Roger Penrose: Physics of Consciousness and the Infinite Universe | Lex Fridman Podcast #85
the following is a conversation with Roger Penrose physicist mathematician and philosopher at University of Oxford he has made fundamental contributions in many disciplines from the mathematical physics of general relativity and cosmology to the limitations of computational view of consciousness in his book the emperor's new mind roger writes that quote children are not afraid to pose basic questions that may embarrass us as adults to ask in many ways my goal with this podcast is to embrace the inner child that is not constrained by how one should behave speak and think in the adult world Roger is one of the most important minds of our time so it was truly a pleasure and an honor to talk with him was recorded before the outbreak of the pandemic for everyone feeling the medical psychological and financial burden of the crisis I'm sending love your way stay strong or in this together we'll beat this thing this is the artificial intelligence podcast if you enjoy it subscribe on YouTube 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versions of streaming websites like the Japanese Netflix or the UK who expressvpn works on any device you can imagine I use it on Linux shout out to a bond to Windows Android but it's available everywhere else to once again get it at expressvpn comm slash Lex odd to get a discount and to support this podcast and now here's my conversation with Roger Penrose you mentioned in conversation with Eric Weinstein on the portal podcast that 2001 Space Odyssey is your favorite movie which aspect if he could mention of its representation of artificial intelligence science engineering connected with you there also seems there which is so amazing and how they science was so well done I mean people say oh no you interstellar is the this amazing movie which is the most scientific movie but I thought it's not a patch on 2001 I mean 2001 they really went into all sorts of details regarding you know getting me freefall well done and everything I thought it was extremely well done so just the details or memorizing and also things like scene where at the beginning they have these and said sort of human ancestors which is sort of right sort of Eames eggs becoming monolith yes and well it's the one where he throws the bone up into the air and then it becomes this I mean there's just an amazing sequence there what do you make of the monolith does it have any scientific or philosophical meaning to you this kind of thing marks innovation not really that comes from arthur c clarke I was a great fan of Ossie Clark so it's just a nice plot device yeah well that plot is excellent yes yeah so how nine thousand decides to get rid of the astronauts because he it she believes that they will interfere with the mission that's right no it's this view I don't know whether I disagree that question in a certain sense he was telling you it's wrong see the the machine seemed to think it was superior to the human and so it was entitled to get rid of the human beings and run the show itself what do you think how did the right thing do you think how's flawed evil or if we think about systems like how would we want how to do the same thing in the future what was the flaw there well you're basically question touching on questions you see it's just one supposed to believe that how I was actually conscious I mean it was played rather that way that's know how and was a conscious being because Hal showed some pain some cognizant the hell appeared to be cognizant of its of what it means to die yes and therefore had an inkling of cautious yeah I mean I'm not sure that aspect of it was made completely clear whether Hal was really are just a very sophisticated computer which really didn't actually have these feelings and somehow but you're right it didn't like the idea being turned off how does it change things if how was it wasn't conscious well it might say that it would be wrong to turn it off if it was actually conscious I mean these questions arise if you think I mean AI one of the ideas it's sort of a mixture in a sense you say if it's trying to do everything a human can do and if you take the view that consciousness is something which would come along when the computer is sufficiently complicated sufficiently whatever criteria you used to characterize its consciousness in terms of some can come national criterion so how does consciousness change our evaluation of the decision the hell made it's not to say that people have been confused about this because if they say these machines will become conscious but just simply because it's the degree of computation and when you get beyond that certain degree of computation it will become conscious then of course you have all these problems I mean you might say well one of the reasons you're doing AI is because you understand the device at some distant planet and you don't want to send a human out there because then you'd have to bring it back again and that's cost you far more than just sending it there and leaving it there but if this device is actually a conscious entity then you have to face up to the fact that that's immoral and so the mere fact that you're making some AI device and getting that thinking that removes your responsibility to it would be incorrect and so this is a kind of plot floor and that kind of viewpoint I'm not sure how you know people who take it very seriously I'm gonna have this curious conversation with with I'm going to forget names and I'm afraid because this is what happens to me in the wrong moment I've said I'd Douglas have said this after and he's written this book god I wish I liked I thought it was a fantastic book but I didn't agree with his conclusion from girdle's theorem I think he got it wrong is he well just tell you my story you see because I'd never met him and then I knew I was going to meet him at the occasion IRS she's coming anyone to talk to me and I said that's fine and I thought in my mind well I'm going to paint him into a corner you see use his arguments to convince him that certain numbers are conscious you know some integers large enough integers are actually conscious and this was going to be my reductio ad absurdum so i started having this argument and he simply leptin to the corner he didn't even need to be painted into it he took the view that certain numbers were conscious I thought that was a reductio ad absurdum but he seemed to think it was perfectly reasonable point of view with out the absurdum there yes interesting but the thing you mentioned about how is the intuition that a lot of the people at least in the artificial intelligence world had and have I think they don't make it explicit but that if you increase the power of computation naturally consciousness will emerge yes I think that's what they think but basically that's because they can't think of anything else well that's right and so it's a reasonable thing I mean you think what the brain do what does do a lot of computation I think most of what you actually call computation is done by the cerebellum I mean this is one of the things that people don't much mention and when I come to this subject from the outside and certain things strike me which you hardly ever hear mentioned em you hear mentioned about the left-right business they move your right arm that's you're on the left side of the brain and and so on and all that sort of stuff and it's more than that if you you have this plots of different parts of the brain they're they're two of these these things called the homunculus which you see these pictures of a distorted human figure and showing different parts of the brain controlling different parts of the body and it's not simply things like okay the right hand is controlled and since both sensory and motor on the left side left hand on the right side it's more than that vision is at the back basically your feet at the top I mean so it's about the worst organization you can imagine right yeah so it can't just be a mistake in nature there's something going on there and this is made more pronounced when you think of the cerebellum the cerebellum has when I was first thinking about these things I was told it had half as many neurons or something they're bad comparable and now they tell me it's got far more neurons in the cerebrum then cerebrum is this sort of convoluted thing at the top people always talk about cerebellum is this thing just looks a bit like a ball of wool to the back underneath it's got more neurons it's got more connections computationally it's got much more going on than this friend the cerebrum but as far as we know although it's slightly controversial the cerebellum is entirely unconscious so the actions you have a pianist who complains incredible piece of music and you think of any moves this little finger until this was key to get a hit at just the right moment does he or she consciously will that movement no ok the consciousness is coming in it's probably to do with the feeling of the piece of music that's being performed and that sort of thing which is going on but the details in what's going on are controlled I would think almost entirely by the cerebellum that's where you have this precision and they're they're really detailed once you get I mean you think of a tennis player or something does that tennis player think exactly harder which muscles should be moved in what direction and so of course not but he or she will maybe think well if the ball is angled in such a way in that corner there will be tricky for the opponent and the