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Why does physics even work? · Daniel and Kelly’s Extraordinary Universe

0:08
Speaker 1: Science seems to work. We can argue about the philosophical
0:13
Speaker 1: foundations of it, and whether a photon is a particle
0:16
Speaker 1: or a wave. We can wonder whether the universe that
0:19
Speaker 1: we perceive out there is real or is just an
0:22
Speaker 1: elaborate hoax like in the matrix, and how we might
0:26
Speaker 1: ever know the difference. But in the end, what is
0:30
Speaker 1: beyond question is that science does work. We can build
0:34
Speaker 1: airplanes that almost never crash. We can build incredible miniature
0:39
Speaker 1: devices that rely on the quantum properties of electrons. We
0:43
Speaker 1: can and have sent robots to crawl over the surface
0:47
Speaker 1: of other planets and send us back pictures. All of
0:51
Speaker 1: this stuff works because of science. Science lets us build
0:55
Speaker 1: and test and refine little mathematical stories about how things work,
0:59
Speaker 1: and then calm definitely use those mathematical principles in totally
1:03
Speaker 1: different contexts. Ideas that we have in the shower, then
1:06
Speaker 1: test in basement labs. They all work inside your iPhone
1:10
Speaker 1: and on the space station. We can confidently use what
1:14
Speaker 1: we have learned, even if we aren't exactly sure why
1:19
Speaker 1: science works and whether the universe out there is actually real. Hi,
1:40
Speaker 1: I'm Daniel. I'm a particle physicist and a professor at
1:43
Speaker 1: UC Irvine, and I want to know what's real about
1:47
Speaker 1: the universe. I don't want to just have ideas that work.
1:50
Speaker 1: I want to know the truth about the universe. And
1:54
Speaker 1: welcome the podcast Daniel and Jorge Explain the Universe, where
1:58
Speaker 1: our goal is to do just that, to explore with
2:01
Speaker 1: you what we do and don't know about the universe,
2:05
Speaker 1: how microscopic little particles interact at the smallest levels, and
2:08
Speaker 1: how all of their twoing and frowing and buzzing weaves
2:12
Speaker 1: itself together into the world that we know with very
2:15
Speaker 1: different rules, which is just a small part of the
2:18
Speaker 1: larger context of stars and galaxies and superclusters slashing around
2:23
Speaker 1: in a web of dark matter to make this glorious
2:25
Speaker 1: and crazy universe. My co host and a friend, Jorge,
2:29
Speaker 1: is on vacation this week, so I'm taking the opportunity
2:32
Speaker 1: to take a bit of a digression into the philosophy
2:35
Speaker 1: of science, together with an exciting guest. Now, what's amazing
2:39
Speaker 1: to me about science is that we are capable at
2:42
Speaker 1: all of understanding the universe that jumped up apes with
2:46
Speaker 1: tiny little brains on a little rock in an irrelevant
2:49
Speaker 1: galaxy can just by doing a few experiments and writing
2:53
Speaker 1: down some math symbols build a mental model of how
2:57
Speaker 1: the universe works, and a model that seems to work
3:01
Speaker 1: pretty well. This model has revealed how stars form, and
3:04
Speaker 1: how the universe expands, and how electrons funnel through weird metals,
3:09
Speaker 1: and how the whole universe is filled with an invisible
3:12
Speaker 1: Higgs field that gives matter to microscopic particles. It's incredible
3:16
Speaker 1: what we have learned about the nature of the universe.
3:19
Speaker 1: The very fact that you are hearing this podcast right
3:22
Speaker 1: now relies deeply on our understanding of the basic rules
3:26
Speaker 1: of the universe and our ability to manipulate and rely
3:29
Speaker 1: on them. But why is that possible? Why does it
3:34
Speaker 1: even work? Because what I said a moment ago was
3:37
Speaker 1: a bit of a stretch of the truth. For all
3:39
Speaker 1: of the successes of particle physics, we don't actually have
3:43
Speaker 1: an understanding of the basic rules of the universe. We
3:47
Speaker 1: don't know what the basic bits of the universe are
3:50
Speaker 1: and what their rules are. Are they strings? Is it
3:54
Speaker 1: a quantum foam? Is it something completely different than we
3:57
Speaker 1: haven't yet or maybe could never even imagine or grapple with.
4:01
Speaker 1: What we do have is a set of rules that
4:03
Speaker 1: work for the experiments that we can do, but we're
4:06
Speaker 1: pretty sure it's not the final answer, not that they're
4:10
Speaker 1: wrong and it's all a hoax, but that it will
4:12
Speaker 1: be eventually replaced by a deeper understanding. The way Newton's
4:17
Speaker 1: physics worked for the experiments that could be done in
4:19
Speaker 1: his day, but we're later replaced by Einstein's more general theory.
4:24
Speaker 1: The way you can use F equals m A to
4:27
Speaker 1: calculate how a ball flies through the air, and it
4:30
Speaker 1: certainly works even if you don't understand the quantum frothing
4:33
Speaker 1: happening inside of it. What we have in particle physics
4:36
Speaker 1: is the same thing. We don't think it's fundamental. We
4:40
Speaker 1: don't think it describes the basic bits of the universe.
4:43
Speaker 1: We think it's effective, meaning that it works, but it
4:46
Speaker 1: describes things that emerge from the fundamental pieces. But it
4:51
Speaker 1: still works even though we don't know what the basic
4:54
Speaker 1: pieces are and the rules that they obey. We have
4:57
Speaker 1: found the non basic pieces and the rules that those
5:00
Speaker 1: non basic pieces obey. For example, we have rules of
5:04
Speaker 1: economics and they mostly work. But people and money are
5:08
Speaker 1: not fundamental elements of the universe. You can have a
5:11
Speaker 1: universe without people and money, and most of the history
5:14
Speaker 1: of the universe didn't have people or money. But once
5:18
Speaker 1: people and money emerge, you don't have to describe the
5:21
Speaker 1: economy of a country using particle physics or string theory.
5:26
Speaker 1: You can find basic mathematical laws that describe economics and
5:30
Speaker 1: are pretty simple, just like F equals I may is
5:33
Speaker 1: pretty simple, but it ignores all of the quantum details underneath.
