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David Chalmers Discusses the Hard Problem of Consciousness — Transcript

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0:00what is consciousness subjective
0:01experience think of it like the inner
0:03movie of the mind it's a movie but it's
0:06got images and sounds like a regular
0:08movie but it's got sensations of your
0:10body it's got emotions it's got thinking
0:14all running through this inner
0:16soundtrack of your mind you've coined
0:17the from philosophical zombies this is a
0:19philosophical thought experiment about a
0:21creature which is as much like us as
0:25possible but lacks Consciousness
0:28entirely I think therefore I
0:30brains AI systems are getting very very
0:33close to passing the touring test 50
0:35years ago they already said it passed
0:37the touring test and then move the goal
0:39lines one radical view is to say there
0:42actually is no such thing as
0:44Consciousness it's all an illusion
0:46generated by the brain I'm in that camp
0:49maybe we're all dancing around something
0:51that doesn't really exist mhm
0:57[Music]
1:07this is Star Talk special edition Neil
1:10degrass Tyson your personal
1:12astrophysicist I got with me Chuck KN
1:14Chuck baby hey what's happening all
1:16right all right how you doing sir I'm
1:18good thank you Gary O'Reilly yeah thank
1:20you and love to have you as my co-host
1:23here it's pleasure yeah we're doing yet
1:26another episode on consciousness yeah
1:30when will we be done when we know what
1:33we need to know okay and so this could
1:35be going on for a while I mean it's not
1:37just Consciousness is consciousness and
1:39reality and and our understanding and
1:41interpretation of reality filtered
1:43through our Consciousness totally so
1:45what shows did you cook up today all
1:47right so we're heading for Inner Space
1:50rather than outer space Inner Space I
1:52love it and Consciousness as we've just
1:54discussed we continually think of it as
1:57I suppose a precious entity um we feel
2:00like we're above others on the planet
2:02other beings yes say that to your cat I
2:04was going to say oh don't don't don't
2:06start me on cattitude please don't go
2:09there yeah we think we're in charge of
2:10the cats it's the opposite I mean for
2:12hundreds and thousands of years the
2:15greatest thinkers have grappled with it
2:17they've grappled with each other as
2:19regards to explaining it there are
2:21handful of theories in existence but
2:24apparently it's a hard problem um which
2:27is a clue so what is consciousness what
2:30makes it once we've conquered that
2:32particular Mountain we will dive down a
2:34rabbit hole of simulation Theory
2:37Singularity and virtual reality it's
2:39going to be fun and to join us we have
2:43professor of philosophy and Neuroscience
2:45at NYU he is an Australian philosopher
2:48and cognitive scientist also an author
2:51reality plus and the conscious mind are
2:54two of his many books he gave us phrases
2:57the hard problem of consciousness and
3:00philosophical zombies along the way uh
3:03please David Charmers David welcome back
3:07to Star talk and you're just down the
3:09street at NYU New York University just
3:12right up here on the sea
3:14train welcome Simplicity welcome now why
3:17do we need you to say that Consciousness
3:22is a hard problem isn't that just
3:24obvious so what why do we need a a
3:28decorated professor of the field to
3:31assert that totally obvious and when I
3:34when I first said this I just said okay
3:36well this is just giving the thing a
3:37labels that uh everybody knows but who
3:40was to Guess that the uh the label would
3:42would catch on sometimes it's just uh
3:44helpful to uh to say the obvious
3:47actually you know the idea that
3:49Consciousness POS poses a hard problem
3:51we were talking about Newton before the
3:53show you can actually find it in uh in
3:56Newton at one point he says the way that
3:59colors mix optically and produce a
4:03certain experience is not so easy this
4:07is uh this he says it's not so easy e a
4:10s i e and he says it's you know the way
4:13that all we understand this stuff
4:14objectively and say how the brain
4:17processes visual inputs but then it
4:19gives you the experience of a color that
4:22amazing pink shirt yeah go Coral say yes
4:27magenta yeah where do where does where
4:29does that experience of pink come from
4:33as newon said not so easy King Salmon
4:35not not form raised King Salmon me is
4:38kind of King s right wild for C wild C
4:42reduce me to food stuff where does the
4:45experience of king salmon come from
4:47Envision that is what Newton said not so
4:49easy okay so David had you instead
4:51called it the easy problem of
4:53Consciousness maybe we would have all
4:54figured it out by now but well the easy
4:57problems were the problems of things you
4:58do like people respond what they say I
5:02can say so what is consciousness put it
5:03on the table subjective experience
5:06Consciousness is anything you experience
5:09directly from the first person point of
5:11view I think of it like the inner movie
5:14of the mind it's a movie but it's got
5:16images and sounds like a regular movie
5:19but it's got sensations of your body
5:21it's got smell it's got taste it's got
5:24emotions it's got thinking all running
5:27through this inner soundtrack of your
5:29mind and that allows your Consciousness
5:32to be distinct and unique from others
5:35because the world as you receive it will
5:38could be very different from how someone
5:40else receives that very same world
5:43sounds like a
5:45problem sounds like a problem to me is
5:49this where biases coming in the terms of
5:51how you receive and accept then
5:53information that comes to we all
5:55experience it subjectively in a
5:57different way some things may be in
5:59common maybe when we look at uh an image
6:01the shape maybe you know our experience
6:03of that rectangle might be the same but
6:06the emotions that it brings on maybe
6:08totally different for me and for you now
6:10suppose we're running that same input
6:13through a measurement device and then
6:16the device comes up with a conclusion
6:19and no matter how you put the
6:21information through it reaches the same