details of that are all done largely with the cerebellum that's where all the precise motions but it's unconscious so why is it interesting to you that so much computation is done in the cerebellum and yet is unconscious because it doesn't it's it's the view that somehow it's computation which is producing the consciousness and it's here you have an incredible amount of computation going on and as far as we know it's completely unconscious so why what's the difference and I think it's an important thing what's the difference why is the cerebrum but all this very peculiar stuff that very hard to see on a computational perspectives like having me everything have to cross over under the other size and do something which looks completely inefficient and you've got funny things like the frontal-lobe when the prett are where did we call the Louvre and the place where they come together you have the different parts the control if you wanted to do with motor and the other to do with sensory and they're sort of opposite each other rather than being connected by a nuclear pie it's not just though you've got electrical circuits there's something else going on there so it's it's just the idea that it's like a complicated computer it just seems to me to be completely missing the point there must be a lot of computation going on but the cerebellum seems to be much better at doing that then the cerebrum is so for sure I think what explains it it's as like half hope and half we don't know what's going on and therefore from the computer science perspective you hope that a Turing machine can be perfectly can achieve general intelligence well you have this wonderful thing about during and girdle and church and carry and various people particularly Turing and I guess post was the other one these people who develop the idea of what a computation is and there were different ideas of what a computer developed differently I mean church's way of doing it was very different from Turing's but then they were shown to be equivalent and so the view emerged that what we mean by a computation is a very clear concept and one of the wonderful things that during did was to show that you could have what we call the universal Turing machine it you just have to have a certain finite device okay it has to have an unlimited storage space which is accessible to it but the actual computation if you like is performed by this one universal device and so the view comes away well you have this universal Turing machine and maybe the the brain is something like that a universal Turing machine and it's got maybe not an unlimited storage with a huge storage accessible through it and this model is one which is what's used in ordinary computation it's a very powerful model and the universalness of computation it's very useful you can have some problem and you may not see immediately how to put it onto a computer but if it is something of that nature then there were all sorts of sub programs and subroutines when all the I mean I learned a little bit of computing when I was when I was a student but not very much it was enough to get the general ideas and there's something really Pleasant about a formal system like that yeah well you can start discussing about what's provable what's not these kinds of things and you've got it you know a notion which is an absolute notion this notion of computability and you really address when things what mathematical problems are computed ly solvable and what chance so and it's a very beautiful area of mathematics and it's a very powerful area of mathematics and it underlies the whole sort of once I have their principles of computing machines that we have today could you say what is Gaydos and completeness theorem and how does it maybe also say is it heartbreaking to you and how does it interfere with this notion of computation preciousness sure where the ideas basically ideas which I formulated in my first year as a graduate student in Cambridge I did my undergraduate work in mathematics in London and I had a colleague Ian Percival we used to discuss things like computational logical systems quite a lot I'd heard about girdles theorem a bit worried by the idea that it seemed to say there were things in mathematics that you could never prove and so when I went to Cambridge as a graduate student I went to various courses you see I was doing pure mathematics I was doing algebraic geometry of a sort a little bit different from my supervisor in people but it was an area and I was interested I got particularly interested in three lecture courses that were nothing to do with what I was supposed to be doing when was the course by Hermann Bondi on Einstein's general theory of relativity which was a beautiful course he was a an amazing lecturer brought these things alive absolutely and now that was a course on quantum mechanics given my great physicist Paul Dirac very beautiful course in a completely different way it was he was very kind of organized and never got excited about anything seemingly but it was extremely well-put-together and I found that amazing too third course there was nothing to do with what I should be doing was a course on mathematical logic I got I say my discussions were being Percival was incompleteness theorem already deeply within mathematical logic space was were you introduced I was introduced to it in detail by the course but Burstein and he it was two things he described which were very fundamental to my understanding one was Turing machines and the whole idea of computability and all that so that was all very much part of the course the other one was the girl of theorem and it wasn't what I was afraid it was to tell you there were things in mathematics you couldn't prove it was basically and he phrased it in a way which often people didn't and if you read Douglas Hofstadter's book he doesn't you see but Steen made it very clear and also not in a sort of public lecture that he gave to a mathematical I think it may be the atom Society one of the mathematical undergraduate societies and he made this point again very clearly that if you've got a formal system of proof so suppose what you mean by proof is something which you could check with a computer so to say whether you've got it right or not you've got a lot of steps have you carried this computational procedure well following the proof steps of the proof correctly that can be checked by an algorithm by a computer so that's the key thing now what have to now you see is this any good if you've got an algorithmic system which claims to say yes this is right this you've proved it correctly this is true if you've proved it if you made a mistake it doesn't say it's true or false but if you have if you've done it right then the conclusion you've come to is correct now you say why do you believe it's correct because you've looked at the rules and you said well okay that one's all right yeah and that one's all right what about that harm not yeah I see I see why it's all right okay you go through all the rules you say yes following those rules if it says yes it's true it is true they've got to make sure that these rules are ones that you trust is if you follow the rules and it says it's a proof is the result actually true right and that your belief that's true depends upon looking at the rules and understanding them now what girl shows that if you have such a system then you can construct a statement of the very kind that it's supposed to look at a mathematical statement and you can see by the way it's constructed and what it means that it's true but not provable by the rules that you've been given and it depends on your trust in the rules do you believe that the rules only give you truth if you believe the rules on you give you truth then you believe this other statement is also true I found this absolutely mind-blowing when I saw this it blew my mind oh my god you can see that this statement is true it's as good as any proof because it only depends on your belief in the reliability of the proof procedure that's all it is and understanding that the coding is done correctly and it enables you to transcend that system so whatever system you have as long as you can understand what it's doing and why you believe it only gives you truths then you can see beyond that system now how do you see beyond it what is it that enables you to transcend that system well it's your understanding of what the system is actually saying and what the statement and you've constructed is actually staying just this quality of understanding whatever it is which is not governed by rules it's not a computational procedure so this idea of understanding is not going to be within the rules of the sort of within the formal system yes yes rules anyway yeah because you have understood them to be rules which only give you truths they be no point in it otherwise I'm a people say well ok this is what this one said the rules as good as any other well it's not true you see you have to understand what the rules mean and why does that understanding of the mean give you something beyond the rules themselves and that's that's what it was that's what blew my mind it's somehow standing why the rules give you truths enables you to transcend the rules so that's where I mean even at that time that's already where the thought entered your mind that the idea of understanding or we can start calling it things like intelligence or even consciousness is outside the rules yes since I've always concentrated on understanding you know people say people somebody knows well we know but about creativity that's something