Making Sense - Sam Harris - #178 — The Reality Illusion

00:00:00.000 Welcome to the Making Sense Podcast. This is Sam Harris. Okay, housekeeping. Well,

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00:02:48.460 Okay. So today I'm speaking with Donald Hoffman, and I'm joined by my wife, Annika. This is the first

00:02:59.900 time we have jointly interviewed a guest, and I'm sure it won't be the last. Annika's interest in this

00:03:06.960 topic definitely helped us get deeper into it. Donald Hoffman is a professor of cognitive science

00:03:13.120 at the University of California, Irvine. His writing has appeared in Scientific American,

00:03:18.460 and on edge.org, and his work has been featured in The Atlantic, Wired, and Quanta. And his new book

00:03:26.120 is The Case Against Reality, Why Evolution Hid the Truth From Our Eyes. And there was an article in

00:03:33.480 The Atlantic profiling him that made the rounds. He also had a TED Talk that many found bewildering.

00:03:42.520 As you'll hear, he has what he calls a user interface theory of perception,

00:03:47.160 and many people find this totally confounding, and it can seem crazy at first glance, and even at

00:03:56.840 second glance. And I must say, when I first read The Atlantic article and watched his TED Talk,

00:04:03.500 I wasn't entirely sure what Hoffman was claiming. As you'll hear, Annika got very interested in his work

00:04:09.340 and had several meetings with him, and then we finally decided to do this podcast. And it is a fairly

00:04:16.760 steep conversation. I do my best to define terms as we go along. But for those of you for whom this is

00:04:27.260 your sort of thing, I think you'll love it. Over the course of three hours, we really leave virtually no

00:04:35.680 stone unturned. In this area, we talk about how evolution has failed to select for true perceptions

00:04:43.040 of reality. We talk about Hoffman's interface theory of perception. We talk about the primacy of math and

00:04:50.800 logic, and what justifies our conviction there. We talk about how space and time cannot be fundamental

00:04:57.820 to our framework. We talk about the threat of epistemological skepticism. Causality is a useful

00:05:06.520 fiction. The hard problem of consciousness. Agency, free will, panpsychism, what Hoffman calls the

00:05:15.020 mathematics of conscious agents. Philosophical idealism, death, psychedelics, the relationship between

00:05:23.700 consciousness and mathematics, and many other topics. And now Anika and I bring you Donald Hoffman.

00:05:35.780 We are here with Donald Hoffman. Donald, thanks for joining us.

00:05:39.320 Thank you, Sam. It's a great pleasure.

00:05:40.700 So this is unusual. This is the first time that Anika, my wife, who's only been on the podcast once,

00:05:47.400 many of our listeners will remember that podcast. It's the first time anyone has heard me laugh out loud

00:05:52.060 in a decade. So you came to my attention on the basis of an Atlantic article, I think, that was

00:06:01.180 making the rounds. And you also had a TED Talk. I don't know which preceded the other. But then Anika

00:06:06.940 just got completely obsessed with what you were doing. And maybe once a month or so, I would hear that

00:06:13.840 there was some export from a conversation she was having with you. So it just seemed like it would be

00:06:18.740 professional malfeasance for her not to really anchor this conversation. So Anika. 0.67

00:06:25.600 That was all in the context of my writing my book. I was doing research for my book. And

00:06:29.900 Don was working on a book on a similar topic, or really on the same topic, with a different

00:06:34.980 perspective. And so I had wanted his input on my manuscript and was honored that he trusted me with

00:06:43.860 his manuscript. And we kind of we actually gave each other we were kind of in the writing process

00:06:47.060 together. So gave each other notes. And then Don was extremely generous with his time and continued

00:06:53.400 to meet with me as I had many follow up questions. And yeah, yeah, put put up with with my curiosity,

00:07:01.300 even though I'm not sure any of it was helpful to you. But I it was it was great for me to

00:07:07.020 it was very much fun for me and very, very helpful because you also gave me feedback on my book and

00:07:11.500 really helped bring my book to a broader audience as well. So I was grateful. And I was really

00:07:15.740 grateful that you did all the driving. Yeah. Right.

00:07:19.460 So before we jump into your thesis, which is, I mean, has the virtue of being on what I think is

00:07:27.940 perhaps the most interesting topic of all. And some of the points you make are so counterintuitive

00:07:33.100 as to seem crazy on their face. So it's going to be fantastic to wade into this with you. But what is

00:07:39.740 how do you summarize your academic and intellectual background before we get started?

00:07:45.100 Well, so I did my undergraduate bachelor's at UCLA in what was called quantitative psychology. It was

00:07:52.160 like a major in psychology and a minor that had like computer science and math courses in it.

00:07:58.780 And while I was doing that, I took a graduate class with Professor Ed Carter-Retton, which we were

00:08:04.420 looking at artificial intelligence and ran across the papers of David Marr. This is like around 77,

00:08:10.580 78. And his papers just really grabbed my attention. Here was a guy that was trying to build visual

00:08:17.240 systems that worked with mathematical precision, not just waving your hands, but actually writing

00:08:21.940 down mathematics and something that you could actually build eventually into a robotic vision

00:08:26.180 system. So I found out he was at MIT in the AI lab and what's now the brain and cognitive sciences

00:08:31.780 department. And I was lucky enough to get to go there and work with him. He died a little over

00:08:38.900 a year after I was there. So I only got to work with him for 14 or 15 months.

00:08:42.820 Yeah, very young. He was like 35, right?

00:08:44.660 35. He had leukemia. But I did get to work with him and see how his mind works. It was revolutionary.

00:08:51.940 It was a wonderful time there at MIT. And then my other advisor was Whitman Richards. David Marr and

00:08:59.700 Whitman Richards were my joint advisors. And then Whitman was my sole advisor after Marr died. And

00:09:05.300 so I was very interested in going there in the problem of, you know, are we machines? And I figured

00:09:12.580 what better way to get at that question than doing something in an artificial intelligence lab where we

00:09:17.860 try to build machines and understand the scope and limits of what machines could do. So I was always

00:09:22.740 very interested in human nature and how, you know, artificial intelligence is related to humans. Are

00:09:28.420 we just artificial intelligence as ourselves, just machines, or is there something more? And I didn't

00:09:33.380 want to hand wave. I really wanted to understand what it means to be a machine and what might be

00:09:38.180 different or not about humans. And so that's sort of my intellectual background. And what I focused on

00:09:44.420 because, you know, of Marr was perception, visual perception.

00:09:48.100 Yeah. So he wrote a book that was quite celebrated, a very, you know, early detailed look at visual

00:09:54.580 perception, which it's amazing what a contribution he made in such a short time. Decades after his death,

00:10:02.180 you know, his book is still recommended as a must read book in cognitive science and neuroscience.

00:10:07.700 Absolutely. It was brilliant. And he was brilliant in person. The, the, the lab meetings were,

00:10:13.220 were electric. He had assembled this world-class group of scientists around him. They, they, they

00:10:21.140 congregated around him. And I, I just was so lucky to be watching this new science being revolutionized

00:10:27.700 by, by this young man. Yeah. At 35, he, he did all this and died. It was, it was truly stunning.

00:10:34.820 Yeah. You're now at Irvine as a professor, right?

00:10:37.540 That's right. University of California at Irvine.

00:10:39.140 Yeah. And you have been meeting over the years with some of the great lights in

00:10:46.500 consciousness studies, for lack of a better word of it. There was these meetings of the Helmholtz

00:10:51.220 society. Isn't that what you were called?

