WEBVTT - How does consciousness emerge? 0:00:05.920 --> 0:00:09.000 On the podcast, we love to ask deep questions and 0:00:09.039 --> 0:00:12.280 then explore the edge of our knowledge. Today we're going 0:00:12.360 --> 0:00:14.600 to go a little bit meta and try to understand 0:00:14.680 --> 0:00:18.440 the workings of our own minds, the us that is 0:00:18.520 --> 0:00:22.200 asking those questions and yearning to understand the universe, from 0:00:22.200 --> 0:00:25.360 biology to physics, and yes, sometimes even a little bit 0:00:25.400 --> 0:00:29.680 of chemistry. Science gives us this incredible tool to consistently 0:00:29.720 --> 0:00:33.320 build knowledge about the universe, but it's not clear that 0:00:33.440 --> 0:00:36.880 it can tell us about ourselves. That it can help 0:00:36.960 --> 0:00:41.360 us understand why we have a first person subjective experience 0:00:41.400 --> 0:00:44.640 in the first place, why we have an experience at all, 0:00:45.080 --> 0:00:48.440 why chocolate has a taste and pain has a negative valance, 0:00:48.760 --> 0:00:52.319 Why there's something it's like to be me. How's that 0:00:52.360 --> 0:00:54.880 different from what it's like to be a bat? Is 0:00:54.920 --> 0:00:57.680 it like anything to be a rock or a puddle 0:00:57.800 --> 0:01:00.800 or a star? Science, like all you and endeavors, is 0:01:00.840 --> 0:01:03.760 limited by the senses that we use to interact with 0:01:03.800 --> 0:01:07.000 the universe. It can help us understand what we sense 0:01:07.080 --> 0:01:10.119 and find patterns and build models, but it can't ever 0:01:10.200 --> 0:01:13.399 really tell us about the hard reality of the physical 0:01:13.520 --> 0:01:17.480 universe that exists out there beyond our minds and our senses, 0:01:18.000 --> 0:01:20.800 and that same limitation might apply to the other end 0:01:20.840 --> 0:01:24.520 of that sensory pipe. Can a scientist use science to 0:01:24.600 --> 0:01:28.319 probe the nature of the mind while trapped inside their 0:01:28.360 --> 0:01:31.800 own mind? That might just be the province of philosophy. 0:01:32.120 --> 0:01:35.160 Today on the podcast, we're getting philosophical and asking what 0:01:35.319 --> 0:01:39.720 we know and how we can know about how consciousness emerges. 0:01:40.480 --> 0:01:44.800 Welcome to Daniel and Kelly's Extraordinarily self Conscious Universe. 0:01:58.680 --> 0:02:01.840 Hello, I'm Kelly Winnersmith. I study parasites and space, and 0:02:01.840 --> 0:02:04.040 today I'm wondering if we live in a simulation. 0:02:05.320 --> 0:02:09.239 Hi, I'm Daniel. I'm a particle physicist, and I don't 0:02:09.280 --> 0:02:11.400 care if we live in a simulation. I want to 0:02:11.400 --> 0:02:12.760 eat simulated dark chocolate. 0:02:13.000 --> 0:02:15.079 So that's my question. Is it possible that we live 0:02:15.080 --> 0:02:17.880 in a simulation? We're getting philosophical today, let's go all 0:02:17.880 --> 0:02:18.160 the way. 0:02:18.440 --> 0:02:22.640 Yeah, absolutely, it's possible. But it also seems like a 0:02:22.840 --> 0:02:27.800 modern reflection on recent concepts about how computers work. You know, 0:02:27.800 --> 0:02:30.800 one hundred years ago, people thought the whole universe was 0:02:30.880 --> 0:02:33.840 like pipes and cogs, and these days we think it's 0:02:33.880 --> 0:02:37.760 all computers. So it's possible, but we also have zero 0:02:37.880 --> 0:02:41.240 evidence that it's a simulation, and dark chocolate tastes really 0:02:41.440 --> 0:02:42.880 really good anyway. 0:02:42.840 --> 0:02:46.519 That's true, and so does pad see You. I'm hungry today. 0:02:47.680 --> 0:02:50.040 This is why we shouldn't report the podcast just before lunch. 0:02:50.120 --> 0:02:52.440 That's right. I'm so glad that I have simulated taste 0:02:52.440 --> 0:02:54.880 buds and smell receptors so that I can enjoy all 0:02:54.960 --> 0:02:56.200 of those things very much. 0:02:56.280 --> 0:02:59.960 But it is fascinating to think about where your consciousness were, 0:03:00.000 --> 0:03:03.000 where your experience comes from, why it is that you 0:03:03.200 --> 0:03:06.280 even have one while you can like or hate pad 0:03:06.360 --> 0:03:09.360 see You, whether or not that's something that comes from 0:03:09.400 --> 0:03:11.680 the meat in your mind, or whether it's just the 0:03:11.720 --> 0:03:15.600 information circling through those neurons which could be uploaded to 0:03:15.760 --> 0:03:16.280 the cloud. 