Making Sense with Sam Harris - Making Sense of Consciousness | Episode 2 of The Essential Sam Harris

Episode Date: December 15, 2022

Filmmaker Jay Shapiro has produced a new series of audio documentaries, exploring the major topics that Sam has focused on over the course of his career. Each episode weaves together original analysis, critical perspective, and novel thought experiments with some of the most compelling exchanges from the Making Sense archive. Whether you are new to a particular topic, or think you have your mind made up about it, we think you’ll find this series fascinating. In this episode, we survey the landscape of consciousness and get acquainted with the mystery of the mind. We start with an attempt to define consciousness–and veterans of conversations on consciousness will know that this is a huge part of the challenge.  David Chalmers begins with his conception of what he coined “The Hard Problem of Consciousness” and a famous question offered by the philosopher Thomas Nagel.  We then construct a “Philosophical Zombie” before the philosopher Thomas Metzinger explains why he is thoroughly unimpressed by the ability to imagine “such a thing,” while he simultaneously warns us against ever attempting to build one. Anil Seth brings some hope of whittling away the intuition gap of the hard problem by pursuing the “easy” problems, with clear scientific reasoning. Later, Iain McGilchrist lays out the intuition-shattering implications of the famous Roger Sperry experiments with split brain patients that suggest that consciousness can be cut with a knife… at least temporarily. Annaka Harris then shifts the conversation to the realm of panpsychism, which suggests that consciousness is nomologically fundamental and potentially permeates all matter.  Finally, Don Hoffman explains that consciousness is not only fundamental and non-illusory, but that the physical world we appear to be navigating is merely a virtual space-time interface, which has evolved to hide the true nature of reality from us.

Thank you. of the Making Sense podcast, you'll need to subscribe at SamHarris.org. There you'll find our private RSS feed to add to your favorite podcatcher, along with other subscriber-only content. We don't run ads on the podcast, and therefore it's made possible entirely through the support of our subscribers. So if you enjoy what we're doing here, please consider becoming one. Welcome to The Essential Sam Harris. This is Making Sense of Consciousness. The goal of this series is to organize, compile, and juxtapose conversations hosted by Sam Harris into specific areas of interest. This is an ongoing effort to construct a coherent overview of Sam's perspectives and arguments,

the various explorations and approaches to the topic, the relevant agreements and disagreements, and the pushbacks and evolving thoughts which his guests have advanced. The purpose of these compilations is not to provide a complete picture of any issue, but to entice you to go deeper into these subjects. Along the way, we'll point you to the full episodes with each featured guest. And at the conclusion, we'll offer some reading, listening, and watching suggestions, which range from fun and light to densely academic. One note to keep in mind for this series.

Sam has long argued for a unity of knowledge where the barriers between fields of study are viewed as largely unhelpful artifacts of unnecessarily partitioned thought. The pursuit of wisdom and reason in one area of study naturally bleeds into, and greatly affects, others. You'll hear plenty of crossover into other topics as these dives into the archives unfold. And your thinking about a particular topic may shift as you realize its contingent relationships with others. In this topic, you'll hear the natural overlap with theories of identity and the self, overlap with theories of identity and the self, free will, mind and the brain, artificial intelligence, belief and unbelief, meditation and spirituality, and more. So, get ready.

Let's make sense of consciousness. As you just heard, the topic of consciousness overlaps with just about everything, because depending on your description of it, it's the medium through which everything is experienced. Or is it more accurate to refer to it as the experience of anything? A great deal of the effort to wrap one's head around the topic of consciousness is the struggle to define it at all. Most thinkers in this space concede that we don't yet have a good definition or explanation for consciousness. Though, as you'll also hear, there are some who think we're simply asking the wrong questions, or demanding too much of an explanation of it.

But to many, there does seem to be something special about the issue of consciousness. This particular issue and sticking point of the special case of consciousness is the issue which drove Sam back into academia to pursue his PhD in neuroscience. In fact, he was directly inspired to do so by the guest in the first clip. So let's see if we can get a hold of that intuition that consciousness is a special and perhaps perpetually intractable case. In this episode, you're going to encounter a bevy of thought experiments and whimsical hypotheticals that attempt to get at this thing we call consciousness. In many ways, all of this can sound a bit odd. If consciousness is simply the manifest truth of subjective experience itself, then consciousness