00:10:52.980 Yeah. The Helmholtz club.

00:10:53.700 Helmholtz club. Yeah. So, so, uh, and that had Francis Crick in it. And I never met Francis,

00:10:58.900 but Joe Bogan, who you write about in your book is somebody who I, who I did meet and he was

00:11:03.140 quite a character.

00:11:03.780 He's quite a character.

00:11:04.420 Yeah. He was fun at dinner.

00:11:06.340 Yeah. He's, he was the neurosurgeon who did the bulk of the split brain procedures for which

00:11:12.340 Roger Sperry won the Nobel prize. And that's right.

00:11:16.020 And, uh, Ron Zeidel at UCLA was involved in that work and Michael Gazzaniga.

00:11:19.700 Yes.

00:11:20.100 Yeah. Before we jump in, I want our listeners to be sensitized to how seemingly preposterous

00:11:30.500 some of your initial claims will be. And, and I, and I can guarantee you that on certain of these

00:11:36.580 points, the sense of their counterintuitiveness will wear off. And there's something thrilling

00:11:42.500 about this. I mean, this is the thrill that was exemplified by Annika's obsession with your work.

00:11:48.260 I know has spread to, uh, other people. We have a friend who perhaps I shouldn't name who claimed that

00:11:54.020 she, she accosted you at some function and just completely fangirled you as a, as a groupie. 0.67

00:11:59.060 So we know that I think once you start wearing sunglasses indoors, you will, you will have

00:12:04.740 started a cult and then we will put the word out against you. But, um, in the meantime, perhaps

00:12:11.380 the best place to start, I mean, I would imagine we should just track through it the way you do it

00:12:15.380 in your book, starting with the interface theory of perception, but you can start wherever you want.

00:12:20.100 And we, we just want to go through it all and we'll have questions throughout.

00:12:23.140 Right. So most of my colleagues who study perception, assume that evolution by natural

00:12:33.220 selection has shaped us to see truths about the world. None of my colleagues think that we see

00:12:40.260 all of reality as it is, but most of my colleagues would argue that accurate perceptions, what we call

00:12:47.060 veridical perceptions, perceptions that tell us truths about the world, will make us more fit.

00:12:52.020 So accurate perceptions, veridical perceptions are fitter perceptions. And the argument that's

00:12:58.740 classically given is actually quite intuitive. So, so the idea is that those of our ancestors who

00:13:04.740 actually were better at feeding, fighting, fleeing and mating because they could see reality as it is,

00:13:09.620 were more likely to pass on their genes, which coded for the more accurate perceptions. And so after

00:13:15.860 thousands of generations of this process, we can be quite secure that our perceptions are telling

00:13:21.780 us truths about the world. Of course, not exhaustive truths, but the truths that we need. We see

00:13:27.460 those aspects of reality that we need to stay alive and reproduce. And that seems like a really

00:13:33.380 compelling argument. It seems very, very intuitive. How could it go wrong?

00:13:36.420 So at first glance, it seems some measure of veridicality, some measure of being in touch with

00:13:43.380 reality as it is would increase an organism's fitness. There must be a fit between tracking

00:13:52.420 reality as it is and adaptive advantage.

00:13:55.220 Dr. Exactly. That's, that's the standard intuition for, for most of my colleagues.

00:13:59.940 Stephen Pinker has actually published papers where he points out some, some contradictions to that idea.

00:14:06.500 But most of my colleagues would go with the idea that, yeah, it's, it's better. It's more fit to

00:14:11.380 see reality as it is, at least part of reality. Well, I began to think that that might not be true

00:14:18.740 because my initial intuition was that maybe it would just take too much time and too much energy

00:14:24.740 to see reality as it is. So evolution tries to do things on the cheap. So maybe

00:14:29.620 the pressures to do things quickly and cheaply would, would maybe compromise our ability to see the

00:14:35.060 truth. And so I began to work with my graduate students at Justin Mark and Brian Marion around

00:14:40.180 2008 or so, 2009. And I had them write some simulations where we would simulate foraging

00:14:48.500 games where we could create worlds with resources and put creatures in those worlds that could roam

00:14:52.900 around and compete for resources. And some of the creatures we let see all the truth. So they were

00:14:58.820 the vertical creatures and others I didn't let see the truth at all. We, we had them only see the

00:15:04.420 fitness payoffs and we can talk about what fitness payoffs mean. That's an important concept. But

00:15:08.980 what we found was in these simulations that the, that the creatures that saw reality as it is

00:15:16.180 couldn't out-compete the creatures of equal complexity that saw none of reality and were just tuned

00:15:22.420 to the fitness payoffs. And so that began to make me think there was something real here. So now I should

00:15:28.420 say what fitness payoffs are. So think in evolution, you can think of evolution by natural selection

00:15:35.540 much like a video game. So in a video game, your focus is to collect points as quickly as you can

00:15:44.340 without being distracted by other things. And if you get enough points in a short enough time,

00:15:49.380 you then might get to go to the next level. Otherwise you die. And in evolution by natural selection,

00:15:54.500 it's very, very similar. The, instead of the game points, you have fitness payoffs and you

00:16:01.540 go around collecting them as quickly as you can. And if you get enough, you don't go to the next

00:16:06.740 generation, but your genes get passed to the next generation. And so, so to be a little bit more

00:16:11.940 specific, think about the fitness payoff that say a T-bone steak might offer. So that if you're a hungry

00:16:20.660 lion looking to eat, that T-bone steak offers lots of fitness payoffs. But if you're that same

00:16:26.740 lion and you're full and you're looking to mate, all of a sudden that T-bone steak offers you no

00:16:31.300 fitness payoffs whatsoever. And if you're a cow in any state and for any activity, that T-bone steak

00:16:36.900 is not going to, is not a fit thing for you whatsoever. And, and so that's gives you an intuition

00:16:43.700 about what we mean by fitness payoffs in evolutionary theory. Fitness payoffs do depend on the state of

00:16:51.700 the world, whatever the objective reality might be. They do depend on the state of that world,

00:16:55.540 but also, and importantly, on the organism, its state and the action. And so fitness payoff functions

00:17:04.820 are very complicated functions. And the state of the world is only one of the parts of the domain of

00:17:11.220 that function. There's lots of other aspects to it. And so they're really, really complicated

00:17:15.300 functions of the state of the world and the organism, its state and its action.

00:17:18.740 Right. Well, so now I think you should introduce the desktop analogy, because again,

00:17:24.420 what you just said can sound suspiciously similar to more or less what every life scientist and

00:17:32.340 certainly neuroscientists would agree is true, which is whatever reality is, we see some

00:17:41.140 simulacrum of it that is, you know, broadcast to us by the way our nervous system sections up the

00:17:47.540 world. So, you know, we see within a certain bandwidth of light, you know, bees detect, you know,

00:17:52.820 another bandwidth. And we, by the very nature of this, don't get all the information that's available to

00:18:01.460 be gotten. So we don't have a complete picture of the thing in itself or the reality that's behind

00:18:08.180 appearances. But implicit in that kind of status quo assumption is that the things we do see

00:18:17.940 really exist out there in the real world in some basic sense in space and time. Again, it's not clear

00:18:26.740 how much gets lost in translation, but there is some conformity between what we see as a glass of

00:18:32.580 water on the table and a real object in the world in, you know, third-person space. How is your vision

00:18:41.540 of things departing from what is now scientific common sense? Yeah, it does depart dramatically from

00:18:46.500 that standard view. The standard view, as you said, is that we may not see all of the truth, but we do see

00:18:51.940 some aspects of reality accurately. And what the evolutionary simulations and then later theorems that

00:18:58.340 my colleague Chaitan Prakash proved indicate is that our perceptions were shaped by natural selection

00:19:06.100 not to show us just the little bits of truth we need to see, but rather to hide truth altogether and to

00:19:12.340 give us instead a user interface. So, you know, a metaphor I like to use is if you're writing a book

00:19:19.140 and the icon for the book is blue and rectangular in the middle of your screen, does that mean that

00:19:25.540 the book itself in your computer is blue rectangular in the middle of the computer? Well, of course not.