0:03:16.639 --> 0:03:18.120 Yeah. I mean, I think you'd have to be a 0:03:18.120 --> 0:03:20.840 machine to not like TI food in general personally, but 0:03:20.919 --> 0:03:22.600 I could be wrong. But I'm excited that so you 0:03:22.639 --> 0:03:26.240 and I. We get a lot of emails from listeners. 0:03:26.680 --> 0:03:29.679 You can send those emails to questions at Daniel and 0:03:29.720 --> 0:03:32.200 Kelly dot org. And lately we've been getting a lot 0:03:32.200 --> 0:03:35.160 of questions from folks who have been asking about consciousness. 0:03:35.200 --> 0:03:37.000 I think we've been getting like one a week for 0:03:37.040 --> 0:03:40.120 a while, and we decided it was time to jump 0:03:40.120 --> 0:03:42.960 into the consciousness question, and you lucked out, and you 0:03:43.040 --> 0:03:45.080 happen to know the perfect guest I do. 0:03:45.120 --> 0:03:47.400 There's lots of really smart folks here at you See Irvine, 0:03:47.920 --> 0:03:50.240 and I'm good at googling and finding them and persuading 0:03:50.240 --> 0:03:52.640 them to come and talk to me on the podcast. 0:03:53.040 --> 0:03:54.200 I have a lot of fun, and this is a 0:03:54.360 --> 0:03:57.000 topic that's really close to my heart. I've been thinking 0:03:57.040 --> 0:03:59.480 about it for a long time and also thinking about 0:03:59.560 --> 0:04:03.520 whether it's something you really can ask scientifically. You know, 0:04:03.760 --> 0:04:06.040 science is wonderful and powerful, and of course we are 0:04:06.080 --> 0:04:08.800 advocates for science here on the podcast, But just because 0:04:08.800 --> 0:04:10.920 it's a tool that does let us build knowledge about 0:04:10.920 --> 0:04:13.160 the universe doesn't mean it's a tool that can answer 0:04:13.240 --> 0:04:16.520 every question. Right. You can't answer the question like should 0:04:16.560 --> 0:04:18.280 I get out of bed in the morning? Why do 0:04:18.360 --> 0:04:23.040 people eat white chocolate? Anyway? Right, Not every question is scientific, 0:04:23.640 --> 0:04:25.839 and so there are things about the universe that we 0:04:25.920 --> 0:04:28.080 can probe with science, and there are limits to what 0:04:28.120 --> 0:04:31.240 science can answer. And I've always wondered how much we 0:04:31.360 --> 0:04:35.880 can understand about consciousness itself using science. So I was 0:04:35.880 --> 0:04:38.880 really excited to talk to a cognitive scientist who thinks 0:04:38.920 --> 0:04:41.240 about this all day in a very serious way. 0:04:41.520 --> 0:04:43.640 Yeah, I'm excited that consciousness is sort of at the 0:04:43.800 --> 0:04:47.440 interface of science and philosophy, which makes it a really 0:04:47.440 --> 0:04:49.760 fun topic to think about. And so I had a 0:04:49.800 --> 0:04:51.960 lot of fun today with Megan Peter's chatting with her 0:04:51.960 --> 0:04:52.240 about this. 0:04:52.320 --> 0:04:55.600 Stopping before we dive into this wonderful conversation, we were 0:04:55.640 --> 0:04:59.479 curious what folks out there thought about their own consciousness, 0:05:00.000 --> 0:05:03.560 what ideas people have for why they even have an experience, 0:05:04.040 --> 0:05:07.200 how these few pounds of goo in your brain somehow 0:05:07.320 --> 0:05:10.960 generate all of this joy and frustration that we experience. 