Joe Rogan - Mathematician on Trying to Measure Consciousness

I am a big fan of your work. I have read much of your work. I've seen many of your interviews and videos online. And one of the things that I really wanted to talk to you about that I find quite interesting is consciousness and your belief that consciousness is not simply calculation, but that there's something more to it. And what what you think this more could possibly be from a scientific perspective, which is unusual, because a lot of people have some theories about consciousness, but they're usually crazy people like myself. Well, I mean, we're all conscious. And so we may have theories about it. Yeah. But no, the ideas came by somewhat roundabout route. I went to Cambridge to graduate work. It was mathematics. I was working on pure mathematical subject, algebraic geometry. But I thought, you know, we got three years, I'll spend some of the time going to other talks that might be interesting. So I went to three talks, particularly, which had a big influence on me. One was a talk by Herman Bondi was a general relativity cosmology. Wonderful talk with very sort of animated presentation he had. And then there was a talk by Paul Dirac, one of the founders of quantum mechanics. And his talk, well, his complete wonderful talk to wonderful lectures as well, but in a completely different style, he was very quiet and precise in what he said and everything. Anyway, the very first lecture, he was talking about the superposition principle in quantum mechanics. So if you have a particle, and it could be in one spot, or it could be in another spot, then you have all sorts of states where it can be in both places at once. And that's sort of strange, but you've got to get used to that idea. And he illustrated with his piece of chalk, and I think he broke it in two, to illustrate it could be in one spot or in the other. And my mind sort of wandered at that point, I don't know what I was thinking about, but I wasn't concentrating. And a few minutes later, he finished his description, his explanation. And I had some vague memory of something about energy, but I didn't understand what he said. And I've been totally mystified by this ever since. So I suppose if I'd heard what he said, he would have said something to calm me down and sort of accept it in one way or another. But as it was, it seemed to me this was a major issue. How on earth do you have things that don't behave according to what quantum mechanics says, like cricket balls and baseballs and things like that. Anyway, that's two of the talks. The other course was a course by a man called Steen who talked on mathematical logic. And he explained things like Goedel's theorem and Turing machines, Turing machines being the mathematical notion upon which modern computers are based or computers basically. And the thing about Goedel's theorem, you see, I heard I used to have a colleague when I was at undergraduate in Percival who also became a scientist later on. And we talked about logic and you know how you could make these kinds of mathematical systems, which worked out logic. And I'd heard about this Goedel's theorem, which seemed to say that there were things in mathematics that you just couldn't prove. And I didn't like that idea. But when I heard the when I went to this course by Steen and he explained what it really says and what it says, I suppose you've got a method of proving things in mathematics. And when I say things, I mean things with numbers. The one famous example is Fairmont's last theorem. There's the Goldbach conjecture, which isn't yet proved that every even number bigger than two is the sum of two prime numbers. That's the sort of example of the thing. It's just sort of mathematical things about numbers, which you can see what they mean. But it may be very difficult to see whether it's true or untrue. But the idea often is in mathematics, you've got a system of methods of proof. And the key thing about these methods of proof is that you can have a computer check whether you've done it right. So you these rules, you know, they could be adding a and b, it's the same as b and a and things like that. And you if you give your you say to the computer, say, here's a theorem like Goldbach conjecture, and you see whether it can be proved. And you say, maybe I got a proof, and this follows these steps. And you give it to the computer and it says, yep, you've done it right. It's true. Or maybe we say you've done it right. And it's not true. Or it may not say anything, much as it go on forever. But these are the sort of outcomes. And the point about it is that if you believe that these procedures do give you a proof, in other words, that if the algorithm says, yeah, it's true, then you believe that it is true. Because you've understood all the rules, you looked at the first one, say, yeah, that's okay. You did the second one said, oh, yeah, I see. Okay, that's great. And you go all the way down. And as long as you're convinced, all those rules work. And if it says yes, that's something you believe. Okay. Now, what Girdle shows is he constructs a very specific sentence, a statement, which is a number thing, like the Fair Muslaw's Theorem or something, the thing about numbers, which what he shows is if you trust this algorithm for proving mathematical things, then you can see by