brettcap

00:00:19.500 And I wondered what to call today's episode, because what I'm kind of doing is reacting to a making sense podcast.

00:00:54.800 So I thought like, popularly in reacts to Sam Harris or Brett all destroy Max Tegmark something like that.

00:01:10.000 And really, when I thought about what I was doing, it wasn't so much a reaction to what Sam Harris was saying or what Max Tegmark was saying.

00:01:23.500 It allowed me to explain the differences between what I regard as more or less mainstream philosophical views on these particular things.

00:01:32.000 And what I hear at Topcast explain, which is a version of Perperina epistemology, a version of the way in which David Deutsch explains the world.

00:01:42.400 But of course, I cleave most closely to what is explained in the fabric of reality in the beginning of Divinity amongst other things.

00:02:08.800 And the more I thought about it, the more I thought I can get a series of podcasts out about all of this stuff.

00:02:14.200 The M's mathematics, morality, metaphysics, minds, multiverse, misconceptions, mistakes about the material world and many worlds in the modern world.

00:02:37.800 But we have so much else to cover, I just doubt we'll get to membranes and those mysteries bordering on magic.

00:02:44.100 Ostensibly, as I say, this is a reaction podcast, a reaction to Sam Harris and Max Tegma talking for the first time on making sense.

00:02:55.500 But really, as I say, it's just an excuse for me to talk about these issues prompted by what they say there.

00:03:04.500 So for example, in this first episode, which is an hour long or so, I can tell you the ratio, it's approximately 15% of those two guys, Sam and Max and 85% me.

00:03:13.900 And in this first episode, actually, of the series, I've only got through about the first 18 minutes or so of their original podcast.

00:03:28.400 And it's going to take the first part of that second podcast, which is largely about AGI and of course I'm going to say,

00:03:35.400 there are serious fundamental misconceptions in the worldview of Sam and Max when it comes to AGI and issues around AGI.

00:04:04.400 I've got the physical book while I should say Kindle version of the book and the audio version of the book.

00:04:12.900 Both of David Deutsch's interviews appear as number one and two of his selected interviews for the making sense book.

00:04:26.700 I think the two most interesting people that are interviewed throughout that entire book, the series of interviews is certainly David and Max.

00:04:35.900 And of course Sam has an M&E's name and Max has an M&E's name as well and I'm going to be playing a little music today.

00:04:56.300 And I feel as if I agree when it comes to things on the multiverse and aspects of philosophy that I'm agreeing with the general

00:05:20.400 What struck me in the interview, and this is not so true of Max's books on the topic and articles on the topic,

00:05:27.500 because he, his big thing is talking about levels of the multiverse, different versions of the multiverse.

00:05:32.500 Well, in this interview, he gives with Sam Harris, where he spends a lot of time talking about the multiverse.

00:05:37.100 Well, the one kind of multiverse that he doesn't talk about is the quantum multiverse, which is really, really bizarre.

00:05:59.400 It's just the universe beyond what's observable, but we know that there is something beyond the observable universe.

00:06:08.900 When I say there, I mean, Sam and Max seem to agree about something to do with the unobserved and the unobserved is somehow

00:06:19.100 I don't know who these others are, these are empiricists, but no one seems these days much to answer to the title of empiricist.

00:06:25.400 But what they get wrong and we'll hear this is that they seem to think that things which are not observable are, therefore not popularion, but this is wrong.

00:06:36.900 Okay, this is this is seriously wrong as we will come to a theory which is in principle, not testable is not science.

00:06:49.000 Well, only a certain breed of theoretical physicists get really upset if you start to say things like what you're doing there.

00:07:06.800 It's metaphysics, which is still really worthy and interesting and good to do and they get very, very upset.

00:07:29.000 Things like one of Max's multiverse's, namely his level four multiverse, which is the multiverse of universes where those other universes have different different laws of physics.

00:07:42.600 All the universes obey exactly the same laws of physics, namely they come out of our understanding of the quantum laws of physics.

00:07:54.600 That's the universe that obeys all other possible different kinds of laws of physics and David Lewis first thought about this.

00:08:02.500 If you like these are the logically possible other universes, logically possible, not merely physically possible other universes, which is what the quantum multiverse is, those universes that are permitted by the existing laws of physics.

00:08:15.700 Now, if there are places out there in reality beyond our physical reality, then they would obey, presumably other laws of physics.

00:08:25.000 And if all such other laws of physics are instantiated somewhere out there, then we have all logically possible universes out there somewhere other.

00:08:32.300 And David Lewis first had this, why do I think he first had this idea, but he certainly wrote the book on it.

00:08:37.400 And we call this idea the plenitude. So the plenitude is a much larger class of universes of different physical realities than the mere ever read a multiverse, vast as that is.

00:08:57.700 Let me just give you a quick rundown. He's got level one multiverse, which as I say, I wouldn't regard as being a multiverse. It's just the universe where the universe means we have this region of space that we can observe.

00:09:10.500 And we know that beyond what is observed as a matter of cosmological fact is just a small portion of the entire physical universe, all bang the same laws and all spatially continuous in somewhere other.

00:09:28.900 So that's that. His second kind, his level two multiverse. Well, this is perhaps at the big bang what happened was that during the inflationary period there were lots of other bubble universes created with different slightly different initial conditions, but obeying the same laws of physics.

00:09:47.100 So you have this proliferation at the big bang of many simultaneous big bangs going off and lots and lots and lots of different universes been created in parallel, but we don't have access to those other universes.

00:09:59.800 I'm not actually aware of any experimental test that has been proposed that would allow us to even in principle access observations that would allow us to rule out the single universe theory or the many universes theory in that sense.

00:10:14.500 That kind of multiverse and so therefore it sits at the moment in the realm of mathematics or metaphysics it's not physics and it's not physics by the measure we say that well you can't test it there's no experimental test yet now I could be wrong about that someone clever might have thought of an experimental test.

00:10:29.900 Now in fact there were observations going back a decade or more that suggested that we might have been able to observe these other universes with different initial conditions or perhaps even subtly different laws.