0:05:11.440 --> 0:05:14.760 So I asked our cadre of volunteers to chime in 0:05:14.800 --> 0:05:19.560 on the question how does consciousness emerge? If you'd like 0:05:19.600 --> 0:05:21.680 to provide answers for a future episodes, please don't be 0:05:21.680 --> 0:05:24.800 shy to right to questions at danieland Kelly dot org. 0:05:25.200 --> 0:05:26.880 So think about it for a minute. How do you 0:05:26.920 --> 0:05:31.400 think consciousness emerges? Here's what our listeners had to say. 0:05:31.920 --> 0:05:34.680 I think we have to really think about what consciousness 0:05:34.760 --> 0:05:39.560 might mean before we can figure out where it comes from. 0:05:39.880 --> 0:05:41.360 But if I had to make a guess, I'd say 0:05:41.360 --> 0:05:46.040 consciousness is just energy sliding into different forms as it 0:05:46.120 --> 0:05:48.159 rolls along from our brain. 0:05:48.279 --> 0:05:52.400 Jews exponential, exponential extension of the emergence of life. I 0:05:52.400 --> 0:05:55.880 don't think anyone knows human consciousness is an intersection of 0:05:55.920 --> 0:05:59.880 the more mechanistic functions of the human brain and the 0:06:00.240 --> 0:06:04.440 created soul. I think consciousness needs you to have both 0:06:04.520 --> 0:06:08.599 theory of mind and the complexity to apply it to yourself. 0:06:08.680 --> 0:06:11.560 Very slowly on a Saturday morning after a night out 0:06:11.560 --> 0:06:13.599 down the town with several coffees. 0:06:14.120 --> 0:06:18.560 Consciousness is fundamental and that we are as humans somehow 0:06:18.920 --> 0:06:23.480 tapped into it. Wow, consciousness, that's a bigie. Well, I 0:06:23.480 --> 0:06:25.360 think it's magic. 0:06:25.839 --> 0:06:28.920 As the parent of twins who think I'm pretty much useless, 0:06:29.560 --> 0:06:32.720 I'll say it that somehow it involves interaction with others. 0:06:32.880 --> 0:06:36.680 Consciousness emerges when the penguin models in. I've always leaned 0:06:36.680 --> 0:06:40.080 towards the idea that consciousness is an illusion. 0:06:40.440 --> 0:06:42.880 I believe consciousness emerges when the brain's elegical florid of 0:06:42.960 --> 0:06:45.200 plasma interacts with the noise and dangers in the brain. 0:06:45.240 --> 0:06:48.200 Thanks the brain itself is a sensory organ that can 0:06:48.240 --> 0:06:49.760 sense its own processing. 0:06:50.200 --> 0:06:53.200 A pint of strong fresh coffee is a necessary but 0:06:53.440 --> 0:06:54.720 not sufficient condition. 0:06:55.000 --> 0:06:58.200 It's a very complicated dance in the brain. It's a 0:06:58.320 --> 0:07:02.640 very slow process. I think consciousness takes many, many forms, 0:07:03.120 --> 0:07:06.840 things that the brain is doing, neural inspiring, reaching out 0:07:06.960 --> 0:07:12.400 a critical consistency, and an introduction number. 0:07:12.640 --> 0:07:15.200 I don't think we can know how consciousness emerges until 0:07:15.240 --> 0:07:18.680 we know what consciousness is and if we have it all. 0:07:18.680 --> 0:07:23.800 Right, We've got coffee, penguins, magic, all kinds of amazing 0:07:23.840 --> 0:07:26.600 things in there, and a large diversity of answers. 0:07:26.720 --> 0:07:30.360 Mmmmm, And there's a thread here. I've noticed a lot 0:07:30.360 --> 0:07:34.360 of people suggesting that somehow it arises from the complexity 0:07:34.360 --> 0:07:38.320 of the brain neurons, reaching a critical number or you know, 0:07:38.360 --> 0:07:41.200 all these interactions. To me, that sort of frames the 0:07:41.280 --> 0:07:44.680 question but doesn't really answer it, right, Like, why is 0:07:44.680 --> 0:07:48.480 it the complex network of cells can have a consciousness 0:07:48.480 --> 0:07:51.400 emerge regardless of the complexity, Right, It's not obvious to 0:07:51.440 --> 0:07:54.640 me that complexity is enough. And that's really I think 0:07:54.640 --> 0:07:56.960 the focus of the question for today's episode. 0:07:57.240 --> 0:08:00.160 I would personally love to know the evolutionary reason why 0:08:00.200 --> 0:08:02.840 we have consciousness, how does it benefit us? And would 0:08:02.880 --> 0:08:05.800 we expect to see other animals to have it as well? Yeah, 0:08:05.800 --> 0:08:07.680 and anyway, there were so many exciting things we talked 0:08:07.680 --> 0:08:08.559 about with Megan today. 