Episode 100: Interview with David Deutsch

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Unofficial, reviewed transcript. It may still contain mistakes; check the podcast when wording matters.

Speakers are labeled by first name where identified. Unidentified-speaker labels may refer to different people. Bracketed question marks indicate uncertain wording.

Transcript

[00:00:19]  Unidentified speaker: Welcome to The Theory of Anything Podcast.

[00:00:23]  Peter: Today, for our 100th episode, we've got the man who needs no introduction, David Deutsch.

[00:00:34]  Unidentified speaker: How are you doing today, David?

[00:00:36]  Unidentified speaker: Fine, thank you.

[00:00:37]  David: Thanks for inviting me.

[00:00:39]  Peter: Yeah, I hope you don't mind if I call you David.

[00:00:41]  Unidentified speaker: Seems, no, seems right.

[00:00:43]  Peter: And of course, Bruce Nielson. How are you today, Bruce?

[00:00:46]  Unidentified speaker: Good.

[00:00:47]  Unidentified speaker: Excited.

[00:00:49]  Peter: Me too, to say the least.

[00:00:52]  Unidentified speaker: First, I'm going to give a short introduction here.

[00:00:55]  Peter: This will not be one of my 25-minute rambling introductions. I don't think our audience will be too disappointed with that. Bruce can say a few words. I've got some questions for you, David, based on different issues that we've wrestled with on the podcast mostly related to your worldview. And then Bruce would like to have a little bit more in-depth conversation both on cosmological heat death, something that we've, I don't know, we keep coming back to it. I think we might be the only podcast out there that does. And then probability. Yeah, David, you don't seem like the kind of person who likes someone going on and on about how great your work is. So let me be very succinct here. I still remember the feeling of first listening to Beginning of Infinity four years ago. Each chapter was like an explosion in my brain. Let's just say your work has changed my mind about knowledge, reality, how I treat my children and what a human is. I've been on here with Bruce about 50 episodes, listening and talking about The Four Strands of Reality and related ideas. And I only wish I had until the heat death of the universe to keep wrestling with these ideas you have introduced me to. So thank you, David. Thank you so much.

[00:02:22]  Bruce: And I wanted to say the same thing. I really, I read your first first book, The Fabric of Reality before Beginning of Infinity came out. So I'm one of the early adopters of—

[00:02:33]  Unidentified speaker: Old school.

[00:02:33]  Bruce: Yes, since most people seem to have introduced through Beginning of Infinity. But I had a, I've mentioned the story from on the podcast elsewhere. We had an episode where Luli [name spelling uncertain] was on and she asked me about it. But I was a religious blogger and I had a religious blogging friend introduce The Fabric of Reality to me and I loved it. Started to explore a lot of the ideas into it. And that's what eventually led to the idea of having a podcast, Theory of Anything, where we could, we kind of start with Popper Deutsch and we kind of explore out from there. I even ended up going back to school, ended up studying computer science, but go back to school based on the interest that came out of the follow up to your book, as I was trying to explore other books and other related ideas.

[00:03:16]  Unidentified speaker: Great to hear.

[00:03:19]  Unidentified speaker: Yeah, thanks.

[00:03:20]  Unidentified speaker: Okay.

[00:03:21]  Peter: So one thing that's always struck me about your work is how much continuity there is. In The Fabric of Reality or even articles you wrote much before, there seems to be many of the same themes that you hit on in Beginning of Infinity 15 years later. Thinking about human universality, optimism, progress, the growth of knowledge, explanations and so on. Obviously, you were changing and growing, just like any of us. But I do wonder, would you say your basic worldview formed when you were younger?

[00:03:56]  Unidentified speaker: Was it from reading Popper?

[00:03:58]  Peter: Or was there a teenage David Deutsch into, say, pessimistic postmodern philosophy who thought problems aren't soluble and humans are cosmic scum?

[00:04:09]  Unidentified speaker: If so, what changed you?

[00:04:12]  David: Well, Popper was the sea change in my worldview. So before Popper, it wasn't that I was irrational and pessimistic and all that. Before Popper, I was only interested in physics. And after reading Popper, I realized that you can't understand physics without understanding, for example, epistemology. Because there are, in the prevailing views about physics, in particular, quantum theory, but also other branches of physics, there are simply bad epistemological theories embedded in with the physics theories, which are spokes in the wheels and prevent progress. So I got interested in epistemology in order to sort out the logjam in physics or try to sort out the logjam. And it's a bit like somebody trying to write their great novel, and there's a leak in the roof, and it's dripping down onto the page, and you can't carry on writing until you fix the leak. So I tried to fix the leak, and then I saw that there's a whole load of other stuff going wrong, and it's connected with the stuff I'm writing about. So that's how I got interested in these other things.

[00:05:46]  Peter: And would you say that your philosophical interests, your in epistemology and critical rationalism, have influenced your work as a physicist?

[00:05:57]  David: Yes, although causally, I think it's the other way around. I mean, I was trying to solve some problems in physics. Like making sense of the foundations of quantum theory, connecting the theory of measurement to the basic structure of physics, following Everett in that respect. And so the driving force, initially, the driving force was was physics. But I got interested in these other things in their own right. I mean, of course, I read Dawkins' Selfish Gene. And like many other people, you know, that that that just changed the direction of my thinking.

[00:06:49]  David: And then saw the connections. Then I got interested in connections themselves, which is why I wrote The Fabric of Reality. That I saw that all these things I was trying to understand are actually connected with each other. And that people make, you know, they make a mistake about, let's say, evolution. And it turns out that the reason they're making that mistake is that they're making a mistake in epistemology. And of these four strands, they're not the four strands of the universe, they're just the four strands of knowledge that we have a great deal of understanding about. Those four strands are all connected, and they all have characteristic errors in them which need to be corrected. And they're kind of all the same error. And that also attracted me to think about it. Because as it says in the beginning of The Fabric of Reality, I think, all those four strands have in common, that in some sense accepted as the prevailing idea, and in other sense, contemptuously rejected as the fundamental idea. Both at the same time.

[00:08:19]  Bruce: I just barely read that in Fabric of Reality. That's exactly what you said.

[00:08:22]  Unidentified speaker: I thought that was really interesting.

[00:08:25]  Unidentified speaker: Yeah.

[00:08:25]  David: And I think it's still so, although I've been trying to push back against this. And I rewatched Bronowski's The Ascent of Man for the sixth time. And I saw that that's what he was trying to do as well. He's like this guy, you know that meme cartoon where this one person is saying, yes, you are all wrong. And then there are ranks and ranks of people in the cartoon, like all faceless, the same. And this one guy is saying, yes, you are all wrong. Well, that's how I see Bronowski.

[00:09:01]  Peter: If I might say, interject one thing about Bronowski, The Ascent of Man, I recently read the book, and I got so much more out. I think the documentary is a little bit slow for modern audiences, maybe. I wasn't really grasping what he was trying to get across. But when I read the book, it was just probably one of the best science books I've ever read in my life. And now I want to go back and rewatch the documentary.

[00:09:28]  Unidentified speaker: I agree.

[00:09:29]  David: I mean, I think his slow delivery, I really like it. Maybe that, you know, old or something. I think he's not many people can can deliver an explanation and pause for thought and not lose the audience, at least not lose me. I guess I'm just, you know, he pauses at exactly the right moment when I want to think as well.

[00:09:55]  Unidentified speaker: I see.

[00:09:56]  Unidentified speaker: Yeah.

[00:09:57]  David: And I don't know anyone else who can do that. I certainly can't do it.

[00:10:00]  Unidentified speaker: Yeah.

[00:10:01]  Peter: Maybe it's just when you've been more acclimated to the modern style of documentary or film.

[00:10:06]  Unidentified speaker: That's yeah.

[00:10:07]  Unidentified speaker: Yeah.

[00:10:08]  Unidentified speaker: But I mean, even to go back and watch some things from the 50s, it's just, it's, it takes, it takes more effort.

[00:10:14]  Unidentified speaker: Double speed.

[00:10:15]  Unidentified speaker: Right?

[00:10:17]  Peter: Well, anyway, let's just go through these questions if that's okay.

[00:10:21]  Unidentified speaker: Yeah.

[00:10:21]  Peter: Like I said, based on different, different things that Bruce and I have wrestled with on the show for the last, well, for me, 50 episodes and Bruce for the last 100 episodes. Let's, let's move right on to free will, if that's okay. You know, I used to be the kind of guy who was into Sam Harris and read his book on free will, and was telling people at parties that there's no free will. But I kind of readjusted my thinking a little bit on that. Popperian Donald Campbell, who of course you know, I'm sure, proposed the idea of downward causation. For our listeners, downward causation is the idea that big things influence little things, just as little things influence big things. I could, I've got a quote here about that. Maybe that's, maybe there's a more sophisticated understanding of that, but that's what I get at least.

[00:11:18]  Unidentified speaker: I mean, it makes some sense to me.

[00:11:20]  Peter: So, human minds influence the quantum world, just as the reverse. You have your own counter to reductionism in the form of the copper atom on the statue of Winston Churchill's nose thought experiment. I'm sure most people, most of our listeners know about that.

[00:11:38]  Unidentified speaker: Are these conceptions of free will the same or related?

[00:11:43]  David: I think they're related, but I think that trying to understand free will or many other things in terms of causation is already risking going down the wrong path because the concept of causation has built into it a concept of time, so something earlier can cause something later, but something later can't cause something earlier. But I think it's more fruitful to think in terms of explanation. Because for example, and my favorite example of in this regard, if you want to explain the state of the universe at the Big Bang, and you start thinking of that in terms of causation, then you're naturally going to say, well, what caused the Big Bang? And then you're going to go wrong. You'll either say it was some earlier universe that caused the Big Bang, or it was God or something, and those are well-known dead ends.

[00:12:57]  Unidentified speaker: So that's not an interesting question, what caused the Big Bang?

[00:13:00]  David: No, it's an interesting question. How do you explain? But the question ought to be not what caused the Big Bang, but how do we explain the Big Bang? What kind of explanation of the universe can tell us what the Big Bang must have been like or should have been like or could have been like or whatever the right mode of explanation is?

[00:13:29]  David: So similarly, when we want to explain things in real life, we sometimes want to know what caused them, but often that's completely uninteresting. The atom at the copper atom in the tip of Churchill's nose is something that can be explained in terms of things before, but it's not atoms before. It's human intentions and strivings and morality and that kind of thing. But not everything, like if we want to explain Napoleon, you might ask, why did he lose the Battle of Waterloo? If you think in terms of causation, in terms of this concept, the explanations have to be in terms of earlier causes, you'd go back to Napoleon's childhood and you try to dig up facts about whether he played with toy soldiers or that kind of thing. Whereas that is not the explanation that we're looking for. I mean, in principle, it could turn out that that is the explanation, but that need not be the explanation. The explanation is more likely, more in terms of the kind of explanation we want for historical events. It will be in terms of understanding what political situation, what military situation Napoleon came into, and what problem he was trying to solve, and why he thought certain things were the solution to the problem. Some of them were, some of them weren't. The interesting thing is, what's the difference between those? What's similar among those? And so on. Rather than, you know, what events in his childhood led him to be a great dictator?

[00:15:37]  Unidentified speaker: Great answer.

[00:15:39]  Peter: One follow up to that about free will. In, it seems to me, I should have gone back and read the section, but in Fabric of Reality, I think that you link free will to the many worlds interpretation. I've heard that between Fabric of Reality and Beginning of Infinity, you changed your mind on that.

[00:16:02]  Unidentified speaker: Yes.

[00:16:02]  Unidentified speaker: Is that true?

[00:16:03]  David: Yes. I've somewhat changed my mind. I mean, if you read that passage in Fabric of Reality carefully, you'll see that I don't actually claim that the explanation of free will is parallel universes. It's more of a negative thing. I wanted to show that counterfactuals can make sense, can be compatible with the laws of physics. And so the kind of argument that says there is no free will because counterfactuals aren't real doesn't work because there really is such a thing as what would have happened if you hadn't made the decision.

[00:16:49]  Unidentified speaker: Interesting.

[00:16:50]  David: Namely, it's what happens in the other universes. But I think there are many more counterfactuals that aren't explained under many universes' quantum theory, such as, you know, what would it be like? What would the world be like if quantum theory wasn't true? That's a counterfactual that is perfectly meaningful, and yet it can't be expressed as asking about other universes. Because, you know, in quantum theory says that certain, a certain range of universes exist, but most logically possible universes don't exist at all, such as ones where quantum theory isn't true. But it's possible to argue about those and explain things about those and think about things like, like why is quantum theory the way it is? That kind of thing. So and I don't think that's the problem with free will anyway. By the time I got to beginning of infinity and even more now, I think that the problem with understanding human volition and so on is not what caused it, what caused the decision. It's, it's, it's, we have the feeling that we create something, we're creating something new, we're bringing something new into the world. In other words, when I make a decision to come on a podcast or not, I don't want to think of that decision as being caused by the state of the universe at the Big Bang, or even by the state of my digestion when I made the decision. It's a mental process that has reasons where the reasons are in me, and I created the new thing, the new thing that was the reason for doing this.

