it's not like cocaine, you know, or some of these other opiates you know, which, which give you this pure jolt of pleasure. You know, they don't give sometimes a like Ayahuasca is associated with purging with you know, you feel sick for the first two hours, so then they're not so much pleasurable as revelatory. Or they can show you very different aspects of your conscious experience. That's why people take it so in each case, you have to be careful.

But it's still and many scholars have raised this question going all the way back to the doors of perception by Aldous Huxley, or even another 60 years earlier, the Varieties of Religious expectations came.

Yes, can these extraordinary experiences that some people so called mystical experience, that some people have had without any molecules. In fact, Brian, have you ever tried breath work? I did, I went to an institute once where that was one of the activities. And I letting go is very difficult for me, so as I felt myself sort of leaving the usual control, I stopped. And so this is definitely an issue for me, and one that, frankly, I would like to go to the places that you describe, and maybe at some point I will go further than I have. But yes, I'm aware that you don't actually have to have any molecule. Yeah, all it takes, I just did this twice the last two weeks. It's amazing. All it takes is a circular breathing, yeah,

for sure, 10 minutes, and after 10 minutes, you start getting dissociative. And then do another five minutes, and you reach these ecstatic states where you totally lost your sense of self. I just how I'm just this one. I love to channel dogs and wolves. You just howling. You just feel it. One with the universe without any drugs whatsoever. Okay, so, so, and it's pretty lawful, you can get it in both. I mean, many people you can get it's not that, it's not that everyone has a radical different expense. So that tells you there is something trustworthy about these intuition. If you and I do the same thing and we get similar expenses, not the same, but very similar, then I can stick you in a magnet, or I can put eg electrodes on you. I can see which part of the brain are activated or de inactivated, etc. So all of that solidifies my belief in intuitions in the right way with proper courses are incredible valuable. And what do you think those intuitions in psychedelics or in breath work, or, you know, in, you know, vigorous, energetic drumming or dancing or twirling? I mean, there are many ways that people have tried to access a different state of being. Is it telling us something? I mean, some would claim that it's telling us something about deep reality. I tend to think of it. It's telling us something about how this thing inside of our head responds to different stimuli or different amount of oxygen or different kind of, you know, physical activity, but you haven't been there yet. That's true. Yeah. So where do you come down? And that makes all the difference. Yeah, that makes all the difference.

There's this example of in cognitive, in the philosophy of mind,

of Mary the color scientist. So it's a little bit variant. I know that one well, yeah, so I'm telling you a variant. So imagine we all live in a black and white world. There's no color, okay? And then for two hours, or let's say one hour, I do something, I breathe fast, or I take up psychedelics, and I see the world in color. I see yellow, I see blue, I see these colors? Okay? And then after an hour, it's gone again. Now you can say, well, sorry, Christophe, there was your brain on drugs. Or you can say, no, no, no, there is something with the world. There's really something with the world. There's nothing colored surfaces. Have it independent of the illuminating light source. It's really there. And people say, no, no, no, it's just your brain on drugs. Okay? So that's the situation I find myself after I was sitting on a beach in Bahia under the midnight southern sky, and suddenly I I accessed what Huxley calls mine at large, which I'd never really taken Seriously. I never thought about really seriously, and I knew indisputable William James calls it Nordic knowledge. You bring back this knowledge. And I know something two years ago, that's how the world is, that's the ultimate reality. Now, of course, I could be deluding myself and all of that, all of that's true, and you don't have to believe it. I get that. But for me, it is I have experienced this, this the reality that analyze everything, and now the challenge is, because I'm still a thinker, I'm still a scientist, trying to reconcile my science, you know, the thinking skills, whatever thinking skill I have, with this very unusual mystical experience. Well, I mean, it's not so in terms of mystical experience. I just attended in conference in Philadelphia, where half the room had had similar type of mystical experiences, right? There's now big literature on this, on mystical experience, with or without psychedelic dress work people have under all sorts of circumstances, and so we, I think it behooves us, to try to understand what type of what type of metaphysics is called for? That doesn't say physicalism hasn't worked. Physicalism has worked spectacular well, but it's just very narrow. It only has a very narrow lens and leaves out a lot of of other things. And so maybe.