5:38
Speaker 1: So why does that work? Why is it possible? And
5:41
Speaker 1: what does it mean about whether what we have learned
5:45
Speaker 1: is true and fundamental to the universe, a real description
5:49
Speaker 1: of what's out there, or if it's just a set
5:51
Speaker 1: of mathematical stories that humans tell ourselves that happen to
5:55
Speaker 1: work very well. So today on the podcast, we'll be
5:58
Speaker 1: asking the question why does physics even work? Why is
6:07
Speaker 1: it possible to tell mathematical stories about the universe out
6:11
Speaker 1: there without knowing the deepest underlying truth. We know it's
6:15
Speaker 1: possible to make chicken soup and iPhones without knowing quantum gravity,
6:19
Speaker 1: but why can we Does that mean that the stories
6:22
Speaker 1: we are telling, the physics ideas we have developed are
6:25
Speaker 1: not real in some deep, true sense. Would alien scientists
6:29
Speaker 1: come up with the same theories or have a different
6:31
Speaker 1: concept of how to describe the universe. To help us
6:34
Speaker 1: probe these questions, I've invited an expert in this area,
6:37
Speaker 1: Professor Tim O'Connor. Tim is a professor of philosophy and
6:41
Speaker 1: cognitive science at Indiana University, where he specializes in these
6:45
Speaker 1: types of questions and especially the phenomenon of emergence cases
6:49
Speaker 1: where it's possible to describe things at a higher level
6:52
Speaker 1: without knowing the underlying pieces. So it's my pleasure to
7:05
Speaker 1: introduce to the podcast Professor Tim O'Connor Tim. Thank you
7:09
Speaker 1: very much for joining us today. Glad to be with you, Daniel.
7:12
Speaker 1: As well as being an expert on philosophy of science
7:14
Speaker 1: and emergence, I see that you also claimed the title
7:16
Speaker 1: of Philo Pong World Grand Champion or the world's leading
7:20
Speaker 1: table tennis player among properly credential philosophers. Tell us about
7:24
Speaker 1: how you figure that out? How you determined that you
7:26
Speaker 1: could claim that title. Oh, I declared the title, and
7:34
Speaker 1: the interesting thing is that no philosophers have disputed that
7:38
Speaker 1: I hold the title, and I think the reason is
7:40
Speaker 1: that those who like to play serious table tennis figured
7:45
Speaker 1: out that. Great. Then all I have to do is
7:46
Speaker 1: beat you, and then I get to claim the title.
7:49
Speaker 1: So I have defended the title on a few occasions. Um,
7:52
Speaker 1: but I expect to be losing the title the next
7:55
Speaker 1: time I go back to China. Well, I think it
7:57
Speaker 1: made me says something about philosophy that you can just do,
8:00
Speaker 1: say yourself champion, and then you know, see, if it
8:02
Speaker 1: stands up to scrutiny, that's it. It's kind of like
8:04
Speaker 1: a homesteading thing. If no one disputes it, then at
8:07
Speaker 1: a certain point that's I own it exactly. So, when
8:10
Speaker 1: you're not winning ping pong matches, you're a philosopher of science,
8:14
Speaker 1: tell us about that. What got you into philosophy of science?
8:16
Speaker 1: What are the most important questions in your mind that
8:19
Speaker 1: we should be asking about our universe? Great? Uh so, well,
8:23
Speaker 1: I start out and still think of myself fundamentally as
8:27
Speaker 1: a metaphysician, where metaphysics asks the really most general foundational
8:33
Speaker 1: questions about reality, about fundamental categories like object, property, space, time.
8:40
Speaker 1: Does the physics wholly determine what one should think about
8:44
Speaker 1: space and time? It certainly constraints, um, what one should say,
8:48
Speaker 1: and I'm more in the latter campic constraints, but doesn't
8:50
Speaker 1: wholly determine how we think about it. But the relationship
8:53
Speaker 1: of philosophy metaphysics to science is a challenging question in
8:58
Speaker 1: its own right. And of course the two subjects originally
9:02
Speaker 1: refused in the history of Western thought, going all the
9:05
Speaker 1: way back to thinkers like Aristotle. But well on up
9:08
Speaker 1: to the time of Newton. Um you had a one
9:12
Speaker 1: job title natural philosopher, which was a description of science
9:16
Speaker 1: as we think of it, as those philosophical questions that
9:19
Speaker 1: concerned the natural world. And I think it's beginning with Newton,
9:23
Speaker 1: who famously, when pressed for an account or an explanation
9:28
Speaker 1: of how his theory of gravitational attraction action at a distance,
9:33
Speaker 1: how we could conceive it seemed inconceivable, how we could
9:36
Speaker 1: make sense of that, he famously said about you know,
9:38
Speaker 1: about that, I feigned no hypotheses. And he's beginning to
9:42
Speaker 1: show a certain sort of well, you know, you might
9:45
Speaker 1: ask a certain kind of philosophical question, but as far
9:48
Speaker 1: as doing science, which is what fundamentally Newton was up to, Uh,
9:53
Speaker 1: the theory works beautifully, the mathematics works, it's predictively successful,
9:58
Speaker 1: and so he was willing to go with that. So
10:00
Speaker 1: I want to talk to you specifically in a bit
10:02
Speaker 1: about emergence and how the world that surrounds us arises
10:05
Speaker 1: and how we make sense of it. At first, I
10:06
Speaker 1: want to start with a bigger picture of why we
10:08
Speaker 1: ask these questions. As you say, we see that science works,
10:11
Speaker 1: We know that it does. It's the reason that we're
10:13
Speaker 1: talking right now. So if Newton doesn't care about questions
10:16
Speaker 1: like why does it work? Or you know, is the
10:19
Speaker 1: universe out there real or is it just a story
10:21
Speaker 1: in our minds, why do we care about those questions?
10:24
Speaker 1: Why are those questions important to figure out? Because ultimately,
10:27
Speaker 1: I think we were driven to wanting to have a
10:30
Speaker 1: consumption of reality on which it's explicable. Uh it makes sense.
10:36
Speaker 1: I mean explicable, not in the sense necessarily if involving
10:39
Speaker 1: purpose or anything like that, but just rationally explicable. And
10:43
Speaker 1: so simply retreating to um an instrumentalist few syite of science,
10:50
Speaker 1: UM saying it's science just delivers sophisticated instruments that enable
10:56
Speaker 1: you to predict future observations and ultimate control future patterns
11:01
Speaker 1: to degree through technology. That sort of conception leaves open
11:06
Speaker 1: you know why, but why does it work? It can
11:08
Speaker 1: seem like a cosmic coincidence um, that reality exhibits deep patterns.