the way it's constructed that it's true. But you can also see by the way it's constructed, that it cannot be proved by this procedure. Now, this was amazing to me, because it tells me that, okay, you cannot formalize your understanding in a scheme which you could put on a computer. You see this statement, which Girdle comes up with is something you can see on the basis of the same understanding that allows you to trust the rules, that it's true, but that it's not actually derivable by the rules. You see it's true by virtue of your belief in the rules. And this to me was amazing. And I thought, golly, you know, what's understanding? What does it mean? Is it something following rules? Is it an algorithm? Well, this more or less says it's not an algorithm, because whatever it was, there will be something that you could still see is true, even though you don't get it through the algorithm that you had in the first place. So this was a, oh, there are a lot of subtleties about this too, which people argue about endlessly, but it was pretty convincing to me that this shows that we don't think when we understand something, that what's going on in our heads is not an algorithm. It's not following rules. It's something else. It's something that requires our conscious appreciation of what we're thinking about. I'm thinking is a conscious thing and understanding is a conscious activity. So I formed the view that conscious activities, whatever they are, not just that kind of thing, but, you know, playing music or falling in love or whatever these things might be, are not computations. There's something else going on. And then I thought, because I, you know, I like to think myself as a scientist, and I think that what's going in on our heads is according to the laws of physics, and these laws of physics are pretty good. They seem to work well in the outside world. And so I believe that the laws that work in our heads are the same as those laws. So I began to think about it well. What about Newton's mechanics? Well, you could put that on a computer. What about Einstein's special relativity? You could do that. What about Maxwell's wonderful equations, which tell you how electricity and magnetism operate, and light and radio waves and all these things. That's all follows this beautiful set of equations that Maxwell produced. You can put that on a computer. Okay, you may have to worry about approximations, and these depend on continuous numbers rather than discrete things. But I didn't think that's the answer. Then I thought, what about general relativity? Einstein's theory of gravity with curved space and all that. We're familiar now with LIGO, this detector, which is detected black holes spiraling into each other from distant galaxy. And how do we know that those signals are black holes? Well, because of calculations, people have put this thing on an algorithm, and you know what those signals look like. So Einstein's general relativity, sure, you can put that on a computer. What about quantum mechanics? Well, there's the famous equation of Schrodinger, which tells you how quantum state evolves. You could put that on a computer too. It's difficult in many ways, there's many more parameters you have to worry about, but it's just as computable as these other things. Well, you see, I then remember Dirac's lecture, you see, and how it is that these things that work in the quantum world don't seem to work at the level of classical big things. And it all depends on this process of what's called measurement in quantum mechanics. And the measurement process is something you learn how to do, but it's not the Schrodinger equation, it's something else. And Schrodinger himself was very intrigued by this fact that his own equation gives you nonsense. And the famous Schrodinger's cat, where he produces a situation in which the cat would be dead and alive at the same time, he produced that example simply to demonstrate that, roughly speaking, his equation gives you nonsense under these circumstances. So there's something else, and there's something else goes beyond our current quantum mechanics. And it tells you what happens when the quantum state makes a decision between what doesn't follow the Schrodinger equation, one thing or the other. Now, everybody knows that who does quantum mechanics, but they think, oh, it's what's called making a measurement, and you're allowed to do something different. But that didn't make sense to me. And so I had the view that, okay, there is a big gap in our understanding. And if there's something in the world, which isn't something you could put on a computer, that's where it is. So the view I've held that for a long time, and that there's something non-computable, something beyond computation involved in our understandings of things. So that's a view I held for ages. I didn't do much with it. I just held the view. Until I think there was a radio talk between Marvin Minsky and Edward Fredkin, and they were explaining about what computers can do. And they were talking about, okay, you have a computer, two computers talking to each other over there, and you walk up to the room. And the time you've walked up the room to the computers, they have communicated with each other more thoughts than the human race ever has done, you see. And I thought, well, I see where you're coming from, but I