[00:19:07]  David: So it's a creative act, and in a creative act, something new is created, and that is what's wrong with the sort of deterministic world view, that it pretends that humans do not create novelty. So when Einstein came up with the theory of relativity and wrote it down, the anti-free will people have to say, it wasn't Einstein who caused this, it was the Big Bang. And I think that isn't true. Before Einstein, that knowledge didn't exist, didn't exist in the world. And the world wasn't being driven towards it. Einstein was driving, not the world. So again, this is something when we want to explain why did Einstein invent relativity, discover relativity, create relativity, we have to talk about what kind of problems he was solving. What kind of problems he thought he was solving? What kind of mistakes was he making? This is by the way, a big thing about Popper. When he talks about other thinkers, he's always asking what problem were they trying to solve? And as he points out, the ancient Greeks, the ancient philosophers were not nearly so stupid as they seem when you just talk about their theories and not their problems. When they say the theory of the world is floating on a large vat of molasses or whatever they thought, the issue is not why they came up with that silly idea or how silly are they to come up with that idea. It's what problem were they solving that was solved by that idea?

[00:21:13]  David: Because that is also what leads to the next idea and to successive improvement and so on, which is the thing that Popper is reaching back to think how important that was in the pre-Socratic philosophers, which is a strand that comes right up to the present day through the Enlightenment, the Scientific Revolution and so on.

[00:21:35]  Peter: So problems are really what's driving progress and civilization more than theories.

[00:21:42]  David: In fact, my colleague, Matthias Leonades [name uncertain] said to me once, and I very much agree, that the concept of a problem in Popper's philosophy is his most important contribution to philosophy, because he means something slightly different to what anyone before him meant by a problem. And it's a very rich concept in his philosophy. So, the growth of knowledge, the growth of scientific knowledge starts with a problem, doesn't start with evidence. That, you know, that already thinking it starts with evidence takes you totally down the wrong path. It starts with a problem, and it ends with a problem, because once you solve the first problem, the result is a new problem.

[00:22:36]  Bruce: Can I ask about the term free will itself? Obviously, that's a very loaded term in people's minds. Douglas Hofstadter suggested, I don't know that I agree with him on this, by the way, but he suggested the idea of using just the term will instead of free will to try to get rid of some of the baggage, philosophical baggage that comes with it. I've personally found that a little hard to do, but could you maybe comment on that? But why do you call it free will? Is there other terms that could be used, and do you have something? Clearly, that is a term that could mean many different things.

[00:23:12]  David: Yeah, I don't want to get hung up on what to call things. I will gladly call it a black dog, if somebody wants to use that term, just as long as we don't define away what we're talking about.

[00:23:29]  David: So, I'm a bit suspicious of the idea of calling free will will, because of what you're dropping. I do things like sneeze, that in some sense, I wield it, in that it's sneezing is caused by the so-called voluntary muscles in the face and oral cavity and so on. And so, in a sense, I am ordering my body to sneeze. In another sense, I wouldn't normally call that an exercise in my free will, even though it is an exercise in my will, and I could have suppressed the sneeze, and I chose not to. But that's not when I proudly say, I am an entity which has free will and my computer, though it's much smarter than me in many ways, doesn't have any free will. It's not the sneezing behavior that I'm referring to. It's the decision behavior. It's the not just choosing between options, but creating a new option. That that's what the computer can't do. That's what I'm not doing when I'm sneezing. But I am doing it when I'm speaking to other humans and when I'm working on physics and whatever.

[00:25:00]  Unidentified speaker: Thank you.

[00:25:03]  Unidentified speaker: Okay, well, moving right along to optimism.

[00:25:07]  Peter: So it's kind of a random tweet, but it's just really stuck with me over the years. One of my favorite tweets of yours or hosts, I guess you say now, every human who is functional at all is rational and creative and capable of being more so. Only a tiny minority do not leave the world a little better than they found it. I love this statement because it emphasizes that as flawed as we are, each of us or just about every one of us is a net positive on the world in our own way.

[00:25:46]  Unidentified speaker: But I do struggle with this too.

[00:25:49]  Peter: If humans are so good, where does all this suffering come from? I know that you are very attuned to world events in Israel and Ukraine and other places. So you're quite familiar with how messed up the world is. Couldn't it be just a small number of people who leave the world a better place than they found it? Or where does the just about everyone come in?

[00:26:19]  David: So first of all, thank you very much for liking that. I don't know whether it was a post or a tweet. Was it before or after?

[00:26:27]  Peter: I think it was from, I think you've maybe reposted it, but it was from a couple years ago, at least, I think.

[00:26:32]  David: Right, so it was a tweet then.

[00:26:34]  Unidentified speaker: Yeah, it was a tweet, okay.

[00:26:36]  Unidentified speaker: I'm glad you like that.

[00:26:37]  David: The reason I tweeted that was that that is a quote from the introduction of my book. I almost said forthcoming, but I don't know when it will be forthcoming.

[00:26:49]  Unidentified speaker: Oh, okay.

[00:26:51]  David: That is from the introduction, and one of the uses of Twitter or X is to try out ideas and see how they bounce off people. And I couldn't quite reproduce in my mind what effect this statement would have on people who didn't already believe it, didn't already agree with it. And the outcome was quite good. I mean, most people didn't sort of hate it or misunderstand it or whatever, but many people like you, I'm sure, are, though they haven't said this, I think, would like to think it's true, but are not sure. Now, I think that the... So first of all, the origin of suffering, if I may solve the problem of evil right now, the origin of suffering is a combination of ignorance and anti-rational memes. So either people don't know the answer or they're prevented from improving their existing answer by psychological blocks of various kinds. And most of those are caused by anti-rational memes. So perhaps I should say psychology in general, but most bad psychology is caused by anti-rational memes. So I can just stick in another observation here, just to orient what I'm saying. When I first went to America, I went to Texas, and I encountered libertarians for the first time. And I was quite, you know, for a while, I was kind of enthusiastically libertarian, and then eventually I connected it with Popper's ideas, and anyway, they had a slogan about immigration. The slogan was, two hands, one mouth. I thought, that's a brilliant slogan, because what that is saying is that the characteristic human behavior is to make things, to improve things.

[00:29:27]  David: So, you know, you encounter a flat tire, and you want to blow it up to, you want to get the jack or not. But if you want to do something, you want to do that rather than shoot it with the gun and make it go even flatter. Most people, most of the time, so most people most of the time are trying to improve things. They're trying to improve their own lives. They're trying to understand the world better, not worse. And the two hands, one mouth, if you live in a society, the rest of the world feeds you. You're not a self-sufficient farmer. You are exchanging things with other people in the world, with your two hands, and you're consuming the fruits of that label with one mouth. And so you end up with there being more good stuff in the world than there was before you came into the world. Now, there are people who do the opposite. There are people who see something working, and they want to stop it working. They see someone happy and they want to make them less happy. But I think that's actually very rare. You have to be kind of, most criminals are still kind of okay in the areas where they're not criminal. You have to be quite a bad criminal, you know, like one in a thousand to actually do net harm in your life.

[00:31:14]  Unidentified speaker: Wow, that is optimistic.

[00:31:17]  Unidentified speaker: One in a thousand criminals, okay.

[00:31:20]  David: Well even if it's only one in a hundred, it's still overwhelming.

[00:31:23]  Unidentified speaker: Yeah, yeah, okay.

[00:31:26]  Unidentified speaker: I can buy it.

[00:31:27]  Unidentified speaker: Thank you.

[00:31:28]  Unidentified speaker: Wow.

[00:31:29]  Peter: Okay, moving on to something that we've talked about on the podcast at length, wrestled with, which is genes, you know, kind of like the free will. This is another thing that you sort of twisted my mind around on a little bit. I used to be more tuned in to evolutionary psychology.

[00:31:51]  Unidentified speaker: And, you know, I was the guy that was told, oh, that's just a biological impulse and all this.

[00:31:56]  Peter: I'm not quite sure I've come around quite to the level that you are, but I definitely have a new idea of what humans are. Bruce has made the case on the podcast that our genes coerce us, which I think I'd never heard it quite put like that before. I think it's a pretty compelling way to put it, partly because it seems to separate our genes from our minds in a way, our impulses from our minds. So our minds might not feel like eating, as an example, but our body generally finds a way to make us eat. And of course people do go on hunger strikes, yes, but that's rare.

[00:32:46]  Unidentified speaker: And I don't think they're having much fun.

[00:32:50]  Peter: And does this conception of our genes coercing us make sense to you? And if not, what is the relationship between our impulses and our genes?

[00:33:04]  David: So I don't think it's a good picture to think of our genes coercing us, although it can happen. And certainly in, say, our prehistoric state, you could say that it was our genes coercing us in the situation where there wasn't much food, or wasn't any food, and we would like to stop being hungry, but we can't and therefore we're in a state of coercion. That is the kind of thing, you know, we, the human species, came into existence already in a state of enormous suffering. And it tried to reduce that, and that should have taken like two or three generations, but in the end it took thousands and thousands of generations. So, in those days, I think it would have been fairly accurate to say that our genes are coercing us. But more recently, even before the Enlightenment, as soon as there was civilization, the main source of coercion was definitely other people. It, you know, parents, robbers, kings, that sort of thing, which means that there was a lack of knowledge of how to structure society in such a way that it won't coerce people. That there might sometimes not be enough food, although, okay, that still did happen. But it wasn't the main thing that caused most suffering of most people. And now, I think, you know, the closer we get to now and in the West and so on, that it's not our genes, like, nobody dies of hunger in our society. And there are far more people. You said hunger strikers and so on don't enjoy going on hunger strike. I think they often do.

[00:35:25]  Unidentified speaker: Fair enough.

[00:35:26]  David: And anorexic people, teenage girls, who decide that they don't want to eat. It's not that they're enjoying their life, but they're enjoying that decision because perhaps, I don't know, I'm not a psychologist, perhaps it was the only decision, effective decision that they ever managed to make in their life. And they're going to cling to it because that gave them agency and nothing else in their life ever did. So I'm just throwing it out off the top of my head. I don't know what the actual psychology is, but it's not lack of food in the environment. To them, not eating is the solution, not the problem. They don't say, I wish I could. They don't think, I wish I could eat. They're thinking, I wish something or other, which they hope to get by not eating. So yeah, I don't think it's true that it's the genes. And similarly, when the, what are they called, incels? When the incels want to have sex, and no one will have sex with them, they're not being coerced by their sex drive. They're being coerced by their bad ideas, which they got either from anti-rational memes or maybe in some cases mistakes. But if they, if it was just a mistake, then it should be corrected when they, when they find better ideas. So, yeah, I, I, I, so, yeah, I don't think we're coerced by our genes in any, in any, um, meaningful sense nowadays. And probably not for a very long time in the past either.

[00:37:38]  Peter: But, okay, so just to push back a little bit, I mean, there's still, if someone goes on a hunger strike, they're still, they're still countering something inside their bodies, right? That's there that they can't get away from.

[00:37:56]  David: No, not necessarily. They, they, they are interpreting their hunger in terms of their, for example, the political agenda, the political objectives. They think that what they're doing is striking the oppressor and proving the oppressor wrong. And that, that's a very, very positive thing for them. And mere sensation has to be very extreme before it coerces you. Again, my favorite example is, is skydiving, where we allegedly have an inborn aversion to heights. I'm not sure I believe the experiments, but let's suppose for the sake of argument that we do have an inborn aversion. If it's not inborn, it's, it's learned very soon after, after birth. Then, you know, you go up in an airplane and, and you've got the parachute on and you want to jump out or you don't want to jump. You know, some people chicken out at the last moment. Some people want to do it. Some people, when they finally get to the ground, they say, okay, I'm never, never doing that again. And other people say, can I go around again now? Now, the difference between those two people is not in their genes. They have the same genes. They experienced the same sensations of falling and of having the wind whistle past them and seeing the ground coming up towards them. They had the same animal experiences in their life. And one of them interpreted it as a horror that they never want to experience again. And the other one interpreted it as the best thing that's ever happened to them. And there can be anything in between.

[00:40:06]  David: So, they are not, their problem is it doesn't come from their genes. Humans can reinterpret sensations to an enormous extent, a far, far greater extent than ever happens in everyday life. You know, it may happen that you have unbearable pain when you're going to die or something, when you have an incurable disease and that kind of thing. Then, yes, your body, and I suppose you could say indirectly your genes, are coercing you then. But it's not a thing that is an important factor in life.