a machine can't do is great well I don't know what is creativity and I don't know you know somebody can put some funny things on a piece of paper and say that's creative and you could make a machine do that is it really creative I don't know he said I worry about that one I sort of agree with it in a sense but it's so hard to do anything with that statement but understanding yes you can you can make go see that understanding whatever it is and it's very hard to put your finger on it that's absolutely true can you try to define or maybe dance around a definition of understanding to some degree but I don't often once it's about this but there is something there which is very slippery it's something like standing back and it's got to be something you see it's also got to be something which was of value to our remote ancestors because I sometimes there's a cartoon which I drew sometimes showing you how all these there's a in the foreground you see this mathematician just doing some mathematical theorem this little bit different job in that theorem but let's not go into that he's trying to prove some theorem and he's about to be eaten by a saber-toothed Tigers he's hiding in the in the undergrowth you see and in the distance you see his his cousins building growing crops building shelters domesticating animals and in this light foreground you see they built a mammoth trap and this poor old mammoth was falling into a pit you see and all these people around him are about to grab him you see and well you see those are the ones who the quality of understanding which goes with all the it's not just a mathematician doing some mathematics this understanding quality is something else which has been a tremendous advantage to us not just to us see I don't think consciousness is limited to humans that's the interesting question at which point if it is indeed connected to the evolutionary process yeah at which point is we pick up this very hard question it's certainly I don't think it's primates you know you see these pictures of African hunting dogs and how they they can plan amongst themselves how to catch the antelopes didn't some of these and David Attenborough films I think this probably was one of them and you can see they're hunting dogs and they divide themselves into two groups and they go in two routes two different routes one of them goes and they sort of hide next to the river and the other group goes around and they start yelping at these then embark I guess whatever noise hunting dogs do the antelopes and they sort of round them up and they chase them in the direction of the river and they're the other ones just waiting for them just to get because this when they get to the river it slows them down and so they pounce on them so they've obviously planned this all out somehow I have no idea how and there is some element of conscious planning as far as I can see I don't think it's just some kind of there's so much of AI these days they call bottom-up systems is it yeah where you have neural networks and they and they you give them a zillion different things to look at and and then they sort of you can choose one thing over another this because it's seen so many examples and picks up on the wrong signals which your mom may not even be conscious of and that doesn't feel like understanding there's no understanding and that whatsoever so well you're being a little bit human centric so well what exactly I'm not with the dogs Emma no you're not sorry I'm not human centric but I misspoke by a la biologie centric is it possible that consciousness would just look slightly different well I'm not saying it's biological because we don't know all right I think other examples of the elephants is a wonderful example to where they it's just I think this was about that's number one well they the elephants have to go from along with the troop of them have to go long distances and the leader of a troop is a female they are apparently and this female that she had to go all the way from one part of the country to another and at a certain point she made a detour and they went off in this big detour all the troop came with her and this is where her sister had died and there were her bones lying around and they go and pick up the bones and they hand it round and they caress the bones and then they put them back and they will go back again how am i doing that's so interesting I mean there's something going on there's no clear connection with natural selection there's just some deep feeling going on there we have to do with their conscious experience and I think it's something that your overall is advantageous a natural selection but not directly to do with natural selection I like that there's something going on and go on going on there yeah like I told young Russian so I tend to romanticize all things of this nature that that it's not merely cold hard computation perhaps I could just slightly answer your question you were asking me what is it there's something about sort of standing back and thinking about your own thought processes I mean there is something like that in the girdle thing because it's just you're not following the rules you're standing back and thinking about the rules and so there is something that you might say you think about you're doing something that you think what the hell am i doing and you sort of stand back and think about what it is that's making you think such a way just take a step back outside this the game you've been playing yeah you back up and you think about yeah you're just not playing the game anymore you're thinking about what the hell you're doing in playing this game and that's that's somehow it's it's not very precise descriptive but somehow feels very true that that's somehow understandings yeah this kind of reflection a reflection yes yeah there is some it's a bit hard to put your finger on but there is something there which I think maybe could be unearthed at some point and see this is really what's going on why conscious beings have this advantage what it is that gives them an advantage and I think it goes way back I don't think we're talking about the hunting dogs and the elephants that's pretty clear that octopuses have the same sort of quality and we call it consciousness yeah I think so seen enough examples of the way that they behave and the evolution route is completely different does it go way back to some common ancestor or did it come separately my hope is it something simple but the hard question if there's a hardware prerequisite you know we have to develop some kind of hardware mechanisms and our computers like basically as you suggest I'll get to in a second we kind of have to throw away the computer as we know today yeah the deterministic machines we know today is it tried to create it I mean why my hope of course is not but well I should go really back to the story which instance I'm finished because I went to these three courses you see when I was a graduate student and so I started to think I'm really I'm a pretty view what you might call a materialist in the sense of thinking that there's no kind of mystical or something around which comes in from who knows where you still that yeah you still throw your life into me I don't like the word materialist because this is just we know what material is and that's that is what is a bad word because there's no mystical it's not some mystical something which is not not treatable my science it's so beautifully put just a pause on that for a second your materialist but you acknowledge that we don't really know what the materialist that's right I mean I like to call myself a scientist that's the first but it means that yes we see the question goes on here so I began thinking okay if consciousness or understanding is something which is not a computational process what can it be and I knew enough from my undergraduate work I knew about Newtonian mechanics and I knew how basically you could put it on a computer there is a fundamental issue which is it important or not that computation depends upon discrete things so using discrete elements whereas the physical laws depend on the continuum now is this something to do with it is it the fact that we use the continuum in our physics and if we model our physical system we use discrete systems like ordinary computers I came to the view that that's probably not it I might have to retract on that someday but the view was no you can get close enough it's not altogether clear I have to say but you can get close enough and you know when to this course and I'm Bondy on general relativity and I thought well you can put that on a computer because that was a long time before people and I've sort of grown up with this how people have done better and better calculations and they could work out black about black holes and they can then work out how black holes can interact with each other spar around and what kind of gravitational waves can add and there's still a very impressive piece of computational work how you can actually work out the shapes of those signals and now we have LIGO seeing these signals and they say yeah there's this black hole spiraling through each other this is just a vindication of the power of computation in describing einstein's general as if it a so in that case we can get close we would computation we can get close to our understanding of the physics you can get very very close now is that close enough you see and then I went to this course by Dirac they see I think it was the very first lecture that he gave and he was talking about the superposition principle and he said