don't think that's what's happening. And human communication, human understanding is something different from what computers do. And consciousness is the key thing. Consciousness is something different from computation. So I've held that view. But then when I heard this talk by Minsky and Fredkin, I thought, well, I had ideas of writing a book sometime in a long time in the future when I'm retired. This was some while back, I say. And I thought, well, this gives you the focus. And so I wrote this book called The Emperor's New Mind, which is supposed to be saying, well, everybody seems to be thinking one thing, but the little kid notices that the Emperor doesn't have any clothes. So it was the theme of that story, which was the basis of the book. So I say, okay, maybe lots of people think that all we're doing is computing. But if you stand back and you say, well, no, there's something else going on. So that was the basis of my thoughts about consciousness. But I wrote this book thinking that by the time I got to the end of the book, you see, it was mostly about physics and mathematics and things like that. But I was really aiming for this thing about what's going on in conscious thinking. And I thought, well, I'll learn a bit about neurophysiology and so on. And by the time I get to the end of the book, I'll know pretty well what it could be. I didn't. I got to the end of the book. And I just sort of tapered off rather with something a little bit unbelievable. And that was the end. Now, you see, I hoped that this book would stimulate young people to get interested in science and that sort of thing, that mathematics. And that was fine. And when the book was published, I didn't get letters from young kids. I got letters from old retired people who the ones who'd had the time to read my book. Okay, well, that was a little disappointing, but okay, I'm glad the old retired people liked my book. But the other thing was I got a letter from Stuart Hammeroff. And this letter said, more or less, I think you don't appreciate that there's something else going on, not neurons. I mean, the neurons I could see, you couldn't isolate the quantum effects and you get the what's called environmental decoherence would happen and you get no way of keeping the quantum state to the level that you need in this picture. So I really didn't have it. But Stuart Hammeroff pointed out to me these little things called microtubules. And he'd built up a theory that microtubules were absolutely fundamental to consciousness. He had his own reasons for believing that. I'd never heard of them at that time. But then I checked up, you know, I get lots of letters from people who maybe don't make sense sometimes the letters. And this one, I thought, well, this is another one. I realized these microtubules are there. And they look like just the kind of thing that could well be supporting the kind of level of quantum mechanics up to a level where you could expect the quantum state to sort of collapse. That's the terminology people use in quantum mechanics. And microtubules, they're inside brain neurons. They are indeed. And this is a recent discovery? No, we could be going on. They're actually in lots of cells, you see. People often complain, oh, they're in your liver too, not just your brain. So why isn't your liver conscious and all that? But this has to do with the organization of them and the nature of them, the particular kind of microtubules. How they're arranged, which is different in the brain. How does it vary in the brain compared to other cells? I think one big difference, although not Stuart emphasizes this so much, there are two kinds of microtubules. They're the ones called the A lattice and the B lattice. And the A lattice ones are the very symmetrical ones. They're tubes and they look the same all the way around. They've got a very beautiful arrangement of these proteins called tubulin. And they make a very nice arrangement, which is connected with Fibonacci numbers and things like that. So they look a bit like fur cones, but they're all parallel. They don't taper off. But the thing is in the brain, I think most microtubules are probably what are called B lattice ones. And they don't have so much symmetry. They've got a sort of seam down the one side. And they're very important in transporting substances around cells and so on. And microtubules, all sorts of things, they don't just do what Stuart and I think they may be doing in the brain. So the idea is that in the brain, they're organized differently. And probably the ones that are important are the A lattice ones, which are the very symmetrical ones. And for a long time, people couldn't see the difference because they look very similar. And they may well be the ones that happen to be in pyramidal cells as a particular kind of cell. So one of the things that interested me a lot is how it is that not all parts of the brain are the same in this respect. You see you've got the cerebrum, this is the part at the top and divided down the middle. And when you see brains, that's what you normally see with the convolutions in it. But right underneath and at the back, there's a thing called the cerebellum, which looks more like a ball of wool or something. And the cerebellum, I may still be argument about this, but it seems to be that it's completely unconscious. And it has