[00:40:49]  Bruce: I'm actually glad to use the example of pain, because I've actually struggled with pain throughout my life. And to be honest, I feel very coerced by those sensations of pain. And I'm very glad that we've got big enough brains that we've been able to invent like medications to be able to stop those impulses, so that the pain does not coerce me in ways that I don't want to be coerced. But I definitely do feel like pain is a very, can be, I mean, obviously, it can also be, is there for a reason. But it can be a very coercive force in my life is what it feels like to me. And I don't doubt that you're right that I can reinterpret it. But I don't find that the easiest thing either.

[00:41:31]  David: No, no. But then that's also true of things that you, I'm sure, would agree are entirely a matter of ideas. So, you know, you can say to somebody that they would be much happier if they weren't a Nazi.

[00:41:55]  Unidentified speaker: Right.

[00:41:56]  David: But even if they, when they agree with you, they might not be able, it might not be an easy thing for them to change. For one thing, it's never good enough to prove someone wrong or to persuade them that they are wrong. You have to give them what I call somewhere to jump to. If you pull a rug out from under them, unless you give them somewhere to jump to, they will end up with the same rug somehow.

[00:42:25]  Unidentified speaker: Right.

[00:42:26]  David: You've got to solve their problem or help them to solve their problem of how to get away from this idea that is hurting them.

[00:42:39]  Unidentified speaker: That's not easy.

[00:42:39]  Unidentified speaker: It may take a lifetime and you may fail.

[00:42:43]  David: Creativity is not easy and nothing is ever guaranteed. And I think that coming to a better frame of mind about pain, if the pain is large, is particularly hard. I think Thomas Szasz wrote a book about pain. I haven't read it, but I would expect him to have good ideas about it.

[00:43:12]  Bruce: Just to clarify one thing, though, in the Nazi example you just used, you would, though, call that idea an irrational meme, and you would see it as a form of coercion, correct?

[00:43:24]  David: Probably. One can never be sure about how the mind gets into its states, because it's never deterministic. So I would guess that most Nazis got to be Nazis because of their parents, because their parents gave them a conception of nationhood and history and themselves and other people and force and a whole bunch of things, which made an unlit bonfire, which the spark of hearing a Nazi speech could ignite. So, I blame the parents. But yes, I think the Nazi, I would guess in most cases, it is a matter of bad things being done to them.

[00:44:26]  Peter: One more question about genes and minds. So, even if we accept on some core level that humans are universal explainers, I think that makes a lot of sense to both Bruce and myself.

[00:44:41]  Unidentified speaker: What about genetic disorders that affect the mind?

[00:44:46]  Peter: Like, I'm thinking about something like Down syndrome, where, you know, I mean, you have humans who can oftentimes speak and make jokes and are pretty functional in many ways, but clearly, their capabilities and personalities are radically affected by their genes, right? Like, how does that fit in to your hypothesis here?

[00:45:13]  David: I'm not sure it's helpful to think of their personalities as being controlled by their genes. Their personalities are a way in which they are responding to the inadequacy in their brain. And again, I'm not sure how much is known about what exactly the wrong functionality is in the brain of Down syndrome people. But let's say it's insufficient short-term memory or something.

[00:45:46]  Unidentified speaker: I suppose it could be that.

[00:45:48]  David: Then if you grow up in a society where you need more short-term memory to be happy, then you will be unhappy. It could be, and I would guess that something like this must be true, that there is a way of bringing up Down syndrome children such that they will be happy, such that they are capable of solving the problems that come up in their lives, and therefore have a fruitful human life. To go to the other extreme, I'm sure that some hundreds of years ago, society would do the opposite. Society would deliberately put them in situations where they cannot cope, and then ridicule or hurt them or whatever for not being able to cope, because conformity was a value in society. And if somebody was unable to conform in a certain way, then things were done to them that would make it even worse. Similarly, I think that there will be ways of doing things to people such that their lives will be better instead of worse. Although, whether that will happen before Down syndrome is physically cured, I don't know.

[00:47:32]  Bruce: So, can I ask a follow-on question to that, Peter? So, you actually just said something that's very similar to what I think I said when we were discussing this on the podcast. So, I wanted to explore a little bit further and kind of pick your brain on this. So, there probably are human beings that are not universal explainers. And here, I have in mind maybe somebody who has no neocortex at all. So, they're not ever going to be able to learn language or live a normal life. But then, you've got this group in between, like Down syndrome, which we call mentally challenged. And for the sake of argument, since we don't really know for sure what's wrong, let's go with your off-the-cuff theory here that there's a lack of short-term memory or some sort of hardware defect that leads to a lack of short-term memory. So they struggle to learn in our society compared to somebody who doesn't have that lack of short-term memory. There are two things that maybe come out of this, if I'm taking this idea of a universal explainer seriously. One of the ideas is that the fact that they're a universal explainer, presumably a Down syndrome person is still a universal explainer. They can learn language, et cetera, et cetera. That you could have, because of circumstances and partially maybe hardware problems and partially maybe society hasn't created the necessary knowledge to overcome it yet. You could have someone who really does learn slower and does not learn as much as somebody who is not mentally challenged in society.

[00:49:09]  Bruce: But the other prediction would be that presumably there would be some way to create the necessary knowledge that would allow them to compensate.

[00:49:17]  Unidentified speaker: We just may not know what that is as of today.

[00:49:20]  David: Not compensate in the sense of learning faster. That may not be, unless we think of electronic add-ons to the brain or whatever. But just environmentally, it might be that they learn slower. But the important thing is, do they solve the problems that they have?

[00:49:40]  Unidentified speaker: Yeah.

[00:49:41]  Bruce: So the question we raised in the podcast was, could you teach someone who is mentally challenged to do quantum physics? And I actually argued probably yes, even if that would be a very difficult thing. They'd have to be interested in it, they'd have to want to do it. It would probably take them much, much longer. Maybe even arguably, you'd have to be able to extend their life to past 70 years or whatever. And I know Peter was a little skeptical of that. I admit, even I feel a little skeptical of that claim. But it does seem like that is something that would come out of the idea of a universal explainer, that they should be able to learn a complex subject like quantum physics, in theory, if maybe at a slower rate.

[00:50:26]  David: Well, it does depend on what exactly the hardware floor is. Because if it's short-term memory, that's one thing. Because one can build up ways of getting around that. But if it's, I don't know, the pattern buffer or something, like the complexity of an idea that you can hold in your mind at the same time, that might be harder to get around. And again, there's a difference between what we could do with hardware improvements, and what we can do with purely environmental improvements, like how you treat the person. Right. I think, my guess is that even a chimpanzee could be fully a person if the right program was installed in their brain. But it may well be completely impossible to install such a program just by doing things to the chimpanzee.

[00:51:39]  Unidentified speaker: Right.

[00:51:41]  David: By talking to it or whatever.

[00:51:43]  Unidentified speaker: Right.

[00:51:43]  Bruce: Teaching it sign language, right?

[00:51:46]  Unidentified speaker: Yeah.

[00:51:46]  David: So it may not be possible that way. But I think the hardware, I find it very implausible that the hardware isn't capable of doing the thing because their brains are like, I don't know, one quarter the size of ours or whatever it is. And we're, we're, we're not using, we don't need to use more than a quarter of our brain to do any particular thing like have a conversation.

[00:52:15]  Unidentified speaker: Right.

[00:52:17]  David: The rest of the brain is doing stuff. So, I think, so the, it's a matter of hardware and software. The, the, the person is a program. The brain is the hardware on which that program is running. And I think it's very plausible that the hardware of a chimpanzee can run a person program. It's just that we don't know how to install that program. And by the way, it would be, it would be a crime because that person would have been installed into a chimpanzee with all the disadvantages that that would have. And, and have, have, it's like making someone down syndrome on purpose.

[00:53:04]  Unidentified speaker: Right.

[00:53:06]  Unidentified speaker: Thank you very much.

[00:53:06]  Bruce: Actually, that clarified a lot of things that we've discussed in the past and how you look at them. So I hadn't actually written any of those questions down, but when I saw the opportunity, I really wanted to ask about that.

[00:53:17]  Unidentified speaker: So thank you.

[00:53:19]  Peter: Well, I think that actually leads well into my question about universality. So David, when I first read your book, I think I had a pretty basic view, if not an outright misunderstanding about what you were saying about human universality and our capacity to create an infinite knowledge creation and explanation. At first, I thought you were saying that human universality was kind of a consequence of our brains being universal computers.

[00:53:54]  Unidentified speaker: Right.

[00:53:54]  David: No. By the way, that's my fault. I did not stress that distinction, I think, at all in the book. I think I made the distinction, but it's a very fundamental thing that there are two kinds of universality. One is hardware and one is software, and they're not the same. And so...

[00:54:17]  Unidentified speaker: Okay.

[00:54:17]  Unidentified speaker: Well, it's not my fault then.

[00:54:18]  Unidentified speaker: Okay.

[00:54:20]  Unidentified speaker: Definitely not.

[00:54:21]  Peter: But Bruce helped me to understand that universal computers are basically a dime a dozen. And I now understand that maybe you're making something more like an analogy between human minds and universal computers.

[00:54:38]  Unidentified speaker: Is that right?

[00:54:38]  Unidentified speaker: An analogy or...?

[00:54:40]  David: No, it's [wording uncertain] analogy. So, the two abilities are connected by the fact that the program, which is a person, has to run on hardware, which is a brain. So, that's the connection. It has to be a universal computer, because otherwise, as soon as you make a computer not universal, they drastically reduce the types of program it can run. If you take a computer chip, it's a universal computer in, and then you delete one transistor, it'll just work pretty much the same. Every so often, there'll be an error. If you delete a lot of them, the thing will crash. But if you see what the problem is, you can change the program to work around that. So, it'll still be universal. It's just that you'll have to write a slightly more complicated program for it to be able to harness its universality. I'm still talking about Turing universality, computational universality. So, if you destroy a little bit of it, it's still universal, but you have to write a more complicated program. And people have very ingeniously shown that you need actually extremely little functionality in order to make a universal Turing machine functionality. So, so long as there's memory there, you can work around and work around and work around the workarounds. And until the functionality is exactly the same as it was before.

[00:56:41]  Unidentified speaker: Exactly the same, just more complicated program.

[00:56:43]  David: And if you keep destroying the thing, eventually you'll get to the place where it really is not possible to write a suitable program to get around the lack of functionality. And before you get to that, it'll get more and more difficult to squeeze the program into a smaller and smaller amount of memory, which is still left on the chip to still make it universal. So that's hardware. Now, I think with software, and people don't say, why isn't there a continuum between Turing machines and less capable computers? Why isn't there a continuum between non-universal computers and universal computers? Why is it just a jump? Well, it's because of the nature of universality. The thing that causes the continuum is the difficulty of writing programs that harness its universality. But whether it's universal or not is a qualitative thing. Now, when you think of a person program running on hardware, I think that program has to be able to harness the universality of the computer. But how it does that is very, very insensitive to errors in the hardware. Because the creativity program, here we are, the program itself is the thing that's writing the workarounds, not the programmer, because there is no programmer. So if there's something wrong with your brain, if a few neurons cut out, you don't even notice because you're just doing the work around. There are probably work around processes working at the unconscious level all the time, to cope with things like that. What if you lose a bit more of your brain? Well, then the work around is going to be harder to do. Eventually, it'll be impossible.

[00:59:15]  David: But, so, the explanatory universality is at a level of abstraction where it simply needs to have a universal computer to run on. It doesn't get less explanatorily universal if the hardware is damaged. It just means it's got to think a bit more to get around the hardware damage, until it becomes impossible, or probably in practice, until it takes a lifetime to think of the, you know, or it takes too long to think how to do it. People get around amazing disabilities. So apparently we have face recognition hardware in our brains. I saw a documentary about people with this disability, and they, you know, they...

[01:00:23]  Unidentified speaker: Face blindness, right?

[01:00:24]  David: Face blindness. And they can live a normal life. They simply learn to harness the hardware that they have to perform, because the hardware that they have is still universal, they can use it to perform the relevant computation. Not as fast as the dedicated hardware, but fast enough to live a normal life. So instead of recognizing someone's face, you learn to have a sort of... When you meet somebody and you want to remember what they look like, you have a checklist of, this person is blonde and blue eyes, and has a beard, and you better choose things that can't change easily.

[01:01:14]  Unidentified speaker: Right.

[01:01:16]  Bruce: There was a guy with face blindness that had his wife wear a bow in her hair so he could recognize her at a party.

[01:01:24]  Unidentified speaker: Right.