00:10:42.900 And well the observation went like this if if beyond the horizon of what we could see let's say the constants of nature were different then you would be able to observe that change in the constants of nature in a different universe far away from where we are.

00:10:57.300 And so a group of scientists among them at the University of New South Wales have been talking about the University of New South Wales a little bit recently, but led by Professor John Webb and his colleague Michael Murphy now professor of astrophysics down at Swinborn University.

00:11:12.300 These guys using among the largest land based telescopes reflecting telescopes on earth in Hawaii, the Keck telescopes they were looking at a lot from very distant quasars that passed through very distant galaxies and along the way got absorbed and changed and whatever else and they looking at the spectral lines and the spectral lines they looked at they thought had changed in some way were different to the ones in the laboratory here on earth now correcting for redshift and all that sort of stuff correcting for everything.

00:11:41.700 They still found a change and the explanation for the change was this thing called the fine structure constant had changed.

00:11:49.100 And if the fine structure constant change because it's made up of Planck's constant and the charge on an electron and the speed of light so you've got these fundamental constants coming together to make up the fine structure constant.

00:12:01.100 If the fine structure constant had changed one or more of these other fundamental constants must have changed but it's very hard to tell which one it would have been now whatever the case if the fine structure constant has changed in a different region of the universe very distant from where we are then that seems to suggest it is literally a different universe that you're seeing you're seeing some other region of space.

00:12:21.300 A bang subtly different physical or so perhaps by that measure we would be able to see another universe and that would make such a kind of multiverse testable in that sense now in reality of course looking at this whole issue from a period perspective what they did was make a measurement of the fine structure constant and then.

00:12:42.540 Concluded the fine structure constant is the thing that's changing but they published all the results and they seem to repeatedly find no matter how often they tested this and how many other groups also tested this they all seem to converge on yes the fine structure constant seem to change only a very, very tiny amount but one can imagine looking still further with more powerful telescopes and see even more of a change so perhaps the fine structure constant the constant the universe are what they are here around us but as you get further away closer to other universes.

00:13:17.980 Well, as we say here in preparing a epistemology it could be the case the fine structure constant is changing or it could be the case that you've made an error with your measurements and yes it turned out there was a systematic error there was a systematic error with the measurements so we were all very disappointed.

00:13:36.540 But still they had these really interesting techniques it's just that there was a issue with the mirror or something as far as I know from these cake telescopes that anyway I don't fully understand exactly what it was all I know was their measurements of the change the fine structure constant turned out to be null and void there was no such change so.

00:13:53.740 Yes this method of seeing other universes has failed and there's no good explanation there's no good explanation of being able to.

00:14:01.580 Use such a method to actually physically see if you like other universes by seeing changes in constant nature we should expect if we do see changes in the constant nature that what we're actually seeing is errors in the methodology errors with the instrumentation that kind of thing so we have no way of.

00:14:20.300 Knowing knowing in the perperience and having a good explanation that there really do exist these other universes out there with different physical laws or that they really do exist these other universes bubble universes out there that started with different initial conditions.

00:14:36.580 But we do have a good explanation of the level three multiverse as Max calls it the ever read in multiverse we know that one exists because it's the only known explanation of what we observe in quantum theory and the equations of quantum theory and all that kind of thing.

00:14:50.340 So they're the four one the observed universe and the parts of the universe that are beyond the observed horizon the level two multiverse the bubble universe is the also began supposedly at the big bang with slightly different initial conditions but a bang the same laws the level three multiverse the ever read in multiverse.

00:15:06.420 Where everything abays the same physical laws but you're constantly getting differentiation of those universes and then last of all all the logically possible universes that could exist with different physical laws completely or not so completely but all possible physical laws are represented out there somewhere other now as I say the first of those is just the universe so that's fine that counts as science and number three cancer science but.

00:15:30.420 Two how do we observe these things and four how do we observe those things well no way known yet but again you hear some theoretical physicists talk and they get very upset they know very touch you about being told that this doesn't quite qualify science this is no insult though in the

00:15:47.700 Paparian framework Papa zone work you know epistemology is not science it's non science and that's fine it's totally fine the other one majority of people on planet earth aren't doing science but they're doing important work so why people get upset why physicists only physicists get upset when they're told well that's not experimentally testable just yet if you can think of a clever experimental test that would allow us to in some way access those other universes great then you've got an experiment so you're back within the realm of science that's the whole point of.

00:16:16.700 A science is to be able to do two things at once to come up with the creative idea yes to to think of the new explanation the new theory that's great.

00:16:25.700 And to also think of how we might go about testing this in the real world to rule out competing theories but if you can't rule out competing theories like well there's only one universe and it's the one that we're able to observe.

00:16:39.700 Then well I'm sorry you're not quite doing science now they can call it science if they want that's fine I'm not overly worried that certainly the next closest thing to science right this metaphysical discussion about other universes with different physical laws I would say it's right next door to science it is the next closest thing and.

00:16:57.700 I can imagine that one day someone will think of some interesting way in which we might experimentally test for something like that you know I can imagine a distant future gravitational wave thing and that the text gravitational waves and the only explanation of the particular pattern of gravitational waves would be if at the big bang other universes were being produced perhaps even other universes with different physical laws I can imagine some distant future someone thinking of something like that but they haven't thought of it now.

00:17:26.700 So let's get into listening to some of the discussion between Sam and Max and I'll pause it at various points and as I say I'm just small snippets today just picking out small snippets of the conversation and just reacting to it and it'll give me an opportunity to discuss what proper might have said about this kind of thing and what I think that science says about all of this stuff at the moment what our best epistemology would say about.

00:18:00.700 Start there kind of at the foundations of our knowledge and the foundations of science because you know in science we are making our best effort to arrive at a unified understanding of reality and I think there are many people in our culture many and

00:18:27.700 I think there's no view of the world that encompasses subatomic particles and cocktail parties and everything in between but I think that from the point of view of science we have to believe that there is.

00:18:40.700 We may use different concepts at different scales but there shouldn't be radical discontinuities between different scales and our understanding of reality and I'm assuming that's an intuition you share but let's just take that as a starting point.