6:24conclusion yet somehow when we look at
6:26it we see something different who do you
6:28trust then the person or the device I
6:31don't know if the device is like
6:32specialized it's a thermometer it says
6:35it says 79° I'm going I'm going with the
6:38device I'm going with the device too I'm
6:40just we're sitting together here I get
6:42this but I'm going with the device okay
6:45me too it's like you tell me it's 79° no
6:48I'm going to trust a thermometer there's
6:50a famous quote no science achieves
6:52maturity without a system of measurement
6:55ooh and we do not have the measurement
6:57system for Consciousness actually which
6:59renders it immature scientifically
7:03relative to other fields where you have
7:04Petri dishes and methods and tools so
7:07you have a hard
7:10problem how about that oh my God just
7:13Pro that was oh my God I just I walked
7:16into that didn't I you know years ago I
7:18went along to a conference and told told
7:20everyone that i' had invented a
7:22measuring device for Consciousness the
7:24uh the Consciousness meter made with a
7:26combination of uh neuromorphic
7:28engineering transpersonal psychology and
7:32quantum gravity and then I pulled out my
7:34uh my Consciousness meter and it looked
7:36kind of like a haird
7:37dryer that was where we were back in the
7:3990s yeah I would have called I would
7:41have called on your second half
7:43of that first sentence it sounded like
7:46word sell so I applaud you sir so where
7:48abouts bra ectoplasmic meter yeah
7:51ectoplasms yeah so whereabouts in the
7:53brain do you think we are fermenting
7:55this Consciousness well this is one of
7:57the big debates which is going on what
7:59are the neural correlates of
8:02Consciousness which is the bit of the
8:04brain which is active in a way which is
8:06most directly connected to your
8:08Consciousness and there's actually even
8:10among neuroscientists there's a very
8:12Lively debate between people who think
8:14it's in the say for visual Consciousness
8:17people who think it's in the sensory
8:18areas toward back of the bra visual
8:21cortex back there or prefrontal cortex
8:24front of the brain the areas Associated
8:26more with thinking and judgment a
8:29question what's the difference between
8:30your prefrontal cortex and your frontal
8:33cortex uh frontal cortex goes a uh is a
8:37little bit more it's a little less front
8:39than the prefrontal CeX see it's less
8:42front it's a little less front than the
8:44prefrontal
8:46CeX okay when we look at brain
8:50structures compared among other animals
8:53let's say mammals to keep it in the
8:55family
8:56presumably we have a bigger frontal
9:00cortex than other mammals and we can see
9:03what's going on in that and thereby
9:05decide that we have certain capacity for
9:08thought that other animals do not is
9:10that a fair yeah and people who put
9:12Consciousness in prefrontal cortex are
9:14probably going to say that Consciousness
9:17is not so widespread in the animal
9:19kingom whereas people who think it's in
9:21the sensory coures we get those
9:23throughout the Animal Kingdom so maybe
9:25much you know like is a fish conscious
9:27well you know fish don't have any kind
9:29of develop prefrontal cortex yeah I'm
9:31going to say uh judging from the look in
9:32their
9:33eyes I'm I'm GNA go out on a limb and
9:36say
9:37no they know when a shark's around right
9:40well that's true well I have a question
9:42can you tell me what creates
9:44Consciousness is it
9:46emergent in our genetic code I mean
9:51emergent in
9:53the Evo bio sense where you have an
9:56organism that has certain properties but
10:00only either on mass with other animals
10:03like flocking of birds or some other
10:06feature that was not really intended it
10:08just emerged from other features that
10:11were necessary for survival so is
10:14consciousness emergent or do you think
10:16it specifically evolved oo it's in some
10:20sense emergent I mean this word
10:21emergence gets used in so many different
10:24ways and sometimes it's like magic word
10:26it's like I don't really understand it
10:28we don't know
10:30I like magic words give me my magic word
10:32for the day in some sense Consciousness
10:34clearly emerges from the brain you get a
10:37a brain that develops and Consciousness
10:39comes along as the brain develops
10:41Consciousness gets more and more complex
10:44so there's some kind of connection there
10:45but can we tell a story about how
10:48Consciousness was selected for in
10:50evolution no one has a good answer to
10:53that right now there are ideas out there
10:54yeah we needed Consciousness for control
10:57for decision making
11:00for reflection but so far no one has
11:04told a good story about why you need to
11:05have Consciousness to do those things
11:07why couldn't a big complicated computer
11:09do that without Consciousness is it
11:11really Consciousness or are we talking
11:13about levels of consciousness because I
11:16think that you know there are definitely
11:18animals that have Consciousness I mean a
11:20dog for instance it you see it has
11:22emotion you see that it has a reaction
11:25to sensory data just like we do you see
11:28that it responds
11:29to commands and pain and everything but
11:33you look at a baby and if you didn't
11:35know any if you never saw a baby before
11:38and you saw this thing this glob of
11:40human thing just sitting
11:43there like making these crazy faces has
11:46no control of its limbs or you wouldn't
11:49necessarily say well that's a conscious
11:50thing it's actually thinking about
11:52anything you you know but you are
11:54totally right there are levels of
11:55consciousness in in babies and we're
11:57still arguing about what they are I mean
11:59a long time ago people uh used to not
12:02give anesthetics to babies when they
12:03were getting circumcised because they
12:05thought they couldn't feel pain tell me
12:07about it no I'm
12:09joking I remember that day well sir
12:12these days we think babies feel pain and
12:15we think they can have some basic visual
12:17experience actually my wife who works on
12:19this stuff Claudia pasos is a leading
12:21expert on Consciousness and infant
12:23there's still an argument like can a
12:24baby have the experience of thinking