0:08:08.800 --> 0:08:11.360 Yeah, there's lots of really fun questions there, like where 0:08:11.240 --> 0:08:14.000 are there other species of humans which actually were more 0:08:14.040 --> 0:08:18.640 intelligent but didn't survive because our ancestors were more warlike 0:08:18.800 --> 0:08:22.480 or more cannibalistic? Right? Or if you ran the Earth 0:08:22.520 --> 0:08:25.400 experiment a thousand times, how often would you even get 0:08:25.400 --> 0:08:28.720 intelligence or more or less intelligence? All right? Is this 0:08:28.760 --> 0:08:31.400 a fluke or is it a common outcome? Man? I'd 0:08:31.440 --> 0:08:32.920 love to know the answer to those questions. 0:08:33.040 --> 0:08:35.120 And you're also getting into some of the complexity there 0:08:35.160 --> 0:08:38.319 because you were calling it intelligence and where does intelligence 0:08:38.480 --> 0:08:41.360 end in consciousness begin? And what is the difference in 0:08:41.400 --> 0:08:44.319 those things? And it gets complicated pretty fast. 0:08:44.440 --> 0:08:46.640 It does. And fortunately we have an expert to help 0:08:46.720 --> 0:08:49.600 us dig through this. So let's jump right into our 0:08:49.600 --> 0:08:52.840 conversation with Professor Megan Peters from the Cognitive Science department 0:08:52.880 --> 0:08:58.440 here at UC Irvine. All right, so it's my pleasure 0:08:58.480 --> 0:09:01.720 to have on the podcast Professor Megan Peters. She's an 0:09:01.720 --> 0:09:04.240 associate professor here at you see Irvine in the Department 0:09:04.280 --> 0:09:07.920 of Cognitive Science. She's a PhD from UCLA in cognitive 0:09:07.960 --> 0:09:11.040 science and her research aims to reveal how the brain 0:09:11.160 --> 0:09:16.480 represents and uses uncertainty. She uses neuroimaging, computational modeling, machine learning, 0:09:16.520 --> 0:09:19.880 and neural stimulation techniques to study all of this, and 0:09:20.000 --> 0:09:22.400 most importantly, she agreed to come on the podcast and 0:09:22.440 --> 0:09:25.880 talk to us about what is consciousness and answer all 0:09:25.880 --> 0:09:28.920 of our questions and fend off Kelly's poop references. 0:09:29.160 --> 0:09:34.839 Ah, good luck, Thank you both for having me. It's 0:09:34.880 --> 0:09:38.120 really a pleasure to be here. As an aside, my 0:09:38.280 --> 0:09:41.679 PhD is in psychology with a focus on cognitive and 0:09:41.679 --> 0:09:44.200 computational neuroscience. If that matters, So you can cut this 0:09:44.240 --> 0:09:46.120 part out if you want to redo that intro. 0:09:46.640 --> 0:09:48.960 No, we'll find out if that matters, we'll see Yes, 0:09:49.080 --> 0:09:52.480 absolutely great, So let's dig right in. I want to 0:09:52.640 --> 0:09:55.040 know And this is maybe the hardest question we're going 0:09:55.120 --> 0:09:58.679 to ask you all day. How do we define consciousness? 0:09:58.720 --> 0:09:59.920 We're going to be talking about it, We're going to 0:09:59.960 --> 0:10:02.880 be arguing about We're going to be saying do rocks habit? 0:10:03.000 --> 0:10:05.240 Do dogs have it? But it's kind of slippery if 0:10:05.240 --> 0:10:07.320 we don't even know what it is we're talking about. 0:10:07.440 --> 0:10:11.080 So what is consciousness? How do we define this thing 0:10:11.240 --> 0:10:13.560 that we all sort of know intuitively but have a 0:10:13.600 --> 0:10:15.520 hard time describing. 0:10:15.360 --> 0:10:18.640 Super important question and leads me into one of the 0:10:18.640 --> 0:10:21.200 first kind of technical things that we'll talk about today, 0:10:21.440 --> 0:10:24.920 which is the distinction between are the lights on? But 0:10:25.040 --> 0:10:29.200 is anyone home? Essentially, So we talk in the fields 0:10:29.280 --> 0:10:32.360 of psychology and in the philosophy of mind about the 0:10:32.400 --> 0:10:38.040 distinction between what's called access consciousness and phenomenal consciousness. So 0:10:38.080 --> 0:10:40.720 these are terms that the philosopher and ned Block introduced 0:10:40.760 --> 0:10:44.439 a while back, and the idea is that access consciousness 0:10:44.480 --> 0:10:48.520 is about something like the global availability of information in 0:10:48.600 --> 0:10:53.559 a complex system to allow that system to behave usefully 0:10:53.600 --> 0:10:57.720 