00:19:02.700 So I regard myself of course as a realist and as a scientific realist but I do think there is a difference between science and non science and Sam wanted to say there that there should be a scientific understanding of everything from the very smallest through to cocktail parties through to the very largest.

00:19:20.700 Now in a sense this is right so long as you're just talking about the physical stuff but we know that there is also abstract stuff and there is a distinction and I think Sam gets this later on in the conversation certainly in his second conversation with Max where he talks about the distinction between software and hardware.

00:19:38.700 I don't know really if he has a clear idea in his mind as to what that difference is but what we say here is that there is a difference between physical stuff and abstract stuff and the abstract stuff can have an effect on the physical stuff.

00:19:53.700 Now it's via physical forces obviously but the difference is and where this radical discontinuity does come in which Sam doesn't think it exists but I would say there is there is a radical discontinuity is where knowledge is created where you have inherently unpredictable stuff.

00:20:12.700 But within physics and within the physical sciences we can have predictions we can have quite precise predictions. So long as they are carefully controlled but once you get into the realm of human affairs it's not merely because certain problems are intractable.

00:20:27.700 But there are in principle not predictable because they are acts of creation creating knowledge is an act of creation it wasn't there before it could not possibly have been predicted before and then it was created now how we don't know we don't yet know exactly how this creativity works we simply know it exists.

00:20:45.700 And this is true of lots of things in science all the time we have this phenomena we don't quite understand but we know that it's there we know that it's real we yet to have a full understanding of it and there won't be a full understanding of course in our

00:20:57.700 opinion view and I would say that on the side of people who don't regard themselves as per periods and as we will see here I would say one reason that people don't regard themselves per periods is that understand what poppers epistemology is.

00:21:18.700 It encompasses all of a period epistemology we know that's not true but if they think that that's what they think then they're apt to think that science is just this all encompassing thing and that anything that is non science is therefore not rational.

00:21:32.700 To begin with the same wants to bring everything within the scientific world view in that sense now it's fine to have a rational world view.

00:21:41.700 They will view govern the by reason but at the same time to notice that there are differences in methodologies and to have names for these differences in methodology and not to make value judgments about these differences in methodology just to recognize they're real not everything is mathematics and mathematics is not science therefore science is not everything.

00:22:01.700 These things are different morality is not science science makes claims about everything it's universal but so too can epistemology make claims about everything but these are importantly distinct ways of coming to understand the world because they use different methodologies and we just got names for these but in certain moods we hear Sam kind of suggesting something like well science just is knowledge.

00:22:29.700 It just is knowledge just if you can know stuff then that science that seems to be the the way he's hinting at stuff and that if you claim that something's not science then what you're saying of that thing is it's unreasonable or rational or something else like that.

00:22:43.700 And we just don't think that there are parts of reality that are not amenable to a scientific understanding our best way in is not to understand that thing scientifically.

00:23:01.700 These things won't contradict science but a different two science by the measure that he in science we have this method of criticism that we call the experimental test.

00:23:11.700 And that experimental test the experiment distinguishes science from other stuff mathematics is distinguished by this method of proof.

00:23:20.700 Now it's not only in mathematics that you have proof but it is distinguished by that it's one of the techniques that really is in mathematics and perhaps in logic as well and in argumentation of course.

00:23:32.700 But our scientific understanding of proof is to say it's a physical process and in fact we're going to get to that because I think that this is one area of Max's worldview that doesn't quite correspond to what we understand reality is according to.

00:23:47.700 David Deutsches understanding of the mathematicians misconception this idea that mathematicians have privileged access to reality in some way.

00:24:19.700 Then other people get upset and say you know if you think gravity is a social construct and encourage you to take a step out through my window here on the sixth floor and if you drill down into what this conflict comes from it's just that they're using that our word reality in very different ways.

00:24:34.700 And as a physicist the way I use the word reality is I assume that there is something out there independent of me as a human.

00:24:48.700 And then we take this very humble approach of saying okay there is some stuff that exists out there or physical reality.

00:24:55.700 Let's call it and let's look at it as closely we can and try to figure out what properties it has if there's some confusion about something you know that's our problem not reality's problem.

00:25:07.700 There's no doubt in my mind that our universe knows perfectly well what is doing and it's it functions in some way.

00:25:13.700 We physicists have so far failed to figure out what that way is and we're in this schizophrenic situation where we can't even make quantum mechanics talk to relativity theory properly.

00:25:24.700 But that's the way I see it simply a failure so far in our own creativity and I think it's not only would I guess that there is a reality out there independent of us, but I actually feel it's quite arrogant to say the opposite.

00:25:39.700 Because it sort of presumes that we humans play to go center stage solipsists say that there is no reality with that themselves ostrich is in the apocryphal story right make this assumption that things that they don't see don't exist.

00:25:56.700 But even very respected scientists go down this sleeper slope sometimes but I think that's very arrogant and I think we can use a good dose of humility.

00:26:19.700 I broadly agree with all of that, that's a rational defensive realism. This is arguing against those relativists not many people actually self-identify sure a lot of this, but you do get this impression sometimes that people want to say well science has no privilege access to explaining the physical world.

00:26:38.700 It's just people engaging in narratives these are stories these are fictions they're not really uncovering truths about reality the explanations aren't necessarily objective this is just a certain way of explaining things that isn't privileged.

00:26:53.700 I think all that's wrong and I think Max's defense of that is all quite right and there's a sense in which that is a kind of arrogance, but I would just maybe in this is where I'm of course splitting hairs is where I'm core of course nitpicking.

00:27:08.700 I would say that humans are center stage in a sense we are we are the only known system in the entire observable universe that we've ever known about that can model the rest of reality.

00:27:27.700 I think to have this self-similarity with the rest of the universe it's coming to resemble in certain ways the rest of physical reality and that's a wonderful thing that does put us at the center, the center of understanding it might be the only such place in the universe where the universe is understanding itself and so in that sense we've got every right to be arrogant not arrogant in the sense that we will come to a final understanding or arrogant in the sense that we can't possibly have any understanding and there's that arrogance of solipsism of not possibly being able to

00:27:56.700 be saying of other people you can't understand anything either. Okay that that arrogance that we can rule that out as a bad explanation but the arrogance of yeah we are really special.

