 Okay, today we talk about some function of consciousness. Function in biology are notoriously difficult to establish. We know that in evolution of psychology, and you can make many, many stories. So this is just a disclaimer. You can make many stories about what's plausible or what's not plausible, but it's very difficult to test any one of them. Probably, of course, because the system may not have what's not involved just for a simple, for a single function, but very often, like, you know, if you look at evolved, highly evolved products in our industrial age, individual features evolved for various different reasons, very often not just for a single reason, and same thing in evolution. And it's very difficult to really establish functional relationship. You can perturb the system and see that certain functions also deteriorate, but usually they're sort of an entire slew of functions. For example, if you do a molecular biology genetic perturbation experiment, it's usually not just one function that breaks down as many, and very often they don't break down totally. It's not all or none, but the performance takes twice as long, or the error rates go up by 10%. Same thing if you do an experiment in neuroscience where you take out a part of the brain, then very often you get some interference, but the interference will usually not be all or none. It's not the animal will be totally unable to do this task. So first of all, I try to make a list of the different processing modes. I think this might be useful at this point, sort of that the brain can engage in, or that any brains can engage in brains that are in principle able to be conscious. So first of all, there's the processing mode, so you can think of it as a nod to Siegfried Freud. There's the entire huge domain of things that are entirely unconscious. It's probably, if I would have to bet, I would probably say it's 90% plus of the nervous activity in the brain. In other words, if you just count action potential, for example, how many action potentials at any given point in time in the brain, I would say it's 90% plus involved in sub-mental computation. In computation, things, for example, I mentioned there are 50 million neurons in the gut. There are many others. For example, there's the entire immune system, right? Very complicated, highly sophisticated. We have no idea how, we're conscious. We have no idea whatsoever to our immune system, yet it's very complicated. And of course, large fractions of our brain are forever beyond the realm of conscious. And that's to be distinguished from those things that I can be conscious of, but I choose not to tend to right now. I could be conscious of the soles of my feet, and I can feel my shoes, but usually I choose not to. So those are different things. That's one set of processing mode. Then they see online, or sorry, or zombie responses, things that are involved in these specific systems, where you can be conscious of them, but usually only afterwards, and so probably usually that involves a different modality. You can be conscious of your eye movements, of course, but usually they're so fast that probably what you're conscious of is something after the fact, or in pain. People in general believe that you withdraw your hand. If you put it on an oven plate and you merely withdraw it, people believe that's because they actually, they withdraw it because they have pain. I think very often that's not true. I mean, of course, if I'm totally blind, if I'm, that may be true in a certain condition, certainly, you know, remember Lawrence of Arabia in, the character was saying Lawrence of Arabia, you know, when you put his finger in the flame, he says, well, the trick is not to mind it. So there are, of course, exceptional things. In general, what happens first, your body signals, or your body, you know, your sensor sends a signal, the temperature is arising, and then you make this very quick reflex, you withdraw it. In fact, some of it might literally be a reflex that doesn't involve the cortex prop or the brain prop, it just involves spinal cord, but that the pain associated may well take two, three, four, five, six or milliseconds to develop. So you don't actually withdraw it because of that subjective feelings, but that subjective feeling comes afterwards. Then there's sort of pre- and post-NCC activity, so there's all the activity. When there is an NCC, you know, you either see something or feel something, but either they're precursor to that, like in the retina, or because, for example, I trigger motor activity, so I see something and then I initiate motor activity in response to what I see, so I call that post-NCC activities. Clearly, if consciousness is a causal property of an involved system, then there has to be something, it has to affect something, right? Otherwise, it is really truly an epiphenomena, which, of course, many people think it is. So unless it is an epiphenomena, if it's not an epiphenomena, the NCC, the neuronal quality of consciousness, has to causally influence the world in some shape, way or form, and so that you can think of the post-NCC activity. That may or may not be conscious by itself. Then there's sort of unfocused fleeting consciousness, the things that if you drive around, you know, let's say you're driving on a road and you're thinking of something, there are things that sort of stream past you, you may be conscious of those things, but only for very brief time. Okay, we'll talk about Friday when I flash up something. You might, for very brief time, sort of be conscious of most of those things, but then you only attend to one or two, and those other things that you're not attending to, sort of rapidly decay, rapidly decay into oblivion. But you were briefly conscious of them. Then, of course, there is a focused sensory consciousness, the one that we mainly study, because it's the one that sort of, you can maintain it for a very long time, you can manipulate it using all delusions. You can get an animal very