00:19:30.580 Anybody who thought that really misunderstands the point of the user interface. It's not there

00:19:35.860 to show you the truth, which in this metaphor would be the circuits and software and voltages

00:19:41.300 in the computer. The interface is there explicitly to hide the truth. If you had to toggle voltages to

00:19:50.740 write a book, you'd never get done. And if you had to toggle voltages to send an email, people would

00:19:54.980 never hear from you. So the point of a user interface is to completely hide the reality and to give you

00:20:04.580 very, very simplified user interface to let you control the reality as much as you need to control

00:20:10.020 it while being utterly ignorant about the nature of that reality. And that's what the simulations that

00:20:16.820 I've done with my students and the theorems that I've done with with Chaitan Prakash indicate is that

00:20:22.340 natural selection will favor organisms that see none of the truth and just have this simplified

00:20:30.820 user interface. So to be very explicit, three-dimensional space, as we perceive it,

00:20:36.980 is just a three-dimensional desktop. It's not an objective reality independent of us.

00:20:41.860 It's just a data structure that our sensory systems use to represent fitness payoffs and how to get them.

00:20:49.700 And three-dimensional objects like tables and chairs, even the moon, are just three-dimensional icons

00:20:55.140 in that interface. So once again, they're not our species representations of a true glass that's really

00:21:04.340 out there or a true table that's out there. They are merely data structures that we're using to represent

00:21:10.020 fitness payoffs and how to get them.

00:21:11.940 So yes, in this first description of this wonderful analogy you use with the desktop and also of how

00:21:21.300 evolution gives us this false picture of what the deeper reality actually is. I have a few questions

00:21:27.700 here. I'm going to start, I'm not quite sure where it will go, but there are at least three things that

00:21:32.580 have been brought up so far that I feel like it's important for us to get clear on terminology and

00:21:38.580 framework before I start really disagreeing. And I should say that you and I have now spent

00:21:45.860 many meetings together. I spend a lot of time challenging you, mostly because I actually think

00:21:50.580 there's something very interesting that you're doing and I think you're onto something. And so,

00:21:54.820 you know, in the same way that in my editing work, I give the most notes to the books I'm most

00:22:00.100 passionate about. It's in that spirit. So beginning with evolution, I've actually said to you many times

00:22:06.660 that I don't actually think you need the evolution argument to make your case for your theory.

00:22:12.420 So some of the, some of this pushback is actually moot, but I still think it's interesting. And I think

00:22:17.460 I agree with this, with this evolution argument up to a point. So my, my first question is really to

00:22:24.420 just get us, you know, on the same page or see if we are on the, on the same page as a starting point.

00:22:29.020 I know that you believe that, or you're hopeful, you're optimistic about the fact that we can

00:22:37.020 ultimately understand what that deeper reality is. And so that, so there must be boundaries

00:22:44.940 to the systems that we're using, our brains, which have evolved, where we can actually get access

00:22:52.620 to the truth. So, so up until to a point, our brains are giving us all of this false information,

00:22:58.860 but there's some sense in which we can actually get access to things that are true about the nature

00:23:04.220 of reality. So my question is, where do you draw the boundary of an evolved system that by definition

00:23:11.980 gives us false information about the nature of reality? So that outside that boundary is where we

00:23:18.160 might be able to gain access to information that delivers us the truth. And there's kind of a

00:23:23.260 second part to that, which is where we might disagree. I believe we've already begun to cross

00:23:29.180 that boundary with science. And so the way I follow your evolution argument is simply about direct

00:23:36.480 perceptual information that we get rather than ideas, scientific experiments. So, so if you just take

00:23:46.060 light, light, I think is always the simplest example, we have not evolved perceptual systems

00:23:51.460 to really understand what light is, right? Like everything, everything we've learned about light

00:23:56.040 through the sciences, up to quantum mechanics, where it gets completely mysterious, and we really

00:24:01.600 don't actually know what light is. So, so we can kind of all agree, and not just the three of us in

00:24:08.180 this room, but all of us, you know, most scientists would agree that ultimately, we're still,

00:24:13.560 we still don't have this information about what the fundamental nature of reality is. We're, we're,

00:24:19.740 we're still stuck there. But I would say that we have learned, we've gotten much closer to that

00:24:26.120 by these processes that I think are outside the boundary of this evolved system that is by definition

00:24:35.880 delivering us false information. Right. Great question. And there's a couple points about it. First, that

00:24:43.560 the, the arguments that I've given from evolution by natural selection against veridical perceptions

00:24:49.520 do not hold against math and logic. So that's very, very different than some other like Christian 1.00

00:24:59.740 apologists like Alvin Plantinga, who have made an argument that sounds very similar to mine,

00:25:04.600 that they say that if our senses, if our cognitive capacities evolved, they would be unreliable.

00:25:10.460 That includes our theory building capacity, and therefore the theory of evolution is unreliable,

00:25:14.820 and therefore evolution is false. I'm making no such argument. Right. I'm, it's further,

00:25:19.760 the furthest thing from my mind. I'm focused only on the senses. And the reason why the argument

00:25:25.760 that says our senses are not veridical doesn't hold for math and logic is that

00:25:29.880 there are evolutionary pressures for us to reason about fitness payoffs. Two bites of an apple give

00:25:39.500 you roughly twice the fitness payoff of one bite of an apple. Whatever objective reality might be,

00:25:44.840 we need to be able to reason about fitness payoffs. And so, whereas the selection pressures are

00:25:50.240 uniformly against veridical perceptions, they're not uniformly against some elementary competence in

00:25:57.840 math and logic. Now, I'm not, of course, arguing that natural selection is shaping us to be geniuses

00:26:02.900 of math and logic. Far from it. It's just that the selection pressures are not uniformly against

00:26:07.420 ability. And every once in a while you get a, you know, a genius coming up.

00:26:11.340 But don't we think the math and logic are giving us space-time? I mean, this can get into a deeper

00:26:17.900 question because, of course, we now have quantum mechanics, which is putting all of this into

00:26:22.220 question. And many physicists, if not most, are talking about space-time being something that

00:26:28.360 emerges out of something more fundamental. But they would still say that it emerges. And so,

00:26:33.800 it seems that it's hard to take. So, I guess my argument with where you take this evolution

00:26:43.020 argument is as far as space-time itself. Because it seems that we don't yet know whether or

00:26:52.220 space-time is a true illusion in some sense. But I would say our math and logic has taken us

00:26:59.140 that far, not simply our perceptual systems.