11:14
Speaker 1: If all you're willing to say is there are these
11:17
Speaker 1: deep patterns and there's no rational intelligibility behind them. So
11:21
Speaker 1: not everyone shares it, but it's the fundamental philosophical impetus
11:26
Speaker 1: I guess to want to understand why things are as
11:30
Speaker 1: they are. Um, And so depending on one's conception of science,
11:35
Speaker 1: science may or may not even give you that right.
11:38
Speaker 1: So so there are famous scientists too who insisted that
11:43
Speaker 1: in a sense, science doesn't yield explanation. I mean, Richard
11:46
Speaker 1: Feyneman did make noises along those lines. Famous twentieth century
11:50
Speaker 1: physicists never been others. He said, uh yeah, he's got
11:55
Speaker 1: a great quote somewhere. He says, you know, you want
11:57
Speaker 1: to understand, you know, what reality is like, go ask
12:00
Speaker 1: a philosopher dripping with this. You're saying, physics doesn't give
12:05
Speaker 1: you that. Physics gives you these sophisticate instruments or devices
12:10
Speaker 1: in the form of theories, powerful mathematics, mathematized theories that
12:14
Speaker 1: are predictively successful, and that's it. But most scientists, in
12:18
Speaker 1: my experience, they are you know, scientific realists. They think
12:21
Speaker 1: that the things that we're probing are really out there.
12:24
Speaker 1: I mean, the reason that I'm a particle physicist and
12:26
Speaker 1: not a mathematician is that I want to know what's
12:29
Speaker 1: really out there. I think of myself was revealing the truth.
12:32
Speaker 1: And when I'm at cern if I ask people, hey,
12:35
Speaker 1: do you think the Higgs boson that we discovered is real?
12:38
Speaker 1: Or is it just something in our models that let's
12:40
Speaker 1: accurately predict experiments, most of them would look at me
12:43
Speaker 1: like I'm crazy, you know, like I had something bad
12:45
Speaker 1: for lunch. It feels to me like they're doing philosophy
12:48
Speaker 1: by rejecting the question, even though they don't imagine they're
12:52
Speaker 1: doing philosophy. Why do you think that's sort of the
12:54
Speaker 1: natural position of most physicists to imagine, you know, a
12:58
Speaker 1: strong philosophical argument and um that everything we're out there
13:02
Speaker 1: is actually real. Why do you think that most physicists
13:04
Speaker 1: don't consider the whole spectrum of philosophical positions there? I
13:08
Speaker 1: think because it's a sort of natural or default human inclination.
13:13
Speaker 1: First of all, to be a metaphysical realist in the
13:16
Speaker 1: in the minimal sense of there is a way the
13:19
Speaker 1: world is subjectively speaking, and then to go beyond that,
13:23
Speaker 1: to think if we have powerfully predictively accurate ways of
13:30
Speaker 1: describing the patterns of our experiences. Then those must correspond
13:36
Speaker 1: to something objective. If I'm being very vague here, but
13:40
Speaker 1: something in reality is accounting for the fact that our
13:44
Speaker 1: inductions are successful. It may not be a perfect isomorphic
13:49
Speaker 1: overlap right between what we say, either in common sense
13:53
Speaker 1: predictions or categorizations, or even in high level theory, but
13:58
Speaker 1: there's some degree of congruents um there. We're tracking. I
14:03
Speaker 1: guess with what I'm trying to say, we must be
14:05
Speaker 1: tracking something real. And then when you think about fundamental physics,
14:09
Speaker 1: because it's going so deep into the foundations, the inclination,
14:14
Speaker 1: I guess it becomes natural to think we're getting closer
14:17
Speaker 1: and closer to it isomorphism. The categories we're using are
14:22
Speaker 1: are are tracking very directly these entities. But it feels
14:27
Speaker 1: something more squishy than we usually find in physics. You know, physics,
14:31
Speaker 1: we have math and calculations and these sorts of things.
14:34
Speaker 1: Here we're talking about like a feeling that what we're
14:37
Speaker 1: seeing out there is real, and you know, our ideas
14:40
Speaker 1: about the universe must be real. It feels a little
14:43
Speaker 1: bit more susceptible to you know, cultural bias or parochialism,
14:48
Speaker 1: or thinking the way people have always thought. To me,
14:50
Speaker 1: one way to make sense of this question, to make
14:52
Speaker 1: it a bit more concrete, is imagine a scenario like
14:55
Speaker 1: we meet alien physicists and we talk to them about
14:59
Speaker 1: the universe. If what we're learning about the universe is
15:02
Speaker 1: real in a sense that it's not just biased by
15:04
Speaker 1: our human conception, then we can imagine maybe they have
15:07
Speaker 1: discovered the same things. They also found the Higgs boson,
15:10
Speaker 1: and they have group theory as a foundation of their
15:12
Speaker 1: description of the fundamental particles. But if it's not, if
15:15
Speaker 1: instead we have some human element to this understanding, or
15:19
Speaker 1: that what's out there has no relationship, you know, to
15:22
Speaker 1: the model that we've built other than that it works,
15:24
Speaker 1: then maybe aliens would have completely separate ideas about physics.
15:29
Speaker 1: You think that's a reasonable way to frame this question
15:31
Speaker 1: of whether what we're probing is real, whether it could
15:33
Speaker 1: also exist in the minds of other intelligent creatures. Sure,
15:37
Speaker 1: I mean imagine first of all that at some stage
15:40
Speaker 1: in physics, um clever theorist story able to come up
15:44
Speaker 1: with two very different ways of categorizing phenomena, but they
15:50
Speaker 1: were equally predictively successful. Then I think the natural conclusion
15:54
Speaker 1: we would all draw, as it's underdetermined, at most one
15:57
Speaker 1: of these, if they're incompatible frameworks. Uh, at most one
16:00
Speaker 1: of these is true. Perhaps neither. Um we need more information.
16:05
Speaker 1: But one of the great, of course achievements of physics
16:08
Speaker 1: has been to increasingly try to break away from a
16:14
Speaker 1: narrowly provincially human way of looking at things. That's very
16:18
Speaker 1: difficult to do. And at some point I expect we'll
16:20
Speaker 1: come back to this. I think there are limits to
16:23
Speaker 1: how far one can go with that rationally, because at
16:27
Speaker 1: the foundation of the evidence for scientific theories, right the
16:31
Speaker 1: epistemology of science, are scientists in the activity of science.