nicely. At least you can get the behavior in animals that looks like they have focused sensory percepts, particular visual percepts. So this is the one that experimentally, by far, the easiest to study. Then there's six. Now, this is not necessarily an ascending pyramid here, an ascending scale, so I didn't know where to put dreaming. Dreaming and ascending in terms of conscious is a highly conscious state. It's different from normal awake behaving in a number of respects. So, for instance, you don't recall things. Typically, when you dream, you don't recall things. Of course, you can. If I wake you up when you're dreaming and you're merely talking to tape recorder, you know, if you have a dream diary, you merely write down what you remember. Of course, you can be conscious of things, but unless you do that, it quickly fades away, partly because part of the brain involved in hippocampus is shut down. Also, you have a notable lack of insight. I mean, there will be truly bizarre episodes. You know, you'll meet a long dead relative and then the next second you'll be flying and then, you know, you'll be chasing somebody. But you never have a feeling that this is bizarre. So, in a game, we can see a neural correlate of that, that certain parts of the prefrontal lobes that mediate sort of insight, those are shut down in dreaming. But certainly, it's a highly conscious state by any definition, I would say. And then there's, of course, self-consciousness, insights, et cetera. This is what most people, if you just stop a random person here in downtown Colorado and ask them, you know, what do they think about self-consciousness? They talk about self-consciousness, the fact that I'm me, I know I'm Christoph, I know what I had for breakfast, I know I'm gonna die, I know, you know, I'm a scientist, et cetera. This probably might be restricted to a few species. I mean, you know, I would suspect even in monkeys, it's much less developed. Of course, you probably all know these experiments they take chimps and they paint spots of pain, focus them on the forehead and then they do it either before they expose them to mirror or after they expose them to mirror. And then those chimps that are familiar with their own image, in other words, that have seen their own image in the mirror and then if you paint things on them, you do it when you anesthetize them or when they're asleep, then they realize something is amiss and they sort of, they try to, you know, grab at it and they try to sort of, they see something isn't there. So at least they seem to have a visual self-image. Now, many animals, most animals don't pass that self-recognition test, but that just means that most animals are on that vision, are not that visual. I find it difficult to believe, for example, that dogs, you know, as you know, I've shown you my dogs on pictures before, I love dogs and I think they're quite conscious, but, you know, I find it difficult to believe that they don't have some simple forms of self-consciousness. Certainly they, you know, when you, when, certainly they have some simple forms of, it might well be true that they have effective forms of self-recognition and self-recognition. As you might know, who's had a dog here? So you might know if you go out with your dog or if you have more than one dog at home that your dog will, they won't smell their own poop, right? But they'll spend many seconds or a fraction of a minute smelling the poop of another dog. So at least it tells you they must be able to speak. They must have some simple form of factory distinction, maybe not a visual distinction. Although for the first time, this new dog, a mixed husky and germ shepherd, she looked, you know, I've had many dogs throughout my entire life. The first time a dog, she looked into a mirror and then she, this big bedroom mirror, and then she approached herself, her ears went up and she approached very slowly, she went down, you know, just like dogs go when they see something. She stretched and really went down and then she saw me in the mirror and then she waited and wagged her tail so she was actually beginning to interact. That's very rare. I mean, chimps do that. You can see chimps, you know, they play with their image, they play with their teeth. They really understand what's going on. Most other mammals don't. So it might be possible even other animals have some simple form of self-consciousness, you know, like olfactory, etc. But clearly, I think that's something that's intimately tied up, of course, to language, to semantic processing, etc. Which, you know, some animals might have a simple form, but it's basically, you know, to a first extent, it's probably just us, homo sapiens. And so, of course, that makes it much more difficult to study experimentally. Although I've yet to see any evidence that this is in any way, shape or form, fundamentally different, for example, from this consciousness. You know, I think these are all elaboration upon a common, you know, a common mechanism that evolution came up a long time ago and this just, you know, here you're just applying it to yourself, right? Here you're not applying, here you're applying it to vision or it's being applied to vision or faction. Here it's being applied in a dreaming state and here you're just applying it to yourself and you do that, you know, iteratively a number of times. Now, when it comes to the function of consciousness, there's sort of two camps, or three camps. There's one camp of the mysterious who argue, like Colin McGinn, that if there is a function, we cannot understand it. He uses the argument, I think, of it's cognitive close to us. Here's his analogy, it's a bit like saying, trying to explain to a person who was never sighted, who was born blind, trying to explain to a person like that what it means to see. Which is, we know this from colorblind people, who are truly colorblind, the achromat that we mentioned, that are born without any cones. Because there's one well-known instance of a