is simultaneously the most obviously and undeniably present and graspable thing there could be, yet it remains perhaps the most elusive and mysterious thing to make any sense of. How could this be? One thing that you'll need to keep in mind is Sam's firm philosophical position on consciousness. He argues that consciousness is the only thing which can't be an illusion. In philosophical jargon, this idea is sometimes called solipsism. What he means by this is that one could be hopelessly confused about what they are perceiving as reality. You could even be

unknowingly in a simulated universe generated by a supercomputer in another dimension. All of your memories could be false and simply injected into your brain a split second ago by an alien who was just playing an elaborate trick on you. You could be in a dream. But as long as there is a perception at all, that presence of perception is what Sam means by consciousness, and that feeling is undeniable from the inside of it. In a very literal sense, it is a self-evident truth, the only self-evident truth in Sam's view. In this meaning, a contention that one only seems to be conscious,

or that one is being tricked into thinking he is conscious, is total nonsense, because the seeming is the consciousness. This sets up a kind of dual picture where we have consciousness and its contents. And even if the contents are utterly confused or unreal in some sense, the consciousness remains as the thing which experiences them. Perhaps consciousness is something like a mirror reflecting passing lights and colors. The images that appear on the mirror may be illusions or tricks of shadows which convince you of a world.

But the mirror itself is undeniable. If you remove the mirror, there is nothing to capture or experience the contents of that world. But already there is something quite strange to ask. Why does there need to be a mirror at all? Isn't it perfectly feasible to have a universe that follows the laws of physics and goes along doing its thing, purely in the dark, without any inner subjective experience embedded within it, without any feeling at all? That universe is at least imaginable to us, and it feels possible and eerily easy to conceive. But before we dive in too quickly, we still need to try to point to exactly what we mean by consciousness. Sometimes conversations on consciousness can feel

like an endless string of analogies and stories trying to restart a strange deliberation on the correct path. Is consciousness like a radio receiving signals? Is it like a stage play or theater? Or is it, as Plato once famously imagined, like shadows on a cave wall? You can pay attention to what it's like to hear the sound of my voice right now and notice your awareness. And presumably, there is a level of information processing happening in your brain which somehow gives rise to the feeling that it is something that it is like for you to be listening to me right now. But your brain is also presumably doing a lot of other things at the moment, which are arguably much more important, like regulating the function of your kidneys, or

monitoring your heartbeat, or breathing. And there doesn't seem to be a subjective feeling associated with those clusters of brain activity, does there? You could perhaps direct your attention to them and maybe grasp some vague awareness. But before I pointed it out and you turned your inner spotlight towards them, the activity was happening in the darkness, without a subjective conscious quality. So why do some activities give rise to this feeling, while others don't? Let's try out our first hypothetical to further get at what might be meant by consciousness. This is a conception which very much aligns with Sam's usage of the term throughout these conversations, so it will be very useful to onboard now.

Thomas Nagel brought us a simple question in an essay he wrote in 1974. The essay asks the question in its title, What is it like to be a bat? One of the prominent voices in the field of consciousness is the American philosopher Daniel Dennett. Dennett likes to refer to these kinds of hypotheticals and mind explorations not as thought experiments, but as intuition pumps. This is itself a useful analogy where you can imagine being walked through a hypothetical not to perform any kind of experiment in any scientific sense, but to have the hypothetical sort of inflate an intuition you might have about something. Perhaps the intuition gets pumped up to the point where it crowds out all others

and proclaims itself to be an undeniable truth. Dennett happens to disagree with Sam's views on consciousness, and Thomas Nagel's as well. You'll hear some of Dennett's objections raised by Sam and his guests throughout these conversations. Sam had Dennett on the show, but that entanglement is included in the Free Will compilation. And as you'll surely gather, that conversation includes intimately related disagreements. But let's spend some time with Nagel's question and see what kind of intuitions it pumps up within us. This intuition pump is best run on oneself, so I'll start by putting myself to the test. So what is it like to be a bat? Well, it's quite different. It's dark.

I have this sonar echolocation thing. Is this a little like human vision? Or is it more like hearing? Or even touch? I must be building some kind of mental map of my physical environment as I navigate it. The echolocation seems to give me a good idea of how to move about the radial area around me to about 10 feet. I feel something. It's a sort of urge or desire, like hunger. And I experience something like sweetness and satisfaction when I taste the juicy mosquito I just ate. I don't like the feeling of bumping into the wall too hard.