16:35
Speaker 1: And we can't end up endorsing frameworks in which we
16:40
Speaker 1: cannot locate the rational inquirer in the community of inquirers
16:45
Speaker 1: and there and the activity of inquiring. And I have questions.
16:48
Speaker 1: It's very challenging. But you know, some of the more
16:51
Speaker 1: speculative attempts to unify fundamental particle physics and you know,
16:56
Speaker 1: large scale cosmology, I worry that they they're udding up against, um,
17:01
Speaker 1: these kinds of limits that they're they're positing models that
17:06
Speaker 1: we could imagine for some entirely disconnected reality. Right, they're
17:11
Speaker 1: perfectly coherent models for describing something, But could they describe
17:15
Speaker 1: our reality? Could we have reason to believe? Right? You know,
17:19
Speaker 1: there there, we are right in that question. Could we
17:21
Speaker 1: have reason to believe that we inhabit a world correctly
17:25
Speaker 1: depicted by this model? There's a tricky question there at
17:28
Speaker 1: the limit. It's certainly interesting to wonder about whether humans
17:31
Speaker 1: can imagine what humans can't imagine, right? Can we think
17:35
Speaker 1: our way out of our own box? It's it's certainly unknown.
17:38
Speaker 1: I'm really curious about the point you made earlier about
17:40
Speaker 1: whether there could be alternative and completely functional descriptions of
17:44
Speaker 1: the universe that are conceptually different. Like if I describe
17:48
Speaker 1: the universe with my theory of everything and it has
17:50
Speaker 1: squiggles in it, and I say, look, my theory works,
17:53
Speaker 1: squiggles must be real, and you know, you have your
17:55
Speaker 1: theory and it has squaggles in it, and you're like, no,
17:58
Speaker 1: squaggles are totally different from squiggles, and my predictions are
18:01
Speaker 1: just as good as yours. Then you're saying, we're faced
18:03
Speaker 1: with a question, are squaggles real? Are squiggles real? Is
18:06
Speaker 1: anything actually real? Is that the basic idea. And doesn't
18:09
Speaker 1: that sound very similar to the current situation about the
18:14
Speaker 1: nature of fundamental particles and the questions about quantum mechanics. Right,
18:17
Speaker 1: we have very very different conceptions of like what is
18:20
Speaker 1: real at the smallest scale, relational quantum mechanics, boney and mechanics,
18:24
Speaker 1: all apart from the you know, sort of orthodoxical Copenhagen interpretation,
18:28
Speaker 1: aren't we sort of in that situation. None of those
18:30
Speaker 1: theories give any real variation in their predictions, but they
18:34
Speaker 1: have completely different stories about what's happening in the microscopic scale.
18:38
Speaker 1: Does that mean that nothing is real or just that
18:40
Speaker 1: we haven't found which one is real? I think the latter,
18:43
Speaker 1: that we haven't found which one is real. And of
18:46
Speaker 1: course you're the expert here, not me, But I like
18:49
Speaker 1: to chat with the philosophers of physics and the occasional
18:52
Speaker 1: particle there theoretical physicist about the conceptual challenges in in
18:58
Speaker 1: quantum mechanics and in unifying quantum mechanics with space time theories,
19:04
Speaker 1: and so as I'm told. For example, so you've got
19:07
Speaker 1: this Bowman interpretation, one interesting feature of which is it's
19:11
Speaker 1: a deterministic theory about the dynamics of the universe, unlike
19:16
Speaker 1: at least a couple of the other leading theories. Whether
19:19
Speaker 1: or not we call many universe theory a deterministic theory
19:22
Speaker 1: is a somewhat subtle question, I think. But I'm told
19:25
Speaker 1: that while these four frameworks all have the same predictive
19:30
Speaker 1: consequences for the kinds of experiments we can do now
19:34
Speaker 1: or have done, that, there are in principle Bowman mechanics
19:38
Speaker 1: could have um different predictions, and so we could potentially,
19:43
Speaker 1: I don't know how far off this might be, but
19:45
Speaker 1: we could potentially have evidence that bore differentially between bow
19:50
Speaker 1: Mean mechanics and at least some of the alternatives. So
19:53
Speaker 1: that suggests, yeah, we don't know. So then we're just
19:56
Speaker 1: right currently, you know. But we're still interested in the question.
19:59
Speaker 1: It may not upen in our lifetime. So the question
20:01
Speaker 1: is should we be completely agnostic? And here the different
20:05
Speaker 1: theories have different kinds of theoretical virtues and vices. Insofars,
20:10
Speaker 1: one is willing to say purely general characteristics of theories
20:16
Speaker 1: in terms of simplicity of ontology and things like that,
20:21
Speaker 1: or whether it makes you requires you to make certain
20:25
Speaker 1: very outlandish seeming hypotheses, whether you give that any kind
20:30
Speaker 1: of evidential weight at all might determine whether or not
20:34
Speaker 1: you think we have reason to lean in one direction
20:37
Speaker 1: or the other, even if we don't have conclusive evidence. Well,
20:40
Speaker 1: I hope that experimentalists are clever enough to come up
20:42
Speaker 1: with ways to test these various hypotheses and tell us
20:45
Speaker 1: what's actually happening at the smallest scale one day. So
20:48
Speaker 1: I have a lot more questions for you, especially about emergence.
20:51
Speaker 1: But first let's take a quick break. All right, we're
21:06
Speaker 1: back and we're talking to Professor Tim O'Connor, philosopher of
21:09
Speaker 1: science and follow upon, Grand Champion of the World, who's
21:14
Speaker 1: answering my naive questions about philosophy of science and whether
21:17
Speaker 1: we can understand what's out there and whether it's real.
21:21
Speaker 1: I first came to read your work because I was
21:23
Speaker 1: very interested in the question of emergence cases where we
21:26
Speaker 1: can describe things we see in the world using rules
21:30
Speaker 1: that are very different from the rules of the underlying bits.