scientist who's a visual scientist in Oslo, I think, in Norwegian, and he's a visual psychophysicist and he's written an account about this and he says, yes, he can sort of rationalize about color and he knows a lot intellectually about colors and cones and wavelength discrimination, all that stuff, he knows intellectually. He knows how to make certain choices when he comes to his clothing, just based on experience and from the way different claws sort of reflect the light. His sister, one of which is also an achromat, he's got a lot of feedback, but he says, fundamentally, color to me doesn't mean anything. It's something very abstract, I don't know really what that is. And so here the argument is that we cannot imagine the function of consciousness just beyond us, what chance does an ant have in order to have an understanding of relativity. Now, of course, I mean, I don't have a lot of patience with this argument because it's, of course, defeatist by its own, by its very nature, right? And, well, what can I say? Defeatist. Some cultures people were short for defeatism. So then there's epiphenomenalism. Of course, you know, it might be true in the fullness of time that we don't understand it, but I just don't understand how we can right now make a reasonable argument that we can never understand it. Then there's something called epiphenomenalism, right? Epiphenomenal phenomena and then epi. And many people say this and, again, it's difficult right now to rule this out. So the idea says that ultimately, the consciousness by itself doesn't have any function. That it's an epiphenomenal. It's a bit like a shadow, the shadow of a tree. Or the whistle is a very famous quote here. This is from Thomas Henry Huxley, the person sort of the popularizer of Darwin. Some people call him Darwin's bulldog. He's written extensively about science at the end of the 19th century. This is an address he gave very interesting to the British Association for the Advancement of Science where he argued strenuously against the Descartes argument. So for those of you who've ever read René Descartes, which you should because he's sort of the modern founder of the modern study of the mind body. And of course he made, he sort of popularized the dualistic notion that's at the basis of many, many people thinking even today that there's this, you know, there's cogitans and there's ex-tans. So there's physical stuff, we would say. And then there is this mental stuff. And physical stuff is everything in our bodies and everything in the animal bodies that makes us move and do and act. But then in addition there's this mental stuff and he says that's unique to us. And that sort of, you know, he connects it to the pineal gland. And so from that point, well, that just sort of epitomized the distinction between animals and us. And animals don't have any conscious sensation ultimately. They have all the animal fluids, the same ones that we have according to René Descartes, but they don't have this extra mental stuff that gives them consciousness. Now he argues against that, Huxley, meaning for the reason of evolution and continuity, I just said that the behavior is too similar and clearly animals seem to have pain and how can we argue that animals don't have pain when you see a cat or a dog or something in pain? They behave very similar as we would, which is, you know, eminently, which is what we, of course, believe today. But then he comes to, he makes this, he doesn't understand what the function of this could be. The conscience of brutes would appear to be related to the mechanisms of their bodies simply as a collateral product of its working. And to be completely without any power of modifying that working as a steam whistle, which accompanies the work of a locomotive engine, is without influence upon its machinery. Of course, you could make a sophisticated argument here. Of course, a steam whistle has a function, right? The function is namely to warn people to get off the track. So it doesn't have any specific function for the locomotive itself. Just like you could argue, because people say, well, it's an epiphenomenal like the shadow cast by a tree on a plane. Of course, for the tree, it might be an epiphenomenal. But of course, you know, if you have a canopy and you have lots of these trees that throw shade, that provides, you know, it's a real phenomenon. It provides nourishing ground for other organisms to live in the shade of the tree. And some modern philosophers embrace this. And I think it's very difficult to know because some philosophers are very, very slippery, very slippery. So I think Dan Dennard, who's probably one of the most famous modern philosophers, together with Charmas and Churchill and who looks at the question of consciousness, sort of ultimately takes this approach. And ultimately he says, well, there really isn't anything like consciousness. He tells this interestingly, he's very good at anecdotes and analogies, although I think he's too overly fond of them because it's very difficult to pin them down. So he says, well, it's a little bit like when people talk about magic, you know, magic shows and people ask, well, but surely you don't mean real magic. You know, like real magic, like, you know, actually, you know, making things sort of, you know, physical and possible things disappear. And people say, no, no, I don't mean real magic. I mean, like stage magic. So he says, well, there, of course, we know, at least we think we know that real magic, real magic doesn't exist, but sort of stage magic exists and has to be explained. And so he says, well, this is to him, this is the problem with consciousness, that to him there isn't anything special. Of course, we have to explain that people claim they're conscious and people claim they have these first person states that are not accessible to third persons, right? I mean, you know, that ultimately you can never access my brain, that's a claim. I'm not sure that's true, but that's a claim. You cannot