That must be something like pain. I really am not sure how much of a concept of the future or past I can imagine. Do I have a mind's eye where I can picture things which are not present? Do I have a memory? Whatever this constellation of experiences is, this must all add up to a kind of batness. It feels like whatever this is, that there is something that it is like to be a bat. Now let's pump this intuition fully by substituting alternatives for the bat in Nagel's initial question.

What is it like to be a dog or a ladybug? What about a grizzly bear? All of these substitutions seem to still result in having some kind of experience in inner world. But what happens to our intuition when we swap out the bat with something like a tree branch? What is it like to be a twig? Or a boulder? Or the Eiffel Tower? What about a submarine, which also has something like sonar? Is it like anything to be them?

This was the point of Nagel's question. If imagining what it's like to be something ends up obliterating the notion of experience at all, is the thing conscious? We may not know exactly what it's really like to be a bat, but we get the sense that there is something that it must be like to be one. We tend not to have that same intuition about the boulder. Perhaps this is because there doesn't appear to be anything like a central nervous system, or a place where all the sensory data is orchestrated or stored. A simple old-fashioned mercury thermometer does

interact and respond to its environment. The mercury conducts heat from its target and expands and climbs the tube in response. But is it like anything to do this? Is the thermometer having an inner experience? Or is this just a non-sentient interaction of physics that lacks any sense of an inner experience or the feeling of an experiencer somehow within the thermometer? Our intuition suggests that this is the truer picture, and we tend not to grant consciousness to thermometers in the way that we might to bats, bears, and other people. But wait,

something funny is happening here. If I look closer and closer at my physical system, which I've already established must be generating consciousness as proven by my subjective inner experience at this moment. Am I not just made up of incredibly small thermometers? If I look at a single atom in my brain, is it not just responding to its environment and being moved around by the laws of physics in much the same way the thermometer is? How is any amount of this seemingly non-sentient activity and in any imaginable physical configuration, generating something like a unified, collective, subjective, consistent experience that we are calling consciousness.

This leads us to our first guest, who coined this particular question, the hard problem. The guest is the philosopher David Chalmers. By distinguishing this problem as the hard one, Chalmers implies that there must be easy problems to consider in this space. Don't let the word easy confuse you here. He's not suggesting that we know much about those either, but by easy problems, he's talking about the questions of how to correlate conscious states with neurophysiological activity,

such as noticing which areas of the brain light up when the subject reports experiencing a certain sound, memory, or emotion. Chalmers contends that all of that work may provide insight into how the machinery of the brain operates, and it might give us fuller scientific descriptions for things like vision, hearing, taste, or even memory and dreaming. But all the correlations we could ever hope to find in those investigations won't, and perhaps can't ever address, why any physical activity should, and apparently does, give rise to inner subjective experience. That's the hard problem.

So let's start with Sam and David Chalmers' exchange on this topic from episode 34, which is called The Light of the Mind. We're going to jump right in with Sam asking Chalmers what he thinks of Nagel's famous question about what it's like to be a bat. There was another very influential articulation of this problem, which I would assume influenced you as well, which was Thomas Nagel's essay, What Is It Like To Be A Bat? The formulation he gave there is, if it's like something to be a creature or a system processing information, whatever it's like, even if it's something we can't understand,

system processing information, whatever it's like, even if it's something we can't understand, the fact that it is like something, the fact that there's an internal, subjective, qualitative character to the thing, the fact that if you could switch places with it, it wouldn't be synonymous with the lights going out, that fact, the fact that it's like something to be a bat, is the fact of consciousness in the case of a bat or in any other system. I know people who are not sympathetic with that formulation just think it's a kind of tautology or it's just a question begging formulation of it. But as a rudimentary statement of what consciousness is, I've always found that to be an attractive one. Do you have any thoughts on that?

Yeah, I find it's a, that's about as good a definition as we're going to get for consciousness. The idea is roughly that a system is conscious if there's something it's like to be that system. So there's something it's like to be me. Right now, I'm conscious. There's nothing it's like, presumably, to be this glass of water on my desk. If there's nothing it's like presumably to be this glass of water on my desk if there's nothing it's like to be that glass of water on my desk then it's not conscious likewise some of my mental states you know my seeing uh the green leaves right now there's something it's like for me to see the green leaves so that's a conscious state for me but maybe there's some unconscious language processing of syntax going on in my head that doesn't feel like anything to me or some