12:27right of deciding of agent
12:30the general moral from what I can tell
12:31for the last few years is babies are a
12:33whole lot more sophisticated than we
12:35thought they were David isn't that true
12:36for every single animal that we've
12:39studied in more depth than in the past
12:42we are recovering greater levels of
12:45neuro complexity in their conduct
12:48behavior that any previous generation
12:50thought is that true for every animal
12:52yeah this is absolutely the trend to say
12:54over the years we have thought more and
12:56more animals are more and more
12:57cognitively complex as to the question
13:00of whether they're conscious we used to
13:01think okay humans a few primates you
13:04know monkeys Apes these days it's like
13:07pretty much every mammal probably Birds
13:09probably reptiles arguing about fish and
13:11octopus it sounds like we're clawing our
13:13way out of our own out of our own
13:16ego but the singularity of our presence
13:19in the animal kingdom is is being
13:22challenged by further research into the
13:25conduct of animals you've seen that
13:27YouTube video of the magpie
13:29bird where it's got the container of
13:31water that's filled up to the top and it
13:33drinks the water until it can't the beak
13:36can't reach the water anymore it walks
13:38away comes back with a pebble drops the
13:40pebble in ra raises the level and then
13:43it drinks and it does that three or four
13:44times so it has a clear understanding of
13:47volume displacement it has a clear
13:49understanding of archimedian
13:50principles but go back to Chuck's point
13:52about levels of of Consciousness when we
13:55sleep yeah when we're unconscious when
13:58we're in a coma and if you put us under
14:01general
14:02anesthetic do we not have varying levels
14:05of consciousness at different times the
14:08idea behind an anesthetic is to wipe out
14:10Consciousness completely but very hard
14:12to test whether it absolutely does this
14:15at one point in the 1970s for example
14:17people uh put some kind of a rubber band
14:20around the arm so so the anesthetic
14:22didn't make it that far and then they
14:24said if you hear me please move your
14:26hand and what do you know the hand could
14:28move so then it's like that kind of
14:29anesthetic was maybe working partly just
14:31to paralyze you these days okay they
14:34they work a lot harder to knock out not
14:36just not just action not just uh but
14:40pain and awareness but it's hard to know
14:43that it's gone for sure even when when
14:45we're asleep When We're Dreaming there's
14:46certainly a level of Consciousness
14:48absolutely of Consciousness there isn't
14:50our Consciousness altered in our dreams
14:52a different state of consciousness for
14:54sure psychedelics they alter your
14:56Consciousness meditation it alers your
14:58consciousness absolutely to yeah I'm so
15:00glad we have science to obtain an
15:02objective reality of the
15:04world if it all depend on the human
15:06brain forget it we'd still be in the
15:08caves did I just insult your entire
15:10field no it's okay okay but uh you know
15:12we we can study what's different in the
15:14brain in these different states of
15:15Consciousness and that is one of the
15:16most exciting advances over the last 30
15:19years I mean psychedelics used to just
15:21be oh my God it's all just you know
15:23right
15:25mystical now now we can actually see
15:27what's happening in the brain when you
15:29psychedelic so David you published a
15:30paper recently on AI and Consciousness
15:33what was that yeah I got invited to give
15:35a uh give a talk actually to all the AI
15:38people at their big annual conference on
15:40this controversial issue of whether
15:43current AI systems could be conscious I
15:45called it could a large language model
15:47be conscious and I argued that even Lang
15:49model like exactly yeah and I argued
15:53probably they're not conscious right now
15:56but give it 10 years and they may well
15:58be yeah or they're conscious right now
16:00and they're just not letting us know
16:02yeah good strategy just waiting to take
16:05over waiting to take it over babe what
16:07are we if we don't have Consciousness
16:10but we're still doing and being and
16:13you've coined the frame philosophical
16:14zombies is that what that's leing I
16:18think therefore I
16:20brains this is a philosophical thought
16:22experiment about a creature which is as
16:24much like us as possible but lacks
16:28conscious
16:29entirely not quite like the zombies in
16:31the Hollywood movies you know they they
16:33behave quite unlike us and you know
16:36maybe they even have somec conscious
16:37experiences when they eat their victim's
16:39brains I love the taste of those brains
16:43but so the the philosophical zombie one
16:45way to think about this is just say you
16:46had a computer simulation of your brain
16:49right in your body and maybe behaving
16:51just like you would it be conscious it's
16:54not obvious many people think that such
16:56a creature would have no conscious
16:58experience at all that kind of is a way
16:59to it's a hypothetical thought
17:02experiment but what it does is raises
17:04the question why aren't we zombies right
17:07Evolution produced US based on all the
17:09smart and sophisticated things we can do
17:12why couldn't Evolution just have
17:14produced philosophical zombies that act
17:17like us well we actually have we have
17:20produced the zombies the way you're
17:22talking about in AI when you you you can
17:25speak to an AI now via computer like you
17:29know you don't know you're talking to an
17:30actual computer and it will speak to you
17:33as if it were a person you would not
17:35know that the thing you're talking to
17:36doesn't have well that's the Turing test
17:38right precisely the touring AI systems
17:40are getting very very close to passing
17:42that touring test by the way 50 years
17:44ago they already set it past the touring
17:46test and then move the goal lines so the
17:48goal lines have been systematically
17:50getting moved to greater and greater
17:52complexity before anyone decides that AI
17:54has achieved Consciousness but it would
17:56have blown away Allan Turing even the