[01:01:26]  Unidentified speaker: Right.

[01:01:26]  David: So that's a workaround. And to the extent that the workaround works, you lead a normal life. If the workaround isn't good enough, you can think of a better workaround.

[01:01:36]  Unidentified speaker: Right.

[01:01:37]  Unidentified speaker: And so on.

[01:01:39]  Peter: One more thing on the universal explainer hypothesis. One of the interesting push backs I think I've heard on that is that it's kind of a tautology in that, I'm sure you've heard this before, in that if something is beyond human understanding, how would we ever know by definition? So how do we know that we're universal explainers from that perspective?

[01:02:09]  David: I think this is harking back to an older pre-Popper conception of what know means.

[01:02:16]  Unidentified speaker: Okay.

[01:02:18]  David: So how do we know for sure?

[01:02:19]  Unidentified speaker: We can't.

[01:02:21]  David: We could be mistaken about anything at all. You could be mistaken that you have a navel. And when did you last look? So it could be that there are things beyond our understanding. But the proposition that there are things beyond our understanding is a fundamentally bad explanation. It's like the archetype of all bad explanations, because it says, I'm going to postulate anything I like, and you can't be sure that it isn't true. Okay, since that's always true about anything you might say, it's irrational to take it seriously.

[01:03:19]  Unidentified speaker: I love that, the archetype of bad explanations.

[01:03:22]  Unidentified speaker: Okay.

[01:03:24]  Unidentified speaker: Okay, thank you so much, David.

[01:03:27]  Unidentified speaker: Bruce, do you want to...

[01:03:29]  Unidentified speaker: should we...

[01:03:30]  Unidentified speaker: Yeah, can I do my cosmology questions?

[01:03:32]  Unidentified speaker: Please.

[01:03:34]  Unidentified speaker: Okay.

[01:03:35]  Bruce: So, in the fabric of reality, the final chapter was my favorite chapter. It was perfect because the whole book was leading up to a kind of twist ending in a non-fiction book that forces you to rethink everything, right? And that was actually the chapter that caused my friend to recommend the book to me. So I was really intrigued with the Omega Point, because that's a big part of that final chapter. And so I decided to read The Physics of Immortality. And sorry, I have to explain a number of things to set up my questions. So I'm going to give a little bit of background here. So I found The Physics of Immortality very intriguing, but there were some aspects to it that I found very problematic. So I wasn't too surprised when in the beginning of Infinity, you walked back some of your support for the Omega Point Theory, okay? And in fact, you wrote that you felt the theory had been refuted by observation. So from page 451 of the beginning of Infinity, you said, a small part of the revolution that is currently overtaking cosmology is that the Omega Point models have been ruled out by observation. So now I found it interesting that Tipler actually argued something different on this point. And so my question, I'm going to first give you what he argued and then I kind of want to talk with you about the apparent difference of opinion here if that makes sense, okay? So Tipler claimed that the, and I don't know what a lot of these terms mean.

[01:05:04]  Bruce: So, but he says, the creation destruction of a baryon number by electroweak quantum tunneling can be used as a source of energy for by life and to power rocket ships, but that would also eventually lead to the collapse of the [wording uncertain], even if there was energy that was forcing it apart at this point. So, from one of his books, he says, it is not enough to annihilate some baryons. A substantial percentage of the baryons in the universe must be annihilated in over rather short time span. Only if this is done will the acceleration of the universe be halted. This means in particular that intelligent life from the terrestrial biosphere must move out into interstellar and intergalactic space, annihilating baryons as they go. The annihilation process will provide the means to traverse interstellar and interactive [quotation word uncertain] space. Now, he's invoking an idea that's very, very similar to an idea that you have in Fabric of Reality. So let me give the quote from Fabric of Reality now that he isn't, he's not quoting you or anything, but he's invoking a very similar idea. So from Fabric of Reality, this is in relationship to the Earth being next to the Sun, the Sun expanding to engulf the Earth. Says, now it may be objected that a huge, and this is quoting you now, huge and unsupported assumption that intelligent life will survive on Earth for several billion years. And even if it does, it is further assumption that it will possess the knowledge required to control the Sun so that they can continue to survive.

[01:06:38]  Bruce: One cannot predict the future of the Sun without making a, taking a position on the future of life on Earth, and particular on the future of knowledge. The color of the Sun 10 billion years hence depends on gravity and the radiation pressure on convention and nucleosynthesis. It does not depend on the geology of Venus, the chemistry of Jupiter or the pattern of the craters of the moon, but it does depend on what happens to intelligent life on the planet Earth. So if I understand Tipler's argument correctly, he's basically invoking the same idea that you cannot actually tell if the universe expanding refutes by observation his theory, which is based on a big crunch, because in fact, this will be determined by what life chooses to do.

[01:07:30]  Unidentified speaker: I'm just not enough of a physicist.

[01:07:32]  Bruce: I have maybe a minor background in it from a long time ago. And I'm not even some of these terms that he uses honestly sound like things out of Star Trek to me. They might as well just be tech jargon to me, right? So could you comment on the plausibility of what of Tipler's argument here that the big crunch cannot be ruled out yet due to possible choices life will make?

[01:07:58]  David: Yeah, so I should say, I'm not a cosmologist. And Tipler is. He's a distinguished cosmologist.

[01:08:07]  Unidentified speaker: Yes.

[01:08:08]  David: But I think the two sources of hope, the one that he cites there that you quoted and the one that I cited are different in kind. Because he has a specific idea in mind about what the laws of physics might be that would allow a particular way of stopping the expansion of the cosmos to happen. Whereas, I was, first of all, I was talking in terms of cosmology as it was known in 1997 or whenever I wrote that. I didn't want to say anything, postulate any new cosmology. So therefore, I gave Tipler's idea as an idea of what could happen. Even then, it depended on being able to use gravity and so on to store information at extremely high densities and that kind of thing, which there is no theory of that at the moment. So even I had to say, well, there could be. In other words, what I was saying is, there's nothing in existing physics that says we can't go on forever. Tipler was saying, there is something in existing physics that says we can go on forever.

[01:09:49]  Unidentified speaker: I see the difference, yes.

[01:09:50]  David: So there's a different logic, which means that I think that on the one hand, it means that when he has ideas about this, they can be refuted.

[01:10:02]  Unidentified speaker: Yeah, I was actually going to ask that.

[01:10:04]  David: To get around the refutation. Whereas, I'm just saying, I'm not that interested in what will happen in 10 to the power of 100 years from now.

[01:10:25]  David: It seems irrelevant to the important thing, which is that we don't know of anything that would stop us. So it's like in Newton's time, if somebody said, and I think, wait, wait, not Newton, Kepler. Kepler wrote what is essentially a science fiction story, or some people say it's the first ever science fiction story about going to the moon. And what Kepler realized was that the laws of physics, as he had now come to understand them, which is very crude compared with even Newton, let alone what we have now, that they did not stop, that there was nothing in them to stop us going to the moon. Now, the actual way he envisaged, I don't know what it was. It was something like gun powder, was it?

[01:11:23]  Unidentified speaker: Yeah, I think so.

[01:11:24]  Bruce: Trying to shoot them to the moon, right.

[01:11:27]  David: Yeah, so someone could say, well, that's ridiculous because in order to shoot someone to the moon, the acceleration from the gunpowder wouldn't [polarity uncertain] be enough to kill anybody many times over. So it can't be done that way. But that wasn't his point. His point is that physics, we're now at the point where we can say that physics, unless we discover some new physics that's going to stop us, physics doesn't say that we can't do it. Therefore, if that remains so, it's a matter of knowledge to get around it. Now, similarly with Tipler and surviving the dark energy and that kind of thing, I can think of ways of getting around the dark energy that are not the same as Tipler's one. I'm not quite sure why he wants to pin his hopes on this particular way that future science and technology might get around the problem. I think I suggested in The Beginning of Infinity, that one way of doing it would be to use the Dark energy? The expansion power of the dark energy to power things.

[01:12:52]  Bruce: I was about to ask you about that, actually.

[01:12:54]  Unidentified speaker: So, yes.

[01:12:55]  David: I understand that Tipler thinks there's a floor in that plan, but that's the same as the floor in Kepler's plan to use gunpowder. I'm not saying that I have a blueprint where the using the dark energy to generate free energy would be enough to solve all the problems of live of computation going on forever. I'm fairly sure it wouldn't be enough. What I'm interested in is that we don't know of anything that would stop us.

[01:13:35]  Peter: So if I go ahead, can I just interject one thing very quickly? Yeah, so if one of these optimistic scenarios like Tipler's omega point about the far future of the universe does not pan out or could not pan out, would that refute the principle of optimism? I mean, is that a problem that's not soluble?

[01:13:59]  David: If no such thing, if existing physics said that no such thing can happen, then that would refute the principle of optimism. Although you wouldn't lose too much sleep on that since it's 10 to the power of 100 is longer than I'm going to live anyway.

[01:14:22]  Peter: So heat death is not, is heat death a bummer or is it not? Is it something that's worth worrying about?

[01:14:28]  David: So heat death is an—[restart wording uncertain] that was the old idea of that existing physics says there's going to be a heat death.

[01:14:39]  Unidentified speaker: Okay.

[01:14:39]  Unidentified speaker: Oh, that's an old idea.

[01:14:41]  Bruce: Well, it's still accepted by many, right? But yes, it's definitely an older idea.

[01:14:47]  Unidentified speaker: Yeah.

[01:14:47]  David: I mean, that need not be true. People think that the law of increase of entropy is a sentence of doom, but entropy is much more our friend than our enemy.

[01:15:03]  Peter: But something human knowledge could counter then, optimistically.

[01:15:07]  David: It could counter it. So, for example, if this idea of using dark energy to generate free energy to work, then it would simply be pumping negative energy into the world. So, the fact that, sorry, negative entropy into the world. So, the fact that entropy is increasing otherwise, wouldn't bother us.

[01:15:38]  Unidentified speaker: It's doing that anyway.

[01:15:39]  Unidentified speaker: It increases to infinity, right?

[01:15:41]  David: The thing we want is for us to be able to lower our entropy. It doesn't matter what happens to the universe. So, another way this could happen is that we could make black holes dive into them and come out into another universe. So, that's a, you know, if I was inventing things in the way that Tipler does. By the way, he wouldn't accept that he's inventing things. He thinks that these are the laws of the physics as he envisages them. But we don't know what happens inside black holes. We don't know what happens at the sub-microscopic level. People sometimes say that the Planck length is an ultimate barrier to us controlling the universe. But that's not at all true. The Planck length, 10 to the minus 35 meters or whatever it is, is just the place where our knowledge stops. We don't know what happens below that scale.

[01:16:45]  Bruce: By the way, we had Julian Barbour on this show, and he actually argued against entropy and in favor of his theory of extropy, which I thought was interesting.

[01:16:54]  Unidentified speaker: Because he didn't buy into heat death at all either.

[01:16:57]  Unidentified speaker: Right.

[01:16:59]  Peter: So as long as we can find a way to turn the universe into a quantum computer and simulate everyone who has ever lived or could ever live, then we'll be golden.

[01:17:10]  David: That's another way.

[01:17:12]  Unidentified speaker: Okay.

[01:17:14]  Bruce: So can I ask you about the dark energy? I call it the dark energy model. Maybe that's a bad thing to call it. But here's the quote from The Beginning of Infinity, Depending on what dark energy turns out to be, it may well be possible to harness in the distant future to provide energy for knowledge creation to continue forever.

[01:17:32]  Unidentified speaker: So now you kind of already mentioned this.

[01:17:34]  Bruce: So but I wanted to kind of bring this out. The Omega Point theory is a single well-developed falsifiable theory because it's so specific, right? It's hard to vary.

[01:17:45]  Unidentified speaker: Yes.

[01:17:46]  Bruce: What I'm calling the dark energy model, it seems like it's more like the hope of a future theory. And you've kind of now explained that it's almost more like you're just saying, look, it's, I don't know what the actual answer is. I just know there's nothing barring us from doing it that we know of at this time.

[01:18:03]  Unidentified speaker: Is that correct?

[01:18:05]  David: So our knowledge of cosmology has decreased since 1997. You know, there's now, we now have discovered a lot more things that affect cosmology than we knew existed before, such as dark energy, especially, but also dark matter.

[01:18:24]  Unidentified speaker: Yes.

[01:18:25]  David: We don't know what these are. We don't know the laws of physics that govern them. It could be that these are the very things that will allow computation to go on forever. So the making a theory about something that depends on things that we don't know is going to always going to be inherently limited. If you make it only out of things that we do know, then it's inherently limited in a different way. But the thing.