motor processes in the cerebellum. And those might be states of me, but they're not conscious states of me because there's nothing it's like for me to undergo those states. So I find this is a definition that's very vivid and useful for me. That said, it's just a bunch of words, like anything. And for some people, this bunch of words, I think, is very useful in activating the idea of consciousness from the subjective point of view. Other people hear something different in that set of words, like, what is it like? You're saying, what is it similar to? Well, it's like, it's kind of similar to my brother, but it's different as well. You know, for those people, that set of words doesn't work. So what I've found over the years is this phrase of Nagel's is incredibly useful for at least some people in getting them

on to the problem, although it doesn't work for everybody. What do you make of the fact that so many scientists and philosophers find the hardness of the hard problem, and I think I should probably get you to state why it's so hard, or why you have distinguished the hard from the easy problems of consciousness. But what do you make of the fact that people find it difficult to concede that there's a problem here? Because it's, I mean, this is just a common phenomenon. I mean, there are people like Dan Dennett and the Churchlands and other philosophers who just kind of ram their way past the mystery here and declare that it's a pseudo-mystery. Let's state what the hard problem is and perhaps you can say why it's not immediately compelling

to everyone that it's in fact hard. Yeah, I mean, there's obviously a huge amount of disagreement in this area. I don't know what your sense is. My sense is that most people at least got a reasonable appreciation of the fact that there's a big problem here. Of course, what you do after that is very different in different cases. after that is very different in different cases. Some people think, well, it's only an initial problem and we ought to kind of see it as an illusion and get past it. But yeah, to state the problem, I find it useful to first start by distinguishing the easy problems, which are problems basically about the performance of functions from the hard problem, which is about

experience. So the easy problems are, you know, how is it, for example, we discriminate information in our environment and respond appropriately? How does the brain integrate information from different sources and bring it together to make a judgment and control behavior? How indeed do we voluntarily control behavior to respond in a controlled way to our environment? How does our brain monitor its own states? These are all big mysteries. And actually, neuroscience has not gotten all that far on some of these problems. They're all quite difficult. But in those cases, we have a pretty clear sense of what the research program is and

what it would take to explain them. It's basically a matter of finding some mechanism in the brain that, for example, is responsible for discriminating the information and controlling the behavior. And although it's pretty hard work finding the mechanism, we're on a path to doing that. So a neural mechanism for discriminating information, a computational mechanism for the brain to monitor its own states, and so on. So for the easy problems, they at least fall within the standard methods of the brain and cognitive sciences. But basically, we're trying to explain some kind of function, and we just find a mechanism. The hard problem, what makes the hard problem of experience hard is it doesn't really seem

to be a problem about behavior or about functions. You could in principle imagine explaining all of my behavioral responses to a given stimulus and how my brain discriminates and integrates and monitors itself and controls you can explain all that with say a neural mechanism and you might not have touched the central question which is why does it feel like something from the first person point of view that just doesn't seem to be a problem about explaining behaviors and explaining functions and as a result the usual methods that work for us so well in the brain and cognitive sciences, finding a mechanism that does the job just doesn't obviously apply here. We're going to get correlations. We've certainly got finding

correlations between processes in the brain and bits of consciousness, an area of the brain that might light up when you see red or when you feel pain. But nothing there seems yet to be giving us an explanation. Why does all that processing feel like something from the inside? Why doesn't it go on just in the dark, as if we were giant robots or zombies without any subjective experience? So that's the hard problem. And I'm inclined to think that most people at least recognize there is at least the appearance of a big problem here. From that point, people react in different ways.

Someone like Dan Dennett says, ah, it's all an illusion or a confusion and one that we need to get past. I mean, I respect that line. I think it's a hard enough problem that we need to be exploring every avenue here. And one avenue that's very much worth exploring is the view that it's an illusion. But there is something kind of faintly unbelievable about the whole idea that the data of consciousness here are an illusion. To me, they're the most real thing in the universe, the feeling of pain, the experience of vision or of thinking. So it's a very hard line to take, the line that Dan Dennett takes. He wrote a book,