in its environment, to survive, to seek goals, to seek rewards, 0:10:57.760 --> 0:11:00.880 to get food, to not be eaten by something. And 0:11:01.520 --> 0:11:04.680 the distinction then is between you know, access consciousness, which 0:11:04.720 --> 0:11:07.600 is information goes all over in the brain or in 0:11:07.640 --> 0:11:10.640 the mind if there isn't a brain present. But the 0:11:10.679 --> 0:11:14.319 difference then between that and phenomenal consciousness is that the 0:11:14.400 --> 0:11:19.000 phenomenal consciousness has to do with the phenomenology of the 0:11:19.200 --> 0:11:22.040 experience that the observer is having. So I'm going to 0:11:22.080 --> 0:11:24.679 break that down that really just comes down to this 0:11:25.200 --> 0:11:29.000 something that it is like to be you the qualitative 0:11:29.080 --> 0:11:32.000 experiences that you have of the world. The fact that 0:11:32.080 --> 0:11:36.000 pain hurts. It isn't just a signal like your tesla 0:11:36.000 --> 0:11:38.480 would send to itself, like damage in my right front 0:11:38.520 --> 0:11:41.680 tire or something like that. It's more like it has 0:11:41.800 --> 0:11:44.960 qualitative character to it. There's something that it's like to 0:11:45.000 --> 0:11:46.840 be in pain. If I whack you in the leg, 0:11:47.440 --> 0:11:51.000 it's not just a signal that I've damaged the tissue 0:11:51.040 --> 0:11:52.800 in your leg. There's more to it than that. 0:11:53.200 --> 0:11:56.360 So are you saying that a tesla has access consciousness 0:11:56.400 --> 0:11:59.400 because it notices damage in its tire, but it doesn't 0:11:59.400 --> 0:12:03.160 feel pain, doesn't have anomenological consciousness, or if I miss. 0:12:02.480 --> 0:12:05.200 Ansers, I wouldn't even go that far to say that 0:12:05.240 --> 0:12:08.080 a tesla has any sort of access consciousness whatsoever. I 0:12:08.080 --> 0:12:10.480 think that that's a higher bar there, But I think 0:12:10.520 --> 0:12:11.640 that the distinction is important. 0:12:11.720 --> 0:12:11.800 Right. 0:12:11.880 --> 0:12:14.360 We can imagine a system that has all of the 0:12:14.400 --> 0:12:17.720 hallmarks of access consciousness, like a fancy future tesla. Okay, 0:12:17.920 --> 0:12:20.960 you know that has all of this global availability of information. 0:12:21.080 --> 0:12:25.199 It enables flexible adaptive behavior. It can change based on 0:12:25.280 --> 0:12:28.120 its context. It's not just going according to its programming. 0:12:28.280 --> 0:12:30.440 You know that kind of thing. And yet there's nothing 0:12:30.440 --> 0:12:33.000 that it's like to be that fancy future tesla. It's 0:12:33.160 --> 0:12:37.400 just a zombie. It's just engaging in behaviors that are 0:12:37.600 --> 0:12:40.960 useful for that organism, but there's no one home. So 0:12:42.000 --> 0:12:45.400 someone being home aspect is also really important because we 0:12:45.440 --> 0:12:48.720 can imagine in like, you know, not a future robot scenario, 0:12:48.920 --> 0:12:51.960 but just a medical situation where you've got a person 0:12:52.000 --> 0:12:55.439 who's in a coma or they're in a persistent vegetative state, 0:12:56.000 --> 0:13:00.520 and they might wake up seemingly and have of sleep 0:13:00.559 --> 0:13:04.360 wake cycles and maybe respond to external stimuli. But the 0:13:04.360 --> 0:13:07.840 critical factor in deciding whether you know someone's home whether 0:13:07.920 --> 0:13:11.360 to keep them on life support is whether there's anything 0:13:11.480 --> 0:13:15.080 is like to be them inside. And the flip side 0:13:15.120 --> 0:13:17.760 is also really important in the context of medical science, 0:13:17.880 --> 0:13:21.480 because even if they don't exhibit any of the outward 0:13:21.760 --> 0:13:26.000 signs or symptoms of being conscious, of having access to 0:13:26.080 --> 0:13:29.520 that available information, of being able to behave in their environments, 0:13:29.840 --> 0:13:32.679 someone still might be in there. They might be locked in. 0:13:33.280 --> 0:13:36.520 And so it's this presence of phenomenal experience