[01:19:17]  David: We can take as a fixed point in our theorizing is if we have a hard-to-vary theory about that something is so, like the speed of light, you can say we're not going to be able to exceed the speed of light. Maybe we will, but that will require new physics. With Tipler's old omega point theory, it also required that once we get down to quantum gravity densities, there will be a way of manipulating matter at those densities to make computers.

[01:19:54]  Unidentified speaker: Right.

[01:19:54]  David: There is no theory of that.

[01:19:56]  Unidentified speaker: Right.

[01:19:57]  David: Tipler just assumed it. I think it's a very natural assumption to make. But it's not that we have a theory of that. And it's the same with all these things, with all these theories of the far future. By the way, if we can harness processes at the Planck density, then we may not have to manipulate the whole universe. We can just go down into ever more dense matter short of infinity. We can go down to arbitrary densities, which we know can exist because they existed at the Big Bang.

[01:20:37]  Unidentified speaker: Okay.

[01:20:40]  Bruce: So just to clarify one thing that you just said, getting back to heat death just for a second, let's pretend for a moment that heat death was in fact the correct cosmology. Did I understand you correctly that that would violate the principle of optimism at that point?

[01:20:57]  Unidentified speaker: Yes.

[01:20:58]  Unidentified speaker: Okay.

[01:20:58]  Unidentified speaker: Okay.

[01:20:59]  Unidentified speaker: Just making sure.

[01:20:59]  Bruce: I thought that's what you said, but I was trying to make sure I didn't miss that. Now, Freeman Dyson came up with a cosmology that at least seems a little bit similar to the dark energy model that you brought up. Again, this is totally outside of my area of expertise, so I don't know much about this. But the idea was that you would continue to let the universe cool down, and then you would store energy, and then as long as the universe keeps cooling, you can always just spend half the energy, wait for a long period of time for it to cool down, then you can spend another half the energy, and in theory, supposedly under this model, you could have infinite computation because you could keep life around forever. I don't know how similar that is to the dark energy model you were suggesting in Beginning of Infinity, but it at least shares this idea that the computation is slowing down.

[01:21:53]  David: So again, I think Tipler found, and I've forgotten what it is now, but I think Tipler found a very big flaw in that theory.

[01:22:03]  Bruce: Oh, I was about to actually, I don't know if this is from Tipler, but the main flaw that I had heard with it was that as, so there are quantum events, there's improbable quantum events that take place. And even in Fabric of Reality, you talk about how the other universes include a tiny number of universes in which the butterfly has spontaneously changed into an accidental rearrangement of its atoms, or the sun has exploded because all its atoms bounce towards the nuclear reaction at its core or something like that, right? As you start to slow down in the Dyson and maybe arguably the dark-energy model, eventually these spontaneous weird quantum events would dominate everything and it would make it so that there was no substrate in which you could build a computer.

[01:22:53]  Unidentified speaker: Is that what you were thinking of?

[01:22:54]  Bruce: That's the one I had written down, but I don't know if that was what you were thinking of.

[01:22:57]  David: So I don't think that was Tipler's objection either. I can't remember what it was, but it wasn't that. Now, with quantum things, we know that's false in principle because we know that quantum... Well, we think we know that quantum error correction is possible. So even if there are quantum processes that cause noise, we think that it's always possible to reduce that using quantum error correction, which is different from classical error correction. Anyway, the thing that was just announced just now claimed to have passed the threshold for error correction so that computation can take place, not only can take place despite the build up of errors, but this can be done scalably. So there's no limit to how large a quantum computer you could build. And that's the kind of thing that would also have to be done if we were trying to make the whole universe into a quantum computer, or else dive into a black hole and make that a quantum computer or whatever.

[01:24:10]  Unidentified speaker: Okay.

[01:24:14]  Bruce: I will have to look that up because I had not heard about that as far as the quantum error correction. Wouldn't that eventually though cause a problem with just the substrate itself? If you have to think about how is computation slowing down, wouldn't you eventually just have that your substrate did weird stuff? Or are we just dealing with the computer in quantum wave functions that's just entirely outside of worrying about what the substructure is?

[01:24:42]  David: Well, so in these extreme situations, the only physical objects are gravity.

[01:24:52]  Unidentified speaker: Okay, okay, I'm with you.

[01:24:53]  Unidentified speaker: That actually answers my question.

[01:24:55]  Bruce: Yeah, I mean, I could go to my probability questions, but why don't I let Peter go back to finish his questions first, and then we'll see if we have time. This is exactly, I mean, I've had these burning questions I've wanted to ask David for forever, ever since I read his book.

[01:25:09]  Unidentified speaker: Okay.

[01:25:10]  Unidentified speaker: Okay.

[01:25:11]  Peter: Is it okay if we keep going a little bit, David?

[01:25:13]  Unidentified speaker: Yeah.

[01:25:14]  Unidentified speaker: Okay.

[01:25:17]  Peter: Three worlds. So one of the things that I love about your philosophy is that you take the reality of abstractions very, very seriously. That was a real a-ha moment for me when I started thinking about something like, human ideas is more like a, almost like something governed by the laws of physics or something.

[01:25:44]  Unidentified speaker: I'm not quite thinking of the right language here.

[01:25:48]  Peter: But these abstractions include our ideas and explanations that have significant causal power in the universe. Human knowledge is almost like a force of nature that could one day dominate the universe, such as in Tipler's Omega Point. I'm curious on your take on Karl Popper's three worlds framework. For our listeners, obviously you know this, but Karl Popper divides the worlds, divides reality into three worlds, the physical reality of rocks, trees, stars, world one, world two, which would be subjective, conscious experience or what we feel privately. And the world three, which is the world of objective knowledge or anything that can be transmitted by a meme, including science, art, language, et cetera. It truthfully, it makes a heck of a lot of sense to me, but I've heard in various places that this is not a part of Popper's worldview that you subscribe to. And I wasn't exactly sure why. What is the difference between how you see the reality of abstractions and Popper's three worlds?

[01:27:02]  David: Well, I can't speak for Popper. So, you know, I can't say he thinks so-and-so, and I think so-and-so. I would just, I would rather just say what I think, and then you can decide whether it's the same or different or contradicts or whatever Popper.

[01:27:21]  Unidentified speaker: Fair enough.

[01:27:22]  David: So, I, I think Popper basically thinks that worlds two and three are created by humans, and that world one sort of creates humans, and then humans make ideas. Now, I think that there's a, there's a difference between ideas that are instantiated somewhere and ideas in the abstract.

[01:27:50]  Unidentified speaker: So, ideas that are genuinely abstract.

[01:27:52]  David: I think that all the integers exist, even though almost none of them are ever going to be instantiated. Well, unless, you know, after the omega point or towards the omega point or something, they eventually will. But at any finite point, almost none of them have been instantiated, because there's only a finite number of them instantiated and an infinite number that haven't. But I think that it makes sense to talk about the properties of the ones that haven't been instantiated. And that takes us to the reality of counterfactuals, of things that would be true if the laws of physics were different. I think it makes sense to speak of those things. And in fact, I think it doesn't make sense not to speak of them. I think unless we can speak reasonably about the things that can't happen, the things that don't happen, then we also can't speak reasonably about the things that do happen. Otherwise, you know, we're, again, we're losing...

[01:29:14]  David: If you say the things, if you say it's meaningless to talk about the things that didn't happen, then it's meaningless to say that Einstein created the theory of relativity because it was always going to happen. And nothing that didn't have relativity in it is real. But I think that's wrong. I think it sabotages all explanation ultimately. Really, all explanation has got counterfactuals in it somewhere.

[01:29:51]  David: So, and also Popper, I think, is a bit too... Now I am putting words in his mouth. And I think he's a bit too anthropocentric.

[01:30:08]  David: I think that scientific ideas, for example, can be objective, even if there's no scientific community, even before anybody has transmitted the idea to anyone else. And even if they die before they ever mention it to someone else, I think that idea was real and had, in the case where it was in someone's mind, it had a real physical effect because the brain is a physical object and the ideas in it have effects on it. And, you know, somebody might have a wonderful new theory of dark energy and can be all excited and release adrenaline and that adrenaline causes a heart attack and the person dies and no one else ever hears of that theory. In fact, could be that nobody ever hears about it because the course that science will take after that will not pass through his theory. It will bypass it and go to the next theory. So his theory will never be known to anyone but him. And I think that it makes sense to say that it was known to him and that it was a scientific advance. It was genuine knowledge.

[01:31:26]  Unidentified speaker: He genuinely created it.

[01:31:29]  Bruce: So if Einstein is on his way to go publish his article and he dies on the way and everything gets lost, the theory of relativity is still knowledge, even though it never escaped outside of his brain, let's say.

[01:31:42]  Unidentified speaker: Or not for long.

[01:31:45]  Unidentified speaker: Yes.

[01:31:45]  Unidentified speaker: Good.

[01:31:47]  Unidentified speaker: OK.

[01:31:47]  Unidentified speaker: Well, that clarifies things.

[01:31:51]  Unidentified speaker: Thank you.

[01:31:52]  Unidentified speaker: Hitting all the bases, bases here.

[01:31:55]  Unidentified speaker: Consciousness.

[01:31:57]  Peter: So as I understand you, consciousness will ultimately be described by an algorithm.

[01:32:02]  Unidentified speaker: So in this form of dual, can I just say, I say something wrong already.

[01:32:06]  Unidentified speaker: OK.

[01:32:08]  David: Well, again, it's my fault.

[01:32:10]  Unidentified speaker: OK.

[01:32:10]  David: I should better say a program, a computer program, a program algorithm has a particular meaning for computer scientists and mathematicians.

[01:32:21]  Unidentified speaker: Oh, fair enough.

[01:32:21]  David: A program that terminates with an answer.

[01:32:25]  Unidentified speaker: Fair enough.

[01:32:26]  David: OK.

[01:32:27]  Unidentified speaker: OK.

[01:32:27]  David: That's really very different from what brains do. The thought process doesn't terminate.

[01:32:33]  Unidentified speaker: It's an open ended process.

[01:32:34]  David: It may produce answers as it goes along, but it may not. Again, you know, Einstein could have spent the last several weeks of his life not producing any output, but he was still thinking, it's still conscious and so on. So consciousness is a running program, not necessarily an algorithm.

[01:32:57]  Unidentified speaker: OK.

[01:32:58]  Unidentified speaker: OK.

[01:33:00]  Peter: So in this form of dualism, our minds are something more like software running on hardware.

[01:33:06]  Unidentified speaker: So is that fair?

[01:33:07]  Peter: It's kind of a program, software program.

[01:33:10]  David: [wording uncertain] words, calling it dualism.

[01:33:13]  Unidentified speaker: But OK, OK, OK.

[01:33:15]  Unidentified speaker: I said this form, unique form.

[01:33:17]  Peter: OK, so once we understand this algorithm, AGI or artificial humans will be, I assume, relatively easy to create.

[01:33:27]  Unidentified speaker: Yes.

[01:33:28]  Peter: Alternatives to this view include Roger Penrose's microtubule, tubules, wherever you say that, or Daniel Dennett's materialism, Philip Goff's panpsychism, Lee Cronin's assembly theory, or just the view held by probably the overwhelming majority of humans who have ever existed, which is that humans have souls that just can't be understood analytically. Your ideas make the most sense to me, but I'm just curious, how do you know, fallibly with all the critical rationalist caveats, that you are right and all these other great thinkers are not?

[01:34:08]  David: Well, they don't all make the same mistake. But I think I would have criticisms of all those things. I mean, some of them are appeal to the supernatural, which I have a general criticism of. Some of them are just frills on top of just the physicalist explanation. I think that minds are running computer programs, which have of a certain type, and we don't know how to characterize that type. If we could characterize it, we could program it. But there is an objective difference between programs that are and are not conscious. And this difference is qualitative in the sense that we discussed earlier, that you could degrade the hardware on which the program is running until it could no longer execute its characteristic function that makes it a mind. But that doesn't change the fact that there is an objective difference between minds and non-minds. Just like there is an objective difference between universal computers and non-universal computers.

[01:35:38]  Unidentified speaker: Thank you.

[01:35:39]  Bruce: So I'm not a very big fan of panpsychism.

[01:35:43]  Unidentified speaker: In fact, I kind of feel rankled every time it comes up.

[01:35:47]  Bruce: But it sure seems like it's really popular right now. The problem that I've felt like I've seen with panpsychism is that it… Obviously, panpsychism could mean a lot of different things.

[01:35:59]  Unidentified speaker: So let me be more specific.

[01:36:01]  Bruce: I'm talking about David Chalmers, who may or may not be considered panpsychist, but he certainly raised it as a possibility, or Philip Goff, someone who's trying to pose it as a scientific theory rather than as a supernatural theory. But it still seems like panpsychism bumps into this problem where ultimately there's some sort of atom that can't be explained that is called consciousness.