Consciousness Explained, back in the early 90s, where he tried to take that line. It was a very good and very influential book. But I think most people have found that at the end of the day, it just doesn't seem to do justice to the phenomenon. doesn't seem to do justice to the phenomenon. You've touched on it in passing here, but remind us of the zombie argument that, I don't know if that originates with you, it's not something that I noticed before I heard you making it, but the zombie argument really is the thought experiment that describes epiphenomenalism. Introduce the concept of a zombie, and then I have a question about that. So yeah, the idea of zombies actually, I mean, it'd been out there for a while in philosophy before me, not to mention out there in the popular culture. But the zombies which play

a role in philosophy are a bit different from the zombies that play a role in the movies or in Haitian voodoo culture. You know, The ones in the movies are all supposed to be... All the different kinds of zombies are missing something. The zombies in the movie are lacking somehow life. They're dead, but reanimated. The zombies in the voodoo tradition are lacking some kind of free will. Well, the zombies that play a role in philosophy

are lacking consciousness. And this is just a thought experiment, but the conceit is that we can at least imagine a being at the very least behaviorally identical to a normal human being, but without any consciousness on the inside at all, just acting and walking and talking in a perfectly human-like way without any consciousness. The extreme version of this thought experiment says we can at least imagine a being physically identical to a normal human being, but without any subjective consciousness. So I talk about my zombie twin, a hypothetical being in the universe next door who's physically identical to me.

He's holding a conversation like this with a zombie analog of you right now, saying all the same stuff and responding, but without any consciousness. Now, no one thinks anything like this exists in our universe, but the idea at least seems imaginable or conceivable. There doesn't seem to be any contradiction in the idea. And the very fact that you can kind of make sense of the idea immediately raises some questions like, why aren't we zombies? There's a contrast here. Zombies could have existed. Evolution could have produced zombies. Why didn't evolution produce zombies? It produced conscious beings. It looks like for anything behavioral you could point to, it starts to look as if a zombie could do all the same things without consciousness. So if there was some function we could point to and say,

that's what you need consciousness for, and you could not in principle do that without consciousness, then we might have a function for consciousness. But right now it seems, I mean, actually this corresponds to the science. For anything that we actually do, perception, learning, memory, language, and so on, it sure looks like a whole lot of it can be performed even in the actual world unconsciously. So the whole problem of what consciousness is doing is just thrown into harsh relief by that thought experiment. Yeah, as you say, that most of what our minds are accomplishing is unconscious, or at least it seems to be unconscious from the point of view of the two of us who are having this conversation. So the fact that I can follow the

rules of English grammar insofar as I manage to do that, that is all being implemented in a way that is unconscious. And when I make an error, I, as the conscious witness of my inner life, I'm just surprised at the appearance of the error. And I could be surprised on all those occasions where I make no errors and I get to the end of a sentence in something like grammatically correct form, I could be sensitive to the fundamental mysteriousness of that, which is to say that I'm following rules that I have no conscious access to in the moment. And everything is like that. The fact that I perceive my visual field, the fact that I hear your voice, the fact that I effortlessly and actually helplessly decode meaning from your words, because I am an English

speaker and you're speaking in English, but if you were speaking in Chinese, it would just be noise. And I mean, this is all unconsciously mediated. And so again, it is a mystery why there should be something that is like to be associated with any part of this process, because so much of the process can take place in the dark. You heard David Chalmers mention the idea of a philosophical zombie and explain it a bit. But it's worth spending a little more time to fully explore this idea in order to set up our next guest, who actually finds the whole notion of the zombie to be an unhelpful distraction.

So let's build a zombie. Imagine having a cabinet full of raw materials to build a human. Picture a mess of atoms, or quarks, or however small you'd like to imagine our building blocks. Picture all of that stuff in well-labeled, pull-out drawers at our bizarre assembly station. At this stage, one would be hard pressed to say the stuff in any of the drawers was conscious using Nagel's test. It appears to be just like our initial questions

of asking what it's like to be a boulder, perhaps even worse. What is it like to be a single electron? But now let's start putting all the pieces together. And let's say we set out to build a precise copy of you. So we start putting all the atoms together, forming the correct bonds to make carbon and nucleic acids, proteins, lipids, blood plasma, and everything else.