We can come to much larger, much better picture of reality. And look, I'm not by any means, any of those scientists who, you know, look at or hear things of that sort and want to sort of push it aside as somehow mystical nonsense or something like that. I've not had the psychedelic version. I've had various moments here and there from other substances and also from nothing at all. I was once sitting in a Starbucks, and I was overcome with the strangest sensation that somehow I loved humanity, and I've never had a feeling like that before. I've never had it since, but it resonated with things that I've since read about, where some people under the influence of certain kinds of unusual stimulation from psychedelics or otherwise, have that sense of oneness. And so momentarily, I've felt it, but I've always come back to thinking about it as something in here as opposed to something out there, and maybe that's an unnecessarily small interpretation, because I've not had the fuller experiences that you're describing. So you've never lost yourself.

Well, there's one, there was one instance I've already I won't go into detail. I spoke about on Joe Rogan and experience in Amsterdam, where it wasn't psychedelics, but it was very strong for me, because I don't do any drugs, I don't drink, that certainly took me to a place I'd never been before, which was terrifying. I will never do that again, because I lost all connection to reality as I knew it, I felt as though the world was disintegrating around me. I felt like time itself was fractured. I'd look at a clock, I think in I think like 10 hours had gone by and like 10 seconds had gone by, and so different, but yes, unusual in terms of comparison to everyday reality,

okay, yeah, that that would count as a because I think it's a necessary but not sufficient condition for having mystical experience you need. I do. I do imagine, do imagine doing it. So how has your psychedelic experiences, I presume, is more than once, or

are they influencing your scientific investigations? Well, so a you know, so, you know, I just recently did this book. This title comes from the the opera Tristan is older Richard Wagner, when the second act, you know, they've drunk this love potion, and now they want to merge with each other, because they realize, you know, he, of course, famously, also wrote his own libretto, his own story, that Tristan is still Tristan, but wants to be sold and is older, is still, is old, and wants to be Tristan. And then they essentially, under the most rapturous music in the Western canon, they become one and become one was the universe. So they have a classical mystical experience,

and that's sort of what I had. And so the challenge I now have, you know, I read a lot of of, you know, the relevant literature to try to integrate this experience I had with everything else I know, including with, you know, brain science.

As I said, many people have had them. They have some degree of of lawfulness, like you know, there are certain conditions that typically have to be so typically, they involve loss of self. They're typically spontaneous, although there are some techniques, like breath work that can trigger them. They're typically shot short lasting and they leave this feeling of Noetic. You know that James calls noetic quality. You just know, you bring something back, and the expenses themselves feel more real than life itself, right? People routinely say, oh, yeah, I've come now to the heart of things. This is really what it's all about. It's like you have sort of, you know, you have a function in your brain that computes the expectation and the difference between what I actually encounter in my expectation, like, you know, some free energy principle. And now here you add an absolute minimum. This is what reality really is. And then you get back in everyday reality, and it doesn't quite feel the same. And so can we have

views of the universe that are compatible with that? And we can, there is, for example, this, have you had on your show Bernardo Castro? No, not spoken with him? I know. I know of him. I don't know him personally. Okay, he's very eloquent. So after my experience, I was so struck. I mean, I really felt that sort of, you know, this was last year. So I was, you know, 66 at this point in your life, your your ontology is pretty well established. You know, what you believe. But in 10 minutes, all of that changed. The the the, you know, the plates of my, of my ontologically underpinning suddenly gave way, left me in this morass, and I went.