00:28:07.700 We are so far as we know entirely unique in being able to do this stuff that we can do to explain everything to gain control over time of everything.

00:28:17.700 I'm happy to put my hand up to that arrogance and I think we should we could do with a little bit more of that kind of arrogance and less of the humility of thinking that we can't or shouldn't.

00:28:27.700 So that's the splitting hairs minor difference I would have in emphasis between people who want to argue against relativism in that way and say well the relativists are wrong the solips are wrong I agree with them so far so good.

00:28:41.700 But when they then turn around and say well we shouldn't be arrogant we should have this humility now yes there's a humility of saying we don't have all the answers so we can't be arrogant that way but nonetheless not being so humble as to say we're not unique and special and powerful and all of that kind of thing and we can gain more power over time over the universe and that's a good thing let's keep going.

00:29:07.700 In conveniently for us this skepticism about the possibility of understanding reality does sort of sneak in the back door for us somewhat paradoxically by virtue of taking

00:29:23.700 science seriously in particular evolutionary biology seriously and this is something you and I were talking about when we last met where you know I think at one point the conversation I observed as almost everyone has who thinks about evolution that one thing we can be sure of is that that our cognitive capacity is in our common sense and our intuitions about reality.

00:29:46.700 We have not evolved to equip us to understand reality at the smallest possible scale or the largest or things moving incredibly fast or things that are very old that we have intuitions that are tuned for things at human scale things that are moving relatively slowly and we have to decide whether we can mate with them or whether we can eat them or whether they're going to eat us.

00:30:10.700 And so you and I were talking about this and so I know I said that it's no surprise therefore that the deliverances of science in particular your areas of science are deeply counterintuitive and you.

00:30:24.700 You did me one better though you you said that not only is it not surprising it would be surprising and in fact give you reason to mistrust your theories if they were aligned with common sense we should expect the punch line at the end of the book of nature to be deeply counterintuitive in some sense and I just want you to expand on that a little bit.

00:30:51.700 Of course I think that's kind of wrong kind of wrong there's this idea that we have these evolved intuitions and indeed evolved common sense but I don't think that's true.

00:31:04.700 I think we learn what's called common sense over time we learn certain kind of intuitions there might be some that are inborn granted granted but what's not inborn is newton's physics but people who try and learn newton's physics tend to understand the three laws of motion pretty quickly an object emotion states emotion and less acted on by an external force moving in a straight line.

00:31:28.700 People get it but back in Aristotle's time that wasn't regarded as being true or being common sense the common sense thing was any moving object eventually comes to a halt that was common sense now how do people come to this common sense what is common sense.

00:31:44.700 Is it common sense that a moving object eventually comes to a stop or is it common sense that a moving object will just continue moving indefinitely and less acted on by a force which one's common sense.

00:31:54.700 Well I don't know which one is common sense but I know that we need to learn both perhaps the first one is kind of learned by infants experimenting in the world or not I don't know I just can't remember what I used to think before I understood well it's actually Galileo's law but this idea of moving objects

00:32:12.700 keep moving until acted on by force. What I'm saying here is that I don't think that this idea this is a Dawkins idea of middle world that we've evolved with a capacity that limits our ability to understand the world.

00:32:25.700 What we've in fact evolved with in fact is a brain which has the capacity to explain everything to have this universal capacity for understanding the world.

00:32:36.700 This is what David Deutsch explains in the beginning of infinity there isn't some limit set by evolution of that kind of understanding of being impossibly unable to overturn your common sense or your intuition your intuitions can change with what you learn about reality.

00:32:56.700 My intuitions used to be that you could come to certain knowledge you could get the final answer that was my intuition now my intuition is you can't do that it's exactly the opposite I've my intuition has changed my common sense has changed I think this is true of everyone and so people make a big deal of this are we've got an evolved brain yeah we do have an evolved brain therefore it's limited in what it can understand no no you've misunderstood computational university and misunderstood explanatory universality.

00:33:25.700 This is what the brain is what the human mind is capable of doing but people make a big deal about this so they make a big deal about how people just can't understand quantum theory it's really hard or string theory it's really these things are new these things are really new on the scene.

00:33:43.700 In the distant future will have better ways of understanding these things especially if they comport with reality.

00:33:49.700 I have no doubt that in generations from now people regard quantum theory and roughly the same way as we regard Newton's theories now.

00:33:57.700 It used to be thought that Newtonian physics was completely counterintuitive it took a long time for the general public to understand this stuff so now routinely you know kids in sort of the first year of high school learn the basics of Newton's physics.

00:34:12.700 They do one day non-coursively we'll be educating our you know new teenagers if they're interested or even younger is the basics of quantum theory.

00:34:21.700 But whatever the success of the quantum theory is because we will know how to do that we will know how to do it but there is this thought that well it's just mathematically too complex.

00:34:31.700 But we don't need all the idea in order to understand the basics of Newtonian physics you don't need to go down the road of being able to solve the three body problem for example.

00:34:41.700 Okay yeah that's technically difficult but the the basics the basic ideas that can be understood that can be understood by people if they take an interest and you can understand anything the more interest you take in it the more time you spend trying to understand that thing.

00:34:55.700 And the fact that one person can do it means that someone else can do it the string theory that Ed would wouldn't understand could be understood by anyone else if they took an interest but they tend not to take an interest in these things.

00:35:08.700 And I understand this is an extremely poorly subscribed notion but all it is is a consequence of thinking of the mind as a universal explainer.

00:35:20.700 That doesn't mean that any one person will explain everything all have the capacity to explain everything even everything that's known because they will never take an interest in everything that's not.

00:35:35.700 Now what causes someone to take an interest well add so I think that's an open question you know why do some people find certain things inherently boring.

00:35:43.700 And when they regard these things as inherently boring we say well I say the culture says they physically incapable of knowing nothing of understanding that thing you know certain people are just physically unable to learn maths or something like that a certain kinds of maths it's it's too hard for them.

00:36:00.700 Rather than saying it's too boring for them now a lot of people would just pull the straps there and say well maybe they're the same thing.