[01:36:27]  Unidentified speaker: Yeah.

[01:36:28]  Bruce: Oh, you agree with me on that?

[01:36:29]  Unidentified speaker: Yes.

[01:36:30]  Unidentified speaker: Okay.

[01:36:32]  Bruce: So in essence, they are saying there's a boundary that we cannot explain past.

[01:36:37]  Unidentified speaker: Yes.

[01:36:38]  David: And I sympathize with the motivation that I think may be behind some of the forms of panpsychism. Namely, most people are repelled by the idea that consciousness doesn't exist, or that free will doesn't exist, or that thought doesn't exist, that all that's going on is just some atoms. And they want to say, no, I'm different from this skull that contains no brain, with, you know, Yorick's skull. I'm different from it.

[01:37:27]  David: Then the anti-free will person says to them, yes, but there's nothing in your skull that isn't atoms. Just like, you know, the skull is made of atoms, the brain is made of atoms. There's nothing there apart from the atoms, and they all obey the same laws. So people who feel vulnerable to that argument, some of them, I think, find a way out by saying, yes, the atoms are conscious too, just a lot less than me.

[01:38:03]  Unidentified speaker: Right, right.

[01:38:06]  Bruce: I kind of have the same perception that that's what they're trying to do, right?

[01:38:12]  Unidentified speaker: Yeah.

[01:38:13]  Unidentified speaker: Well, I've got one more.

[01:38:15]  Unidentified speaker: So children, another way that you have, I would say, influenced me, my life is my relationship with my sons.

[01:38:27]  Peter: Let's just say my relationship with my son has improved, I think, since I've looked into your philosophical ideas regarding a non-coercive approach to raising children, which I will say that I implement fallibly, but it has influenced me. But I will say that I'm not exactly a true believer in taking children seriously either, as much as I'm very sympathetic to it. Maybe I just need to see more children raised this way. I just don't have the experience of seeing that. A vastly more mainstream framework for thinking about parenting that I see all the time is psychologist Diana Baumrind's Four Styles of Parenting. Maybe you've heard of this, where you have authoritative, authoritarian, permissive, or neglectful. And I've heard, at least credibly claimed, that there is a tremendous amount of evidence that the authoritative approach leads to the best outcomes. Someone said that there's more evidence for this than anything else in psychology. That's what at least one person claimed. I suspect that you would be skeptical of this kind of evidence based on psychological studies. I do not read you as saying that you look at the meta studies, and that's how you decided that taking children seriously was right.

[01:40:03]  Unidentified speaker: That's not how I understand you.

[01:40:05]  Peter: So what do you think that in parenting or anything else for that matter, would you say that we should pursue what is philosophically coherent rather than what the studies say? I mean, is that a better approach?

[01:40:24]  David: So first of all, the issue is a philosophical one. In particular, it's moral and it's epistemological.

[01:40:36]  David: And neither of those issues can be settled by any experiment or any evidence. Experiment and evidence are relevant, but not in settling the moral and philosophical issues.

[01:40:57]  David: So that's where I have to begin.

[01:41:03]  David: I don't believe a study that says that if you beat children, it will harm them. And I don't believe a study that says if you beat children, it will help them. I think that children are people, and how people deal with each other is a matter of moral philosophy. And moral philosophy is shaped by epistemology, because children in particular are... their lives are dominated by learning things, and learning things, the theory of that is... the best theory of that that we have is Popper's theory of problems and conjectures and criticism and so on. And therefore, things that suppress that rational and creative process are going to impede the growth of knowledge, which is going to have moral implications. So those are the kind of levels on which I would want people to think about children, but not just children. I mean, exactly the same thing applies to politics. You know, it's no good having doing a study that says that this or that conception of human rights is better than another. You know, if, say, there's a controversy about whether copyright should be a human right, whether you should be deemed to own the information that you produce, or whether you should not be deemed that information wants to be free, and therefore copyright should not exist, copyright law should not exist, or something in between, like we have any of these things. This cannot be settled by experiment. It's, again, it's a matter of philosophy.

[01:43:23]  David: And if somebody shows that the countries that have a certain copyright law make more economic progress than the ones that don't, it has the usual problem of doing experiments on humans. You don't know that you're looking at something that has billions of factors affecting the outcome, and you're picking one, and choosing your policy, depending on that one. So if you want to refute the idea that the outcome was caused by a different factor, then you've got to control for that factor, which means that you've got to have a larger sample. And if there are 200 countries in the world with different copyright laws, then there's not much you can do. You know, if you want to control for three factors, and you have only 10 countries in your sample, then you already need to have a thousand before you can control for everything. And if there's a billion factors, well, it's just hopeless. What you have to have is an explanatory theory, and that theory will be, in this case, it'll be about epistemology mostly. Well, the morality will come in to it. In other things, like, you know, should you beat your wife, morality will be more important than epistemology, though again, both will be relevant. But experiment will not be relevant.

[01:45:17]  Peter: It's interesting that they, yeah, I mean, I think probably a lot of people kind of know this on some level. I mean, you wouldn't, like, perform a psychological experiment about wife beating, would you? I mean, that would be, I mean, I can imagine a situation where you couldn't.

[01:45:34]  Unidentified speaker: Well, anyway, Bruce, thank you for that, David.

[01:45:38]  Peter: Bruce, why don't you?

[01:45:41]  Bruce: So on the Increments podcast, you did an interview with them and you talked about probability. And I promise I will not completely rehash everything that they went through. And I actually really liked the answers that you gave to their questions and challenges to you. I, correct me if I'm misinterpreting you here, but I definitely have understood you as saying that you don't believe that probability exists. Is that an accurate or inaccurate statement?

[01:46:08]  David: Stochastic processes don't exist.

[01:46:10]  Unidentified speaker: Stochastic processes don't exist.

[01:46:12]  Unidentified speaker: Okay.

[01:46:13]  David: In other words, things which are physically random don't exist.

[01:46:17]  Bruce: So here's a quote from you on the podcast where you said for the roles of a die, it is, this is almost a quote. I had to adjust it a little bit because I'm taking it out of context. For the roles of a die, it is not that it is random. It is that it be fair to all the players in that there is no algorithm that will enable them to unfairly win the game.

[01:46:42]  Unidentified speaker: So everyone is on equal footing.

[01:46:44]  Bruce: And it's as long as it's unpredictable, it doesn't matter whether you use the digits of pi or the rolling of a die. So both have the right property and the right properties are that they produce a number from, in this case, one to six, roughly equally. So there is no way to predict it. So maybe I was wrong to say probability, but you're saying that that is not random. And I assume you mean random in the sense of stochasticity here.

[01:47:12]  Unidentified speaker: Okay.

[01:47:14]  Bruce: So now it's interesting, again, to ask my questions, I need to do a little bit of a setup to give you some background information. It's interesting that the word probable, if you go back far enough, this is going back quite far, actually had a somewhat different original meaning. At least according to the Oxford dictionary, me looking it up in the etymology in it, it claims that in the Old French, it came from the Latin probabilis, and it comes from the Latin probare, which means to test or to demonstrate, and is the same root as probe. So presumably, going back far enough, maybe even outside the English language, the original meaning to say this is probably true, this theory is probable, would have meant something way more compatible with critical rationalism. It would be the idea that the theory was probable, probe-able, and therefore meaning that it could be and was severely tested.

[01:48:11]  Unidentified speaker: Yes.

[01:48:12]  Unidentified speaker: Okay.

[01:48:13]  Bruce: Somewhere in there, in Middle English, the word came to mean worthy of belief, which I suspect you would take more issue with. But we might reasonably take that to mean something like worthy of tentatively accepting as the current best explanation due to the fact that we have probed it and it's the only surviving explanation.

[01:48:34]  Unidentified speaker: Okay.

[01:48:34]  Unidentified speaker: Yes.

[01:48:35]  Bruce: So we're okay so far with this.

[01:48:37]  Unidentified speaker: Yes.

[01:48:37]  Bruce: Now, obviously, words change meaning over time or even have multiple different uses all in one language at the same time. If someone were to come to me and they were, let's say English was the second language and they're like, look, I've got this concept and I want to talk about what it is like where you roll a die and you're gambling and there's this process and you can't predict it and it's equally distributed. What would I call that in English language? And I absolutely would have said that's called probability in the English language.

[01:49:15]  Unidentified speaker: Okay.

[01:49:15]  Bruce: Or it was called randomness in the English language and I would have said that. That's isn't what you seem to mean in this case, when you're talking about stochasticity. So I just want you to maybe explain what you are actually conceptually thinking about different than this.

[01:49:32]  Unidentified speaker: Yes.

[01:49:34]  David: What I mean by the die being fair, is that, and the process of rolling it, being fair, is that it is both fair to the players and unpredictable to them. That's all I mean. So where does probability come in? Well, we can't make a model, a mathematical model of being fair to people. Because that's all about their decision process, and whether their process can depend on properties of the die in various ways. So there is a trick that was invented by maybe by Cardano or something in the 16th century or Laplace a bit later, where we say, we can't model it faithfully, but what we can do is we can argue that in making decisions about how to bet, we would make the same decisions if we thought the die and its rolling was a stochastic process. So imagine a model in which the die is random, its behavior is a stochastic process.

[01:51:04]  David: Calculate how you should bet, should you bet on an inside straight or whatever it is. And then we have an argument that that would be the same. The answer would be the same as it would be if we could actually model the players and their decision processes. So, it's useful as an unphysical mathematical model, which we argue is the same. It's the same because it would be equally fair and equally unpredictable if it were stochastic.

[01:51:48]  Bruce: So, why not just call that stochastic then, if it's the same? What's the difference between this fake version of stochasticity and actual stochasticity?

[01:51:58]  David: Well, the difference is that we know the actual laws of physics that govern the die, and they have no randomness in them.

[01:52:06]  Unidentified speaker: They are completely deterministic.

[01:52:09]  Bruce: So, let me ask about that.

[01:52:11]  Unidentified speaker: Let's do a thought experiment.

[01:52:12]  Unidentified speaker: I'm going to roll a die.

[01:52:18]  Bruce: I've always been a little unclear because there's quantum physics, there's this multiverse. Is there going to be an equal proportion of multiverses, each with a version of me that gets every single side of the die? Or is this more chaotic, chaos theory, and there's probably going to be one version of me, but we just can't predict what I'm going to see?

[01:52:41]  David: There's been some literature about whether a coin toss is quantum random or not.

[01:52:48]  Unidentified speaker: Yeah.

[01:52:51]  David: But it doesn't matter from this point of view. I think the chances are the die does divide the multiverse into six approximately equal parts when it's thrown.

[01:53:13]  Unidentified speaker: That makes some sense to me.

[01:53:15]  Unidentified speaker: Okay, go ahead.

[01:53:17]  David: But it wouldn't matter if it weren't. If some of those are not one-sixth of the total, but some of them are one-fifth, and some others are one-seventh, and so on. So long as no one can extract that information, for example, by taking the die and throwing it a thousand times, and then seeing how biased it is, and then putting it back, and then using that. So long as no one has done that, the game is fair. And in real life, even the idealized stochastic die won't come up with the six numbers an equal number of times. That's astronomically unlikely. Like if you throw it a thousand times, that's astronomically unlikely. So what is this property of randomness? Well, I think it ultimately doesn't make sense. It's just a word that we attach to this mathematical model, saying that in this model, we're going to assume it's fair and all that stuff.

[01:54:37]  Bruce: Isn't there like an explanatory component here though? Like, I have an explanation for why a well-weighted six-sided die, if you're using it in certain circumstances, you're not rolling it in sand, you're rolling it on a flat table surface. Doesn't that explanation come into why I have... My best theory is that I will get an equal proportion of roles.

[01:55:02]  David: But you won't get an equal proportion, and your best theory says you won't.

[01:55:10]  David: So that won't do as an explanation.

[01:55:14]  Unidentified speaker: Okay.

[01:55:16]  Unidentified speaker: So, but you will roughly get it, is what you said.

[01:55:21]  David: Ah, but yes.

[01:55:23]  Unidentified speaker: But you may not.

[01:55:24]  David: In other words, you won't get it. So if I buy a computer and I say, does it run Windows? And someone says, well, approximately, that's not good enough. I want it to actually run Windows. And when, as I say in that talk I gave, if somebody goes to a casino and loses his shirt and comes out and says, well, I probably won. That is, I did the thing that causes me to, that would have caused the, sorry, I did a thing that did cause me to have a high probability of winning.

[01:56:11]  Unidentified speaker: But I didn't win, right?

[01:56:12]  David: But I didn't win. So he can't pay his rent with that. That's not referring to anything real.