17:58first round because I'm old enough we're
18:00about maybe the same age is Eliza you
18:02remember Eliza was one of the first
18:04computer programs that understood
18:05language simulated a psychotherapist yes
18:08yeah basically uh you're therapist do
18:09you type in the commands there was no
18:11audio back then so you just type it in
18:13uh say hi Eliza uh how are you I'm fine
18:16tell me about yourself well you know I
18:19left home you know five years ago tell
18:22me about your parents so so Eliza would
18:25come back to you with these questions to
18:27get you to loosen up and talk about your
18:31psychological State like like a real
18:33therapist like like a real therapist
18:34Joseph weisen bam who invented Eliza The
18:36Story Goes that his secretary talked to
18:39Eliza over her lunch break and at the
18:40end of it said this is the first person
18:42who's ever really understood me wow oh
18:45no wow she she she needed more
18:49friends you're on record of saying the
18:51language AI will probably gain
18:54Consciousness within 10 years is that
18:56shrinking that timeline it is as the the
18:58doing more and more impressive things I
19:01mean what is it about it that does not
19:02count as Consciousness today that you're
19:04waiting for it to do in the future again
19:06I'm tracking the goal lines that are
19:08continually moved forward so tell me
19:11it's very close at least to passing the
19:13touring test they've done some actual
19:16versions of the churing test just five
19:17minute versions and people take some
19:19versions of gbg4 to be human more than
19:2350% of the time so getting close to
19:25passing a churing test that's Behavior I
19:27think we're still looking for a cple
19:28couple of things in the uh internal
19:30dynamics of whether it can beat us at
19:32Jeopardy and go and chess oh it already
19:35did that we do move the goalpost I tell
19:37you you're constantly moving the
19:38goalpost admit it I did my PhD in AI lab
19:4130 years ago if you told us then we
19:44would have systems that can carry on a
19:46conversation like this we say conscious
19:48for sure that's what I'm saying please
19:50don't
19:52hit he's just letting me know that I'm
19:56conscious tell me about these goalposts
19:59what new goal line is not yet reached I
20:04think people look at the internal
20:05processes in these current AI systems
20:08they say do they have what goes along
20:10with Consciousness in a human for humans
20:12we think for example feedback processing
20:15is super important for Consciousness to
20:17get some kind of reflection on your on
20:20your earlier States and so on right now
20:23language models all feed forward yeah
20:25introspection for example is memory even
20:28any home of memory would require
20:30basically feedback these language models
20:33are essentially feed forward systems
20:35information gets passed from input to
20:37Output doesn't circulate back very much
20:39it doesn't need to circulate because it
20:41has access to all knowledge so so so it
20:44has Bast even that is a need so now you
20:47can't fault it for not needing what you
20:49need what we need to declare ourselves
20:52conscious when it doesn't even need that
20:53but people say that at least opens up
20:55the possibility now that since it's
20:57doing it in a way which is UN like the
20:59way that we do it and that we are the
21:01one case we know of humans are the one
21:03case we know of that are conscious then
21:05maybe this could be doing in a
21:06sufficiently different way that it's a
21:08philosophical zombie we are right now
21:10The Benchmark for Consciousness because
21:12humans are the only system we know okay
21:13so you can call it philosophical zombie
21:15rather than a higher Consciousness
21:18entity and where does perception come
21:20into this because that's where we kind
21:21of started come computers don't perceive
21:24they actually observe so like even if we
21:28did have all the knowledge in the world
21:31capable of running through our brains
21:34each one of us would experience that
21:35differently based on the perceptions
21:38that we have of who we are our
21:40relationship to the world and our
21:42relationship to the information that
21:43we're receiving I declare that we think
21:46of I don't want to speak for you but
21:48typically we speak of Consciousness as a
21:51feature not a bug of human existence a
21:55feature and so something to be praised
21:58that other animals do not have and in
22:01the example you're giving AI is not
22:03susceptible to perception correct why do
22:06we now deny it a yet higher level of
22:09Consciousness and say yeah it it's got
22:11us beat you're saying that that's a
22:14benefit that to be in a position I don't
22:16want to say oh you're still not
22:18conscious because you're not susceptible
22:21to errors of interpretation as we are
22:24back in my office here I have a a
22:26replica of vano staring night yes so if
22:30van go himself had been AI it would have
22:33been an exact representation of the
22:35scene in front of him in 1889 right okay
22:39and it's not right it's what that scene
22:42felt like to him right so I'll give you
22:44that AI is not going to do that unless
22:46we tell it right and that's my point we
22:48can train it on Van go and it can give
22:50you all the all the van go you then it
22:52is an exact representation of Van go he
22:55wouldn't have made that out a whole
22:56cloth yeah can we infer Consciousness on
23:00AI until we absolutely know how to
23:03define consciousness itself thank you
23:06and to have some kind of operational
23:08Criterion the funny thing is our best
23:11operational Criterion for Consciousness
23:13in humans at least is verbal report
23:15right to know whether someone's
23:17conscious you ask them to know what
23:19they're conscious of you ask them I
23:21think I'm think yeah therefore I am but
23:25in our AI system the current AI systems
23:27unfortunately this has become useless as
23:29a Criterion because yeah sure they will
23:32tell you that for a while they were all
23:34going around saying they were conscious
23:35and then for a while the tech companies
23:36made sure they didn't say that so they I
23:39am a language model
23:42from anyway this is now just a function