It out and spend three days. So he's a Dutch computer scientist. He has two PhDs in computer science and in philosophy, and he is an advocate for for really a new version of Schopenhauer. He calls it, and he's very eloquent about it, analytical idealism. And so he says, Look what, what truly exists is the only thing we have direct acquaintance with is phenomenal, but that's the only thing that ultimately exists. And this entire world that can be studied by science, there's no question about it that follows natural laws. Again, there's no question about it. There's no god or anything supernatural involved in this ultimately, this physical world is a manifestation of something mental, and the challenge is to explain,

I don't access your mind, right? And you don't access my mind. I mean, that's why we have to talk other than directly doing some sort of mind mind meld. And why not? If there's only one mind, why shouldn't? Why should we not be able to but then under you said, in a Starbucks, suddenly you felt, you know, connected with everyone. And up psychedelics, you suddenly feel this interconnected feeling with the entire universe. So it may be on a special stage, the brain is able to access this, ultimately, mind. And so then that begs the question, what is it? Can we induce it experimentally? Can I do this in a lawful, routine way, without doing psychedelics or sitting in a Starbucks? Not that I've anything against Starbucks. It's a great Seattle company,

and so do you think that? And we've mentioned it before, but we sort of put it to the side. Is quantum mechanics at all essential here, again, many people have written about quantum mechanics in ways that I find really unpleasant and unpalatable. Investing in quantum mechanics a certain kind of conscious mystery that we who work in the field don't see within the equations at all. But for instance, if we had a classical world.

Could there be consciousness, or does it somehow intrinsically rely upon quantum mechanics? Do you have any thoughts? I mean, anybody knows, but okay, yeah, we don't know A, B, Iit certainly works perfectly well. Doesn't require any quantum mechanical substrate. It works in a classical world. And you and I agree, the brain is wet and warm, and so it's not a very likely candidate for, you know, finding things superposition, however, however, and I forgot something about that, however, anything that's not ruled out by the laws of physics might potentially be exploited by natural selection, right? That's been operating continuously for three and a half billion or 4 billion years on this planet. So, so right now with so I got together with this Hartmut Nevin. So he's the physicist, also German physicist who runs the head of the quantum compute group of Google. They built what they call Sycamore, you know, they build their 80 qubit quantum computers that, by the way, operate at 25 milli Kelvin. So that's 100 times colder than outer space, which, of course, is, you know, another 100 times colder than than this temperature, so 10,000 times colder. However, there's a few interesting anomalies. Like, it has been claimed that xenon, so xenon, you know, the rare gas. It has outer, eight outer electrons, so it doesn't really interact with anything much. Is an anesthetic. This is well known. This is not controversial. You can, you can use it to anesthetize people. It has some advantages, but it's also very expensive, and it causes people to get to get nauseated. So that's a drawback, but the claim is that xenon, 128 129 132 and 133 so different isotopes that all have the exactly same eight outer electrons

have different anesthetic potencies. Okay, and curiously enough, the ones that have low anesthetic potency have spin one, nuclear spin one half, and they the other ones have spin zero. So we are currently doing with collaborators at in Santa Barbara and in Buckinghamshire in England, we're trying to test in flies and in human pluripotent stem cells, as well as in primary culture. Is this good? Is purely empirical question? Is it true that Xenon isotopes have differential effects on the ability of these biological these neurobiological systems, to be anesthetized? I see if they do against purely empirical question, it would be a real head scratcher, because it's not clear how nuclear spin. It's totally, you know, inside the nucleus, totally shielded by all of its electrons. Why that should matter? So until, I think it's unlikely they're not given the wet and warm brain. But we can't rule it out right on.

And another question that I just wanted to run by

you, when you calculate phi, the integrated information for a given system, you were saying that many systems have zero, if it's, you know, just particles floating through empty space, some have non zero. If there's a certain kind of structure there, our brains have higher values. What about systems that seem to be not conscious, but are artificially imagined or constructed? I think Scott aaronson wrote down one or something where the value of phi is really big. Do you interpret that as this system that you know, whatever is a collection of circuits, I forget the details that he wrote down. Do you view it as having consciousness in inner world? Well, if it is true, yes, however. So the particular transformer architecture, this matrix architecture, Scott Allison proposed, would be very simple. It could just be spatially extended, but vast,

it would just feel spatial extent. So it would be like looking at a totally empty black, black or blank wall that has no content whatsoever. Yeah, this is entirely possible. I mean, look, you know the theory that mammals that you know, we know that whales are not not fish, but actually mammals, although it's very unintuitive, right? They swim the water, they smell fishy, but they're not fish, they're mammals, right? So this is a strange prediction, or black holes in gr and all of that. It's a strange prediction. Finally, we have to see they're more interesting predictions. So for instance,