if you have a particle you usually think of particle can be over here or over there but in quantum mechanics it can be over here and over there at the same time and you have these states which involve a superposition in some sense of it different locations for that particle and then he got out his piece of chalk some people say broke it into as a kind of illustration of how the piece of chalk might be over here and over there at the same time and he was talking about this and I my mind wandered I don't remember he what he said well I can remember he's just moved on to the next topic and something about energy he'd mentioned which I had no idea what had to do with anything and so I'd been struck with this and worried about it ever since it's probably just as well I didn't hear his explanation because it was probably one of these things to calm me down and not worry about it anymore it's in my case I've worried it about it ever since so I thought maybe that's the catch there is something in quantum mechanics where are these super positions become one or the other and that's not part of quantum mechanics there's something missing in the theory the theory is incomplete it's not just incomplete it's in a sentence that's not quite right because if you follow the equation the basic equation of quantum mechanics that's the Schrodinger equation you could put that on a computer too there are lots of difficulties about how many parameters you have to put in so on it can be very tricky but nevertheless it is a computational process modulo this question about the continuum that's before but it's not clear that makes any difference so our theories of quantum mechanics maybe missing the same element that the universal Turing machine is missing about consciousness yes yeah this is the viewer held is that you need a theory and that that what people call the reduction of the state or the collapse of the wavefunction which you have to have otherwise quantum mechanics doesn't relate to the world we see to make it relate to the world we see you've got to break the quantum you've got to break the Schrodinger equation Schroeder himself was absolutely by this idea he's owned his own equation I mean that's why he introduced this famous Schrodinger's cats as a thought experiment he's really saying look this is where my equation leads you into it there's something wrong something we haven't understood which is basically fundamental and so I was trying to put all these things together and said well it's got to be the non computability comes in there and I also can't quite remember right when I thought this but it's when gravity is involved in quantum mechanics it's the combination of those two and that's that point when we you have good good reasons to believe this this came much later but I have good reason to believe that the principles of general relativity and those of quantum mechanics most particularly it's the basic principle of equivalence which goes back to Galileo if you fall freely you eliminate the gravitational field so you're imagine Galileo drawing dropping his big rock and his little rock from the Leaning Tower whether he actually ever did that or not pretty irrelevant and as the rocks fall to the ground you'd have a little insect sitting on one of them looking at the other one and it seems to think oh there's no gravity here of course it hits ground and then realized something's difference going on but when it's in freefall the gravity has been eliminated Galileo understood that very beautifully he gives these wonderful examples of fireworks and you see the fireworks and explode and you see the sphere of sparkling fireworks this remains a sphere as it as though there were no gravity so he understood that principle but he couldn't make a theory out of it Einstein came along used exactly the same principle and that's the basis of Einstein's general theory Elizabeth II know there is a conflict this is something I did much much later so this wasn't those days that's much later you can see there is a basic conflict between the principle of superposition I think that Dirac was talking about and the principle of general Co very well principle of equivalence gravitational fields equivalent to an acceleration P pause for a second what is the principle of equivalence it's this Galileo principle that we can eliminate at least locally you have to be in a small neighborhood because you see if you have people dropping rocks all around the world somewhere you can't get rid of it all at once but in the local neighborhood you can eliminate the gravitational field by falling freely with it and we now see this with astronauts and they don't you know the earth is right there you can see the great globe of the earth right beneath them but they don't care about it they as far as they're concerned there's no gravity they fall freely within the gravitational field and that gets rid of the gravitational field and that's the principle of equivalence so what's the was the contradiction what's the tension with superposition uh well what so we just a backtrack for a second just to see if we can weave a thread through it all yes so you wish she started to think about consciousness as potentially needing some of the same not mystical but some of the same imagine see this is a complicated story so you know people think oh I'm drifting away from the point of something but I think it is a complicated story so what I'm trying to say I mean I try to put it in a nutshell it's not so easy I'm trying to say that whatever consciousness is it's not a computation yes it's not a physical process which can be described by computation but it nevertheless could be so one of the interesting models the you've proposed as the orchestrated objective reduction yeah that's going from there you say so I say I have no idea so I wrote this book through my scientific career I thought you know when I'm retired I have enough time to write a sort of a popular book which I will explain my ideas and puzzles but I like beautiful things about physics and mathematics and this puzzle about computability and consciousness and so on and in the process of writing this book well I thought I'd do it when I was retired I didn't actually I would didn't wait that long because there was a radio discussion between edward fredkin and marvin minsky and they were talking about what computers could do and they were entering and entering a big room they imagined entering this big room with the other end of the room two computers were talking to each other and as you walk up to the computers they will have communicated to each other more ideas concepts things than the entire human race had ever commute so I thought well know where you're coming from but I just don't believe you there's something missing that's it's not that so I thought well I should write my book and so I did it was roughly the same time Stephen Hawking this writing his brief history of time and Hades at some point the book you're talking about the emperor's new mind that's right and both are and incredible books the brief history of time and I'm person you mind yes it was quite interesting because he got he told me he'd got some Carl Sagan I think to write that forward good gosh what am I gonna do I'm not gonna get anywhere unless I get somebody so I know I know Martin Gardner so I wonder if he'd do it so he did and it is a very nice forward so that so that's an incredible book and some of the the same people you mentioned Ed Franken which I guess of expert systems Fame and Minsky of course people know in the eye world but they represent the artificial intelligence that do hope and dream that intelligences am i thinking well you know I see where they're coming from and they're like from exercise rectus oh yeah you're right but that's not my perspective so I thought I had to say it and as I was writing my book you see I thought well I don't really know anything about neurophysiology what am i doing writing this book so I certainly reading up about neurophysiology and I rate I'm nothing I'm trying to find out well how it is the nerve signals could possibly preserve quantum coherence and all I read is that the second electrical signals which go along the nerves create some effects through the brain there's no chance you can isolate it so this is hopeless so I come to the end of the book and I'm more or less give up and just think of something which I didn't believe in this maybe this is the way around it but no and then you say I thought well maybe this book well at least stimulate young people to do science or something and I got all these letters from old people instead he's the only people who could had time to read my book so I mean except for Stuart Hameroff except for Stuart Hameroff you don't have a rough road to me and he said I think you're missing something you don't know about microtubules do you didn't put it quite like that but that was more or less it and he said this is what you really need to consider so I thought oh my god yes that's a much more promising structure so I mean fundamentally you were searching for the source of a non computable source of consciousness within the human brain yeah in the biology and so what are mark if I may ask what are microtubules well you see I I was ignorant in what address I never came across them and in in in the books I looked at that's I only read rather superficially which is true but I didn't know about microtubules Stuart I think one of the things here was impressed him about them is when you see pictures of mitosis that's a cell dividing and you see all the chromosomes