access this mental state I have. So it's inaccessible to third person. He says, that clearly has to be explained that people claim that this is, but there really isn't anything else to be explained. That sort of, I had a long correspondence with him and I'm going to meet him again next week at this very point again to try to understand. But I think that's sort of the nature of the argument. And a number of people have, I mean, many, many people have made it, so Dave Chalmers talks about the net blocks most famously. So it's a little bit, I mean, you can think, I think of it probably as a sleight of hand tricks. And the trick goes in the following way. They say, well, let's think about consciousness, all the function of consciousness that people claim it has. Planning, as you'll see in a second, or access to memory, or that you can talk about your states to other people. So it's involved in interspecies communication. And whatever, working memory, you make a whole list of function of consciousness and you put them on one side. You can call that access consciousness or that's the easy problem of consciousness. Namely, all those things were functions. Whenever there's a function, we can then look for a mechanism in search that mediates that function. And that might be practically difficult, but it's not difficult in any conceptual. Conception is easy. But then what remains, so these philosophers claim, and this could be the sleight of hand, or it is a sleight of hand, they say, well, what remains are all the ineffable aspects of consciousness. You know, the feeling of consciousness beyond the mere function. Beyond the function, I say, that pain obviously has a function, the feeling of pain has a function to not make me put my hand on the hard stove or to overextend my... You know, there are some people who were born without pain. Receptors, usually they don't survive very long. They're usually used not to survive very long because they got burned and overextended. It's just not good for you not to have any pain. So, I mean, you remove all those functions, put them on one side, that's the easy problem, or access consciousness, but then there still remains this ineffable thing, this bad thing, this bad aspect of quality, right? It just hurts to have a tooth pain. It's just bad in some deep sense. And so that doesn't have any function because the aspect of bad that makes you want to run away and not eat anything and so maybe protect the teeth from further infection, et cetera, et cetera, that's all function, that's all in access or in the easy problem of consciousness. And so what remains is the hard problem of phenomenal consciousness. These are very similar notions by different philosophers. And that really doesn't have any function, so it is claimed. And it exists. So at least people like... Chalmers is very explicit about this and also net blogs. He says the ineffable part clearly exists. It's not a problem for him. He very deeply believes that the first-person point, in order to have a complete description of the universe, we have to incorporate a first-person account in it. If we want to make a list of all the things in the universe, if we don't include feelings, then he argues we'll have a limited view of the universe. And so to him there's no question that these exist, different for example from Dan Danett. But he says they don't have any function, yet we still have to explain them. And so of course, if they don't have any function, then you have the problem, if you're a biologist, you have to have the problem of how could they have evolved. If they truly don't have any function, how could they have evolved? Because they're clearly very sophisticated. They're not random. They are reproducible. You can have the same... It's highly reproducible. It follows laws. It's highly structured. There are certain relationships that you can draw up, that you can draw up in the color space. It was in they have relationship. They can influence the other color, and sound can influence the other in a highly lawful way. So it's difficult to believe that all of this is an epiphenomena. But it might be true. What is his counter argument? I don't know. I don't think... He doesn't think ultimately it has a function. So from him comes the zombie argument. I introduced the zombie last week. The zombie is a creature like me. He claims he's conscious, but he's not conscious. It doesn't feel like anything to be the zombie. He makes... In his famous book, he argues that you can make a... It's logically consistent with all the laws of the universe that a zombie could exist. He said, I know, in reality, they don't exist. But he says, in principle, they could exist. There's no law in the universe that said they can't exist. Therefore, conscience does not follow from the physical laws of the universe. It's not supervenient. He used this complicated notion of supervenience. It's not a logical supervenient from the laws of the universe. And so it's something extra. You need it to describe the universe, but it doesn't have any function. Now, that might be true in some way. I mean, people now go through this argument for volition. It's an ongoing discussion right now. The question of free will and volition and can an act have no physical precedence? Now, of course, from a scientific point of view, we think that's impossible. For every B, there has to be some A that precedes B, at least in the microscopic world. In the microscopic world, things might be more complicated. And so clearly, many people say, well, we have an illusion of free will and this illusion itself might actually be functional advantageous. People call it the feeling of authorship. The fact that I believe that I'm the author of my action, the fact that I believe that I myself was responsible for lifting my arm sort of makes me, in one sense, a more effective actor on the stage of the world. It makes me do things. It makes me be an optimist. It makes me believe in the doable things that I can do