00:36:07.700 Maybe they're the same thing too hard or too boring. What I'm saying is that in theory given the right explanations they could understand those things curiosity is a real thing trying to solve a certain problem you need to have the that problem situation we say this is part of

00:36:23.700 theory and epistemology of course I part of papier in epistemology that almost no one except the papierians actually know so when people describe papier in epistemology and then not papierians and hear them talking about problems situations.

00:36:36.700 And that's it and that's what we're going to hear later on okay let's go back and we'll hear the next thing that Max has to say about this on this idea that the evolved brain is an evolved to understand the nature of reality or sophisticated physics or something like that.

00:37:00.700 Yeah that's exactly right I think that's a very clear prediction of Darwin's ideas if you take them seriously that whatever the ultimate nature of reality is it should seem really weird and counterintuitive to us because you know developing a brain advanced enough to understand new concepts is costly in evolution.

00:37:21.700 And we wouldn't have evolved it and spent a lot of energy increasing metabolism etc if it didn't help in any way if some cavewoman spent too much time pondering what was out there beyond all the stars that she could see or subatomic particles.

00:37:38.700 But she might not have noticed the tiger that snuck up behind her and gone clean right out of the gene pool moreover this is not just a natural logical prediction but it's a testable prediction.

00:37:48.700 Darwin lived a long time ago right then we can look what has happened since then when we've used technology to probe things beyond what we could experience with our senses.

00:37:58.700 So the prediction is that whenever we with technology study physics that was inaccessible to ancestors. It should seem weird so let's look at the fact sheet at the score card we started what happened when things go much faster than our ancestors near the speed of light.

00:38:15.700 Time slowed down. So weird that Einstein never even got the Nobel Prize for it because my Swedish commercially countrymen on the global committee thought it was too weird. You look at what happens when things are really really huge and you get black holes which were considered so weird again.

00:38:31.700 The long time until people really started to accept them and then you look at what happens when you make things really small.

00:38:44.700 Everything that's new is weird by definition. You can talk about people struggling to understand why certain historical events happen.

00:38:54.700 We could talk about how not intuitive certain kinds of music are. This thing about well it's evolutionarily costly to have a brain that can understand the secrets of the universe.

00:39:05.700 It misunderstands that that brain is only able to detect the tiger sneaking up on them just sneaking up on the proverbial cave woman he just talked about in order to understand that that's happening.

00:39:25.700 The remarkable thing is that the same mind using the same process can both detect the tiger or detect the false positive of the tiger and also look up into the sky at those pinpricks of light and also figure out they're actually super hot furnaces of nuclear fusion.

00:39:41.700 It's the same process going on of guessing and checking against reality. That's what's going on. And this is why the brain was selected for the human mind was selected for.

00:39:58.700 But the fundamental way in which we come to an understanding of reality and understand what a tiger is and what that noise might be at night is a different kind of a thing to what any other animal does.

00:40:14.700 Any other animal is not going to learn quite so well over time that the noise it just heard at night is not a reason to run off as fast as it possibly can. But we can learn that false positives are a thing.

00:40:28.700 But what we thought was a tiger. In fact, that's that same bush blowing in the wind and making that noise that kind of sounds like a tiger creeping up on us. But a gazelle or a wielder beast or whatever tigers go after. They don't have that same capacity. They're always going to run.

00:40:44.700 They're instinct. They have no choice but to obey their instincts. We're different. We can routinely violate what our instincts are telling us to do because we're also interpreting those interpreting those instincts in a way that animals just aren't.

00:41:00.700 But we explain what that sense data was. We explained to ourselves to our unsatisfaction. Now we also have the system where, yeah, sure, we can react immediately to something. And that's good too. So we have at least two systems. The animal, the other animals only have this one.

00:41:15.700 We can only do what their instincts tell them to do. We can go well beyond our instincts. Is it evolutionarily costly? Yes, but it also appears to have been the most evolutionarily valuable powerful thing that is ever evolved. And as we like to say, it's a prelude to the rest of evolution that's going to happen, which is going to be mimetic. We are the general intelligence. We are the super intelligence. That's what we are.

00:41:41.700 We have this universal mind that can literally understand and explain anything, anything. So far so good, by the way, this is known argument from induction. It's just saying that the only known explanation for the fact that we can continually make progress and have always made progress and haven't reached a stumbling block yet.

00:42:03.700 We've always got open questions, but they're not walls before us, not walls before our progress. The only known explanation for that is we have a universal mind, a universal mind that can understand anything.

00:42:14.700 And if it wasn't universal, shouldn't we have known by now, but people keep on saying, you know, scientists especially who don't know the philosophy, keep on saying, well, just you wait kind of thing.

00:42:24.700 Just you wait, we're going to get the problem that we can't possibly solve. There's going to come the gap in our knowledge of physics, which cannot be filled, no matter how hard we try, because our brain will be incapable of it.

00:42:36.700 And people have always been saying this, since religious times, it's like there's no point trying to understand the world, just read the book.

00:42:43.700 And you only God can understand the world. This was the prevailing view. This was why theologians and others and priests were saying to the scientists early on in the philosophers, they're actually committing sacrilege by even trying to do this stuff.

00:42:57.700 You should bow down to the authority of the books and of the priests, because we know the truth. Your puny mind can't possibly understand the laws of nature, the laws of motion, don't be ridiculous.

00:43:10.700 And so have we moved beyond that sort of ideology? No, we haven't. But it's just now scientists often making that claim rather than the priests.

00:43:19.700 Rather than the priests saying, don't try and understand reality because only God understands reality. It's now the scientists turning around and saying, well, maybe they'll write all along.

00:43:28.700 Maybe we can't understand reality. Maybe we have to look to the aliens, the gods, in order to get a full understanding of reality.

00:43:37.700 Because our puny human minds can't even begin to scratch the surface. We've got Newtonian mechanics. We're very lucky to have moved beyond that into general relativity and into quantum theory.

00:43:47.700 But maybe string theory will bring those two things together. But you've got to expect the enders coming. The enders knife or understanding. Either we complete physics or we're going to encounter the problem we can't solve.

00:43:58.700 That's what we should expect. Of course, the David Deutsch worldview tells us, no, we should expect exactly the opposite.