00:27:04.320 Actually, let me see if I can add to this point, because this is something that came up for me as

00:27:09.540 well. So, if we confine this to perception, for me, it's no longer counterintuitive. But again,

00:27:16.220 this will be counterintuitive for many, many people. But so, the claim is that

00:27:22.220 fitness trumps truth so fully that apprehending the truth, perceptually, is just not an evolutionarily

00:27:31.180 stable strategy. You're going to be driven to extinction among creatures that are optimized

00:27:35.520 for fitness. And that sounds a little crazy. But when you think of what fitness means,

00:27:41.020 fitness means simply being optimized for survival and procreation, right? So, as long as you're

00:27:47.920 optimizing for that, it's easy to see that you successfully out-compete anything that isn't

00:27:52.900 optimized for that. And there's also this additional piece, which you mentioned, which is that there's

00:27:58.380 clearly fitness value, i.e. survival value, in throwing away information that isn't related to

00:28:06.620 fitness, right? So that every organism is going to have some bandwidth limits and metabolic limits,

00:28:12.340 and tracking every fact that's out there to track can't be a priority. And then there's this additional

00:28:20.360 component, which is if the inability to make certain distinctions doesn't relate to increased

00:28:25.420 fitness, evolution would not have selected for that ability to make those distinctions, right? So you'll

00:28:30.540 expect organisms to be blind to certain features of reality just in principle. But there is a sense in

00:28:38.220 which your thesis does bite its own tail and seems to at least potentially subvert itself in that

00:28:47.860 the moment you start to say that, okay, space and time, they don't exist, they're data structures,

00:28:54.100 therefore our notion of objects is a pure interface issue. It's just, it's like a trash can on the

00:29:00.240 desktop. It doesn't really map onto reality as it is. You just bracketed logic and rationality.

00:29:07.160 Mm-hmm. Which may be defensible, but evolution itself, the very notion of natural selection

00:29:13.920 is more than just rationality. It is a causal picture. And we might say that causes, and the

00:29:20.960 notion of cause and effect, right, or the notion that causes precede their effects rather than some

00:29:26.540 notion of teleology, these things are also just data structures. So that like every piece you want

00:29:34.040 to put on the board to give a Darwinian account of anything does sort of fall in the bin of more

00:29:40.120 space and time, more objects. And so how doesn't this thing completely subvert itself and land you

00:29:45.600 in something like just a global skepticism, which says, you know, we're in touch with some seeming

00:29:51.940 reality which we really can't ever know anything fundamental about?

00:29:57.120 Yeah, great question, both of you. So the idea first that evolution by natural selection,

00:30:03.660 as we all know and love it, involves things like DNA and organisms in space and time and so forth.

00:30:10.880 So how could I ever use the theory of evolution to show and claim to show that things like DNA

00:30:15.860 are just data structures? They're just interface symbols. And the reason I can do that is because

00:30:22.800 John Maynard Smith actually took the theory of evolution by natural selection and mathematized

00:30:29.320 it. He realized that we could abstract away from all of the sort of the extraneous empirical

00:30:33.940 assumptions of space and time and DNA and so forth. And we could look at what he calls just

00:30:38.980 evolutionary game theory. And so that the logic of natural selection itself can be reduced to

00:30:44.780 competing strategy, where you make no ontological assumptions whatsoever about the world in which

00:30:50.600 those strategies are playing. So it allows one, when someone says natural selection favors true

00:30:58.840 perceptions, evolutionary game theory provides you precisely the tool you need to ask how to assess

00:31:05.900 that question independent of all these other empirical assumptions that are standard in biological

00:31:11.300 evolutionary theories. And so that allowed me to do this. Now, there's another aspect to the

00:31:17.660 argumentative strategy that I'm taking here. And that is that one reason that I went after the

00:31:23.540 evolutionary argument was I actually announced the interface theory in my book in 1998, Visual

00:31:28.780 Intelligence. And people liked the book except for the chapter on the interface theory. And I thought

00:31:33.040 that was nuts. And I realized I wasn't going to get my colleagues to pay attention to that idea

00:31:38.200 unless I talked to them in a language that they really understood. And it was that that motivated me

00:31:43.400 to go after the evolutionary argument a few years later. So the reason I use evolution is not because

00:31:49.100 maybe it's the best argument, it's because it's the argument that I knew my colleagues would listen

00:31:53.940 to. So first, I'm abstracting away from the whole apparatus of biological evolution to just the

00:32:00.220 nuts and bolts of evolutionary game theory, which doesn't bring the ontological assumptions.

00:32:05.200 And second, my attitude as a scientist toward any scientific theory is they're just the best tools we have

00:32:10.980 so far. I don't believe any scientific theories, including my own. I think belief is not a helpful

00:32:16.100 attitude. This is the best tool we have so far. Let's look at what this tool says about the claim

00:32:22.560 that natural selection favors vertical perceptions. And whatever deeper, so what that tool is saying to

00:32:29.340 me is there's just no grounds for thinking that any of our perceptions of space and time and objects

00:32:34.940 in any way capture the structure of whatever objective reality might be.

00:32:41.540 And one thing that's nice about this mathematics as well is you might say, well, how in the world

00:32:45.880 could you possibly show that the structure of our perceptions doesn't capture the structure of the

00:32:52.020 world unless you knew already what the structure of the world is? I mean, aren't you shooting yourself in the

00:32:56.640 foot there? And it turns out you don't have to, it's really that wonderful in the mathematics that you can

00:33:02.680 show that whatever the structure of the world might be, the probability is zero, but that's what we're

00:33:08.240 seeing.

00:33:08.560 Right. And that makes sense to me too. I'm still stuck on how it extends all the way to space and time.

00:33:17.800 And I think we shouldn't spend too much time on the evolution piece, mostly because I actually think

00:33:23.940 you don't need it. But just from a philosophical perspective, I think it's very interesting. And I'm still

00:33:30.340 curious myself kind of how far this goes, because it's clearly true up to a point at least. So if

00:33:38.040 Darwinian evolution by natural selection is a theory about objects in space and time, I mean, this is

00:33:44.860 just a question for you about how you view this. Where can you stand outside of space, time, and matter

00:33:52.000 to talk about evolved perceptual systems? But more specifically, what does evolution look like? Or

00:34:01.740 how do you even talk about evolution outside of space, time? So what are we saying is evolving?

00:34:07.400 What are we saying is surviving? What do evolution and survival even mean in a context outside of space

00:34:14.600 and time? Or is that just an abstract idea that you haven't?

00:34:17.780 No, that's the right question. And that's the power of evolutionary game theory. What John

00:34:22.860 Maynard Smith was able to do was to show we could talk about abstract strategies competing,

00:34:29.560 not in any particular assumption about space and time. He was able to abstract away from all the

00:34:35.940 details of biological evolution in space and time and organisms and say the essence of Darwin's idea

00:34:43.380 are these abstract strategies. And we can look at how these strategies compete in an abstract space.

00:34:51.440 So what is it that's surviving? It's an idea? It's a meme? It's a, what survives?

00:34:56.520 So what you do is you have an, you imagine that there are, there's a population of entities that are

00:35:04.640 competing using these strategies. So they're abstract entities in an abstract space with these strategies.

00:35:10.420 And what you do is you, you just, there's something called the replicator equation. And what you find

00:35:16.580 in the replicator equation is that the number of entities that have a good fitness strategy will

00:35:22.840 start to increase. Their proportion will increase. The strategies that have a bad fitness strategy

00:35:27.680 or, you know, a lesser strategy. And so what you have is the proportion of the population

00:35:34.060 that has various strategies goes up and down.