comparable number of neurons, far more connections between neurons and the cerebrum. And it's what takes control and maybe when you're driving your car and you're thinking about something else, and you don't, you're not thinking what you're doing, because it's unconscious. And the unconscious control, you know, a pianist who's very expert and moves the fingers around and plays a note with a little finger, that pianist doesn't think, well, I got to move that muscle this way and this bone that way and so on. And it's, it's all controlled unconsciously. And a lot of this unconscious control is done somewhere else in the cerebellum when you when you get really skilled. So it seemed to me, okay, you've got different kinds of structures different. And it could well be that these pyramidal cells, which have a particular organization of microtubules are the ones that where the consciousness is really coming, coming to light mainly. I don't know, there's a lot which is which is not known about this controversial and all sorts of things. But the cerebellum seems to be different and organized differently. So it's not just how many neurons how many connections are there, because there are more in the cerebellum. So it's not that something else. Do they know this from observing the brain through fMRI or something like that during particular activities? I don't know. I would imagine partly just examining it went from dead people and looking at brains and trying to estimate how many neurons there are in it. Right. But how would they know what which part part which is conscious particular? I don't know that they do know that well, I guess. But the cerebellum, there is a bit of an argument about that. I thought whether it's completely unconscious or not, but it seems that actions that that are carried out by the cerebellum, you don't, you're not aware of what you're doing. But I mean, it's, you know, if you're the tennis player who has to think very carefully about whether we know what we tilt the ball, now, the control of what you're doing, so overall control is probably done with the cerebellum. But the cerebellum is controlling the detailed motions, how the fingers move and all that kind of thing. And then you make sure that if you the player thinks kind of hit the ball down, down the line there, and then the rest is done under the control of an unconscious procedure. I mean, I may be simplifying. But I understand what you're saying. So you're saying that there's, we don't totally understand, but we know that there's different parts of the brain that are responsible for different activities and some activities don't seem to be conscious. Yes, yes. I mean, I think it's probably the case, no, I'm maybe, I don't know, I shouldn't make a statement. I don't really know. But certainly, there are lots of different parts of the cerebrum, which maybe, which maybe not conscious too. So I'm not saying that the whole thing is capable of being conscious. It's they seem to be differences in different parts. But are you convinced that microtubules are responsible for consciousness or it's a primary theory? I think they're the one of the best candidates. I see, I don't think it's only microtubules. I don't know. I'm not sure what Stuart Hemmerff's view on this is. He certainly thinks the microtubules are exceedingly important in consciousness. And I think he's right. That's the feeling I get. And he's done a lot of work on trying to find what anesthetic gas is. It's an important, one of the important ways you can tell things about consciousness, most of it you can't, it's just here, say, and whatever it is. But one of the important ways you can tell something about consciousness is what turns it off in a reversible way. In Stuart's job is to, you know, he's an anesthesiologist, he puts people to sleep. Well, I think he would complain if I say putting it to sleep because anesthetic is actually different from sleep. But you make them unconscious in a reversible way, you want to make sure you can wake them up again. And it's obviously a very skilled thing. But I guess a lot of his colleagues might be skilled at doing it, but don't be asked the questions about what they're actually doing from the point of view of the biology and the physics and so on. So Stuart was really interested in that question. Partly, I think things like mitosis cell division. And he was very struck by the way that the chromosomes all line up and that this microtubules which pulling them, and they're really a big part in the structure of cells and how they behave and so on. But why their consciousness? Well, I guess it was experience with putting people under anesthetics. And the fact that the gases which put you to sleep and they're, again, I shouldn't say to sleep, but put you on anesthetic are very unconnected chemically, they're different kinds of things. But yet they still seem to have the same effect. And to understand what it is that they affect is, you know, that's a lot of his interest is to do with that. So just by putting someone unconscious and registering what parts of the brain are no longer active. This is what they're using to sort of reverse engineer by turning those parts on. That's what enables consciousness. Is this the well, I think it's probably simplification of what's going on. But that's, that's a good first first step. Yes.