00:44:04.700 We should expect to continually solve our problems. And in retrospect, we look back and go, oh, look, those other theories are actually easy and intuitive.

00:44:13.700 When you've got the right way to think about them, they're actually intuitive after all. Okay, let's keep on going.

00:44:19.700 Then you look at what happens when you make things really small, so small that our ancestors couldn't see them. And you find that elementary particles can be in several places at once, extremely counterintuitive, the point that people are still arguing about what it means exactly, even though they can see the particles really can do this weird stuff.

00:44:40.700 And the list goes on, whenever you take any parameter out of the range of what our ancestors experienced, really weird things happen.

00:44:49.700 If you have very high energies, for example, like when you smash two particles together near the speed of light that the Lord had wrong collider at CERN,

00:44:57.700 you know, if you collide a proton and an anti proton together and out pops a Higgs boson, you know, that's about as intuitive as if you collide a Volkswagen with an Audi and out comes a cruise ship.

00:45:10.700 And yet this is the way the world works. So I think the verdict is in whatever the nature of reality actually is.

00:45:18.700 This seemed really weird to us. And if we therefore dismiss physics theories just because they seem counterintuitive, we're almost certainly going to dismiss whatever the correct theory is once someone actually tells us about it.

00:45:32.700 So again, I agree with him. I agree with that sentiment that we should expect our new theories to be counterintuitive in the same way that anything new is going to be counterintuitive.

00:45:51.700 You know, the next iPhone, people kind of get annoyed when they change the operating system too much. It's like, it's no longer intuitive. It was. Now, why was it intuitive that the first iPhones weren't intuitive?

00:46:02.700 Well, some people said they were, but it took, there's a learning curve. Any new bit of software people complain, you know, it's not intuitive. And then after a little bit of use, oh, this is great. It's intuitive.

00:46:13.700 What does it take to go from not intuitive to intuitive? Well, learning, conjuring, guessing what things are true and by your own lights coming to understand stuff.

00:46:24.700 That's all this use of the word intuitive means. It just means understanding. Can you understand it? And then it becomes intuitive like mathematicians famously, all the time,

00:46:36.700 intuiting their way to stuff that people who don't understand mathematics to that level of proficiency. So don't find intuitive. It takes a while to develop intuitions, intuitions about stuff.

00:46:48.700 A professional gymnast is going to find certain movements of the body intuitive that the rest of us don't. A great pianist is going to understand how to play certain pieces intuitively that the rest of us don't.

00:47:01.700 This is eventually find certain things intuitive. But at first they're jarring. At first the new laws of the universe when they're explained to you, are not going to seem intuitive.

00:47:12.700 Until they are, once you've understood them. Now, they still might seem surprising in retrospect, but only because you remember your old self.

00:47:19.700 Your old self remembers what it was like not to understand the phenomena of dark energy or the Heisenberg uncertainty principle or the relativity of time.

00:47:30.700 Your old self. But once you learn these things, once you get what's going on intuitive, it just means understanding. But you can still remember what it was like not to understand those things.

00:47:46.700 But only in light of the previous theory, the previous understanding of reality, the false misconceptions that you had.

00:47:54.700 So yes, I totally agree. I totally agree that the next theories that we're going to develop, not just in physics, but physics is kind of preeminent in this sense of really challenging our intuitions.

00:48:07.700 But everywhere. I would expect that everywhere. The reason why we have these open questions whether they're being biology, geology, astronomy, anywhere is because nothing is intuitive in that way.

00:48:18.700 If it was, we'd just be intuitive away, easily guessing, easily understanding the open question, the solutions to the open questions. But the reason we don't, not intuitive.

00:48:28.700 Nothing is. What is intuitive? I don't know. I would just say that this word is being used as synonymous with stuff you already know, intuitive is stuff you already know.

00:48:40.700 And so new stuff, if it kind of challenges what you already know, refutes what you already know, then yeah, it's jarring and it can be difficult.

00:48:49.700 Sometimes you've got to fit it into your worldview in some way, but once you do, then it all becomes intuitive again.

00:49:01.700 So I'm wondering though, whether this slippery slope is in fact more slippery than we're admitting here though, because how do we resist the slide into total epistemological skepticism?

00:49:15.700 So for instance, why trust our mathematical intuitions or the mathematical concepts born of them, or the picture of reality in physics that's arrived at through this kind of bootstrapping of our intuitions into areas that are counterintuitive?

00:49:32.700 Because I understand why we should trust these things pragmatically. It seems to work, we can build machines that work, you know, we can fly on airplanes.

00:49:40.700 There's a difference between an airplane that flies and one that doesn't, but as a matter of epistemology, why should we trust the picture of reality that math allows us to bring into view?

00:49:51.700 Again, we are just apes who have used the cognitive capacities that have evolved without any constraints that they accord with reality at large, and mathematics is clearly, insofar as we apprehend it, discover it, invent it, and extension of those very humble capacities.

00:50:18.700 If it's the wrong question, epistemologically, he's asking, why should we trust any of these theories given the counterintuitive nature and the subtleness of mathematics that we don't seem to have really got to evolve brainful?

00:50:34.700 Emology is not about trust, it's about knowledge, and we don't need to trust our knowledge, because, as I've been saying on recent episodes of talkcast, generally speaking, you've only got the one explanation, the insights, it's just the explanation.

00:50:47.700 And so, what else can you rely upon in order to solve your problems, and that, in the Perperian framework, is why, in answer to Sam's question, why it is that we should not trust these theories, but accept these theories as explanations of reality.

00:51:08.700 Because they solve the problem, they solve whatever the problem happens to be that we have, we have problems, we come up with solutions, and in science we're able to test to see if those solutions really work, and if they do, then we say, hey, this explanation, this solution, it's got something right, it's saying something true about reality.

00:51:30.700 It's solving our problem, it's making predictions into fields, we never could have guessed, it's postulating the existence of entities that we never imagined, but we can test for the reality of.

00:51:54.700 Trust isn't required, in fact, we should expect them to be overturned at some point, so we shouldn't be trusting them in the sense of thinking they're true for no good reason.