00:35:37.280 Well, then I guess my question goes back to what, what do you mean by entity?

00:35:41.380 So these are just abstract entities that, that in evolutionary game theory,

00:35:45.480 you don't need to know what the entities are. They're, they're just place markers.

00:35:48.440 You're imagining they're, they're entities outside of space and time.

00:35:52.640 That's, and that's what the mathematics allows you to do.

00:35:54.960 Well, let me just piggyback on this. Now you're getting tag team. 0.95

00:35:58.160 Oh, that's, that's what I was hoping for.

00:35:59.580 So, uh, I apologize in advance, but isn't the very notion of competition and differential

00:36:07.020 success based on the parasitic on the notion of time, parasitic on the notion of causes preceding

00:36:14.680 their effects and entities is, you know, I think what Anika is fishing for there is entities

00:36:20.000 seem somehow derivative of objects, at least the concept of an object. I mean, we're talking

00:36:26.260 about something that's discrete, that's not merely a continuous reality, right? Things

00:36:32.220 can be differentiated. So how are we not using the same cognitive tools that have got hammered

00:36:37.360 into us by evolution, whose process is only selected for fitness and therefore left us

00:36:43.400 epistemologically closed to the nature of reality?

00:36:46.420 Absolutely. So you're right that the evolutionary, the replicator equation itself does have a time

00:36:52.260 parameter, right? Or at least a sequence parameter. It depends on whether you do it discreetly or,

00:36:56.240 or continuously. And so that's going to be built into it. Absolutely. So by the way, as I said,

00:37:02.340 I'm not committed to the truth of evolution by natural selection. I'm just using that theory

00:37:07.580 itself to say that whatever the structure of the world is, that that theory says the chance is zero

00:37:14.680 that our perceptions actually have captured that structure. It leaves it open to ask, is there a

00:37:21.080 deeper theory of objective reality that will give back evolution by natural selection as a special

00:37:26.680 case within what I call our space-time interface? And that's actually what I'm hoping for is to have

00:37:32.220 a deeper theory that will have, that'll go beyond space and time. It'll go beyond time in the sense

00:37:37.840 that there will be sequence and there will be perhaps a notion of cause following effect, but not in a

00:37:44.240 global space-time temporal framework. It'll be completely asynchronous and so forth. And we'll get

00:37:50.660 what we call causality in like a Minkowski space, Einstein's Minkowski space or a general relativistic

00:37:56.200 curved space-time as a projection of a much more deep theory of reality in which the very notion of

00:38:05.260 dimension doesn't hold and which time doesn't hold. But we can show that though, that so far, I'm thinking

00:38:10.420 about dynamics on, on abstract graphs and asynchronous dynamics, but that can be projected

00:38:16.860 and simplified into what we call space-time and its causality, say in Minkowski space.

00:38:21.600 Mm-hmm. I think it's just useful as a, as a launching off point to, to every place we'll go from here

00:38:28.140 to just say that at the very least, I think this evolution argument is very useful in terms of

00:38:35.600 opening our eyes to something that I actually think we, in some sense, we already know. And,

00:38:41.380 and again, you know, looking at something like light is a good example where we clearly, we have not been

00:38:46.800 given any tools, perceptual tools to understand how electrons operate, how, you know, what is actually

00:38:55.860 happening at a fundamental level. And, and of course there are all these theories now from

00:39:00.420 everything in string theory to many worlds, trying to sort out all of these things that we see through,

00:39:06.300 through our science that we have absolutely no intuitions for, we have no insight into, we're just

00:39:10.720 getting at through math and logic. And, and, and so clearly we haven't evolved systems that help us

00:39:16.360 here. And so I feel like we can agree to two points that we can move from here onward. And, and the first one is that

00:39:25.860 we can all agree, and, and, you know, scientists in general, we don't know what's fundamental,

00:39:31.020 nor do we perceive the truth about the fundamental building blocks of reality. And two, and this is

00:39:37.880 where I'd like to set this up for, for where consciousness is going to, it was about to come in,

00:39:43.280 we can agree that physical science has not given us an explanation for consciousness. We have no

00:39:49.240 understanding of how consciousness arises out of physical processes. And so it seems that we can at least

00:39:54.520 agree that it's a legitimate question or it's a legitimate project to wonder if consciousness is

00:40:00.360 something that's more fundamental and that we're missing that piece and that, that we've thought

00:40:04.420 about it backwards all this time. And that's one of the things that I think is so great about your

00:40:08.600 work. And I think this is a very important project.

00:40:11.920 Okay. So before we get to consciousness, which is central to our interest and where there's more

00:40:18.060 controversy, at least in my mind, I want to anchor what you've said to a very straightforward perception

00:40:24.900 so that our listeners can get in touch with how counterintuitive your thesis is. So when, you know,

00:40:32.980 the three of us are in a room together, apparently there are objects we can see, what is the status of

00:40:39.980 those objects like a glass of water when none of us are looking at it? And what is its status given

00:40:51.000 the fact that it apparently is always there for any one of us to look at? We have some kind of

00:40:57.360 consensus, intersubjective language game we can play here that can reference the glass of water,

00:41:04.260 water, you know, at will. How does that map onto your theory of non-veridical perception?

00:41:10.300 Right. So I think a good way to see what I'm saying and how counterintuitive it is,

00:41:14.820 is to think about, say, playing a game like Grand Theft Auto, but with a virtual reality add-on.

00:41:21.500 So you're, you have a headset and you're seeing a three-dimensional world of cars and your own

00:41:26.100 steering wheel and so forth. And, and it's, it's a multiplayer game. So there are people around

00:41:29.840 the world that, that see the same car that you're driving and see all the other cars that you see.

00:41:35.360 And in that case, there of course, is no real car that anybody's seeing. There's just some,

00:41:42.680 in this metaphor, a bunch of circuits and software and so forth, that that's the objective reality in,

00:41:47.820 in this metaphor. But all the players will agree that they see a red Corvette chasing,

00:41:53.520 you know, a green Mustang down the highway at, you know, 70 miles. They, they all agree,

00:41:58.260 not because there's literally a red Corvette chasing a green Mustang. There is some objective

00:42:02.620 reality, but it's not, it's not Corvettes and Mustangs. That's what we each see. And, and each

00:42:08.840 person with their own headset is getting, in this example, photons, you know, thrown to their eyes

00:42:15.020 and they're rendering in their own mind, the Corvette chasing the Mustang. So there are as many

00:42:21.320 Corvettes and Mustangs as there are people playing the game because they each see the one that they

00:42:26.640 render. And I might be looking at the, at the Corvette and I, I'm, I look away and I'm now

00:42:33.000 looking at my steering wheel. I no longer see the Corvette. I've, I have garbage collected the

00:42:37.560 Corvette. I'm not making that data structure anymore. Now I'm rendering a steering wheel.