and the chromosomes get their gate or gate line and then they get pulled apart and so that as the cell divides the half the chromosomes go you know how their web is divided into the two pass and they go to different ways and what is it that's pulling them apart well those are these little things called microtubules and so he starts to get interested in them and he formed the view well he was his day job or night job of where every call it is to put people to sleep except he doesn't like calling asleep because it's different general anesthetics in a reversible way so you want to make sure that they don't experience the pain that would otherwise be something that they feel and consciousness is turned off for a while and it can be turned back on again so it's crucial that you can turn it off and turn it on and what do you do when you're doing that what do general anesthetic gases do and see he formed the view that it's the microtubules that they affect and the details of why he formed that view is not wasn't clear to me but there but there's an interesting story he keeps talking about but I've found this very exciting because I thought these structures these little tubes which inhabit pretty well ourselves it's not just neurons apart from red blood cell red blood cells they inhabit pretty well all the other cells in the body but they're not all the same kind you get different kinds of microtubules and the ones that excited me the most and this is may still not be totally clear but they're ones that excited me most were the ones that the only ones that I knew but at the time because they were there very very symmetrical structures and I had reason to believe that these very symmetrical structures would be much better at preserving a quantum state quantum coherence preserving the thing without you just need to cut preserve certain degrees of freedom without them leaking into the environment once they leak into the environment your loss so you ought to preserve these quantum states at a level which the state reduction process comes in and that's where I think the non computability comes in and it's the measure process in quantum mechanics what's going on so something about the the measurement process what's going on something about the structure on the microtubules yes your intuition says maybe there's something here maybe this kind of structure allows for the the mystery the there was a moment of chance yes it just struck me that partly it was the symmetry because there is a feature of symmetry you can predict preserve quantum coherence much better with symmetrical structures there's a good reason for that and that impressed me a lot I didn't know the difference between the a lattice and B lattice at that time which could be important now that could in medicine this year which isn't talked about much but that's some in some sense details we could take a step back just to say these people are not familiar so this this this was called the orchestrated objective reduction idea or orko R which is a biological philosophy of mind the postulates that consciousness originates at the quantum level inside neuron so that has to do with your search for where where is it coming from so that's counter to the notion that consciousness may arise from the computation performed by the synapses yes the key point here sometimes people say it's because it's quantum mechanical it's not just that see it's it's it more outrageous than that you see this is one reason I think we're so far off from it because we don't even know the physics right you see it's not just quantum mechanics people say oh you know quantum systems and biological structures no well he's starting to see that some basic biological systems does depend on quantum I mean look you the first place all of chemistry is quantum mechanics people got used to that so they don't count that so you said let's not count come on chemistry we sort of got the hang of that I think but you have quantum effects which are not just chemical in photosynthesis and this is one of the striking things in the last several years that photosynthesis seems to be a basically quantum process which is not simply create chemical it's using quantum mechanics in a very basic way so you can start saying oh well with photosynthesis is based on quantum mechanics why not behave you have neurons and things like that maybe there's something which is a bit like photosynthesis in that respect but what I'm saying is even more outrageous than that because those things are talking about conventional quantum mechanics now my argument says that conventional quantum mechanics if you're just following the Schrodinger equation that's still competing well so you've got to go beyond that so you've got to go to where quantum mechanics goes wrong in a certain sense you have to a little bit careful about that because the way people do quantum mechanics is a sort of mixture of two different processes one of them is the Schrodinger equation which is a an equation my Schrodinger wrote down and it tells you how the system the state of a system evolves it evolves according to this equation completely deterministic but it involves in two ridiculous situations and this was much frightening it was very much pointing out with his cat he said you follow my equation that's Schrodinger's equation and you could say that you have two cat a cat which is dead and alive at the same time that would be the evolution of the Schrodinger equation would lead to a state which is the cat being dead and alive at the same time and he's more or less saying this is an absurdity people nod I say oh well Schrodinger said you couldn't have a cat with deadly it's not that you see he was saying this is an absurdity there's something missing and that the reduction of the state or the collapse of the wavefunction or whatever it is is something which is has to be understood it's not following the Schrodinger equation it's not the way we conventionally do quantum mechanics there's something more than that and it's easy to quote Authority here because Einstein at least three of the greatest physicists of 20th century who were very fundamental in developing quantum mechanics Einstein one of them Schrodinger another Dirac another you have to look carefully it directs writing because he didn't tend to say this out loud too much because he was very cautious about what he said you find the right place and you cease he says quantum mechanics is a provisional theory we need something which explains the collapse of a wavefunction we need to go beyond the theory we have now I happen to be one of the kinds of people there are many there is a whole group of people they're all considered to be a bit you know bit Mavericks who believe that quantum mechanics needs to be modified there's a small minority of those people which were really a minority who think that the way in which it's modified has to be with gravity and there is an even smaller minority of those people who think it's a particular way that I think it is you see so so those are the quantum gravity folks for what's well you see quantum gravity is already not this because when you say quantum gravity what you really mean is quantum mechanics and Clyde - gravitational Theory so you say let's take this wonderful formalism of quantum mechanics and make gravity fit into it so that is what quantum gravity is meant to be now I'm saying you've got to be more even-handed that gravity affects the structure of quantum mechanics - it's not just you quantize gravity you've got to gravity as quantum mechanics and it's it's a two-way thing but then when you even get started so that you're saying and we have to figure out totally new ideas indirectly no yes it's you were stuck I don't have a theory that's the trouble so this is a big problem if you say okay well what so there I don't know so we may be in the very early days sort of it is in the very early days and there but just making this point yes you see Stuart Hameroff to be open Rose says that it's got to be a reduction of the state and so so let's use it the trouble is Penrose doesn't say that Penrose says well I think that no no we have no experiments as yet which shows that yes there are experiments which are being thought through and which I'm hoping will be performed there is an experiment which is being developed by dirt Romney Stowe who is I've known for a long time who shares his time between Leiden in the Netherlands and Santa Barbara in the US and he's been working on an experiment which could perhaps demonstrate that quantum mechanics as we now understand it if you don't bring in the gravitational effects it has to be modified and and then there's also experiments that are underway that kind of look at the microtubule side of things to see if there's in the biology you could see something like that could you briefly mention it because that's a really sort of one of the only experimental attempts in the very early days of even yeah about I think there's there's a very serious area here which is what Stuart Hameroff is doing and I think it's very important one of the few places that you can really get a bit of a handle on what consciousness is is what turns it off and when you're thinking about general anesthetics it's very specific these things turn consciousness off what the hell do they do well Stuart and a number of people who work with him and others happen to believe that the general anesthetics directly effect microtubules and there is some evidence for this I don't know how strong it is and how watertight the cases but I think there is some