00:52:03.700 Trust is a word that's kind of like faith, why should we have faith in this theory? Why should we trust in this theory?

00:52:24.700 Well, because it's got something right, here you go, test the thing, test this logical outcome called a prediction of the theory, and you'll see that it works,

00:52:38.700 What else could it mean other than it's making a prediction about the nature of reality, and it's getting it right, where no other theory, no other competing theory is?

00:52:47.700 So it's got something right, it was able to tell you what's going to happen, and it's only able to do that, because it's making all of these other claims about reality simultaneously.

00:52:56.700 This grand theory is making a bunch of multitudinous number of claims that fall under the umbrella of the explanation, we've picked out one and gone, it works there.

00:53:06.700 In fact, it works universally, anytime you ask anything of it within its domain of applicability, it works.

00:53:13.700 So it is capturing reality to some extent, not perfectly, not finally, that will never happen, but it's got something right, and that's just synonymous with, it's saying something true.

00:53:25.700 That's all. So that's the way I like to explain. Why it is we regard explanations that we hold as scientific theories of the world as being truly good explanations of reality, and not merely useful fictions, not merely useful fictions.

00:53:42.700 They really do capture something. Now, we can't say finally of any of them. Well, this is the bit here that is certainly once and for all finally true.

00:53:49.700 No, in fact, it could be that the truth is in explicit content that we can't quite say, but it preserved from one theory through to another theory through to another theory as we make progress and improve towards a better and better understanding of objectively true reality of the reality that's out there that has been captured by our best explanations.

00:54:17.700 Some people tell me sometimes that theories that physicists discuss at conferences from black holes, the parallel universe is sound even crazier than a lot of myths from all time about fire, flame throwing dragons and whatnot.

00:54:32.700 So to me, there is a huge difference here in that these physics theories, even though they sound crazy, as you yourself said here, they actually make predictions that we can actually test.

00:54:42.700 And that is really the crux of it. If you take a theory quantum mechanics seriously, for example, and assume that particles can be several places once, then you predict that you should be able to build this thing called a transistor, which you can combine and vast numbers and build this thing called a cell phone, and it actually works.

00:55:00.700 This is very linked, I think, to where we should draw the borderline between science, what's science and what's not science.

00:55:07.700 Some people think that the line should go between that which seems intuitive and not crazy and that which feels too crazy.

00:55:15.700 And I'm arguing against that because black holes seem very crazy at the time and now we've found loads of them in the sky.

00:55:22.700 To me, instead, really that the line and the sound that divides science from what's not science is, the way I think about it is, what makes me a scientist is that I would much rather have questions I can't answer than have answers I can't question.

00:55:36.700 One thing you're emphasizing here is that it's not in the strangeness or seeming acceptability of the conclusion, it's in the methodology by which you arrived at that conclusion and falsifiability and testable predictions is part of that.

00:55:55.700 I don't think you would say that a proparian conception of science as a set of falsifiable claims subsumes all of science because they're clearly scientifically coherent things we could say about the nature of reality where we know there's an answer there, we just know that no one has the answer.

00:56:13.700 The very prosaic example I often use here is how many birds are in flight over the surface of the earth at this moment.

00:56:19.700 We don't know, we know we're never going to know because it's just changed before I can get to the end of the sentence.

00:56:26.700 But it's a totally coherent question to ask and we know that it just has an integer answer leaving spooky quantum mechanics or parallel universes aside.

00:56:36.700 If we're just talking about earth and birds as objects, we can't get the data but we know in some basic sense that this reality that extends beyond our perception guarantees that the data in principle exists.

00:56:49.700 I think you say at some point in your book that a theory doesn't have to be testable across the board, it just parts of it have to be testable to give us some level of credence in its overall picture. Is that how you view it?

00:57:22.700 This notion, this misconception about Popperian epistemology is near ubiquitous among anyone who's not a self-described popularian of a sort.

00:57:39.700 He talked about a line of demarcation between science and non-science, which is drawn by this testability criterion, but he wasn't saying that you need to be able to

00:57:52.700 It's an in principle idea. In principle, Sam's thought experiment of how many birds are in flight right now is indeed in principle testable.

00:58:00.700 Because as he said, there's an answer. You can imagine some series of lasers or something or other that could actually count up, you know, or satellites or something like that.

00:58:10.700 That could, in principle, gather that data. It could in principle be gathered. There's data there to be gathered, which is what makes it a scientific claim, if you like.

00:58:35.700 Now, what this number of birds in flight is all about, I don't know, but it's one of those things where we say it's a philosopher talking purely in the abstract.

00:58:44.700 And not actually solving a problem. Once you stick to asking the question, what problem are you trying to solve?

00:59:00.700 All these don't kind of things. They're useful biological problems. Now, number of birds in flight, I don't know what problem that would possibly solve.

00:59:20.700 There's all these different kinds of explanations from moral through the political, historical, mathematical, philosophical, scientific ones as well.

00:59:36.700 No, in fact, the Popperian view, as well, David Deutscher's explanation of the Popperian view, says very much that what we're doing is explaining the scene, the stuff we can observe, in terms of the unseen, the stuff that, in principle, we can't observe.

00:59:50.700 But we know as there, because we can test the theory via some other means. My go to example here is, of course, we know what's going on in the core of the Sun.

1:00:00.700 We know, we have good explanations that what's going on there is something like the PP chain in order to produce helium.

1:00:11.700 This fusion reaction is happening there, but no one's ever going to go to the core of the Sun and gather the relevant data there.

1:00:17.700 Instead, what we do is we interpret the light coming from the Sun, all the way here on Earth and satellites that are around the Sun, and looking at spectra, and inferring on that base is explaining what must be going on in the core.

1:00:31.700 Even though we can't observe what's going on there, that's Popperian. That's Popperian. There is no rival to that theory, by the way. No rival whatsoever.

1:00:40.700 We can rule out anyone who comes along with the rival by doing crucial tests, because in theory, their theory would make predictions.

1:00:48.700 It would make specific predictions that are different to the theory that we have about stellar nucleosynthesis, stellar fusion, how this wider Sun shines, and what must be going on in the core of the Sun.