00:42:42.680 And now I look back over at the Corvette. Now I'm re-rendering the Corvette. So, so it looks like

00:42:47.940 the Corvette was always there because, you know, when I look away and look back, it's, it's right where I

00:42:52.180 expect it to be. But in fact, there, there is a reality. It's not Corvettes, it's not Mustangs,

00:42:56.780 it's not steering wheels. So, so, and now I, so here's the counterintuitive claim. I'm claiming

00:43:01.960 we all have a headset on. Yeah. All of us. Yeah. And we all have this space, time, physical objects,

00:43:08.660 the glass of water. Those are all things that I render on the fly when I look at them. And then I

00:43:14.260 garbage collect them. And, and that's part of the evolutionary argument. I garbage collect them

00:43:18.980 because I'm trying to save energy and time and memory. So I render it only as I need it. And

00:43:25.000 it's really just the glass I'm seeing is a representation of fitness payoffs. Those are

00:43:29.720 the fitness payoffs I need to pay attention to now. Now I'm throwing that fitness payoff description

00:43:33.900 away. Now I'm looking at fitness payoffs over here. So it's, it's a rapid rendering of fitness

00:43:38.460 payoffs in real time. So here's one of the areas where I worry that the language that you're using,

00:43:45.900 the terminology you're using may actually give a false impression of what you're saying. This

00:43:50.420 is where some of my notes came in. I don't know how many of these notes that you, you have taken

00:43:55.740 or, or will take, but I worry that I actually think I agree with you there, but, but there's

00:44:00.000 something about the way you're saying it that I think gives a false impression of what you're saying.

00:44:04.380 So if you say, you know, the, the race car isn't there, you know, the moon is an example you give

00:44:09.300 often. I mean, you, you also will say, which, which I think is, is more accurate and closer to what

00:44:14.760 you're saying is something exists. Something is, is there in reality that my perceptual systems are

00:44:21.040 kind of turning into this, this site of a moon. And I think it's confusing to readers and listeners

00:44:28.120 when you say it doesn't exist as if the fundamental nature of reality behind whatever that moon is

00:44:36.040 doesn't exist, that there's, that there's nothing there.

00:44:39.040 Fair point. I agree. So it seems more accurate to say, we simply don't understand the deeper

00:44:44.460 reality behind the moon and behind apples. And that this is something in a way, like it's less

00:44:51.300 controversial. This is something we can all admit given our, our current understanding of the physics.

00:44:56.200 And so I, part of my, my gripe there, I think is just with the language that you're using.

00:45:01.880 And there's something incredibly interesting about that, that, that something is there.

00:45:05.560 There's something I'm interacting with. The example I often like to use with you when

00:45:09.040 when we meet as a tree, if we plant a tree and, and leave it, it is, it is out of our

00:45:14.140 conscious experience. There are all these processes that will be taking place in, you know,

00:45:18.400 what we call them, how we view them as water and nutrients being sucked up from the earth and

00:45:22.980 it will grow and we'll come back in a year. And all of those processes would have taken place,

00:45:27.340 whatever they are at bottom, we, we may not understand, but something is going on in the universe

00:45:33.640 that we have our access to. However far from the truth it is, there is something taking place there.

00:45:41.240 And so to explain it as when I leave, there's absolutely nothing there and there's no tree.

00:45:47.640 And then I come back and somehow I create this as if it's...

00:45:51.640 Yeah, I think that's a very important clarification. So I agree with you completely that I'm not saying

00:45:56.320 that there isn't an objective reality that would exist even if I don't look at it. There is an

00:46:00.480 objective reality. It's just that the way, what I see is utterly unlike that objective reality. And in

00:46:06.980 the, the metaphor that I was giving of virtual reality, I might see a red Corvette. The reality

00:46:15.300 in that metaphor would be circuits and software that aren't red, that don't have the shape of a

00:46:19.540 Corvette. They're utterly unlike a Corvette. But, but when I interact with that objective reality

00:46:23.940 that's there, even if I don't see the Corvette, I then will see the Corvette. So that's how

00:46:28.560 different. I think it's potentially confusing as an analogy only because as a user of video games,

00:46:34.800 you can turn, you can turn the video game off. It's not a self-sufficient world. It's not reality

00:46:41.180 that, that continues on and does its, does its thing. I agree with you on that. Or at least,

00:46:45.740 yeah, it gives a slightly false impression. So. Right. I agree that the reality is continuing on

00:46:50.820 regardless of what, I have life insurance. Right, right. And, and, and the reason I have life

00:46:55.320 insurance is because I agree with you that there is some, some reality that will continue to go on

00:46:59.100 even if I'm, if I'm not here. Right, right. Okay. So let, let me make that point with a slightly

00:47:05.500 different topspin because those concessions seem to bring us back to the standard consensus view of

00:47:12.800 science in some way. So there's this appearance reality distinction. There's our sensory experience,

00:47:19.140 which is our interface, which, you know, everyone agrees does not put us in direct contact with the

00:47:25.660 thing in itself or underlying reality. But you're conceding that there is an underlying reality

00:47:32.420 and there must be some lawful mapping between what we see on the interface and that underlying reality,

00:47:41.360 which actually renders our mutual perceptions of things like trees and glasses and cars predictable,

00:47:49.140 where we can both agree that if we go to look for the same object, each one of us is likely to

00:47:54.540 independently find it, whatever the relationship is between that interface data structure and reality

00:48:01.220 itself. So there's, there has to be some kind of isomorphism between our virtual reality experience

00:48:07.380 and reality itself, even though we don't have, by virtue of evolution, all of the right conceptual

00:48:15.080 tools so as to say what it is. There is going to be a mapping between objective reality and,

00:48:22.220 and our perceptions. And that mapping will be as complicated or more complicated as the mapping

00:48:27.560 between all the circuits and software in a virtual reality machine and the actual like Grand Theft Auto

00:48:34.840 world that I, that I perceive. And if you think about it, there's going to be hundreds of megabytes of

00:48:40.660 software, all these complicated circuits, all I'm seeing is simple cars and so forth. So there's

00:48:46.560 going to be in computer science, there are all these virtual machines that you create, many,

00:48:49.860 many levels of virtual machines between what you see in, in the Grand Theft Auto game and the actual

00:48:55.600 objective reality in this metaphor that's going on there. And so I'm saying that, that the idea that,

00:49:00.380 that the reality is going to be isomorphic to space-time is too simplistic, right? There's going to be some,

00:49:08.260 I agree that there's going to be some systematic mapping is going to be quite complicated. So

00:49:13.880 another way to put it is this, if I said to you, I want you to use the language of what you can see

00:49:19.460 in your interface in the virtual reality. So the pixels that you can see, the colors and pixels,

00:49:24.280 that's the only language you can use. And I want you to tell me how this virtual world works.

00:49:28.840 You can't do it because the language of pixels is an inadequate set of predicates to actually

00:49:34.020 describe that world. And I'm making the very strong claim that whatever objective reality is,

00:49:39.320 the language of space and time and physical objects in space and time is simply the wrong

00:49:44.620 language. There is a systematic mapping, but the language of objects in space and time could not

00:49:51.060 possibly frame a true description of that objective reality. That's the strong claim.

00:49:56.560 So it's similar to J.B.S. Haldane, the famous physiologist, gave us an aphorism that almost

00:50:04.800 contains this thesis in seed form, which is not only is reality stranger than we suppose,

00:50:11.200 it's stranger than we can suppose. By giving a deflationary account of our notion of space and time,

00:50:18.280 you are saying, whatever this mapping is between appearance and reality,

00:50:22.460 we are so ill-equipped to talk about it based on this interface analogy that it is, on some level,

00:50:32.600 far stranger and far more foreign to the way in which we're thinking about things than anyone has.

00:50:41.140 So your claim isn't actually, so I'm just trying to get at what is truly novel about your claim.