evidence pointing in that kind of direction it's not just an ordinary chemical process there's something quite different about it and one of the main candidates is that these anesthetic gases do affect directly microtubules and how strong that evidence is I wouldn't position to say but I think there is fairly impressive evidence and the point is the experiments are being undertaken with yes I mean that is experimental it's a very clear direction where you can think of experiments which could indicate whether or not it's really microtubules which the anaesthetic gas is directly affect that's really exciting one of the sad things is as far as I'm for my outside perspective it's not many people are working on this so there's a very like Oh Stewart even it feels like there's very few people are carrying the flag forward on this I think it's it's not many in the sense it's a minority but it's not zero anymore you see when I were originally serious you know we were just just us and a few few of our friends they weren't many people think it but it's grown into into it one of the main viewpoints yeah there might be about four or five or six different news that which people hold and it's one of them so it's it's considered as one of the possible lines of thinking yes you describe physics theories as falling into one of three categories the superb the useful or the tentative I like those words it's a beautiful categorization do you think we'll ever have a superb theory of intelligence and of consciousness we might we're a long way from it I don't think we're even whether in the tentative scale I mean it's uh you don't think we've even entered the realm of tentative probably no I think yeah that's raised you know what do you see the circle is so controversial we don't have a clear view which which is accepted by a majority I mean you say yeah people most views are computational in one form or another they think it's some but it's not very clear because even the the IIT people who I think think of them as computational but I've heard them saying they know consciousness is supposed to be not computation I say well if it's not coming in what the hell is it what's good what's going on but physical processes are going on which that what does it mean for something to be computational then so is uh well there has to be a process which is it's very curious the way the history has developed in quantum mechanics because very early on people thought there was something to do with consciousness but it was almost the other way around you see you have to say the Schrodinger equations says all these different alternatives happen all at once and then when is it that only one of them happens where one of the views which was quite commonly held by a few distinguished quantum physicists this well a conscious being looks at the system what becomes aware of it and at that point it becomes one of the other that's a row where consciousness is somehow actively reducing the state my view is almost the exact opposite of that it's the state reduces itself in some way which some non computational way which we don't understand we don't have a proper theory of and that is the building block of what consciousness is so consciousness is the other way around it depends on that choice which nature makes all the time when the state becomes one of the other rather than the superposition of one and the other and when that happens there is what we're saying now an element of proto consciousness takes place proto consciousness is roughly speaking the building block out of which actual consciousness is constructed so you have these proto conscious elements which are when the state decides to won't do one thing or the other and that's the thing which when organized together that's the oh our part in orko our but the ork part that's the the Oh our part at least once can see where when driving as a theory you can say it's the quantum choice of going this way or that way but the ork part which is the orchestration of this is much more mysterious and how does the brain somehow orchestrate all these individual our processes into a genuine genuine genuine just experience and it might be something that's beautifully simple aware and completely in the dark about yeah I think at the moment it's best the thing you know we happily put the word walk down there to say orchestrated that's even more unclear what that really means just like the word material orchestrated yeah it's we know yes and we've been dancing a little bit between the word intelligence or understanding in consciousness do you kind of see those as sitting in the same space of mystery yes you see I tend to say you have understanding and intelligence and awareness and somehow understanding is in the middle of it you see it's I like to say could you say of an entity that is actually intelligent if it doesn't have the quality of understanding nice I'm using terms I don't even know how to define but who cares really there's somewhat poetic so I I somehow understand them yes I think there's not mathematical in nature yes you see as a mathematician I don't know how to define any of them but at least I can point to the connections so the idea is intelligence is something which I believe needs understanding otherwise you wouldn't say for any intelligence an understanding needs awareness otherwise you wouldn't really say it's understanding you say of an entity they understand something and it's unless it's really aware of it in our normal usage so there's a three sort of weirdness understanding and intelligence and I just tend to concentrate on understanding because that's where I can say something okay that's the kernel theorem and things like that but they what does it mean to be perceive the color blue or something I mean I guess it's much more difficult question I mean is it the same if I see a color blue and you see it if you're something with them wasn't this this condition wants to call them or were you assign a sound - yeah yeah that's right you get colors and sounds mixed up and that sort of thing I mean an interesting subject um here but from the physics perspective from the fundamentals perspective we don't I think we're way off pretty much understanding what's going on there in your 2010 book cycles of time you suggest that another universe may have existed before the Big Bang can you describe this idea first of all what is the Big Bang sounds like a funny word and what may have been there before it yes just as a matter of terminology I don't like to call it another universe because when you have another universe you think of it kind of quite separate from us but these things they're not separate now the Big Bang conventional theories yeah I was actually brought up in the sense of when I started getting dressed in cosmology there was a thing called the steady-state model which was sort of philosophically very interesting and there wasn't a big bang in that theory that somehow new material was created all the time in the form of hydrogen and the universe kept on expanding expanding expanding and there was room for more hydrogen it was a rather philosophically nice picture it was disproved when the Big Bang well when I say the Big Bang this was theoretically discovered by people trying to solve Einstein's equations and apply it to cosmology Einstein didn't like the idea he liked and I a universe which was there all the time and he had a model which they wish there all the time but then there was this discovery accidental discovery a very important discovery of this microwave background and if you you know there's the crackle on your television screen which is is already sensing this microwave background which is coming at us from all directions and you can trace it back and back and back and back and it came from a very early stage of the universe well it's part of the Big Bang Theory the Big Bang Theory was when people tried to solve our science equations they really found you have to have this initial State the universe it was used to be calmly primordial Assam and things like this there's freedmen and a la Mettrie Freedman was a Russian the Metro was the Belgian and they independently were basically Friedman first the maitre talked about the initial state which is a very very concentrated initial state which seemed to be the origin of the universe from more Deol Adam that's the primordial atom is what he called it yes full term and then it became well Fred Hoyle used the term Big Bang in a kind of derogatory sense just like it was a Schrodinger in the cat's right yeah it's this like sort of geek tick got picked up on whereas it wasn't his intention originally but did then the evidence piled up and piled up and my one of my friends and I learned a lot from him when I was in Cambridge just any Xiaomei usually a proponent of steady state and then he got to convert it just said no I'm sorry I had a great respect for him he went around lecturing said I was wrong the steady-state model doesn't work there was this big bang and this microwave background that you see okay it's not actually quite the Big Bang when I said not quiet it's about 380,000 years after the Big Bang but that's what you see but then you have to have had this Big Bang before it's in order to make the equations work and it works beautifully except for one little thing which is this thing called inflation which people had to put into it to make it work when I first heard of it I didn't like it at all what's inflation inflation is it in the first I'm gonna give you a very tiny number think of a second that's not very long now I'm going