of someone 0:13:36.600 --> 0:13:40.440 being home, so to speak, that I think is the 0:13:40.559 --> 0:13:43.440 important thing to remember when we're talking about consciousness in 0:13:43.480 --> 0:13:46.800 the context of biological systems or artificial ones. 0:13:47.120 --> 0:13:49.160 So I'm still trying to wrap my head around the 0:13:49.160 --> 0:13:52.040 two different kinds of consciousness. Is there a kind of 0:13:52.160 --> 0:13:54.559 organism or a situation a person can be in where 0:13:54.559 --> 0:13:56.680 they would have one but not the other to help 0:13:56.679 --> 0:13:58.480 me sort of differentiate. 0:13:58.000 --> 0:14:01.320 Well, For humans, the idea is that, presuming that you 0:14:01.360 --> 0:14:05.240 don't subscribe to, you know, philosophical zombiesm that like, you 0:14:05.280 --> 0:14:07.680 have no idea that I'm conscious, right, I exhibit all 0:14:07.720 --> 0:14:10.360 the hallmarks, but you have no idea. But presuming that 0:14:10.440 --> 0:14:12.760 you don't want to go down that rabbit hole, I. 0:14:12.679 --> 0:14:15.480 Do actually in a minute. 0:14:15.600 --> 0:14:18.640 In humans, it seems like they go hand in hand, right, 0:14:18.679 --> 0:14:21.760 that if you have access consciousness, you have phenomenal consciousness 0:14:21.880 --> 0:14:25.080 in general as an awake, behaving organism. But there might 0:14:25.120 --> 0:14:30.600 be cases in specific scientific experiments where you can reveal 0:14:31.360 --> 0:14:35.560 symptoms or cases or evidence of access consciousness in the 0:14:35.600 --> 0:14:40.080 absence of phenomenal consciousness. So there's some very specific psychological 0:14:40.120 --> 0:14:45.040 experiments that suggests that these are separable entities. One classic 0:14:45.120 --> 0:14:49.120 example is a task that was actually attributed to and 0:14:49.280 --> 0:14:52.600 was developed by a cognitive scientist here in my department, 0:14:52.640 --> 0:14:55.920 George Spurling. So this is the classic spurling task where 0:14:55.920 --> 0:14:58.720 you show someone an array of letters. There's like five 0:14:58.800 --> 0:15:01.320 letters in a row, and there's rows of letters, and 0:15:01.360 --> 0:15:04.880 you flash it very fast, and you ask people to 0:15:05.000 --> 0:15:08.520 kind of give their impression of the overall array, like 0:15:08.560 --> 0:15:10.160 did you see it? Did you feel like you got 0:15:10.160 --> 0:15:11.920 the whole thing? And people say, yeah, I feel like 0:15:11.960 --> 0:15:14.160 I got the whole array. That's fine. But then when 0:15:14.160 --> 0:15:16.520 you ask them to report the whole array they can't, 0:15:17.080 --> 0:15:19.120 But when you ask them to report a specific row 0:15:19.200 --> 0:15:22.560 they can't. It feels like there's a distinction then between 0:15:22.560 --> 0:15:26.880 this feeling that you've got phenomenal experience of the whole array, 0:15:27.000 --> 0:15:29.440 but your access might be limited, and so ned Block 0:15:29.480 --> 0:15:33.840 has famously called this phenomenal consciousness overflowing access. 0:15:34.080 --> 0:15:36.240 It seems to me sort of the crucial distinction, right, 0:15:36.240 --> 0:15:40.320 because access consciousness is something we can understand sort of 0:15:40.560 --> 0:15:42.960 on a fundamental level, Like we can trace signals into 0:15:42.960 --> 0:15:45.440 your eye and watch those proteins fold and then up 0:15:45.480 --> 0:15:48.720 the optic nerve and into your brain, but we can't 0:15:49.240 --> 0:15:53.760 know whether anybody's there like experiencing, or what that experience 0:15:53.800 --> 0:15:56.440 of seeing a red photon is, or whether my red 0:15:56.480 --> 0:15:57.960 is the same as your red and all this sort 0:15:58.000 --> 0:16:01.440 of dorm room philosophy kind of stuff, and so access 0:16:01.440 --> 0:16:07.440 consciousness is sort of more accessible scientifically than phenomenological consciousness, 0:16:07.480 --> 0:16:09.240 which is more philosophical. Is that fair? 0:16:09.440 --> 0:16:12.480 I think that's a relatively fair characterization, and that there 