00:50:47.700 One thing that's novel is the expectation that evolution has selected for some approximation to what is true

00:50:56.880 seems false, right? So fitness trumps truth. And as a result, whatever this mapping is to underlying reality,

00:51:08.340 we are in a far greater state of ignorance about it than most people expect.

00:51:13.440 That's right. Absolutely. You've nailed it on the head. And I would say this, that it's the relationship

00:51:19.600 between a visualization tool and whatever it is that we're visualizing, right? So there's going to be

00:51:26.680 this objective reality that's out there. And evolution just gave us this very, very dumbed down, 0.80

00:51:32.860 species-specific visualization tool. The very language of that tool is probably, I mean,

00:51:37.580 the whole point of a visualization tool is to hide the complexity of the objective reality and just

00:51:43.520 give you, you know, a dumbed down tool that you can use. And so the very language of space and time

00:51:50.460 and objects is just the wrong language for whatever the thing is. Just like-

00:51:53.520 I would say, though, that, you know, as far as I understand, most up to this point,

00:52:00.080 I know we're going to talk about consciousness soon and then we'll get into a different realm,

00:52:03.340 but up to this point, everything that you've just said, I think most physicists would agree with and

00:52:09.540 is part of the conversation in quantum mechanics right now. And many physicists are talking about

00:52:17.400 this problem of space-time and of space and time independently as well, clearly not being

00:52:26.340 the final answer to what is fundamental. And everything we see out of quantum mechanics

00:52:34.420 gives us a real philosophical problem similar to the one you're describing, which is it seems that

00:52:42.200 the fundamental nature of the universe, what the universe is actually made of, is not anything

00:52:48.560 like what we experience it all the way to the point of space and time.

00:52:52.940 That's right. And so it's really interesting because if you look at our biggest scientific

00:53:00.160 theories in physics, general relativity and also special relativity are about space-time, right?

00:53:09.420 Space-time is assumed to be an objective reality and a fundamental one. In quantum field theory

00:53:15.140 as well, the fields are defined over space-time. And so physics, as Neymar Arkani-Hamed has put it,

00:53:25.740 and he's a professor at the Institute for Advanced Study at Princeton, he's pointed out that for the

00:53:30.580 last few centuries, physics has been about what happens in space-time. But now they're realizing

00:53:39.720 that to get general relativity and the standard model of physics to play well together, they're

00:53:45.820 going to have to let go of space-time. It cannot be fundamental. And he's not worried about it.

00:53:50.560 And in fact, he says most of his colleagues agree that space-time is doomed and there's going to be

00:53:55.480 something deeper. And that's wonderful because we're about to learn something new. There's a deeper

00:53:59.800 framework for us to be thinking about physics and space-time will have to be emergent from that deeper

00:54:06.300 deeper framework.

00:54:07.560 I actually, I watched a lecture of his recently and I wrote down this short quote. He says,

00:54:12.500 all these things are converging on some completely new formulation of standard physics where space-time

00:54:17.640 and quantum mechanics are not our inputs but our outputs. And I thought that was very well said.

00:54:23.180 But that, so as far as I, you know, understand where physics is at at this point, I think all of

00:54:30.600 these physicists would agree with you up until this point. And I think now we can probably cross over.

00:54:37.040 Although I would just point out that they might agree for different reasons, right? They're not

00:54:41.500 using the same evolutionary logic.

00:54:44.420 But that there's nothing intrinsic in what Don is saying about how false our view of the fundamental

00:54:52.460 nature of reality is. That it is that. That you can actually take it all the way to space-time

00:54:58.300 and that we're probably wrong in all of those assumptions about what we think.

00:55:03.520 I agree. And I think it's really interesting that the pillars of science are all saying the

00:55:09.440 same thing. Evolution by natural selection is saying you need to let go of space-time. And then

00:55:14.320 the physicists trying to get general relativity and quantum field theory to play, right, they're

00:55:18.180 saying you have to let go of space-time. When our best science is saying that, it's time for an

00:55:22.300 interesting revolution. That's going to be fun. I mean, it's going to be very exciting to see what happens

00:55:26.340 when we go behind space-time. It's so counterintuitive though, right? We've just assumed

00:55:31.320 that, I mean, our story is space-time came into existence 13.8 billion years ago at the

00:55:37.080 Big Bang. It was the fundamental reality. We're saying there's a deeper story. That story

00:55:42.680 is only true up to a point. There's a much, much deeper story. And that's more like an interface

00:55:50.380 story. That's the projection of a much deeper story we're going to have to find. And that

00:55:54.620 is tremendously fun.

00:55:57.200 Yeah, well, so we're now going to move on to consciousness, which will be interesting. I

00:56:01.700 just, I guess, I want to flag my lingering concern that your rationale, if taken in deadly

00:56:10.440 earnest, may still kick open the door to epistemological skepticism, for me at least. Because

00:56:16.940 I think, you know, if one space and time are dispensed with causality and kind of an evolutionary

00:56:24.080 rationale does, I mean, this is kind of the Plantinga argument you referred to. It's just

00:56:30.340 once you start pulling hard at those threads, I'm not sure how much the fabric of epistemology

00:56:35.940 can be defended.

00:56:37.680 I agree with you, Sam, in the following sense. I think that it might actually go that way

00:56:43.160 just on the evolutionary arguments alone. So what I'm going to want to do is to, whatever

00:56:48.120 the deeper theory of reality that I propose, it needs to be such that it will not fall

00:56:52.280 into the epistemological problems that you're raising. So the deeper theory needs to avoid

00:56:57.480 those epistemological problems and show why that deeper theory looks like evolution by

00:57:03.600 natural selection when we project it into our space-time interface. In other words, so that

00:57:08.260 these kinds of problems might arise because evolution by natural selection itself is not

00:57:12.640 the deepest theory. It's just an interface version of a deeper theory.

00:57:16.480 Right. Okay.

00:57:17.800 Yeah. So on this topic of causality in time and whether this project even makes sense, which

00:57:24.400 as I know is a place you and I have gotten to before in our conversations, when you say things

00:57:29.320 like the brain and neurons are not the source of causal powers and that we need to find another

00:57:35.520 source. My question is, why would you assume that there are causal powers at all in the fundamental

00:57:43.060 nature of reality? So it's not clear to me why we include causal powers as part of a fundamental

00:57:50.460 reality if space-time doesn't exist.

00:57:53.240 I don't quite see how there is causality without time, at least in the way that we typically think

00:57:59.560 about it.

00:58:00.360 I mean, just to take an example, which is kind of standard physics, although often neglected,

00:58:05.900 the notion of a block universe, right? The notion that the future exists just as much as the present

00:58:11.320 as the past. And so there really are no events. There's just a single datum, which is the entire

00:58:19.200 cosmos, right?

00:58:20.000 And its connections.

00:58:21.240 So causality under that construal is really an illusion.

00:58:26.880 That's right. And without endorsing the block universe view, I would say that causality in space

00:58:35.460 and time is a fiction. It's a useful fiction that we've evolved in our interface. But that strictly

00:58:42.880 speaking, causality in space and time is not, because space and time is not the fundamental

00:58:49.360 reality, the appearance of causality, like my hand pushing this glass and moving it, it gives the

00:58:54.860 appearance that my hand has causal powers and is causing the glass to move. But in fact, that's just a

00:59:01.980 useful fiction. It's like if I drag an icon on my desktop to the trash can and delete the file. It looks

00:59:08.540 like the movement of the icon on the desktop to the trash can caused the file to be deleted. Well,

00:59:14.140 for the casual user, that's a perfectly harmless fiction to believe. If you move the icon to the

00:59:19.960 trash can, it causes the file to be. It's perfectly harmless. But for the user, for the guy who actually

00:59:25.100 wants to build the software interface for this, go under the hood, that fiction has to be let go.