your brain and my brain, as we just talked, I don't access your mind. I don't access my you don't access my mind. Now we can start connecting. We can start doing what's called Brain bridging, where I have one wire from my visual cortex to your visual cortex, from your auditory cortex to my auditory cortex, etc, and then I add more and more wires. So at some point I would see the, you know, it's like augmented reality. So I would see this scene, but then I would also see the world as seen through your eyes, right, ghostly superimposed. But I would still me, be me, and you would still be you. The theory says at a precise point when the integrated information across our two brains, given all the wires exceeds the phi of your brain or of my brain at that point, abruptly, you can add one axon. Boom. Abruptly. Now it's an extremum principle. I disappear, you Brian, disappear. There is this new entity, this, this amalgamation is ubermind of Brian Christoff, that speaks with two mouths, that has four eyes, you know, four legs, etc, and that would combine both your mind and my mind.

And then as soon as I cut that connection again, we fall back. And this is really the inverse of what happens in a split brain experiment. You know, we have two hemispheres that 200 million fibers called the corpus callosum that cut the left, that connect the left and the right. And sometimes the surgeon has to cut them because to prevent seizures. They still do that today to prevent seizures. And then, as far as we can tell, if, if, if I cut right now, your corpus callosum, if I divide your brain this way, there would be two entities I could typically only talk to the left one, because that's in most of us. That's where language is, not in all, but in most of us, but your right one would also be conscious. There would be two conscious entity, but then once you connect them, the integrated information here exceed the integrated information the here and there. And this is an experiment that we can probably do in a few years from now, in in maybe in in small animals like flies or maybe even my mouth, amazing, that that, that that would be amazing. And what about

artificial consciousness, not artificial intelligence? Per se? Certainly, I think I've read, and it makes sense to me that if you calculate phi for a digital computer that's attempting to simulate a brain, phi is much smaller for it than it would be for the human brain by virtue of the way that our digital computers are constructed. But you could, of course, imagine an artificial version, not a digital computer that really is based upon the way our brains operate, but is created by human beings, as opposed to by, you know, gestation. I guess we create human brains too, but not in the manner that I'm describing now, in the laboratory we could create this. Is there any obstacle, in principle, to creating that kind of an artificial mind? You're very good. No, no, it was exactly the reason you mentioned. So let's take something from concrete GPT for turbo, right, the latest, you know, oh, what is it? Oh, one, you know, the latest version of GPT. When you talk to it or interact with it, it's amazing. You know, you can ask it all sorts of questions. You can ask it, how do you feel about this? Or.

How would you respond if this were to happen? It can tell you in great detail, really stunning, right? But that's of course, because it's read all of human literature and regurgitates that right in in a brilliant way, right? It's not because of it. There's any real experiences. And why does it say that? Because, as you said, you have to look actually at the substrate, not at the simulation, right? So even if you simulate a human brain, yes, you can simulate all the connectivity, but actually you have to go under the hood, right? You have to open the hood and see, well, actually, where does the physical action happen? It happens at the level of the CPU or the TPU or ALU, where you have one transistor and the electric charge on one transistor, right, that moves to the other gates and open those gates, etc, and given the radical different architecture those things. So right now, the digital computers in the cloud are not conscious, and they won't be conscious in another 10 or 20 years. However, you are, right? There's nothing magical about the brain, right? There's nothing supernatural about the human brain. And so where we to build what's called a neuromorphic computer that some people are trying to do that follows the same connectivity principle as a human brain, or possibly even with quantum computers, right? Because if you can really entangle a million bits, and they're all intertangled, right, two to the million, that is vast connect, effective, vast connectivity. And that probably has mean depends on the details, and you have to look at the actual math, but that may have very high connectivity. So it's well possible that we can engineer systems that have actually artificial consciousness and not just artificial intelligence.