[01:56:22]  Bruce: So I have kind of in mind here the idea of an expected value. So I have an explanation. You're right that my best theory says that I won't get exactly, but of course, that's what it's saying, right? That is part of what we call probability theory today, right? Whether we agree on what that term exactly means, or not, that's a different question. There is an expected value that means something, right? You even had this idea of someone secretly takes the die and rolls it, right?

[01:56:55]  Unidentified speaker: And then checks.

[01:56:57]  Bruce: In fact, typically, because we have an explanation as to how a weighted die should act when you're rolling it, nobody even feels the need to check it. But if they did, we'd let them do it, because we feel we've got an explanation that would allow them to go and check this and they could severely test it. And if they did enough rolls, we would expect them to get a result that's consistent with a roughly equal distribution of every single outcome.

[01:57:26]  Unidentified speaker: Okay.

[01:57:27]  Bruce: So you're not necessarily denying an expected value here.

[01:57:31]  Unidentified speaker: Is that correct?

[01:57:34]  David: No, I'm not. There is such a thing as expecting something. Although note that if they got exactly equal numbers, you would think that something's off.

[01:57:47]  Unidentified speaker: You're right.

[01:57:48]  David: But you'd know there was something off.

[01:57:50]  Unidentified speaker: Right.

[01:57:51]  Bruce: If it was across a thousand rolls or whatever, right?

[01:57:56]  Unidentified speaker: Okay.

[01:58:00]  Bruce: So I think where I'm trying to go with this here is, there's this idea that we call this probability.

[01:58:08]  Unidentified speaker: Okay.

[01:58:08]  Bruce: Or we call it stochasticity. But you're saying it's not stochasticity. I have to come up with a model to try to explain what I'm talking about, and the model might be wrong. But let's go with the six-sided die, and let's go with the assumption that there's an equal proportion of me across the multiverse.

[01:58:29]  Unidentified speaker: Okay.

[01:58:29]  Bruce: Because it's a well-weighted die. And it's been arranged so that it's actually quantum events that determine which one I'm going to see. Me being whichever one then becomes differentiated.

[01:58:44]  Unidentified speaker: Okay.

[01:58:45]  Bruce: From my point of view, isn't that exactly what we mean by stochastic event? Granted, at the level of the multiverse, it's not.

[01:58:54]  Unidentified speaker: It's a purely deterministic event.

[01:58:57]  Bruce: But isn't that what we mean by stochasticity to begin with in most cases?

[01:59:03]  David: Well, we may mean something that's impossible. So, you know, people may have the wrong idea about how something works.

[01:59:12]  Unidentified speaker: They may have the wrong idea.

[01:59:13]  Unidentified speaker: Sure.

[01:59:15]  Bruce: What is that idea that would, if someone has the wrong idea, I guess this is what I'm trying to get at. If someone has the wrong idea, what does it actually mean?

[01:59:22]  Unidentified speaker: The thing that they mean that is wrong.

[01:59:24]  David: It's what you said at the beginning. What it used to mean makes much more sense. What it used to mean has to do with testing and explanations.

[01:59:42]  David: This concept of probability came in to everyday life from game theory, and then later from mathematics, and later from physics. And I think the authority of those fields has caused people to think that there's nothing problematic about the concept of probability, sorry, about the concept of stochastic probability. Just like in the 19th century, they didn't think there was anything probability, anything. I have a [restart wording uncertain] problematic about thinking that truth was the same thing as provability. And Hilbert noticed that they're not the same, and the idea that they are the same needs proving. And so he put up this challenge, and Gödel and Turing proved that there are truths that are unprovable. But in everyday life, we often mix the concepts. In fact, I think, I can't remember now, I think one of you may have done it during this conversation.

[02:01:15]  David: Oh no, you didn't say, how can you prove that? You said, how do you know that? But mathematicians sharply distinguish between a mathematical proposition being true, which if it makes sense at all, then it's either true or false. And it being provable, which we now know, almost none of the true mathematical propositions are in fact provable.

[02:01:45]  Unidentified speaker: And that's provable.

[02:01:48]  David: So I'm just saying that the everyday concept, an everyday concept can simply not match reality, but still be useful for some purposes. It won't kill you if you make that mistake, usually.

[02:02:04]  Bruce: So let me go back to my quantum die example here, right?

[02:02:08]  Bruce: Where let's say we even make it so it's an actual quantum event, so that we're making sure we're splitting across the multiverse across six different options, okay?

[02:02:18]  Bruce: Then we label one, two, three, four, five, six.

[02:02:21]  Unidentified speaker: Yeah.

[02:02:21]  Unidentified speaker: Okay.

[02:02:22]  Bruce: From my point of view, I'm going to see one of them come up, and I would have called that a stochastic event.

[02:02:29]  Bruce: Now, I understand what you're saying.

[02:02:31]  Bruce: I'm maybe using the term in a far more specific way than was originally conceived that came with some baggage that we don't want.

[02:02:39]  Bruce: Is that, do I understand you correctly on that?

[02:02:41]  Unidentified speaker: Yes.

[02:02:41]  David: So if it really were stochastic, that would mean that there was only one of you, and that one of you ended up in one of the worlds, and then the other six...

[02:02:51]  Unidentified speaker: Don't exist.

[02:02:52]  Bruce: Okay, so for you, the word stochasticity, the reason why it doesn't exist is because it is a single universe type of thing which isn't true, because there's a multiverse.

[02:03:04]  David: Yes, and because the laws are deterministic. So I can imagine indeterministic laws and laws of motion that are stochastic. At least I can with an effort.

[02:03:22]  Bruce: Okay, now I have a follow on question for that, now that I've got that straight in my mind.

[02:03:28]  Bruce: So we have this thing that we call probability theory.

[02:03:32]  Bruce: Okay, and you just explained that it actually does at least make somewhat sense.

[02:03:38]  Bruce: I'm going to ask you about how much sense it makes in terms of making bets when you're gambling with dice, or for that matter with cards.

[02:03:48]  Bruce: There's the fact that you shuffle it, but the cards once they're shuffled, they're in a certain specific order.

[02:03:53]  Unidentified speaker: They're not like a die anymore, right?

[02:03:54]  Unidentified speaker: Yeah.

[02:03:56]  Bruce: And let's say that I'm trying to write the program that beat all of the Texas hold ’em professionals, right?

[02:04:08]  Bruce: I'm the one who's going to write this AI program that can beat them.

[02:04:12]  Bruce: And of course, they're going to use probability theory to work this out.

[02:04:16]  Bruce: They're going to use probability theory, expected values, et cetera.

[02:04:21]  Unidentified speaker: Now, is it just that from the point of view that you're explaining, does probability theory perfectly fit exactly what would make sense?

[02:04:33]  Bruce: There's no better theory available?

[02:04:36]  Bruce: Or is it just an approximate theory and there's a forthcoming better theory, let's say a hypothetical constructor theory or probability or something like that, that is going to replace probability theory because it's incorrect?

[02:04:50]  Unidentified speaker: Or is it actually the correct theory is just misnamed because we put the word probability on it?

[02:04:57]  David: By the way, there is a constructor theory of probability produced by Chiara Marletto. But it doesn't affect what to do when you're playing a game of poker or a game of dice.

[02:05:12]  Unidentified speaker: Okay.

[02:05:14]  David: In real life, things will not model stochastic processes perfectly. So in real life, it won't be one sixth probability. In real life, it will depend on which seat you're sitting in. So it will favor one person rather than another person. So but in terms of what kind of mathematics we use to choose how to bet, which doesn't depend on any of those things, probability theory is going to be the right theory. The extent to which it makes sense to talk about expecting a certain outcome when, and saying that that was the right expectation to have, even if it wasn't borne out in real life.

[02:06:14]  Unidentified speaker: Right.

[02:06:15]  David: What that means? Well, basically, I've written a paper about this, called The Logic of Experimental Testing.

[02:06:28]  Bruce: I've read the paper multiple times.

[02:06:30]  Unidentified speaker: Yeah, excellent, excellent paper.

[02:06:33]  Unidentified speaker: Right.

[02:06:34]  David: Well, in that case, maybe I'm wrong that the answer is in there. But the answer follows from what's in there.

[02:06:40]  Unidentified speaker: Okay.

[02:06:43]  Unidentified speaker: How do I say this?

[02:06:44]  Bruce: Should it not be called probability theory?

[02:06:47]  Bruce: Like, the theory is actually valid under the right circumstances is what you're saying.

[02:06:52]  Bruce: Should it not be called probability theory, then?

[02:06:55]  David: There's a mathematical theory of probability.

[02:06:57]  Unidentified speaker: Yeah.

[02:06:58]  David: Which doesn't identify probabilities with outcomes or stochastic processes or any kind of physics. It's just a theory about certain numbers attached to certain abstract objects.

[02:07:11]  Unidentified speaker: Okay.

[02:07:12]  David: So that's, the mathematicians call that the theory of probability.

[02:07:16]  Unidentified speaker: I see.

[02:07:16]  Bruce: Because it's a mathematical theory, it's got nothing to do with the underlying physics is what you're saying.

[02:07:21]  Unidentified speaker: Yes.

[02:07:22]  David: And they will get angry with you if you say that the probability is about something physical. So you should say it can be applied approximately to some physical things.

[02:07:39]  Unidentified speaker: Okay.

[02:07:40]  Bruce: Now, I have one last question about this.

[02:07:43]  Bruce: Obviously, a lot of what I've been asking about, maybe is channeling Popper's propensity theory of probability.

[02:07:51]  Unidentified speaker: Right.

[02:07:53]  Bruce: Let me try to explain what I mean here in case there's people in the audience who don't know what I'm talking about.

[02:07:59]  Bruce: So there's been very various different philosophical theories about how to understand probability theory.

[02:08:06]  Bruce: And Popper came up with one called the propensity theory of probability.

[02:08:09]  Bruce: And I'm not sure I'm an expert in it, so I may explain it somewhat wrong.

[02:08:13]  Bruce: But he would have explained the dice game that we're talking about.

[02:08:17]  Bruce: Now, he wouldn't have had this idea of a multiverse or not.

[02:08:20]  Bruce: I'm not even sure he would have considered that in his propensity theory.

[02:08:25]  Bruce: But he would have understood this in terms of that when you roll this dice, that there are laws of physics that are going to have a propensity, given the right circumstance.

[02:08:37]  Bruce: He specifically talks about rolling on the table, which is why I use that as my example versus rolling in sand, he says.

[02:08:44]  Unidentified speaker: Can you comment on that?

[02:08:45]  Bruce: It seems to me like that underlying idea seems really correct to me, that there is a certain propensity that we're talking about.

[02:08:54]  Bruce: You're right that it may not actually be one in six, right?

[02:08:58]  Bruce: And Popper wouldn't be claiming that we would know for sure it was one in six.

[02:09:02]  Bruce: But he would be claiming that there is some sort of propensity for that die to come up in a certain way.

[02:09:06]  Unidentified speaker: Okay.

[02:09:07]  Unidentified speaker: Can you comment first of all on that?

[02:09:08]  Bruce: And to what degree you agree or disagree with the propensity theory of probability?

[02:09:14]  David: I think the propensity theory of probability is the philosophical theory, which would be the appropriate one to describe stochastic processes if they existed. But as far as we know, they do not exist. And therefore, far from being a general property of physical objects, that they have various propensities to do various things, propensities are only relevant to physics in certain specialized situations, such as gambling. In other situations, in quantum theory, the axioms of probability theory aren't even obeyed. The relative probability of A given B, that kind of thing, just don't hold in...

[02:10:07]  Bruce: Can you give us an example of that, or is that something that's going to be too complicated?

[02:10:11]  Unidentified speaker: But a layman's example of that?

[02:10:15]  David: If you have an interferometer, where there's a particle that can go in one of two ways, and then later each of them goes through another process, which itself goes through one of two ways, and they are perfectly 50-50, both of them. Then according to probability theory, there are four possible outcomes, and they all have the same probability, namely one-quarter.

[02:10:45]  Unidentified speaker: Right.

[02:10:46]  David: The outcomes are 0-0, 0-1, 1-0, and 1-1. In an interferometer, that just isn't true. It could be that only two of those, for example, it could be that only two of those outcomes ever happen. Even though it is true that the probability of the first one is 50-50, the probability of the second one is also 50-50, and so on.

[02:11:12]  Bruce: Is that because of the interference pattern, the interference pattern?

[02:11:17]  David: Yes, because the outcomes interfere with each other.

[02:11:21]  Unidentified speaker: Right.

[02:11:22]  Bruce: Which that makes perfect sense to me, that you're right, that would not...

[02:11:26]  Bruce: It seems like Chiara does use that as an example in her book, actually.