00:59:30.580 So I'm claiming that within space and time, all the appearance of causality is a fiction. Now,

00:59:38.820 in terms of a deeper theory, because you're asking in a deeper theory, what about causality there?

00:59:42.420 Well, my argument is that causality is part of the illusion of time. Assuming time is some sort

00:59:48.640 of illusion and time is not fundamental, at least as far as we usually talk about. I mean, I can think

00:59:54.160 of, this is another conversation of how we can almost redefine causality, which in my view, I have.

01:00:01.380 I think there's a way to talk about different things being connected. But in terms of the way

01:00:06.640 we, our definition of causality and how we use it, it is dependent on time. It is a part of things that

01:00:12.300 play out in time. You need something, you need something to happen in the past to cause something

01:00:18.240 to happen in the future. It is this direct relationship in time. And so I don't even know

01:00:25.460 how you would talk about causality without time. It needs time for its own definition.

01:00:32.260 So I think if we're redefining causality, which I think is kosher, actually, I think that's something

01:00:36.540 we can talk about. I've never been clear whether that is what you mean. Are we kind of redefining

01:00:41.880 what causality is? And is it more like connections between things rather than one thing happens and

01:00:50.080 then another thing happens in response? Yeah. I would also add another aspect here,

01:00:57.080 which is that the notion of possibility may be spurious, right? So that it may in fact be that

01:01:03.980 nothing is ever possible. There's only what is actual, right? There's only what happens.

01:01:10.360 And our sense that something else might have happened in any circumstance, that just might

01:01:16.380 be a, again, part of this user interface that has seemed useful because it is useful to try,

01:01:23.300 like when we're apparently making decisions between two possibilities and we need to model

01:01:28.200 counterfactuals, right? Counterfactual thinking is incredibly useful. And yet, what if it is simply

01:01:33.340 the case as it, you know, as it would be in a block universe that there's just, you know,

01:01:38.180 the novel is already written and you're on page 75, but page 168 exists already in some sense.

01:01:46.200 And I also, I don't think you need the block universe though, because I think there's just 0.94

01:01:49.700 one way of getting at the point. Yeah. I mean, it's a good visualization,

01:01:52.260 but I think most physicists will have some argument about it being described that way. But I think the

01:01:57.660 analogy holds, and I was just reading Carlo Rovelli's book on time, and he makes this point as well, that at a

01:02:08.420 certain level, there is no difference between past and future. And essentially, I mean, his thesis in the

01:02:14.640 book is that time is an illusion. It is not something... So, sorry, go ahead.

01:02:21.680 So, yeah, I think that we'll need a notion of causality that's outside of space-time,

01:02:27.020 that is not going to be dependent on time. It'll be more like relationship, as you talked about.

01:02:33.020 And in terms of the counterfactuals and possibilities, I think we'll want to have a

01:02:39.700 conversation about probability and how we interpret probabilities in scientific theories.

01:02:45.120 whether they're... I mean, so there are probabilities that are epistemic in the sense that maybe there's

01:02:51.200 a deterministic reality out there, and I just don't know enough about it. So, the probabilities

01:02:56.900 are subjective. It's my lack of knowledge.

01:02:59.480 There's frequency, but our sense of probability may be spurious.

01:03:04.180 That's right. But then, if there are probabilities in which, no matter how much my knowledge increases,

01:03:11.380 the probability will not disappear. And so, we often call those in science objective chance.

01:03:18.520 And I think we'll want to have a conversation about how we think about probabilities and objective

01:03:23.940 chance. It will actually take us into the question about free will and so forth, my version of notions

01:03:30.540 of free will versus determinism. So, I think that that's going to be an interesting conversation.

01:03:35.080 So, I agree that we need a notion of causality that transcends time, and I'm proposing one.

01:03:42.780 By the way, it's interesting. I know you...

01:03:44.060 Yeah, go ahead. Sorry.

01:03:44.940 You talked with Judea Pearl, and he's got, of course, these directed acyclic graphs,

01:03:50.660 models of causal reasoning, which are brilliant, and they've actually given us a mathematical science

01:03:55.200 for the first time of causal reasoning.

01:03:57.700 But when, you know, in his book, Pearl doesn't define causality. He refuses to define the notion

01:04:05.900 of causality. In some sense, what we're facing here is that every scientific theory, and this is

01:04:12.920 a really important idea, I think. No scientific theory is a theory of everything. There's no such

01:04:18.840 thing. Every scientific theory makes certain assumptions. We call them the premises or the

01:04:24.680 assumptions of the theory. And only if you grant the theory those assumptions can it go and explain

01:04:30.600 everything else. And so, we're going to have, in every scientific theory, certain primitives that

01:04:37.380 are unexplained. They are the miracles vis-a-vis that theory. Now, you may say, well, I can get you

01:04:44.560 a deeper theory for which those assumptions come out as consequences, but you will have a deeper set

01:04:49.700 of assumptions.

01:04:50.640 There's going to be an axiom somewhere at the bottom.

01:04:52.460 Absolutely. And that's a humbling recognition for a scientist, to realize that we will never

01:04:59.220 have a theory of everything. We will always have a miracle or a few miracles. We want to keep them

01:05:05.020 as few as possible.

01:05:06.100 I don't like that you call them miracles. I would like to have the record show.

01:05:09.860 I understand that. But we call them assumptions.

01:05:12.560 Why not call them axioms? Yeah.

01:05:14.660 Well, because I want to really make the point...

01:05:16.540 It's another place where I think people might actually be confused about what you mean,

01:05:19.660 which is why I'm...

01:05:20.780 Sure. I'm glad that you're pushing back.

01:05:22.320 I'm trying to protect you.

01:05:23.440 Right. So, I'll just say that there are things that the theory cannot explain.

01:05:28.660 And there will always be things that every scientific theory cannot explain, and it's

01:05:33.260 a principal problem. So, the interesting thing will be, in a deeper theory, will we have

01:05:38.900 something that's like a causal notion that will be a primitive of the theory? And it may not

01:05:43.780 be dependent on time, but it'll be... There will be primitives, and an explanation will

01:05:49.100 stop.

01:05:49.400 I guess. So, my question, my issue really is, why use the word causality when you're speaking

01:05:56.340 in more fundamental terms? So, why not say something like, connections, relationships,

01:06:01.840 to me, seem much more, much closer analogies. And so, to say, what we view as causality is,

01:06:07.960 in fact, something more like a connection or a relationship at a more fundamental level.

01:06:12.900 I'm completely on board. I agree with you completely. I think a deeper theory, we may

01:06:15.620 think that the term causality is just not a very useful term anymore. It was useful in space and

01:06:21.000 time. And connection or influence is a better term at a deeper level.

01:06:26.320 Okay. So, on to consciousness and free will and other dangerous topics.

01:06:31.080 Yes.

01:06:31.260 What, in your view, is the connection between consciousness and the base layers?

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Making Sense - Sam Harris - December 11, 2019

#178 — The Reality Illusion

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