21:32
Speaker 1: It's like if you have a set of rules for
21:34
Speaker 1: how legos work, but once you put the legos together
21:36
Speaker 1: into complicated objects, you're better off describing their behavior in
21:39
Speaker 1: a new set of rules, like in a game of
21:42
Speaker 1: life where simple objects with simple rules come together and
21:45
Speaker 1: very complex behavior emerges. How would you define this concept
21:49
Speaker 1: of emergence and why in your views? Emergence and important
21:52
Speaker 1: question in philosophy of science. Yeah, so it's always been
21:56
Speaker 1: a controversial idea, and it emerged in the nineteenth century
22:00
Speaker 1: people began thinking, uh, in emergence terms of it's it's
22:04
Speaker 1: a question about the relationship of science at different levels
22:07
Speaker 1: of grain. So, how does physics relate to chemistry, chemistry
22:12
Speaker 1: to molecular biology, biology to organismic biology, and and so,
22:16
Speaker 1: and then our biology to human psychology neuroscience and the
22:20
Speaker 1: brain to human psychology. And the emergent test is a
22:25
Speaker 1: person who, in very general terms thinks that organization of
22:30
Speaker 1: certain kinds gives rise to new features, new new patterns
22:36
Speaker 1: that have a certain degree of autonomy with respect to
22:40
Speaker 1: the lower level underlying dynamics. It's a new form of
22:44
Speaker 1: dynamics of patterns that the kinds of concepts you need
22:48
Speaker 1: to describe what's going on are different than the kind
22:50
Speaker 1: of concepts you need to do the lower level science.
22:53
Speaker 1: And uh. Left at that um that there is emergencies
22:58
Speaker 1: entirely uncontroversial. There is such a thing as chemistry, and
23:01
Speaker 1: chemistry can be understood to a degree, at least at
23:05
Speaker 1: an elementary level apart from quantum mechanics, and certainly biology
23:09
Speaker 1: can be understood without knowing anything about quantum physics and psychology,
23:14
Speaker 1: you know, you one can even do psychology of various kinds,
23:18
Speaker 1: of social psychology, of normal psychology, and so on without
23:22
Speaker 1: knowing anything about physics or chemistry. So there are patterns
23:25
Speaker 1: in the world that have to do with organized systems
23:28
Speaker 1: of a certain kind, robust patterns, patterns where you can
23:31
Speaker 1: predict phenomena. I mean, think about the fact that if
23:33
Speaker 1: I were to go agree to fly out to California
23:37
Speaker 1: to meet up with you, and three days later I
23:40
Speaker 1: show up at your office door, and you quite confidently
23:44
Speaker 1: believe that that's going to happen, And that involves the
23:48
Speaker 1: movement of a hunk of matter that's coalesced in a
23:52
Speaker 1: fairly organized way, transporting itself across a great deal of distance.
23:57
Speaker 1: And could you predict that in terms of physics, Well,
24:01
Speaker 1: certainly not, given your and given our computational limits. Right,
24:06
Speaker 1: But you know, psychology works beautifully well, right, I mean,
24:08
Speaker 1: we can predict human behavior to a certain degree just
24:12
Speaker 1: by attributing to people beliefs, desires, intentions, uh, and so on,
24:18
Speaker 1: and you can be completely ignorant. People were doing this
24:22
Speaker 1: a thousand years ago, knowing nothing about the physical, underlying
24:26
Speaker 1: physical structure of the world. So there's a sense in
24:29
Speaker 1: which it's it's obviously true that there are emergent phenomena.
24:34
Speaker 1: So weak emergence is the uncontroversial kind. Weak emergence says
24:38
Speaker 1: there are organized phenomena that have their own characteristic forms
24:43
Speaker 1: of activity, their own characteristic features, and the kind of
24:47
Speaker 1: dynamics for how how this activity unfolds. But the weak
24:51
Speaker 1: emergentis says all of that is fixed, in some sense
24:56
Speaker 1: determined by the underlying most fundamental dynamics in our world,
25:02
Speaker 1: the fundamental physical dynamics, whatever that turns out to be,
25:06
Speaker 1: you know that lies at the root of everything. Fix
25:11
Speaker 1: that across space and time, all the fundamental physics, right,
25:15
Speaker 1: and you've thereby fixed all higher level phenomena in their patterns. So,
25:19
Speaker 1: for example, like we're playing a game of ping pong,
25:21
Speaker 1: or saying that we can describe the motion of the
25:23
Speaker 1: ping pong ball using fairly simple rules, but fundamentally, even
25:27
Speaker 1: though we can't calculate it today, those basic rules of
25:29
Speaker 1: the ping pong ball come from the basic rules of
25:32
Speaker 1: its constituents. That the twoing and throwing of all the
25:34
Speaker 1: particles inside the ping pong ball adds up somehow to
25:37
Speaker 1: F equals M A that is determined by the basic elements.
25:41
Speaker 1: Is that is that the idea? Yes, And it's just
25:44
Speaker 1: you know, computational limits on our part that we can't
25:47
Speaker 1: discern it all right, So laplace the nineteenth century physicist mathematician,
25:53
Speaker 1: you know, famously imagined a kind of disembodied intelligence who
25:58
Speaker 1: had with subjects eurocomputational limits, right, could track all the
26:04
Speaker 1: fundamental entities constituting space and time and their trajectories, and
26:08
Speaker 1: discern the patterns the fundamental dynamics that drive those things
26:13
Speaker 1: their interactions. And then the thought is you could, so
26:17
Speaker 1: to speak, step back, uh and see the forest for
26:20
Speaker 1: the trees, and could also notice then that there are
26:23
Speaker 1: these structured uh features of of you know, more larger
26:28
Speaker 1: regions of space and time and their interactions, and and
26:32
Speaker 1: discern they have dynamics, and could in a very lorious
26:35
Speaker 1: way for us at any rate, show that these high
26:38
Speaker 1: level patterns don't disturb you might say, or add to
26:42
Speaker 1: what's going on at the fundamental level, they're just a
26:46
Speaker 1: structured consequence of it. It's a surprising fact why we
26:49
Speaker 1: could imagine a boring flat world where there's just fundamental
26:53
Speaker 1: physics but there was no interesting structured phenomena um, while
26:57
Speaker 1: our world is not like that. And so that gives
26:59
Speaker 1: rise to an interesting question even for the weak emergence.
27:02
Speaker 1: So why is our world such that there are not
27:05
Speaker 1: just fundamental physical patterns that fix everything, but also these
27:11
Speaker 1: higher levels structured phenomena. It seems conceivable that that there
27:15
Speaker 1: could be alternative physics where that just never happens. So
27:19
Speaker 1: to me, that's a that's a really fascinating question. I
27:21
Speaker 1: can't let you go past that without exploring it more deeply.