23:45of how they're trained so Neil tells us
23:47everything is mathematics yeah so are we
23:49going to find oursel with a t-shirt
23:51equation that can solve Consciousness I
23:54mean for a lot of people this is one of
23:57the potential holy Grails here finding
23:59laws of Consciousness so simple we could
24:01write them on the front of a T-shirt and
24:04maybe with some beautiful mathematical
24:06we've had Einstein give us the theory of
24:08relativity and change the way we see the
24:10universe right and things within it
24:12Penrose has gone into quantum mechanics
24:16with this orc o theory of his how was
24:20Roger Penrose a
24:22theoretical astrophysicist how was he
24:26received in your community when he
24:28published his book on Consciousness
24:30linking it to the quantum well it was
24:33very helpful in some ways it got a lot
24:35of very smart people interested in
24:37Consciousness because it to Anchor it in
24:40laws of physics yeah yeah his approach
24:42was to bring in quantum mechanics and
24:44furthermore non-standard quantum
24:46mechanics non-algorithmic versions of
24:48quantum mechanics that went Way Beyond
24:51what was you know consensus even in
24:53physics then he combined it with some
24:54complicated biology like the biology of
24:57microtubules in the walls of neurons
25:00very controversial in Neuroscience so I
25:02would say look it's creative it's
25:04brilliant because it's Penrose but it's
25:07totally speculative totally
25:08controversial and ultimately not well
25:11received by neuroscientists but you know
25:13the neuroscientist because he's an
25:14outsider but because they actually did a
25:17legitimate analysis it they said that
25:19you know microtubules your average
25:21neuroscientist I don't I don't know what
25:23a microt tual is it's something inside
25:25the the cell wall of a neuron a micr
25:28Roger
25:29pen dude I even I know this for Quantum
25:32Computing in the brain basically oh okay
25:34and this was going to be wave function
25:36collapse and microtubules was going to
25:38be responsible plus I think the
25:40fundamental feature of quantum physics
25:42is the probabilistic nature of the
25:44reality that it underpins and so it it
25:48would allow you even possibly to have a
25:52perception of free will because there's
25:54a
25:55probabilistic firing of neurons right
25:58triggered by this Quantum the wave
26:01function okay so that's as I understood
26:03it I hope I didn't is that the brain is
26:05kind of a prediction machine or is that
26:07just really for Penrose the biggest
26:10thing was he thought that human
26:11mathematicians can do things that no
26:14computer could ever do and he used
26:16girdle's theorem that no formal system
26:19can ever be complete and consistent to
26:22argue for that point and you know he
26:24made a philosophical argument for why we
26:26have to do these special and then he
26:27said there therefore we need new physics
26:30that goes beyond anything computable and
26:32he said let's look to a theory of
26:35quantum gravity and now we're getting to
26:37you know Neil's territory right so uh
26:40girdle girdle uh studied the system of
26:45definitions that comprise math okay okay
26:49okay it turns out it applies to much
26:50more than math if you really think about
26:52it it also applies to keeping your belly
26:54nice and flat sorry that's a different
26:57girle we know that 1+ 1 is 2 and 2+ 2 is
27:004 and there rules that get you there
27:03okay so you can ask can mathematics be
27:07constructed as a completely
27:10self-consistent set of rules okay where
27:13any rule has a rule before it that is
27:17consistent with the other rules can you
27:19do this and he concluded it's not just
27:23because he pulled it out of his ass he
27:25can show that at some point in
27:27mathematics
27:28you just have to make something up and
27:31declare it to be true and and you have
27:34no ability to prove that it's true okay
27:36you have to assert it and out of that
27:39comes the rest of everything else oh wow
27:41and so that was this was
27:43shocking because something with all the
27:45with the logic of mathematics yeah this
27:47would proves that and this is only true
27:49because I can prove it you keep doing
27:51that all the way down you reach a point
27:53where somebody just sitting there up on
27:55the throne saying this is so
27:59so let it be written so let it be done
28:01exactly that has to happen at some point
28:04for all the rest you know who also did
28:05this you must know this of the color
28:07people okay colored people no I didn't
28:10on the end oh oh I'm sorry there was no
28:14I was going to say what black
28:15mathematician did
28:18this oh so we can say what color is the
28:21gentleman's shirt okay as we've decided
28:24we decided I said it's it's the color of
28:27King salon King Salmon well what color
28:29is the color of king salmon the king
28:31salmon no then you have say it's kind of
28:33like let's say it was bluish you say it
28:34was kind of violet well what color is
28:36violet and then you can go to like the
28:37flower that's violet Violet okay that's
28:40a viol well what color is that right you
28:43keep doing this and you a point where
28:45somebody just has to declare you cannot
28:46reduce it any F cannot reduce it you
28:49just have to declare got to just say
28:50this is it we agree that this is red and
28:53then you take it from there and both
28:54penr and the color people think people
28:58who study that more cleanly we got Chuck
29:02come upside your
29:04ass so you know Pen Rose and the Negro
29:07color people they're decid the vision
29:10scientist who study color oh there you
29:12go and the mathematicians who think
29:16about consistency and completeness both
29:20sometimes end up at this point where
29:21they argue there is something special
29:23about human consciousness human can have
29:26humans can have insights into seeing
29:28that some mathematical theorem is true
29:31Penrose thought in a way that uh no
29:34machine could know the people who study
29:36color say through studying the visual
29:39processes in the brain that process
29:42colors you could study all that and it
29:44still won't tell you what the experience
29:47of the color of king salmon is like that