to give you a fraction of a second one over a number this number has 32 digits between well it's it between 36 and 32 digits tiny tiny time between those two tiny ridiculous seconds fraction of a second the universe was supposed to have expanded in this exponential way an enormous way for no Patera parent reason you had to invent a particular thing called the in photon field to make it do it and I thought this is completely crazy there are reasons why people stuck with this idea you see the thing is that I formed my model for reasons which are very fundamental if you like it has to do this very fundamental principle which is known as the second law of thermodynamics the second law of thermodynamics says more or less things get more and more random as time goes on now another way of saying exactly the same thing is things get less and less random as things go back if you go back in time they get less and less random let me go back and back and back and back and the earliest thing you can directly see is this microwave background what's one of the most striking features of it is that it's random it has this what you call this spectrum of which is what's called the Planck spectrum of frequencies different intensities for different frequencies and it's this wonderful curve due to Max Planck and what's there telling you it's telling you that the entropy is a maximum start is often maximum and it's going up over since I call that a mammoth in the room paradox and mother yes it is so people why don't cosmologists worry about this so I'm worried about it and then I thought well it's not really a paradox because you're looking at matter and radiation at a maximum entropy state what you're not seeing directly in that is the gravitation its gravitation which is not thermalized the gravitation was very very low entropy and it's low entropy by the uniformity and you see that in the microwave - it's very uniform over the whole sky I'm compressing a long story into a very short sentence and doing a great job yet so what I'm saying is that there's a huge puzzle why it was gravity in this very low entropy state very high organized state everything else was all random and that to me was the biggest problem in cosmology the biggest problem nobody seemed worried about it people say they solved all the problems and they don't even worry about it they think inflation sources it doesn't I can't because it's it's just just to clarify that was your problem with the inflation describing some ass but those yes moments right after the Big Bang inflation we're supposed to stretch it out make it all uniform you see it doesn't do it because you can only do it if it's uniform already at the beginning it's it's you just have a look I can't go into the details but it doesn't solve this and it was completely clear to me it doesn't solve well word is the conformal cyclic cosmology of yeah we're starting to talk about something before yes that's singular I began I was just thinking of myself how boring this universe is going to be you've got this exponential expansion this was discovered early in the in this century 20th 21st century people discovered that these supernovae exploding stars showed that the universe is actually undergoing this exponential expansion so it's a self-similar expansion and it seems to be a feature of this term that Einstein introduced into his cosmology for the wrong reason he wanted a universe that was static he put this new term into his cosmology and to make it make sense it's called the cosmological constant and then when he got convinced that the universe had the Big Bang he retracted it complaining this was his greatest blunder the trouble is it wasn't a blunder it was actually right very ironic and so the universe seems to be behaving with this cosmological constant okay so this universe is expanding and expanding what's going to happen in the future well it gets more and more boring from well what's the most interesting thing in the universe well there's black holes the black holes more or less gulped down the entire clusters of galaxies the class it'll swallow up most of our galaxy we will run into Andromeda galaxies black hole that black hole will swallow em they will get bigger and bigger and they'll basically swallow up the whole cluster of galaxies golf it all down pretty well all most of it maybe not all most of it okay that'll happen too there'll be just these black holes around pretty boring but still not as boring as it's going to get it's going to get more boring because these black holes you wait you wait and you wait and you wait and wait and unbelievable length of time and Hawking's black hole evaporation starts to come in and the black holes you just it's a clarity Deus finally evaporate away each one goes away it disappears with the pop at the end what could be more boring that it was boring then now this is really boring there's nothing not even black holes universe gets colder and colder and colder and colder and ever this is very very boring now that's not science is it but it's it's emotional so I thought who's going to be bored by this universe not us we won't be around it'll be mostly photons running around and what the photons do they don't get bored because it's a part of relativity you see it's not really that they don't experience anything that's not the point the photons get right out to infinity without experience anytime it's the way for them where your relativity works and this was part of what I used to do in my old days when I was looking gravitational radiation and how things behaved infinity infinity is just like another place you can squash it down as long as you don't have any mass in the world infinity is just another place the photons get there the gravitons get there what do they get they've run to infinity they say well now I'm here what way there's something on the other side is there the usual view it's just a mathematical notion there's nothing on the other side that's just the boundary of it a nice example is this beautiful series of pictures by the Dutch artist MC Escher you may know them the ones called circle limits they're very famous one with the angels and the Devils and you can see them crowding and crowding and crowding up to the edge now the kind of geometry that these angels and devils and habits that's their infinity but from our perspective infinity is just a point is a place ok there it is I can you just take a brief pause yes and the in just the word you're saying infinity is just a place so I have for the most part infinity sort of even just going back yeah infinity is a mathematical concept I think this is what I think there's an actual physical manifestation in which way does infinity ever manifests itself in our physical universe what it does in various places you see it's the thing that we're if you're not a mathematician you think aren't finished yeah I can't think about that mathematicians think about affinity all the time they get used to the idea and they just play around with different kinds of infinities and it becomes no problem but yeah you just have to take my word for it now one of the things is you see you have taken Euclidian geometry well it just keeps on keeps on keeps on going and it goes out to infinity now there are other kinds of geometry and this is a what's called hyperbolic geometry it's a bit like Euclidean geometry so it'll be different it's like what Asia was trying to describe in his angels and devils and he learned about this from coxeter and he think that's a very nice thing I try to represent this infinity to this kind of geometry so it's not quite Euclidean John which is a bit like it that the angels and the Devils inhabit and their infinity mind this nice transformation you squash the other infinity down so you can draw it as this nice circle boundary to their universe now from our outside perspective we can see their infinity as this boundary now what I'm saying is that it's very like that the infinity that we might experience like the angels and devils in their world can be thought of as a boundary now I found this a very useful way of talking about radiation gravitational radiation and things like that it was a trick mathematical trick so no what I'm saying is that that mathematical trick becomes real that somehow the photons they need to go somewhere because for their from their perspective infinity it's just another place now this is a difficult idea to get your mind around so that's why Kozma one of the reasons because mom's just are finding a lot of trouble taking me seriously but to me it's not not such a wild idea what's on the other side of that infinity you have to think why am I allowed to think of this because photons don't have any mass and we in physics have beautiful ways of measuring time there are incredibly precise clocks atomic and nuclear clocks unbelievably precise while they be so precise because of the two most famous equations of 20th century physics one of them is Einsteins e equals mc-squared what's that tell us energy and mass are equivalent the other one is even older than that still 20th century only just Max Planck e equals H nu nu is a frequency H is a constant again Lexie E is energy energy and frequency are equivalent put the two together energy and mass equivalent Einstein and in frequency equivalent Max Planck put the D together mass and frequency are equivalent absolutely basic physical principle if you have a massive entity a massive particle it is a clock with a very very precise frequency it's not you can't directly use it you have to scale it down so your atomic and