27:23
Speaker 1: To me, that's one of the deepest questions. Like in
27:26
Speaker 1: the weak emergent case, where everything is determined by the
27:28
Speaker 1: most fundamental principles, why is it then possible to find
27:33
Speaker 1: this structure? Why is it possible to find fairly simple
27:36
Speaker 1: mathematical laws with hugely reduced degrees of freedom? Right when
27:39
Speaker 1: you talk about the ping pong ball and moving across
27:41
Speaker 1: the table, you don't have to talk about all the
27:43
Speaker 1: particles that are inside of it, as you say, there
27:46
Speaker 1: are these simpler descriptions of structure that emerges. Is it
27:50
Speaker 1: necessary that structure emerges? Why isn't it just the fundamental
27:53
Speaker 1: bits and then basically chaos above that? You know, Why
27:56
Speaker 1: isn't everything like a hurricane out of rain drops and
27:59
Speaker 1: possible to predict no larger structure? Why does it these
28:03
Speaker 1: simple explanations emerge. Do we understand that? To the best
28:05
Speaker 1: of my knowledge? And no, since I've never encountered anyone
28:10
Speaker 1: the many thinkers, scientists and philosophers who talk about emergence
28:14
Speaker 1: who directly address that question and give kind of a full,
28:18
Speaker 1: plausible sounding answers to it. And I'm almost thinking it's
28:22
Speaker 1: a question for a mathematician or a physicist, you know,
28:28
Speaker 1: kind of where's dual hats? As a mathematician, I mean,
28:31
Speaker 1: so you you invoked the game of life. So John Conway,
28:34
Speaker 1: famous mathematician, Uh, he described this the cellular automata, which
28:40
Speaker 1: sounds complicated, but it's actually quite simple, right. It's like
28:43
Speaker 1: it's almost like describing a reality, a two dimensional reality
28:48
Speaker 1: that has very very simple property, so simple, much simpler
28:51
Speaker 1: than fundamental physics. But what's really interesting about it is
28:55
Speaker 1: he shows that depending on the initial conditions you said,
28:58
Speaker 1: and then you just watch how grid changes over time.
29:02
Speaker 1: Moment to moment, patterns emerge, Structured patterns emerge that don't
29:06
Speaker 1: alter the basic rules of life are unchanged, and yet
29:10
Speaker 1: there are these interesting patterns that can be understood in
29:13
Speaker 1: their own terms. That way of framing at this very
29:16
Speaker 1: elementary mathematical he should he shows it that it happens
29:20
Speaker 1: in certain life worlds. You get these interesting patterns, and
29:24
Speaker 1: then the question is whether it's almost sounds like the
29:27
Speaker 1: territory of a mathematical proof of certain fundamental dynamics subject
29:33
Speaker 1: to certain constraints that can be given a clear mathematical description,
29:39
Speaker 1: necessarily will yield over um, given enough times, patterns of
29:45
Speaker 1: structured interactions. At least, That's why I'm tempted to say
29:49
Speaker 1: it's it's it's almost it's that kind of question. It's
29:51
Speaker 1: fascinating to me. And you know, maybe, like the weakest
29:54
Speaker 1: argument I could make to say that structure has to
29:57
Speaker 1: emerge is that, well, maybe it doesn't a is, but
30:00
Speaker 1: we exist in the universe where it has, because otherwise
30:03
Speaker 1: we couldn't. I mean, we are structure right my mind,
30:06
Speaker 1: my concept of myself, this conversation all of this is
30:09
Speaker 1: emerging structure. I'm not a fundamental bit in the universe.
30:12
Speaker 1: Neither you neither as humanity, maybe not you know consciousness,
30:16
Speaker 1: So perhaps you know there are many universes out there,
30:18
Speaker 1: and only in ones where structure does emerge at larger
30:21
Speaker 1: scales can you have consciousness and podcasts and philosophy at
30:25
Speaker 1: those scales. That seems to be sort of a very
30:28
Speaker 1: weak argument. In physics, we have another concept, which is
30:31
Speaker 1: normalization theory, which lets us say the theory we have
30:34
Speaker 1: about particle physics right now is an effective theory. We
30:37
Speaker 1: know that we know that electrons and quirks are probably
30:40
Speaker 1: not the answer to the deepest question in the universe.
30:43
Speaker 1: But we can abstract away all the really high energy stuff,
30:45
Speaker 1: the stuff we can't probe today, the smaller bits in
30:48
Speaker 1: terms of a few parameters, and Robert Wilson theory about
30:51
Speaker 1: renewalization and all of this stuff and the decoupling theorem
30:54
Speaker 1: lets us do this. But we don't really understand to
30:57
Speaker 1: my knowledge why that is. It seems to it's sort
31:00
Speaker 1: of like science and a larger scale. It seems to work.
31:02
Speaker 1: We have these abilities to do this, but there's no
31:05
Speaker 1: theory as far as I can tell, that tells us
31:07
Speaker 1: why that happens. I mean, it's in another way, if
31:10
Speaker 1: I gave you a fundamental description of the universe, could
31:12
Speaker 1: you predict whether or not emergence comes out of it,
31:15
Speaker 1: whether or not things emerge, or would you have to
31:18
Speaker 1: run the simulation and observe it. To me, that's a
31:20
Speaker 1: really interesting question. You know, why this stuff emerges at all? Yes,
31:25
Speaker 1: And then of course there's the question of a different
31:28
Speaker 1: kind of emergence. So strong emergence, which is non trivial,
31:34
Speaker 1: it's not trivially manifest, is a notion of when under
31:39
Speaker 1: certain structured conditions, properties of holes arise and they have
31:44
Speaker 1: an influence on how things behave. And these properties do
31:50
Speaker 1: uh add at the end of the day, and they
31:53
Speaker 1: add to the fundamental dynamics of the world. They have
31:56
Speaker 1: a kind of downward influence, and it goes all the
31:59
Speaker 1: way down right. So it's as if it's a new force,
32:03
Speaker 1: like property or something. I mean, how exactly we might
32:06
Speaker 1: theorize such an irreducible property, irreducible but causing the effective property.
32:12
Speaker 1: Perhaps there's more than one way we could do it.
32:14
Speaker 1: But you know, just as a kind of rough and
32:15
Speaker 1: ready initials start. You know, think of it as like
32:18
Speaker 1: a new kind of structured force property or something that
32:22
Speaker 1: adds to But this is sort of a shocking idea
32:25
Speaker 1: to me, because as a particle physicist, I imagine a
32:28
Speaker 1: reductionism works. If I want to understand big stuff, I
32:30
Speaker 1: go to the small stuff, and I eventually I can
32:32
Speaker 1: build up from there if I have infinite computing power, etcetera.