And we construct the entire physical system that is you, forming all the organs and bones and, of course, the brain. Until at last, we complete our perfect copy. This copy of you would presumably speak just like you, and announce itself to be you. If all memory and knowledge is ultimately embedded in a physical system, then we must have also copied all of that stuff over during our building process. This clone would have all of your memories, your personality, your desires,

your fears, and everything else. And of course, we would assume the thing is conscious. It would certainly be behaving as if it were, but remember that our intuition was telling us that just a few minutes ago when all the parts were unassembled in the cabinet, there was no consciousness there. So what happened here? There seems to be only a few possibilities. One possibility is that the copy slowly gained consciousness as we assembled the system. Consciousness began to emerge when the parts were in a sufficiently complex arrangement and in a special configuration, and the consciousness began at a very low, dull level. Consciousness fully reached its current depth and richness when we completed the building of the whole body, and likely needed much of the brain to be built to really ramp up its subjective experience. Imagine this as something like a

consciousness dimmer switch being turned up as we built. Another possibility tells us that consciousness was completely absent while we were building the thing, until we added one specific piece which completed some yet unknown special configuration of information integration, and then consciousness flicked on into existence, something more like an on-off switch, or like the previous analogy of a radio. Perhaps there is something like a consciousness field which is only able to be tapped into and channeled if the receiver is built just right, just like a radio antenna picking up the already present radio signals in the air. They were always there but were invisible and mute until we completed our radio receiver. This idea is also intuitive to some people,

because consciousness feels like a binary state where you either have it or you don't. Or to recall our earlier analogy, it's either somewhere on the mirror or it's not. But there is another possibility about our clone that's also strangely intuitive, or at least conceivable, and that is that consciousness never happens at all in this process. Recall that we were quite certain that the atoms and quarks in the drawers had no

consciousness when we started, and we definitely never ladled any magical consciousness stuff into the copy at any point while we were building it. We don't even know if such a metaphysical thing exists, and if it does, we certainly don't have physical access to it. So, perhaps the copy of you behaves just like you and announces its consciousness, but the lights are not actually on inside. It's not really having any inner subjective experience. This is the idea of the philosophical zombie.

Now, if you're getting a bit frustrated by this picture and professing that a philosophical zombie could not possibly exist even if we could conceive of the philosophical zombie. Now, if you're getting a bit frustrated by this picture and professing that a philosophical zombie could not possibly exist even if we could conceive of the thing, and consciousness must be emerging somehow within it, well, you're in good company. Very few serious thinkers in the field would defend the idea that a philosophical zombie is possible at all. But there is another question that the zombie helps us formulate, perhaps a good scientific one. If philosophical zombies can't be built, where did the consciousness stuff

come from in the copy of you? Was it actually somehow there in the matter in the drawers before we started to build the zombie? Does that imply that everything has a tiny bit of consciousness or a mental property associated with it? Does the right physical configuration somehow unlock it and allow it to flow,

and that gives rise to a unified feeling of consciousness? This notion points to a theory called panpsychism that we'll get to a bit later. Or is consciousness simply a kind of law of nature? Consciousness just emerges given the right flow of information within a system? As strange as it sounds, there is simply a principle of physics which states that a certain kind of information processing just results in the system having an inner experience of being. We may get better at describing the kinds of systems that inevitably result in consciousness in the same way that we can describe systems that unfailingly result in all kinds of systems that inevitably result in consciousness, in the same way that we can describe systems that unfailingly result in all kinds of emergent phenomena, like the kinds of descriptions of the behaviors of atmospheric conditions which inevitably result in hurricanes.

But really, that's the whole story, and the best explanation we will ever, and could ever, get about consciousness. But that last bit of strangeness is deeply unsatisfying to some people. And Sam is amongst those thinkers who contend that this kind of explanation will always be unsatisfactory and be of a fundamentally different nature than other scientific explanations of emergent properties. There is just something about the intuition which the zombie story inflates that protests against these types of correlative and reductionist explanations. The gap between even increasingly detailed descriptions of complex physical processes and something like a rich inner subjective experience of seeing the color red,

or feeling love, or the taste of vanilla, or the awareness of hope, is just too wide and of a nature that it could never be closed. In episode 96, Sam tangled with a thinker who disagrees with this declaration of an unbridgeable gap and is not shy about it. This is Thomas Metzinger, professor and director of the Theoretical Philosophy Group on Neuroethics and Neurophilosophy at Johannes Gutenberg University. Here, Metzinger expresses his frustrations with the idea of a zombie and laments how it can sidetrack what he considers a serious and confident effort

to arrive at a true science of consciousness. You're not a fan anymore, if you ever were, of the framing by David Chalmers of the hard problem of consciousness? No, that's so boring. I mean, that's last century. You know, we all respect Dave, and we know he's very smart and has got a very fast mind. There's no debate about that. But conceivability arguments are just very, very... If you'd like to continue listening to this conversation, you'll need to subscribe at SamHarris.org.

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