nuclear clocks but that's the basic principle you scale it down to something you can actually perceive but it's the same principle if you have mass you have beautiful clocks but the other side of that coin is if you don't have mass you don't have clocks if you don't have clocks you don't have rulers you don't have scale so you don't have space and time you don't have a measure of the scale of space and all scale you have if that you do have the structure that what's called the conformal structure you see it's what the angels levels have if you look at the eye of the devil no matter how close to the boundary it is it has the same shape but it has a different size so you can scale up and you can scale down but you mustn't change the shape so it's basically the same idea but applied to space-time now in the very remote future you have things which don't measure the scale but the shape if you like is still there now that's in the remote future now I'm going to do the exact opposite now I'm going to go way back into the Big Bang now as you get there things go hotter and hotter denser and denser what the universe dominated by particles moving around almost with the speed of light when they get almost with the speed of light okay they begin to lose the mass to therefore a completely opposite reason they lose the sense of scale as well so my crazy idea is the Big Bang and a remote future they seem completely different one is extremely dense extremely hot the other is very very rarefied and very very cold but if you squash one down by this conformal scale and you get the other so although they look and feel very different they're really almost the same the remote future on the other side and claiming is that one of the photons go they go into the next Big Bang you've got to get your mind around that crazy idea taking a step on the other side of the place that is infinity yes but I'm saying the other side of our Big Bang now I'm going back into the Big Bang that was the remote future of a previously on previously on and what I'm saying is that previously on there are signals coming through to us which we can see and which we do see and these are both signals the two main signals are to do with black holes one of them is the collisions between black holes and as they spiral into each other they release a lot of energy in the form of gravitational waves those gravitational waves get through in a certain form into the next DM that's fascinating that there's some I mean maybe I'm maybe you can correct me if I'm wrong but that means that some information can travel yes from another eon exactly that that is fascinating I mean I've seen somewhere described sort of the discussion of the Fermi paradox you know that if there's intelligent life yes being you know communication me immediately takes you there so we have a paper I have my my colleague waha Gossage on who I work with this on these ideas for a while we have a crazy paper on that yes so the family paradoxes right so so if the universe is just cycling over and over and over punctuated by have the punctuated the singularity of the Big Bang and then intelligent or any kind of intelligent systems can communicate through from e on T on why haven't we heard anything from our alien friends because we don't know how to look that's fundamentally the reason is we I don't know you see it's it's speculation I mean the SETI program was a reasonable thing to do but still speculation it's trying to say ok maybe not too far away with a civilization which got there first before us early enough that they could send our signals but how far away would you need to go before I mean I don't know we with so little knowledge about that we haven't seen any signals yet but it's worth looking it's worth looking and what I'm trying to say here's another possible place we might look now you're not looking at civilizations which got there first you're looking at those civilizations which were so successful probably a lot more successful more likely to be man looks of things which knew how to handle their own global warming or whatever it is and to get through it all and to live to a ripe old age in the sense of a civilization to the extent that they could harness signals that they could propagate through for some reason of their own desires whatever we wouldn't know to to other civilizations which might be able to pick up the signals but what kind of signals would they be I have a foggiest let me ask the question yes what to you is the most beautiful idea in physics or mathematics or the art at the intersection of the two I'm going to have to say complex analysis I might have said infinities and one of the most single most beautiful idea I think was the fact that you can even infinities of different sizes and so on but that's anyway I think complex analysis this goes it's got so much magic in it it's a very simple idea you take these you guys hope you do you take numbers you take the integers and then you fill them up into the fractions and the real numbers you imagine you're trying to measure a continuous line and then you think of how you can solve equations then what about x squared equals minus 1 well there's no real number which has to satisfies that so you have to think of well there's a number called I you think you invent it well in a certain sense it's there already but this number when you add that square root of minus 1 to it you have what's called the complex numbers and they're an incredible system if you like you put one little thing in you put square root of -1 in and you get how much benefit out of it all sorts of things that you'd never imagined before and it's that amazing or hiding there in putting that square root of -1 in so in the sense that's the most magical thing I've seen in mathematics or physics and it's in quantum mechanics and in quantum mechanics for there already you might think what's it doing there ok just a nice beautiful piece of mathematics and then suddenly we say nope it's the very crucial basis of quantum mechanics so on there and the way the world works so on the question of whether math is discovered or invented it sounds like you may be suggesting that partially as possible the math is indeed discovered oh absolutely yes no it's more like archeology than you might think so let me ask the most ridiculous maybe the most important question what is the meaning of life what gives your life fulfillment purpose happiness and meaning why do you think we're here on this given all the Big Bang and the infinities of photons that we've told I would say I think it's not a stupid question I mean there are some people you know many of my colleagues new scientists they say well that's a stupid question meaning yeah well we just hear because things came together and produce life and so what I think there's more to it but what there is that's more to it really much idea it might be somehow connected to the mechanisms of consciousness though we're talking about the mystery there it's connected with all sortsa yeah I think these things are tied up in ways which er you see I tend to think the mystery of consciousness is tied up with the mystery of quantum mechanics and how it fits in with the classical world and that's all to do with the mystery of quantum of complex numbers and there are mysteries there which I look like mathematical mysteries but they seem to have a bearing on the way the physical world operates we're scratching the surface we have a long huge way to go before we really understand that and it's a beautiful idea that the the the depth the mathematical depth could be discovered and then there's tragedies of Gaydos and completeness along the way they will have to somehow figure our ways around yeah so Roger as a huge honour to talk to you thank you so much for your time today everything my pleasure thank you thanks for listening to this conversation with roger penrose and thank you to a presenting sponsor at Cash app please consider supporting this podcast by getting expressvpn and expressvpn comm / flex pod and downloading cash app and using collects podcast if you enjoy this podcast subscribe I need to review it with five stars and napa podcasts supported on patreon or simply connect with me on Twitter at lex friedman and now let me leave you with some words of wisdom that roger penrose wrote in his book the emperor's new mind beneath all this technicality is the feeling that it is indeed quote unquote obvious that the conscious mind cannot work like a computer even though much of what is involved in mental activity might do so this is the kind of obvious that a child can see though the child may later in life become browbeaten into believing that the obvious problems are quote unquote non problems to be argued into non-existence by careful reasoning and clever choices of definition children sometimes see things clearly that are obscured in later life we often forget the wonder that we felt as children on the cares of the quote unquote real world have begun to settle on our shoulders children are not afraid to post basic questions that might embarrass us as adults to ask what happens to each of our streams of consciousness after who died where was it before we were born might we become or have been someone else why do we perceive at all why are we here why is there a universe here at all in which we can actually be these are puzzles that tend to come with the awakenings of awareness in any of us and no doubt will the awakening of self-awareness within which ever creature or other entity first came thank you for listening and hope to see you next time you