things that I can influence the world because I have this feeling of authorship. Like, Wigner and I think in the new book by Dan Dennett, that sort of thing argument. But ultimately, this feeling is illusionary. So it might be with consciousness. I don't know. I personally, as a biologist, I find it very implausible, but the world tonight is large and full of wonders. We don't know. So that's one tack to the problem, epiphenomenalism. And, of course, it's difficult to really prove this ever. That's a trouble. this. Because, or to disprove it for that matter. So that's why I'm now, it's another reason why I'm not terribly interested in it. Because, you know, every time I say, well, here we've discovered a function, well, that's not really conscious. That's really, that's the easy problem. That's the axis consciousness. So, you know, in that sense, it can never be, it's one of these logical possibilities, you know, almost like, you know, solipsism, that states, you know, the only person out there is me. There isn't really any other subject. The world, there's one subject that means everything else is an object. You know, again, it's, you know, we can all agree this is logically possible, but it's, you know, rather implausible that I should be the only person endowed with this. Oh, yeah, yeah, I mean, the person who would look like me have, so, I mean, he could challenge the epiphenomenalist, but they can sort of still retreat. You can say, well, so I claim that there will not be a person, at least on this planet, who knows, you know, I mean, I'm not saying, I'm not saying that evolution couldn't have come up with organisms that are very complicated that, that, that can do all sorts of things without consciousness. I'm not saying that because I don't know that. All I'm saying that on this planet, evolution took this particular pathway that evolved creature with consciousness, and that if you interfere with any, with any aspects of the functional aspects of consciousness, you will always get a loss in associated subjective feelings. In other words, you're not going to get, for example, a perfect blindsided patient. Remember blindsided? Blindsided, you have a patient who claims that they don't see it. They can still do simple visual motor behaviors. They have still some residual abilities, like they can point at a light source, you know, they can see it moves to the left or it moves to the, to the right, although they claim that they don't have any visual perception. So, now, that's only for very simple stimuli, like for a single stimuli that moves, you know, that doesn't, isn't too dark or that doesn't move too slow. So, so you would have, so I would be much more impressed with this, with this argument if you could show me a patient that has normal vision, basically, but that claims, and that the person claims that, that she's not conscious. Of course, that's, again, not as easy because you have to make sure that the person isn't just a liar, you know, or a philosopher that for some reason, and I'm not joking here, I think some philosophers are just ridiculous when in their total denial that they have, I've had this discussion with some, some, they, they claim that just not conscious. They say, no, I don't know what you mean, I'm not conscious. You know, I, I, I don't know what, I mean, I find it sort of, you know, I mean, how can I argue with this guy? And, yeah, of course, you know, so it's, it's, so again, it's, it's tricky because you can always retreat into that. But, but, and of course, you could be paralyzed, right? Now, there are people, for example, who are not, I don't know, I don't think they're hysterics in a conventional sense, but they're, for example, something known as Anton's blindness, Anton, after the doctor. So in Anton's blindness, you have a patient who, who, who's blind that he denies it. It's difficult to explain, right? So he, he, he, he, he's, you know, if you ask him, well, well, well, you know, you know, just describe the surrounding, you know, he'll make some, you know, he might know that he's in a hospital because he can see in part of the visual field or because he, you know, he hears it, et cetera. And so he'll, he'll make a stab at it. But, you know, after a while, you discover he's just totally confabulating. Now, usually this tends to be a transient thing. I mean, it goes away after a few weeks, but it's, it's there. Anton's blindness, it's a well-known phenomena where people just totally deny that they are blind. So it's a little bit like, you know, neglect, et cetera, where people just don't have access to that visual field, yet they, yet they just don't have the experience that there's nothing there. I mean, very often when, when you're seeing some of these rare patients or read some of these rare patients, you really have the feeling you're hitting an outer limit of human sort of imagination and understanding that because they've lacked some basic structures of the sensory of the, of the apparatus of thought, right? We use our brain, not only to sense, but also, of course, to think with some reason. And if you lose aspect of that, of that apparatus, then of course sort of, you get these really weird things that are really difficult to understand, but, but, you know, they, they seem to be real phenomena since they're reproducible and different patients seem to have, seem to have them. And so here it's still, I find it difficult to understand the world of somebody who has Anton's blindness. But there you have it. And now, so I, you could challenge if you phenomenonist was saying, well, are there any patients have subjective feelings without associated functions? So that's one way, right? You want a double association. So when people say, yes, I can see like, so that's, that's like Anton's blindness, as well as patients that can sort of do super blind side that have all the normal visual abilities, yet claim that they cannot feel. If you have a person like that, then sort of, then I would say yes. If