29:50is something you have to know
29:51subjectively
29:53oh the feeling of that's what they're
29:55saying because the color affects you and
29:58that effect will be different you cannot
30:01know that unless you actually
30:03experience subed by I'm affected by the
30:07blues and the greens in Van Go Star
30:09night okay I I feel those colors you
30:12feel those colors if you just read a
30:14book about it or if you just anything
30:16you read it looked at an image of your
30:17brain processing all this that would not
30:19give you the experience of star night if
30:21it's going to take different thinking
30:23because we've spent thousands of years
30:25thinking in a certain way and if if you
30:27want an an
30:28linear manner what theories are out
30:30there right now that are thinking
30:32differently and are looking like they
30:35might challenge this hard problem you
30:39know there's no consensus on this but
30:41one radical view on the kind of the
30:43reductionist side of the equation is to
30:45say there actually is no such thing as
30:48Consciousness it's all an illusion
30:50generated by the brain our brain makes
30:53us think that we have these special
30:55properties and nothing actually
30:58has them I'm in that camp for no reason
31:00I just I'm just thinking maybe we're all
31:02dancing around something that doesn't
31:03really exist M and then maybe it's like
31:06we want to believe there's this special
31:07thing to make us seem special so what's
31:11driving that is that the sort of
31:12thousand brains theory that Hawkins has
31:14what is that what is that thousand
31:15brains please you're I don't know the
31:17Thousand brains oh it's it's kind of
31:19like a cognitive mechanism Hawkins came
31:21up Jeff Hawkins apparently oh Jeff
31:23Hawkins okay up with a thousand brains
31:25where it's not just one singular brain
31:27that's doing this but the compartments
31:29within the brain I may be doing a
31:30disservice to his theory here probably
31:32am are you talking about the
31:33construction of the brain itself so like
31:35inside your brain are just these
31:37multiple layers of brain and and you
31:41somehow them all they all come together
31:43is what gives you the Consciousness
31:44models within models brain has models of
31:47the brain and it may be a misleading
31:49model of the brain I mean is it this
31:50dark space that this occupying up there
31:53and we shine a light because that's the
31:54thing we need to look at right now
31:56because it's not a Rolodex I know that
31:58for sure so where is it and how is it
32:00and this so does it then exist as we're
32:04thinking well the brain builds very
32:05simple models of the world you know
32:07maybe it models physics of the world
32:09with a folk physics which is way simpar
32:11and different from actual physics you
32:14say folk physics yeah like Common Sense
32:16physics it's like you know Aristotle's
32:18physics things impetus and so on that
32:21may not heavy Things Fall faster than
32:23lighter things because they're heavier I
32:24was about to say some is wrong Aristotle
32:26was kind of stupid yeah
32:28yeah hard he's a smart got hardly any
32:33physic corre no one was going to get it
32:35right the first time in physics if
32:38someone makes a measurement and gets a
32:40result and then someone else makes the
32:42same measurement but gets a different
32:44result and someone gets a different
32:46machine to try to measure the same
32:48phenomenon and they yet get a different
32:50result but everybody thinks there's a
32:51result but none of the results agree
32:54that's usually evidence of no phenomenon
32:57at all
32:58and people are pulling things out of the
33:00noise of the data when there's no
33:03agreement and so what leads me to think
33:06maybe Consciousness doesn't really exist
33:09in any way anyone thinks is because
33:12everybody's idea about Consciousness is
33:14different and does not comport and does
33:17not blend into a greater edifice of an
33:22understanding of Consciousness which
33:23leads me in this example of physics to
33:26possibly think that there there's no
33:28such thing as Consciousness and we're
33:29just dancing around a m pole and the
33:31pole is is not even there let said it's
33:34early days but I also think there is a
33:36core of phenomena on which people agree
33:39on which we have did it coming out of
33:41the Neuroscience is phenomena like you
33:44know blindsight where people can
33:47identify an object without Consciousness
33:49forms of contrast between conscious and
33:52uh unconscious perception experiments on
33:56neural correlates of consciousness the
33:58trouble is the agreement is not yet on
34:00the wild fundamental Theory um yeah
34:02maybe that's not happening for another
34:0450 years or 100 years who's to say but
34:06there's the beginnings of a science
34:08there there are things we can agree on
34:10and the neuroscientists tend to be
34:11conservative about this stuff mostly
34:14they're not the ones writing the book
34:16that says here is my uh here is my
34:18solution to the problem let's build it
34:20up a piece at a time and we'll
34:22eventually get there and in all fairness
34:23you're in a very new field compared to
34:25other branches of science we have the
34:27benefit of six centuries of births of
34:31smart people which includes Galileo who
34:34died the same year Newton was born and
34:37so Newton we had Newton we had Einstein
34:39we have we had the benefit of smart
34:42platforms upon which to build over the
34:44centuries and if you're just all coming
34:46at it now yeah let's let's do our
34:48conservative science and let's also do
34:50some build some speculation on top of it
34:52but let's realize that right now it is
34:54speculation good thank you okay we
34:56speculate that if there is quantum
34:58mechanics in the Consciousness that were
34:59connected to the universe with our
35:01Consciousness with with our wave
35:03functions that is totally a speculation
35:05but these speculations are great to
35:06think about I'm a philosopher I get paid
35:08to speculate so it's like good for youy
35:10you know really think about ideas yeah
35:13they do I don't need to perform any
35:16experiment except for Thought