1:01:02.700 Now, this is where Popper has been invoked, and Max is about to say he's sympathetic to Popper, but let's just hear what he says.

1:01:11.700 I'm actually pretty sympathetic to Popper, and the idea of testability works fine for even these crazy concepts, sounding concepts like parallel universes and black holes, as long as we remember that what we test are theories, specific mathematical theories that we can write down.

1:01:32.700 But parallel universes are not a theory. They're a prediction from certain theories. The black hole isn't a theory either. It's a prediction from Einstein's general relativity theory.

1:01:42.700 Once you have a theory in physics, it's testable as long as it predicts at least one thing that you can go check.

1:01:49.700 You can falsify it if you check that thing and it's wrong, whereas it might also make just because it happens to also make some other predictions for things you can never test. That doesn't make it non-scientific as long as there's still something you can test.

1:02:02.700 For example, the theory of general relativity predicts exactly what would happen to you. If you fall into the monster black hole in the middle of a galaxy that weighs four million times much as a Sun, it predicts exactly how you're going to win. You're going to get spaghettified and how you're going to get spaghettified and so on, except you can never actually do that experiment and then write an article about it.

1:02:26.700 The multiverse is in a theory. It's a prediction. Black holes aren't a theory. They're a prediction. Well, again, in the Papirian framework, these things are it's all theoretical. It's all conjectures. It's all interpretations of stuff.

1:02:41.700 I might want to say, well, there is this broader theory called general relativity, which generates certain predictions, some of which are black holes. But the black hole itself is a theory of certain objects that actually exist out there.

1:02:56.700 It can themselves be tested for. So that part of general relativity can be tested for. If general relativity makes a prediction of black holes and we never detect black holes, that's not a refutation of general relativity. Is it? It could or could not be a problem. Of course, postulating the existence of something you never find in it doesn't mean that thing doesn't exist.

1:03:16.700 But let's say black holes didn't exist and general relativity was the only theory we had. Well, it's still only got general relativity and it would kept still capture something true about reality. It might not get everything true, but we should expect that anyway.

1:03:29.700 Now, I'm not saying all of this in order to defend Papirian epistemology, to sort of stand here and say, no, Carl Popper got it all right. And if only people would listen to David Dijkstra, kind of saying that it's important. It's useful if people understand epistemology better because they're then they're thinking on certain matters is clearer, more refined. It just makes sense. It cohears together.

1:03:53.700 And all the stuff they're saying that I agree with, it's just remarkable that they kind of distancing themselves. Well, Sam is kind of distancing himself in some way, seemingly from Popper.

1:04:06.700 And he's done this on various podcasts, of course, over the years. But often when he thinks he's disagreeing with Popper, he's not. He's disagreeing with a version of Popper that never actually existed.

1:04:17.700 Well, that maybe he read in a book somewhere by someone who disagreed with Popper. See, I see this very often. I see this very often.

1:04:25.700 But Max is totally right in saying, there are these things that can't be observed out there. And that's fine. That's fine.

1:04:32.700 As I just said about the core of the Sun, as I've said before about the moment of the Big Bang, we know it happened, but no one's going to be there.

1:04:40.700 And the David Deutsch says, dinosaurs, dinosaurs are literally unobserved unless we invent time machines. No one's ever going to observe a dinosaur, or maybe genetic engineering of the future.

1:04:50.700 But all we have right now are fossils, rocks. That's all we have. We don't have access directly to dinosaurs. We can't observe the very thing, the unseen thing, the dinosaur that explains what we do see the fossil.

1:05:05.700 This is perfectly popularion, perfectly popularion. And I would argue it's only popularion epistemology that properly accounts for this that says you have an explanation of the unobserved stuff,

1:05:19.700 a Bayesian epistemology, and these other epistemologies talk about, well, it all comes down to observation if you can't observe the thing that somehow rather it's ruled out as being non-scientific because I have this empiricist bent, not all versions, I accept that. But also there's this focus on prediction, prediction as well.

1:05:37.700 Whereas we say, and I think Max could have subtly kind of got things wrong there a bit where he was saying that we could falsify general relativity, let's say something was pretty good about black holes or something.

1:05:50.700 Only if we have an alternative, the function of evidence, the function of observation in science at that level is to distinguish between competing theories.

1:05:58.700 And if you have no competitor to general relativity, which is explaining all of your phenomena, maybe except for one thing that it gets wrong that just systematically gets wrong all the time, for whatever reason.

1:06:09.700 Well, you've got nowhere else to leap to until such time as someone comes along and is able to explain that thing and everything else that general relativity can explain.

1:06:17.700 In general relativity, we had problems with gravity, we couldn't predict exactly why Mercury's orbit was, couldn't explain why Mercury's orbit was doing what it was doing.

1:06:28.700 Now, for the time between when we only had Newton's theory and when we had these anomalies with Mercury's orbit and when we got general relativity between that time, when we got general relativity, there was nothing else to do, there was nothing else for it but to rely on Newton's theory of gravity.

1:06:46.700 At that time, when we've got these problems with Mercury's orbit, we literally didn't know them, people were postulating things like another planet perturbing, altering the orbit of Mercury as it went around the Sun.

1:07:00.700 They didn't know, was it the theory of gravity that was wrong in some way or was it the observations being made that were wrong in some way, was there a hidden planet causing this strange orbital properties of Mercury as it went around the Sun?

1:07:21.700 We don't know if it's the theory that's wrong, we don't know if it's our observation strong, we don't know if there's some underlying hidden thing yet to be observed that will explain that I find the solution to the problem that we have.

1:07:32.700 So I think we'll call this part one, so this will be enough for today, but I'm going to come back to this discussion, it's a fascinating discussion, you can see that I am being very nitpicky,

1:07:42.700 but I think it's a helpful insight and in-road into distinguishing these kind of differences between, one would presume, rationally minded people, scientifically literate types, and people who have more or less an all-encompassing worldview, and people who might have cobbled together for lots of these that are kind of separate and may not cohere in some ways, I don't know how to put that, but until next time, bye bye.

Things that make you go mmmm? Part 1 - Metaphysics and Misconceptions