you have a person like that, that release evidence for epiphenomenalism, because clearly you can, one can exist without the other. Now my, now my prediction is leaving aside weird things like Anton's blindness, certainly that, you know, or people who just pathological lie that isn't going to exist. It doesn't exist. And, and people like David Chalmers agree. They say, oh, yeah, I don't have any trouble with this because I know in the real world, in the real world, you know, zombies don't exist. But, but it's possible that they might exist. And to me, that's really like saying, well, you know, we could imagine that there's a world where you have molecular motion, but you don't have heat, right? I mean, you could imagine that. It's just in the real world, you know, molecular motion is identical with heat, right? That's, I mean, physically they're the same. I don't know. It's a bit like saying, well, you know, I could imagine as a world in which they're dragons and they, you know, they love gold, you know, they love to sit on big gold, pops of gold. And, you know, if you kill them and bathe in their blood, then you become, you know, you become, your skin becomes impenetrable. Sure. I mean, yes, I can imagine, logically imagine a world like that. And, you know, many people have in the great myth and Richard Wagner and Siegfried, etc., but it doesn't make it any more real if you want to deal with the real world. So, but there you have it, philosophers. Okay, now, there are many, many people going back a long way through sort of a thought about computational accounts of consciousness. And in fact, I was struck two days ago, I visited, I visited the beast in its lair. I went up to Microsoft, actually, I spent a day at Microsoft, at Microsoft research labs. I showed them my tattoo. And I talked to them about consciousness. And what was ever interesting, so they have this lab of 350 people up there, they do, for the most part, sort of AI, you know, what you would expect, computer science. But they also have people who think actually, who think about some of these issues. And there are sort of some interesting thoughts about reasoning and meta-reasoning in computers and to what extent meta-reasoning is equivalent to something like, like consciousness. Yeah, so it's an ongoing concern that people think about these issues. Now, they range from things like, you know, the different people who said there's a combination of these things like setting overall goals, long-term goals. You know, so this would be what AI people call meta-reasoning, right? So clearly I have to do certain things in order to survive the next minute or two. But then I have long-term goals, you know, like my goal for today or my goal for the week or for the month or for, you know, my professional life or for my overall life. That's why you need consciousness. You need to learn about complex events. You need to associate, you know, like in conditioning, but not just, you know, delay, okay, we'll talk about this Friday. But you need to sort of learn complex events that, you know, I do something and then a minute later this happens. And so these complex chain of events, I need consciousness. I need to flag when there's suddenly, you know, like an error in hardware interrupt and interrupt in a machine architecture. I want to flag those because those are particularly important when something funny happens, when there's a discrepancy because that tells me something is wrong about my view of the world, my model of the world. I need to label the now, people have said that. The current present, I need to distinguish that from the past and the future. I find that weird, but top-down attention. Of course, many people have said that top-down attention, the content of top-down attention is sort of identical to the content of consciousness. You want to access shorter memory. So there's a long literature, working memory, a short-term memory, people like Bernie Bass connect that to consciousness, making decisions, planning, creativity, forming analogies. I'd seen one situation and then saying, well, that situation is similar to another situation. Self-monitoring, I guess that relates to flagging and consistencies. In fact, the state of other animals or people. So consciousness is not so much a function for myself. If I'm a hermit, I wouldn't need consciousness, but it's in order to live in communities of people. So we can live together. So it's useful for me to know your state. So you want to talk to me about it. Language. Many, many people believe this, that the main function of consciousness is to generate language and therefore that only truly humans have consciousness. Then some nice, it's a really nice paper by a cognitive scientist, oh, must be over 20 years ago, that connects. This was at the time when power machines were really hot, the hot ticket, massive power machines. And they were arguing, well, sort of consciousness is a little bit like the OS, the operating system, that you have all these online, these automatic procedures that allow you to deal with the oncoming things. And you have your face recognition software and you have your speech understanding software and you have your operating, your cycle and your clock and you have to service a bus and all of those things. Those are sort of all automatic zombie systems. But then you need some high-level monitoring that sort of allocates resources in a clever way and says, okay, now do this. Particularly if you're under time constraints, if you're under time constraints and you need something that does a rational resource allocation over long terms, or let's say during idle period when the machine is idling, then you want to use the idle resources in order to sort of to gain plan. And all of those functions could be related to consciousness. That's the argument here. Minsky has said something similar in the society of minds. Now, for my money, a lot of these functions could be along the right line. So again, I think it's unlikely