32:35
Speaker 1: And you're suggesting that's not necessarily the case, that maybe
32:38
Speaker 1: there are rules that exist at the higher level, of
32:40
Speaker 1: the level of ping pong balls and ice cream, that
32:43
Speaker 1: don't come out of the smallest bits, but somehow exists
32:46
Speaker 1: only at that level. Is that right? Yeah? And and
32:49
Speaker 1: so then I want to say, you know, it's an
32:50
Speaker 1: empirical question. It ought to be thought of as a
32:53
Speaker 1: straightforwardly empirical question whether there are emergent properties of that kind,
32:57
Speaker 1: emergent properties and patterns and activity of of that stronger variety.
33:02
Speaker 1: And for that I don't think fundamental physics is the
33:07
Speaker 1: domain you go to, or certainly not by itself. I mean,
33:11
Speaker 1: if we were Laplasians, pure disembodied infinite intelligence, well we
33:16
Speaker 1: could we could do do it and say, well do
33:19
Speaker 1: it do I is there any region of space time
33:22
Speaker 1: we're running only with the fundamental dynamics breaks down right
33:28
Speaker 1: in certain interestingly structured local regions, right, But we're not
33:34
Speaker 1: such an intelligence and so and it's inconceivable at present
33:38
Speaker 1: and probably forever, that we could directly monitor in real
33:43
Speaker 1: time trillions upon trillions of variables corresponding to all the
33:48
Speaker 1: particles both in and immediately within the light cone over
33:52
Speaker 1: an interval of time, you know, some some sort of
33:54
Speaker 1: organized phenomena and calculate, you know what, how we expect
33:58
Speaker 1: all those interactions to go and see whether the particle
34:01
Speaker 1: physics is sufficient for capturing what's going on in say
34:04
Speaker 1: a human brain, to pick a likely target of a
34:08
Speaker 1: strong emergences hypothesis. Right, And so that's a very attractive
34:12
Speaker 1: question obviously. You know, we look at the human brain
34:15
Speaker 1: and it's a lump of stuff. There are other lumps
34:17
Speaker 1: of stuff that don't seem to be conscious. You know,
34:19
Speaker 1: my desk, my chair are also lumps of stuff to
34:22
Speaker 1: have actually the same you know, number of protons and
34:25
Speaker 1: neutrons and electrons as my brain does. Why is it
34:28
Speaker 1: that my brain exhibits this crazy behavior that rocks and
34:31
Speaker 1: chairs and tables don't. So are you suggesting that, for example,
34:35
Speaker 1: consciousness might not just emerge from the interactions of those
34:40
Speaker 1: pieces inside the brain, but could come out at some
34:42
Speaker 1: sort of higher level. Yeah, and so here's where I
34:46
Speaker 1: would say, contentiously, we're kind of in the realm of philosophy.
34:50
Speaker 1: But when you reflect on the nature of conscious experience,
34:53
Speaker 1: we seem directly acquainted with qualities. Qualities of our own
34:59
Speaker 1: experience says that cannot plausibly, perhaps even conceivably be mapped
35:05
Speaker 1: onto structured properties of the relevant regions of our brain.
35:10
Speaker 1: So you know, famous kind of example, if you if
35:13
Speaker 1: you go into the philosophy literature talking about this, you
35:16
Speaker 1: encounter the story of this neuroscientist Mary, and Mary is
35:21
Speaker 1: we imagine a hundred years from now the science of
35:24
Speaker 1: the neuroscience of color vision is complete, and uh so
35:30
Speaker 1: Mary is a credential neuroscientist of color vision. So what
35:36
Speaker 1: that means is you put somebody on an under the
35:40
Speaker 1: relevant scanning device and Mary gets some kind of interpreted
35:45
Speaker 1: feed out from from her computer telling her what's going
35:49
Speaker 1: on structurally, and she can predict what kind of color
35:53
Speaker 1: experience the person is having just on the basis of
35:56
Speaker 1: that But now here's the wrinkle you add to the story.
35:59
Speaker 1: Mary herself is ever had color experience because Mary Mary's
36:03
Speaker 1: parents were crazy psychologist who thought it was an interesting
36:07
Speaker 1: experiment to raise her to be both a scientist of
36:10
Speaker 1: color vision, but to never have So she only has
36:12
Speaker 1: monochrome shades of gray, right everything. And she's locked in
36:16
Speaker 1: a room and she she does there's nothing that has
36:19
Speaker 1: color beyond shades of gray and white and black. She's
36:23
Speaker 1: never cut herself, She's happily has never cut herself. She
36:27
Speaker 1: never thought to do that. But one day, you know,
36:30
Speaker 1: she escapes from her room and she looks out on
36:32
Speaker 1: a bright sunny day and sees a red rose. And
36:35
Speaker 1: she knows that when human beings look at roses right,
36:40
Speaker 1: that they have what she calls red color experience. But
36:44
Speaker 1: for her, it's a purely theoretical quality. What is that
36:46
Speaker 1: the way red looks to a normally sighted human under bright,
36:51
Speaker 1: sunny conditions. So now she has the experience, and she
36:54
Speaker 1: says to herself, so that is what a red rose
36:58
Speaker 1: looks like. That is she's not learning something about the
37:02
Speaker 1: color of the rose. That's that has to do with
37:05
Speaker 1: the surface of the rose. Right, kind of certain reflectance property.
37:10
Speaker 1: That's not what she exclaims. She's actually talking about her
37:12
Speaker 1: own experience of a red rose. She's saying, that's what
37:16
Speaker 1: an experience of redness is like for a human being,
37:21
Speaker 1: you know. And we think about that thought experiment, and
37:23
Speaker 1: we think it makes perfect sense, and we say, right,
37:26
Speaker 1: somebody who who's never experienced the color red, you can't commune.
37:30
Speaker 1: It's kind of ineffable. There's just this simple quality, right,
37:35
Speaker 1: of a certain kind of deep red color, let's say,
37:38
Speaker 1: as opposed to a blue and green. Right, These are
37:41
Speaker 1: just they're just different. They're distinct qualities, but the relatively
37:44
Speaker 1: simple qualities of our experiences right now. That the physics
37:47
Speaker 1: of it, of course, is that photons hate your eyeballs
37:50
Speaker 1: at different energies, different wavelengths, and they'll stimulate, you know,
37:53
Speaker 1: different paths at different signals of the optic nerve. But
37:57
Speaker 1: of course there's no color in those signals. Right. The
38:00
Speaker 1: color you're saying is experienced by the brain. It gets
38:02
Speaker 1: the signal and it gives you the experience of red
38:05
Speaker 1: or the experience of blue. You're saying, that internal experience.