[02:11:30]  Unidentified speaker: So that's like ringing a bell.

[02:11:32]  David: But most physical process, the overwhelming majority of physical processes are like that. They are not like dealing cards or throwing a die.

[02:11:45]  Bruce: I wasn't going to ask this one, but I'm going to try to go ahead and ask it anyhow, and we'll make this my final question.

[02:11:54]  Bruce: So I think I understand where you're coming from now, that you're understanding the word stochasticity as being specifically linked to if there was a single universe instead of a multiverse.

[02:12:08]  Bruce: Let's now talk about use or possibly, arguably, abuse of probability theory when applied to something that's got nothing to do with gambling.

[02:12:18]  Bruce: So I'm going to use probability theory to, let's say, work out a robot arm, like they use probabilistic robots, there's a textbook called probabilistic robots, where they're using it to try to figure out where the robot can figure out where its arm is, and so it knows how to move it, or where it is in the room, or something along those lines.

[02:12:41]  Bruce: Or maybe we can even go crazier, using probability theory to try to figure out the probability that given certain factors, I'm going to have cancer or something along those lines.

[02:12:52]  Unidentified speaker: Okay.

[02:12:53]  Bruce: I definitely think these are nowhere near as need, and that was why I was trying to stick with examples that were specifically gambling examples.

[02:13:03]  Bruce: And yet, you can't say that these examples don't work.

[02:13:08]  Bruce: Particularly the probabilistic robots, it actually works.

[02:13:11]  Bruce: You use probability theory, you know that you treat the fact that the robot sensors aren't exactly correct as probabilistic noise, and it will actually self-correct over time through perceptions.

[02:13:25]  Unidentified speaker: What do we call that?

[02:13:26]  Bruce: Like, if that's not stochasticity, if that's still an appropriate use of probability theory, is it appropriate if it works somewhat?

[02:13:35]  David: So the theory of errors is also one, was also one of the earliest applications of the probability calculus, to the theory of error. And there is a theory of errors which uses the theory of prob… the mathematical theory of probability. And again, like with gambling, there has to be an argument for why…

[02:14:02]  Unidentified speaker: An explanation.

[02:14:03]  David: Yes, an explanation for why we expect this model of stochastic processes, which is not the case in the real world, why we expect that to be a good approximation to the real world in the situation with… So in the situation where we have errors, it may make sense to say that a certain thing is equally likely to be wrong on the left or wrong on the right, and only change that when we find evidence of the contrary. Right. So, in fact, I think that use happened before the gambling use historically. But again, if the physical situation doesn't match the mathematics, then it will give a wrong answer. And people will make mistakes, like saying, well, it's worked a thousand times, therefore, the probability of it not working is approximately one in a thousand, or less than one in a thousand. So we expect it to work next time, and that is just invalid. And that's the sort of thing that gets people killed.

[02:15:42]  Bruce: I agree that the way you just gave that is it's absolutely invalid, because it ultimately does come down to whether you have the right explanation or not.

[02:15:50]  Bruce: Like on the Increments podcast, they use the example of the hospital and the hospital tries to use past data.

[02:15:57]  Bruce: Nobody in their right mind would use that model in 2020 when COVID comes out, right?

[02:16:03]  Bruce: You absolutely have an explanation for why it would make no sense to treat your past model as just probabilities as to how many people are going to be coming to the hospital.

[02:16:14]  David: People have used it for COVID when they advocate some kind of policy like lockdowns, not lockdowns, vaccination, not vaccination, that kind of thing. Then they say, well, let's look at 200 countries which had lockdowns and see which of them had a higher level of deaths from COVID. And that's completely without an explanation, that is just meaningless.

[02:16:48]  David: We know that whether you die of COVID depends on thousands of factors. And to take one of them and use the statistics of that, or take two of them, simply isn't valid. If you have an explanation, then the conclusion is as good as your explanation. If you have a very good explanation, then the probabilities that appear in your explanation will be useful numbers.

[02:17:21]  Unidentified speaker: Yeah.

[02:17:23]  Bruce: So I know I just said that was my last question, but would it be okay if I asked one more based on what you just said?

[02:17:29]  Unidentified speaker: Yeah.

[02:17:30]  Bruce: So let's go ahead and I know this is a politically charged subject, but let's talk about COVID and making a decision whether to wear a mask or not.

[02:17:44]  Bruce: For the sake of argument, we're not going to go to whether you should mandate masks or not.

[02:17:48]  Bruce: We will just talk about whether it's a good idea to wear masks or not.

[02:17:53]  Bruce: Now, Nicholas Taleb argued at the time, we knew very little at the time, that we have a good explanation for why we should wear masks and why that would cut down on transmission of COVID.

[02:18:08]  Bruce: I have not, this isn't something that's very interesting to me, so I have not followed up on this, but I've definitely heard later on challenges whether that actually made sense or not.

[02:18:18]  Bruce: But at the time, that's our explanation.

[02:18:20]  Bruce: It could have been a correct explanation, it could have been an incorrect explanation.

[02:18:25]  Bruce: What's the right way to actually test an explanation like this in the real world, given that you can't do a controlled experiment?

[02:18:33]  Bruce: It's either in the case of COVID, maybe arguably immoral to try to test it.

[02:18:39]  Bruce: I guess you could test it on animals.

[02:18:44]  Bruce: Like you said, you have an explanation and you could treat it as probability, but that's only going to work if your explanation happens to be right.

[02:18:53]  Unidentified speaker: Okay?

[02:18:54]  Bruce: Then you can treat it as probability.

[02:18:56]  Bruce: And you don't actually know, you don't get to know that up front.

[02:18:59]  Unidentified speaker: You don't get to know that right now.

[02:19:01]  Bruce: What's the right way to actually go about trying to figure this out?

[02:19:05]  David: As in the case of COVID, as I said in my tweets at the time, shouting into the darkness, we do not know. You cannot derive knowledge from ignorance. So if we don't know whether masks work or not, if we don't know whether they stop infected droplets from getting into your respiratory system or not, then we don't know. There isn't a thing you can do. And you can't even do an experiment until you have an explanation. So there are people who work on the theory of masks. And they then can do experiments to determine how many of the droplets will be stopped by the mask. And then there's an additional theory that says that the droplets that occur in real life that have COVID in them, behave in the same way as the droplets they use in these experiments.

[02:20:14]  Unidentified speaker: Right.

[02:20:16]  David: Now, once you have a full chain of explanations, you can test, if somebody doubts one of them, they say, oh, well, the COVID droplets are actually smaller than you think.

[02:20:29]  Unidentified speaker: Okay, you can test that.

[02:20:32]  David: What you can't do is just hand out the masks to 500 people and no masks to the other 500 people, and then see how many die. That will give no information about the theory.

[02:20:48]  Bruce: So, again, we're avoiding any discussion about mandates, but I'm just trying to make a decision about whether I want to wear a mask or if I want to be around people that are not wearing masks, okay?

[02:21:03]  Bruce: And you're right, I don't necessarily have the necessary explanations at this point as to how many of the droplets get through and whether the COVID ones are exceptions or not.

[02:21:14]  Unidentified speaker: And yet I do have to make a decision.

[02:21:19]  Bruce: To say you cannot do this from ignorance, I am ignorant, I know that, right?

[02:21:25]  Bruce: At this point, we're still a ways off at the beginning of 2020 to where we're going to actually have answers to these questions.

[02:21:33]  Bruce: And yet I would make a decision, and I would make a decision based on what explanations I currently have available to me.

[02:21:39]  Unidentified speaker: Is that wrong for me to do?

[02:21:41]  Bruce: And what would be the right way to go about it?

[02:21:45]  David: So as in the case of gambling, your decision depends not only on the probabilities, but also on the payoffs. So if, for example, wearing a mask is completely costless, then you may as well do it, because it's possible that it works, and it's also possible it doesn't work. But if it costs you nothing to wear it, if it costs you something to wear it, then you can't make a decision just based on that. You've got to think about other things of which you are ignorant. So for example, you don't mind walking past a hospital, even though in the past, people have walked past a hospital and have died from getting an infection, like I remember for Legionnaires' disease, that happened once. People got Legionnaires' disease from the air conditioner that was working in the hospital, and they were just walking past and they got Legionnaires' disease and died. So there's lots of things like that that we don't know.

[02:23:02]  David: And we, if something has a cost, we've got to think about, we can't take, if the precaution has a cost, we can't take it for all the things that we don't know. So we've got to have an explanation about what kinds of thing we're going to include in our model of the world. So again, in the case of COVID, we don't know if it behaves like other coronaviruses. Turns out it didn't. But before we knew that, it was reasonable not to make assumptions that there was something novel about this, until we have evidence that there was. But you could die of that. And the people who walked past the hospital with Legionnaires' disease did die of it. And there isn't a strategy that will keep you alive unconditionally.

[02:24:03]  Unidentified speaker: All right.

[02:24:04]  Unidentified speaker: Fair enough.

[02:24:04]  Unidentified speaker: Okay.

[02:24:05]  Peter: I feel like we're getting really greedy with David's time here.

[02:24:08]  Unidentified speaker: Yes.

[02:24:11]  Unidentified speaker: Very, very quick final question.

[02:24:15]  Peter: I've heard you mention your next book in different ways.

[02:24:21]  Peter: I think you said something about maybe writing a quantum physics textbook.

[02:24:25]  Peter: I know there's something about countering the prevailing wisdom on cognitive biases, which sounds super interesting.

[02:24:35]  Unidentified speaker: Maybe I heard you something.

[02:24:37]  Peter: You've got so many ideas that just need to get out there, like something about the pattern, which obviously could not be more relevant right now.

[02:24:47]  Peter: I'd love to hear you write something more about the fun criterion, which is such an interesting idea to me.

[02:24:56]  Unidentified speaker: Can you talk about what are you doing next?

[02:24:58]  Unidentified speaker: When can we expect a book?

[02:25:00]  David: I'm writing several books.

[02:25:02]  Unidentified speaker: Several, okay.

[02:25:03]  David: They are all going very slowly.

[02:25:06]  Unidentified speaker: Okay.

[02:25:07]  David: Especially since I've been preoccupied recently with the pogrom and with writing on X about it.

[02:25:16]  Unidentified speaker: Yes.

[02:25:17]  Unidentified speaker: Yes.

[02:25:18]  David: Some of those things you mentioned will be in my book on irrationality. Though when that's coming out, I do not know.

[02:25:25]  Unidentified speaker: I think it's very probable.

[02:25:30]  David: It's [wording uncertain] joke. The next book that will hit the shelves that I write will be my science fiction book, which is about the Fermi paradox.

[02:25:47]  Unidentified speaker: Okay.

[02:25:48]  Unidentified speaker: Interesting.

[02:25:49]  Unidentified speaker: It's fiction, then?

[02:25:50]  Unidentified speaker: Fiction.

[02:25:51]  David: Well, it's speculation.

[02:25:55]  Unidentified speaker: Wow.

[02:25:55]  Peter: Well, that's something else to look forward to, then.

[02:25:59]  Unidentified speaker: And...

[02:26:00]  David: No one's looking forward to it more than me.

[02:26:02]  Unidentified speaker: Okay.

[02:26:04]  Unidentified speaker: Well, David, this has been one of the highlights of my life.

[02:26:09]  Peter: I want to thank you so much for listening to my questions and coming on this podcast.

[02:26:17]  Unidentified speaker: And just thank you.

[02:26:20]  Unidentified speaker: Yes.

[02:26:20]  Unidentified speaker: Thank you so much.

[02:26:21]  Unidentified speaker: This has been wonderful.

[02:26:23]  Bruce: I've gotten finally gotten answers to many questions that have been burning ever since I read your books.

[02:26:29]  David: Thank you.

[02:26:30]  Unidentified speaker: Glad to hear it.

[02:26:31]  Unidentified speaker: Take care.

[02:26:32]  David: And thanks for having me.

[02:26:40]  Unidentified speaker: Hello again.

[02:26:41]  Peter: If you've made it this far, please consider giving us a nice rating on whatever platform you use, or even making a financial contribution through the link provided in the show notes.

[02:26:51]  Peter: As you probably know, we are a podcast loosely tied together by the Popper Deutsch Theory of Knowledge.

[02:26:58]  Peter: We believe David Deutsch's Four Strands tie everything together.

[02:27:01]  Peter: So we discuss science, knowledge, computation, politics, art, and especially the search for artificial general intelligence.

[02:27:10]  Peter: Also, please consider connecting with Bruce on X at BNielsen01 [spelling uncertain].

[02:27:16]  Peter: Also, please consider joining the Facebook group The Many Worlds of David Deutsch, where Bruce and I first started connecting.

[02:27:24]  Unidentified speaker: Thank you.