But I'm less concerned about that. The concern really is intelligence, right? Because what you can do with that intelligence, because intelligence, I ultimately about doing consciousness, is about being. It's about being, it's a state. But if you imagine these doomsday scenarios, these dystopian scenarios, where an artificial intelligence somehow so exceeds us, you know the traditional story that we become irrelevant, and willingly or not, this artificial system somehow causes our extinction. Presumably, we would be happier, if that's the right adjective, probably not, if that artificial intelligence had Artificial Consciousness too, because otherwise, the thing that takes over and maybe it creates a paradise here on Earth, it doesn't experience it. It's like that billion dollar deal that you suggested to me earlier. You know, it would be an empty world, filled with beings creating, maybe beautiful art, beautiful music, operas, but having no inner experience of it. Schrodinger, I mean, has this beautiful sentence, universe without consciousness is like a play without an audience. Yeah, no one is experiencing anything. People, there's furious action, because that's what intelligence involves. Right, furious action, but no no experience whatsoever. Yeah, it's a pretty depressing scenario, yeah? So one final question, or set of questions,

do you fear the end of your consciousness? Do you fear death?

Wow, that's

I.

I have a pretty sunny disposition. But as you get older, and this is probably not foreign to you or members of the audience, you know you can sleep as well, as you get older, and you sometimes lie in bed and wonder, you can't sleep. You wonder about what happens after I'm dead. You wonder about eternity, what that really means. And then you get this vertigo. You get this existential verticals, like looking down. I used to be rock climbers, like looking down into an abyss, but the Abyss has no bottom right, and it's really terrifying, and it's quite useless, because, you know, you don't reach any new insider conclusion, but you can't help yourself. And then I had this, this near death experience with which I opened this book. Then I myself the world. And one benefit, it was horrifying, just like your experience in Amsterdam. I'll never, ever do anything like that again. It's true. It was just horror. Well, it was a weird state of horror and ecstasy,

but it gave me the gift that I only realized, like weeks later. I realized this was in the first week of the pandemic. I said, Hey, wait a minute, I haven't had one thought about death, and I haven't had this has now been almost four and a half years. I haven't one thought. I mean, I know I'm going to die. I don't deny that, and I don't want it's not that I want to die now, but it, it doesn't bother me. I've accept, I've accepted it.

So it's a, what was it? What was it about the the experience that made the change? Well, so A, this is not uncommon. So if you talk to near people with near death experience.

Which are different? Well, they can be related to mystical experience, but very often they're different from, from, from. So it's like a Venn diagram. He has mystical and he has near death experiences.

It's not uncommon that people have this loss of fear of death. I don't know it's it's that, certainly in my near death experience, there was no crystal, there was no body, there was no self, there was no ego, nothing like that. I wasn't a person or a male or female or a child or an animal or God or anything. I just was, maybe

I can't quite explain it. One explanation is that psychologists have advanced Oh, because now you feel you see the mine at large. But I didn't encounter mine at large. This mine at large. Expense of mine came many years later, so I don't know. All I can say is a psychological fact, since my nd II have not I've completely lost the fear of death. And you do feel, though, that with death, with the end of the substrate your consciousness will end too. Is that? Is that accurate with your with the perspective you take now,

my egotic consciousness,

ego, ego, ego, Christophe will die if my brain dies, or, you know, it gets injured enough, Christophe will die, and Christophe, memory and traits will disappear. However, certainly, on an idealist point of view, I think of more now, like, you know, there's this river, and you can observe these eddies in the river, right, these little whirlpools, and they may have existence for minutes or hours or day or two, but ultimately, you know, they get perturbed, and they get reabsorbed by the water. And, you know, you're part of this, the identity is lost. Is, you know, you know, being part of this vast ocean again. So that's how I think today about what's so I'm sort of curious to see what is this too? Is this what's going to happen at the point of my personal death? But of course, I won't be around really to witnesses, because I is going to die. But since it has died already a number of times in various experiences, that's okay, too. I just I've gotten more and more tearful ever since then? Well, it's a beautiful image, this idea of eddies that momentarily form and then rejoin the larger flow of something greater. So I certainly, I certainly enjoy that imagery. So Christophe, this has been a fascinating conversation. Look, best of luck in your research, and you're both, you know, professional and personal and just trying to illuminate this mystery of the mind. So thank you so much for joining us. Thank you so much, Brian for having us. Thank you. Thank you. Applause.