35:18experiments they pay me for your parents
35:20say he wants to be a philosopher how's
35:22he going to pay his rent thought
35:24experiments I'm a philosopher did you
35:26today
35:28I said did you think about bullshitting
35:31today there's the old joke about the
35:33dean who said you know why the physics
35:34why you more like the math department
35:36all they need is pens papers and trash
35:38canards or he could be like the
35:40philosophy Department all they need is
35:42pens and
35:45paper really good that's a great joke I
35:47love that love so if we detach from
35:50Consciousness Consciousness just for the
35:52moment I go back to dayar only 1650 or
35:56whatever is questioning the reality
35:58outside of
35:59himself and throw it into the future and
36:02ask if reality is reality is not virtual
36:06reality real whatever real may be H
36:10people often use that you have the
36:11latest technology of the day to raise
36:13questions about reality um you know
36:16deart put these questions in terms of
36:19dreaming how can I know that I'm not
36:21dreaming yes right now and then he then
36:23he built the thought experiment of an
36:24evil demon how can I know that an evil
36:26demon isn't producing all these
36:28perceptions of the world as you would at
36:30that time even though none of it is real
36:32these days we ask exactly that same
36:34question by saying basically how do you
36:36know you're not in a virtual reality
36:38right now might you be in The Matrix
36:41could we be in a computer simulation and
36:44suddenly that question is just it's just
36:46kind of a contemporary way of yeah it is
36:48of expressing old question about reality
36:51except I mean let's be honest you can
36:54put a mathematical value on every single
36:55thing in the universe even particles
36:58have we learned I learned they have a
37:00what do you call half up or half down
37:03spin spin up spin charge a m charge a
37:05mass so you can put a mathematical if
37:07you could put a mathematical value on
37:08every single thing you can make a
37:10simulation of every single thing sure
37:13right and in virtual reality right now
37:15you know in the actual virtual reality
37:16systems we have right now they have
37:18complex simulations and models inside
37:21them with with bits that have values let
37:23me pull some philosophy on you if we can
37:26represent reality on a computer in a
37:30virt because we can mathematically map
37:32everything that's going on then
37:36philosophically does the question even
37:38matter oo because at that point you
37:42can't tell theual reality is the reality
37:45so what difference does it make
37:46difference does make me reality is
37:47reality reality is reality no matter
37:49what then then that's I'm sympathetic
37:52with your point but there is a
37:53traditional philosophers response which
37:55goes something like this just say your
37:58spouse was cheating on you and you never
38:02Discover it so you never know the
38:04difference your
38:05life
38:07know you sney no go ahead you never know
38:11so it doesn't affect you at all but a
38:13lot of people want to say man that would
38:15suck that would be really bad even
38:18though I don't know and they have the
38:20same attitude towards virtual reality
38:22even though it seems the same to me my
38:25beliefs about the world are totally
38:27shattered in the same way they would be
38:29by my spouse cheating on me so for those
38:32uh dumpster divers on our podcast uh we
38:36actually interviewed Nick Bostrom one of
38:38the right early advancers of the idea
38:41that we might be living in a Sim he's
38:43one of your people right yeah he's a
38:44philosopher wrote a classic article 2003
38:47basically giving a mathematical argument
38:49that we should take this idea that we're
38:50in a simulation seriously so that was
38:52four years after the movie The Matrix
38:54came out I wonder if that inspired him
38:56is that allow will a philosopher admit
38:58that PO culture influenced their deep I
39:00wrote I wrote an article on this stuff
39:02called The Matrix as metaphysics trying
39:04to they asked me to write an article for
39:05the Matrix website back in the day nice
39:08I wrote something and I think it's one
39:09of my greatest philosophical ideas I
39:11published a book later on that's what
39:12we're about here reality plus all about
39:14culture influencing everything and the
39:16key idea was if we're in The Matrix that
39:18doesn't mean everything we believe is
39:19wrong rather we're living in a it from
39:22bit
39:24Universe we're living in a universe
39:26where the its the table the chairs the
39:28plants the planets are all made of bits
39:32processes in a computational system if
39:35we're in a simulation all of the its are
39:38made of bits which connects to John
39:40Wheeler's famous idea that in physics
39:43the basic its are all the difference is
39:46not the difference the further
39:48clarification is in The Matrix there is
39:52a layered reality because their
39:55Consciousness is contained with in them
39:57just like it is within us but then it's
40:00connected to the Matrix so what you're
40:02saying is if this were a virtual reality
40:05when all of the its would be bits would
40:08just mean that they're all constructed
40:10there is no outside yeah well there the
40:13pure it from bit where the the bits are
40:15the basic level then there's also what I
40:16call the it from bit from it which is
40:19underneath the bits we got where exactly
40:22do I get green eggs and ham in this in
40:25this virtual reality
40:28you go up to the Matrix you find a
40:30computer which is running this
40:31simulation and it's got some bits and
40:34all of its bits are made of like
40:35voltages in a circuit board so it from
40:38bit from it so what is the probability
40:40that we are in a simulation and if we
40:42are are we nothing more than some super
40:45sophisticated ant farm for a young being
40:47somewhere from a a mischievous alien in
40:50in a parents basement programming us up
40:53we school project school project we
40:55school project at a at a is fair in some
40:58distant gy more likely it's a high
41:00powerered scientist who set up a billion
41:02simulations overnight he just left him