that there was just one single function. There are probably multiple functions. And I mean, probably many of these along, at least some of them are probably along the right lines. So we went on records and said this in 1995. So our idea is based on the idea of the biological usefulness of visual awareness. It's strictly, of course, we can only talk about the function of the neuronal correlate of consciousness. And this is to produce the best current interpretation of the visual scene in the visual domain, and in the light of the past experience either of ourselves or of our ancestors. And to make this compact description available for sufficient time to the parts of the brain that contemplate, plant, and execute voluntary motor outputs. So the idea is that you can call it also the executive summary hypothesis. For example, if you read presidential histories like Churchill or like Ronald Reagan, then these people were particularly Ronald Reagan. He was famous for the idea that he said, OK, there's a complex subject, you know, war in, let's say, between Taiwan and mainland China. What's the possibility of war? I want you to summarize all the facts on a page. And I want you to give me on the page the two or three options that we have. And then every complex topic, I want you to reduce it to one page and give me the option of that page. So you have to take all the knowledge you have about a particular scenario and reduce it to something manageable. Now we all know our brains are resource limited. And particularly if we want to deal in real time with things, we need a compact representation of what's currently relevant, what's currently out there. So the idea is that what consciousness gives you, it gives you a compact representation of things that are currently of interest to the organism. And of interest, it's sort of very fuzzy, right? Of interest depends on my goals right now. It depends on my experience. Depending on my visual experience or other experience, I'll find different things of interest. And of course, it's also embedded indirectly in the genes, an animal, a dog here has a different interest than a human has. But the idea is, and it has to be compact, because clearly if I wanted to planning in a reasonable amount of time, I cannot have all the information accessible at the same time. I just couldn't deal with it at the same time. So therefore, the capacity of the content of consciousness is very limited. But that enables me to process things relatively fast. And I make this current summary of everything that's right now important to me. I make this accessible to the planning stages. The stages in the brain that plan things at the time scale of seconds, minutes, hours, up to including lifetime. And that execute voluntary motor outputs, not the automatic one, because that's dealt with all the other systems, not the zombie system, because again, they're highly specialized. But as we argued, they're only acting here now. They're responsible for reaching and grabbing. But now I'm talking for things like, if there's an earthquake suddenly here, I need to know where's the exit, how can I get to the exit? Unless I rehearse it a thousand times, but I haven't done it before, that's where I need to plan voluntary motion, voluntary motor output. So that's to ask a function of consciousness, or at least one of the important function of consciousness, which is not to be similar to what some of the other people have said. However, it has some consequences. People haven't really thought about this. Some direct anatomical consequences. So from this, executive summary hypothesis, the idea that the brain has this mechanism to summarize what's currently of relevance and ship that to the planning center. So the planning centers of the brain are roughly in the prefrontal lobe, everything in front of the central sulcus, more specifically in the prefrontal lobe. That's where we do planning. We know that particular from experiments in patients who have strokes there, or like a famous patient, one famous patient had a piece of iron by an explosion projected through the part of the brain. So some of these patients will have very selective disturbances or pathologies of planning. They make obviously totally wrong lifestyle decisions, totally wrong that are obviously so wrong. And yet they cannot be dissuaded from doing these things. They have obviously lost their ability to plan a different time scales. It's one part of the feature of the frontal lobe syndrome. And so therefore, we surmise, well, if that's a function of consciousness, then of course, if you look for it to correlate, then you have to look for neurons in the visual domain that summarize the visual information. So they're probably reasonable high level neurons that summarize the visual information and then chip it off to the planning centers of the brain. Now, we're not saying that planning itself is conscious. We know, I mean, there's a lot of psychological talk about, a lot of this planning involves, I mean, some of it obviously involves over thinking about it. I can plan my next trip and I can think, what do I need to take and how I'm going to drive, et cetera. But there are also certain things that you find yourself, you find yourself, you're suddenly taking a decision on how you're going to get there or which of two alternatives you're going to pursue. So some of it seems to be unconscious, but it's just in making that information available. That's sort of where the rubber meets the road and where consciousness occurs. So therefore, we predict that there should be neurons in the visual system that talk to the frontal lobe and those are the neurons that are involved in consciousness. Those are the NCC neurons. Now, at the time we instilled today, if you look at the neuron anatomy, if you look at neurons in the primary visual cortex at the back of the head here, there are no direct connections from V1 into the front of the brain. In fact, there's no connection from here to anywhere