0:16:12.480 --> 0:16:15.520 are a lot of kind of current scientific theories of 0:16:15.560 --> 0:16:19.000 consciousness that report to be a theory of consciousness, and 0:16:19.080 --> 0:16:21.360 most of them, really, when it comes down to brass tacks, 0:16:21.440 --> 0:16:24.920 end up being about access consciousness because the phenomenal part 0:16:25.080 --> 0:16:28.040 is really hard to get at. As you said, I 0:16:28.040 --> 0:16:31.400 think that there are some approaches that might be promising 0:16:31.480 --> 0:16:35.120 in this vein. So you could look for neural correlates 0:16:35.360 --> 0:16:40.080 or patterns of neural activity that are associated with reports 0:16:40.280 --> 0:16:44.360 of phenomenal experience. So like I can create conditions where 0:16:44.400 --> 0:16:46.200 I show you the same stimulus over and over and 0:16:46.240 --> 0:16:48.880 over again, and so the early parts of your visual 0:16:48.920 --> 0:16:52.400 brain are responding kind of similarly. I mean, there's noise, 0:16:52.480 --> 0:16:55.480 and there's variability and so on, But if I flash 0:16:55.600 --> 0:16:57.920 the same thing at you over and over and over again, 0:16:58.240 --> 0:17:00.720 I'm going to get a consistent kind of pattern of 0:17:00.760 --> 0:17:03.280 responding in the back of your head, which is the 0:17:03.320 --> 0:17:07.720 early visual cortex. But you might have fluctuations in your 0:17:07.800 --> 0:17:12.119 subjective experience of that stimulus. Sometimes you feel like you 0:17:12.160 --> 0:17:15.239 see it, sometimes you feel like you can't. So to 0:17:15.320 --> 0:17:17.760 the extent that I can hold most of the stuff 0:17:17.800 --> 0:17:19.720 in the back of your head constant, and I can 0:17:19.800 --> 0:17:22.880 measure that in relation to flashing something at you over 0:17:22.960 --> 0:17:25.400 and over and over again. But then I look for 0:17:25.960 --> 0:17:30.320 how your subjective experience fluctuates from one moment to the next. 0:17:30.359 --> 0:17:32.640 I feel like I saw that strongly. I feel very 0:17:32.680 --> 0:17:35.399 confident that I got that right. I feel like that 0:17:35.600 --> 0:17:39.280 was nothing at all. I didn't really experience anything. Then 0:17:39.320 --> 0:17:42.120 I can go look for neural correlates that are co 0:17:42.240 --> 0:17:46.960 varying with the subjective experience that you're reporting to me. 0:17:47.560 --> 0:17:49.399 There are a lot of problems with that too, that 0:17:49.520 --> 0:17:52.080 maybe you don't have perfect access to your own subjective 0:17:52.119 --> 0:17:55.000 experiences and your reports are spurious and blah blah blah. 0:17:55.000 --> 0:17:57.360 But I think that there are ways that we can 0:17:57.400 --> 0:18:00.760 go about trying to get at how the brain constructs 0:18:00.840 --> 0:18:07.000 or supports or represents these subjective experiences that are different 0:18:07.040 --> 0:18:11.960 from just how your brain processes information about the external environment. 0:18:11.760 --> 0:18:14.160 Right, And I do want to get into those experiments. 0:18:14.200 --> 0:18:16.159 But first I just want to make sure we're totally 0:18:16.160 --> 0:18:19.679 clear on these definitions. And I think the example that 0:18:19.720 --> 0:18:21.760 you were a little dismissive of a minute ago is 0:18:21.800 --> 0:18:24.560 actually helpful, at least to me to clarify what we're 0:18:24.560 --> 0:18:27.360 talking about. And that's the example of philosophical zombies. Right. 0:18:27.680 --> 0:18:30.960 The idea here is, could you take Daniel and replace 0:18:31.040 --> 0:18:35.680 him with some machine, biological or whatever that replicates all 0:18:35.720 --> 0:18:39.400 of my actions? Seems the way I do to be conscious. 