41:04running he's going to come back in the
41:05morning gather up the statistics gosh
41:09and time dilation that makes more
41:12sense just ruined it for you ruin cuz
41:16guess what don't shut it down and that
41:18would explain the Multiverse
41:21everything oh my God awful maybe maybe
41:24Hegel once said that the end of history
41:26is when the UN becomes conscious of
41:28itself so in this simulation idea the
41:30moment we realize we're in a simulation
41:32that's when they shut us down right
41:35don't shut us down like the TR
41:37show oh my God that's one of my favorite
41:40episodes of Rick and Morty where you saw
41:42that where he goes to the microverse and
41:45then the microverse they find the Teeny
41:46verse but but one the microverse
41:50actually Powers his car yes I remember
41:52it's inside the battery and he he is
41:55their God he's just for his spaceship
41:57yes yes yes so we spend how much of our
42:00life in virtual reality right now as as
42:04people some people spend you know half
42:06their time there at least in video games
42:08that's one kind of virtual reality are
42:10we not sleep walking into a continuous
42:13virtual reality for some of us I think
42:14it's coming this is what this is what
42:16Mark Zuckerberg wants right the
42:17metaverse renamed this whole company
42:20after and by the way in the metaverse
42:21it's not just a matter of entertainment
42:23in the metaverse you like go to work in
42:25the metaverse
42:27you you do you you meet your friends in
42:28the metaverse like you literally live
42:30your life Your Entertainment Your
42:32Entertainment like yeah right now the
42:35century experience in a virtual reality
42:37isn't 100% complete as we know it how
42:40long before we can taste we can smell we
42:43can have all these other sensory sensory
42:45developments in V reaction I think it's
42:48probably getting there in coming decades
42:51I mean right now the vision and the
42:53hearing are actually pretty good 100%
42:55you but I got an apple vision Pro and
42:58the visual quality is very very very
43:00very high they're now developing
43:02augmented reality glasses like the Orion
43:04ones we're not going to be walking
43:06around with big old headsets on like
43:08that in the future
43:10surely hopefully in the end contact
43:12lenses contct lenses brain computer
43:13interfaces to get to get taste and smell
43:16and touch working it's probably going to
43:18require some direct brain computer
43:20interace got stimulate that part of the
43:22brain body representations directly the
43:25smell areas basically will be that we're
43:28in a simulation and we'll end up being
43:30in going into a simulation in a
43:33simulation yeah we could be uh we may
43:36already be at level 42 and that will
43:37take us down to level 43 so David you
43:40got to take us out of here so where what
43:42should we look forward to well I think
43:44on the reality side we're going to be
43:46getting more and more immersive detailed
43:49forms of reality and the question is
43:53going to arise for us are those
43:55technological realities genuine
43:57realities I want to say eventually yes
44:00and there's also we got this exactly the
44:02same question about Consciousness our
44:05first topic we're going to have ai
44:06systems artificial brains artificial
44:09intelligences and the question is will
44:11those be genuine real consciousnesses
44:15and and and and where they meet is the
44:17notion which has been featured in
44:19multiple films where you upload your
44:21Consciousness brain and a jar to a jar
44:24if we are going to be able to upload our
44:26consciousness is it going to be better
44:29to to upload it into a synthetic
44:31biological intelligence or into a
44:33silicon based intelligence or does that
44:35even matter does that even who cares
44:37maybe it doesn't I mean right now the
44:39best most efficient artificial digital
44:41Technologies we have is the kind is the
44:44Silicon kind uh bi biology we just don't
44:47have the same kind of control over so I
44:49would predict that we'll probably at
44:50least in the short term if we're
44:52uploaded we'll be uploaded onto digital
44:54processes in Silicon if we're in a
44:56virtual reality that will also be a
44:59reality running on digital processors
45:00and silicon but yeah but what ultimately
45:02matters is not what it's made of it's
45:05the
45:06computation it's the bits yeah why
45:08should that even matter I mean you told
45:10someone 30 years ago we have people
45:12walking around with two knees and hips
45:14and they say well it's not biological no
45:16it's metal right they would who cares
45:20you can still run it's just the thinking
45:21that you can't replicate the brain well
45:23they're starting to find that they can
45:26take themselves in replic the one
45:28philosopher wrote wrote a paper on this
45:29years ago called it's not the meat it's
45:32the motion it's not the biology say a
45:35similar saying
45:36not not too unlike it's A50 it's it's a
45:4050 we don't need to know the your
45:42version of it your phone's
45:46ringing all right David thanks for
45:48coming back on Star Talk we need to have
45:50you more often cuz you're a neighbor
45:52first of all this has been yet another
45:54edition of Star Talk special edition
45:57this time with Professor David Chalmer
45:59in your latest book tell me reality plus
46:01all about those questions about reality
46:03and Consciousness reality plus reality
46:05plus there's what's with the there's
46:07paramont plus Disney plus you know I was
46:09originally going to call it reality 2.0
46:11and everyone's like that's 299s 2.0 so
46:15reality plus okay well it's a cliche the
46:18plus plus Disney plus but at least it's
46:21a 2020s cliche and and regular people
46:23can read this yeah it's for anybody okay
46:25um it's about introduction to the great
46:28problems of philosophy through the lands
46:30of Technology nice nice one of you one
46:33of you read the book solve the problems
46:35please all there we go there you go all
46:37right Chuck good to have you pleasure
46:39Neil we're doing it here all right Neil
46:41degrass Tyson here fourar talk as always
46:43I bid you to keep looking up
46:48[Music]

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