beyond sort of the central sulcus that limits sort of the sensory part of the brain crudely speaking from the forward part, the motor part of the brain. All the connection V1 sort of they stopped before. And so therefore, we at the time argued that the NCC, the neural colloid of consciousness, is not in V1. Of course, you need V1 for seeing, but the NCC itself isn't in V1. And of course, we spent an entire class talking about the fact that there's lots of evidence, certainly from the monkey electrophysiological literature, that you can have literally millions of neurons that fire in V1, yet all this furious activity is not made conscious in the sense that they're neurons that fire to a stimulus that's perfectly perceptual suppressed. The monkey doesn't see it. You, if you do the same experiment, you don't see it, yet neurons in V1 fire like crazy. So that strongly supports the idea that yes, whatever V1 does, it does not give rise directly to consciousness. Of course, it could be for many reasons, but it's certainly compatible with this hypothesis. So what makes this hypothesis so different from all the other ones is that there is some attempt to come to grips with sort of concrete predictions. Because none of these people, in fact, for the most part, these are psychologists, they are AI people. They don't make any sort of specific prediction that's testable in a neo-biological context. I mean, we're talking already about this. I'm not sure if I need to repeat this, that this contrast was all the other things that we can do without consciousness, particularly all these highly trained sensory motor agents, these zombie agents. We talked about, I think I gave you this quote already. Zen and the Art of Archery, this beautiful quote that really fits the bill perfectly. Did I show this already? I think I did, right? So this one, did I show this from Neomancer? It's also nice. It's not quite as classy. It's one of my favorite science fiction books, so that's why I said it. And yeah, so that we have these wonderful systems that complement consciousness, these zombie agents, they allow us to move gracefully, effortlessly, very quickly, very rapidly, particularly if we train, move through the world, drive through the world, dance through the world, climb through the world, whatever you choose to do. If you do it at an expert level, you do it effortlessly, like walking or biking. The most of us will do that, or swimming, or any of these other, more simply, or playing, if you play a violin. If you can do it so fast, you can do it so effortlessly that clearly you don't have time to think about it. Yet if you train enough, you do it perfectly. You have sort of this Muslim memory. Probably at the time when you acquired this, you needed to be highly conscious of it in order to learn it. But that once you have learned it, you've sort of given it off, handed it off to a different system, a ZOMI system, maybe just a feed-forward system, and that performs it without associated conscious percept. And so you really have the idea that you have these two complementary systems. You have this whole collection of online ZOMI agents that can do simple things, but they can do it effortlessly and fast. They can deal with sensory input and give rise to complex motor output, yet they are relatively stereotypical. The advantages are very fast. And that's complemented by a system that's much slower, because consciousness takes a few hundred milliseconds, or it's not longer, to rise. But it's much, much more flexible. I mean, all the things that humans can do, allow them you can do because of functions associated with consciousness. Of course, this raises the question, well, if these ZOMIs are so good, why do you need this other system? Why do you need consciousness? Now in principle, you may not need it. In other words, as I expressed before, it might well be possible that there are, for example, among the thousands of strains of laboratory mice that are out there in the industry in scientific labs, there might already be some that are ZOMIs. In other words, there might be some alleles that have been knocked out. It's some alleles that where some gene is knocked out, or transcription factor that controls other genes is knocked out, so that you don't have consciousness. Yet in a lab environment where it's not survival of the fittest anymore, these mice may perfectly well survive. The claim is in the real world, you couldn't survive because the brain would be far too big. And again, it's an evolutionary argument for whatever it's worth. That if you wanted to have all the ZOMIs, if my entire brain would be ZOMI system to deal with all personal scenarios, all possible inputs and outputs combination, I would need a brain far, far bigger than my own. And so it was cheaper from an evolutionary point of view to have these two systems complement each other. A specialized, rapid system, a whole set of specialized, sort of specialist, if you want, a whole set of fast specialists supplemented by a more general consciousness system. So again, this might be possible that on a different planet and different environments, you have creatures that are maybe not conscious at all. And it might be possible that even out here on this planet, in fact, many creatures might not be conscious, but might be the evolution of their successful. I mean, if you look at something like C elegans, roundworm, three or two neurons, we have no idea whether the roundworm is conscious. We think probably not, but we don't really know. A fly, a fruit fly with 30,000 neurons, a muscatomastika with 300,000 neurons, they're fairly complicated. And they have some non-stereotypical behavior. And right now, we just don't know whether they're conscious because we don't know how to test that. It's just a thought. Right now, we just don't know. I mean, most people assume, of course, they're not conscious. Mystics, of course, assume that they're conscious, but we just don't know. Yes, and with that, I leave you.