0:18:39.520 --> 0:18:43.680 But there's nobody home, right, there's nobody experiencing the red 0:18:43.800 --> 0:18:46.080 and eating the pizza and whatever. It's just, but it 0:18:46.119 --> 0:18:50.240 seems like it reacts exactly the same way. So philosophical zombies, 0:18:50.280 --> 0:18:51.960 as I understand them, and tell me if I'm wrong, 0:18:52.280 --> 0:18:56.000 conjectures that it's possible to build something like this, which 0:18:56.080 --> 0:19:00.239 means therefore that the phenomenological consciousness is totally unmeasurable. Right, 0:19:00.280 --> 0:19:02.040 that there's no way for us to know we have, 0:19:02.200 --> 0:19:03.920 As you said, we have to sort of trust your 0:19:04.000 --> 0:19:07.879 first person reports about your subjective experience, which makes it 0:19:07.880 --> 0:19:11.560 difficult to do any actual science. Right, is that a 0:19:11.600 --> 0:19:13.800 fair characterization of philosophical zombies? 0:19:13.840 --> 0:19:16.000 If I missed something, Oh, I have like five things 0:19:16.000 --> 0:19:17.439 I want to say, let's make sure I get to 0:19:17.440 --> 0:19:21.040 all of them. Okay, So first, the idea of philosophical 0:19:21.119 --> 0:19:24.840 zombies has been hotly debated in the philosophical literature for 0:19:24.880 --> 0:19:27.159 a very long time, and there are a number of 0:19:27.160 --> 0:19:31.000 philosophers who say, yes, this is absolutely totally reasonable to 0:19:31.080 --> 0:19:32.719 pause it, that this could happen, And then there are 0:19:32.720 --> 0:19:35.320 other people who say, no, like, that's not really like 0:19:35.400 --> 0:19:39.680 a reasonable assumption. So you know, go read Dan Dennitt 0:19:39.680 --> 0:19:41.880 if you want to hear about all of this stuff. 0:19:42.359 --> 0:19:46.880 But I think that you've touched upon another important point too, 0:19:47.760 --> 0:19:51.320 which is this idea of testing for whether someone is 0:19:51.359 --> 0:19:54.360 in there or not, and how we don't currently have 0:19:54.520 --> 0:19:57.280 the capacity to do that even in other beings that 0:19:57.320 --> 0:20:00.480 look and behave precisely exactly like you do, like me 0:20:01.200 --> 0:20:01.439 or like. 0:20:01.520 --> 0:20:04.360 Kelly, or chemists are like, are they really in there? 0:20:04.400 --> 0:20:06.800 Do they actually like chemistry? Is that possible? 0:20:07.280 --> 0:20:08.320 They have to be a machine? 0:20:08.440 --> 0:20:10.520 Right, are they just lying? 0:20:10.800 --> 0:20:11.119 Yeah? 0:20:11.520 --> 0:20:12.880 We don't have a way of testing it. We don't 0:20:12.880 --> 0:20:14.960 have like a consciousness ometer. I can't pull out my 0:20:15.240 --> 0:20:17.840 hair dryer looking consciousness ometer and pointed at you and 0:20:17.880 --> 0:20:19.840 be like are you conscious? Like we don't have that. 0:20:20.320 --> 0:20:22.080 How do you know what it would look like? We 0:20:22.119 --> 0:20:23.840 don't even have the device. Why does it look like 0:20:23.880 --> 0:20:24.720 a hair dryer? 0:20:25.800 --> 0:20:28.520 At some point actual clearman is positive that it was 0:20:28.560 --> 0:20:30.480 going to look like a hair dryer, and it is 0:20:30.560 --> 0:20:33.760 kind of propagated throughout by thinking since then. But that 0:20:33.840 --> 0:20:36.200 seems about right right, Like it's kind of like a spidometer, 0:20:36.320 --> 0:20:38.240 like they, you know, cop pulls up that on the 0:20:38.240 --> 0:20:38.880 side of the road. 0:20:39.000 --> 0:20:40.879 Too much consciousness, here's your ticket. 0:20:42.560 --> 0:20:45.040 Something like that. But we don't have those and in fact, 0:20:45.200 --> 0:20:47.320 like we wouldn't even know how to build one, right, 0:20:47.400 --> 0:20:50.359 We don't even know what the relevant metrics are. Do 0:20:50.400 --> 0:20:53.280 we care about measuring brain stuff? Or is that kind 0:20:53.320 --> 0:20:56.840 of spurious? But one of the arguments kind of against 0:20:56.880 --> 0:21:02.439 philosophical zombism is the supposition that consciousness is not just 0:21:02.520 --> 0:21:05.080 this epi phenomenon, That it's not just this thing that 0:21:05.200 --> 0:21:08.119 kind of comes along for the ride over and above 0:21:08.600 --> 0:21:12.760 an organism behaving usefully in its environment and flexibly adapting 0:21:12.760 --> 0:21:16.480 to different conditions and being intelligent and seeking goals and 0:21:16.520 --> 0:21:20.159