38:09
Speaker 1: We don't know how to describe it, or quantify it
38:11
Speaker 1: or make it objective, but but it's real, and it's
38:14
Speaker 1: something over and about. Mary seems to learn something new
38:17
Speaker 1: about color experience, even though she knew every what you
38:19
Speaker 1: were just describing in shorthand. Harry knows all that stuff.
38:22
Speaker 1: She she knows the neuroscience of color experience. She knows
38:25
Speaker 1: what goes on in the visual cortex. Right, what kind
38:28
Speaker 1: of patterns of firings of neurons are going on when
38:31
Speaker 1: someone has an experience like that? Right, But those seem
38:34
Speaker 1: to be all the causal preconditions, the underpinnings of color experience,
38:39
Speaker 1: but not the experience itself, the subjective of the simple
38:42
Speaker 1: subjective quality. So the suggestion is right, there are these
38:47
Speaker 1: subjective qualities, qualities of conscious minds, experiential qualities, but are
38:53
Speaker 1: something over and above the physical structures and states and
38:57
Speaker 1: processes that undoubtedly our nest necessary to have to undergo
39:01
Speaker 1: those experiences. There's something additional. They seem strongly emergent, because
39:06
Speaker 1: now we're not just talking about a pattern of activity.
39:08
Speaker 1: We're talking about a new fundamental quality that can't be
39:12
Speaker 1: described in terms of any of these sorts of processes,
39:17
Speaker 1: even at the neuroscientific level of description, which would seem
39:20
Speaker 1: to be the relevant level of description here, right, that's
39:23
Speaker 1: if it is a wholly physically constituted phenomena, then neuroscience
39:28
Speaker 1: should be the science that tells you what it is.
39:31
Speaker 1: It's that neural structure and patterns. So you describe this
39:35
Speaker 1: as an empirical question, what is the empirical test you
39:38
Speaker 1: could do to figure out whether consciousness or you know,
39:42
Speaker 1: even physics of baseballs is strongly emergent or weakly emergent,
39:47
Speaker 1: whether it is something new at these larger scales, or
39:50
Speaker 1: whether this is determined by the little bits that they're
39:52
Speaker 1: made out of. Right, Well, it would seem like we
39:55
Speaker 1: would need a much you know, neuroscience is still in
39:59
Speaker 1: its RelA to infancy. If you talk to neuroscientists, that's
40:02
Speaker 1: what they say about the state of the science. They
40:05
Speaker 1: know a lot about local interactions and so on, neurons
40:09
Speaker 1: and synapses and all that, but large scale patterns um
40:13
Speaker 1: is something that they're just beginning to get a bit
40:16
Speaker 1: of a handle on. There's a ton that they don't understand.
40:19
Speaker 1: But it would seem like if we could envision a
40:22
Speaker 1: much more developed systematic neuroscientific theory of neural dynamics of
40:29
Speaker 1: brains as complicated as our brains, and you could show
40:34
Speaker 1: that you could completely predict the unfolding of the relevant processes,
40:40
Speaker 1: say in the visual cortex, when someone's having color experience,
40:43
Speaker 1: without recurse to some hypothesized further quality that presumably would
40:49
Speaker 1: be doing something. That is, if the look of a
40:52
Speaker 1: red rose really is a quality over and above some
40:55
Speaker 1: kind of structured neural quality, then that quality is part
41:02
Speaker 1: of what leads me to talk about it. Right, So
41:06
Speaker 1: that means that in principle, a neuroscientist who's paying attention
41:10
Speaker 1: in real time what's going on in your brain when
41:13
Speaker 1: all this is happening, you're having experience and you're talking
41:15
Speaker 1: about it, if the theory was sufficiently well developed and testable,
41:20
Speaker 1: could see whether somehow there was an incompleteness, you know,
41:25
Speaker 1: if the if the neuroscientists just just doing it in
41:27
Speaker 1: terms of neurons and neural assemblies and so forth, and
41:31
Speaker 1: they can perfectly predict the dynamics going on in the
41:34
Speaker 1: relevant portion of your brain without recourse to some further hypothesized, holistic,
41:39
Speaker 1: strongly immersion property. But in fact, suppose suppose that's just wrong.
41:43
Speaker 1: It's an illusion, but it's somehow hardwired into us that
41:46
Speaker 1: we have this illusion. If there's something further that's left
41:49
Speaker 1: out of a physical description that's a conceivable, you might
41:53
Speaker 1: say it's a psychological hypothesis. Right, one could go looking
41:57
Speaker 1: for there's something about the way our our psychology structured
42:01
Speaker 1: such that you know, you know, we know there are
42:02
Speaker 1: visual illusions built into our visual system, the Mueller lie,
42:07
Speaker 1: the you know, the two lines with arrows. I won't
42:10
Speaker 1: go into a description right there, there's well known visual
42:13
Speaker 1: illusions that have to do with certain limits to our
42:17
Speaker 1: visual system. Right, we're led to say untrue things about
42:21
Speaker 1: what we're experiencing. Maybe maybe there's something like this that's
42:24
Speaker 1: even deeper. Right, we're inclined to attribute qualities to experiences
42:29
Speaker 1: that aren't actually there, right, and so if they're not there,
42:33
Speaker 1: then boom, the problem goes away. Okay, great, So so
42:36
Speaker 1: you know a scientists, you know, who's kind of reductionist
42:38
Speaker 1: minded should be tempted by this illusionist perspective unconscious experience.
42:43
Speaker 1: We're having experiences, it's just they're not what they seem
42:47
Speaker 1: to us to be. And to me, that connects really
42:49
Speaker 1: deeply with this larger question of what's out there? And
42:52
Speaker 1: do we know that what we are experiencing, the theories
42:55
Speaker 1: we're building from those experiences really reflect what's real in
42:58
Speaker 1: the universe, or whether it's just us to sort of
43:00
Speaker 1: game we're putting together in our minds, um And so
43:03
Speaker 1: I want to ask you more about that, but first
43:05
Speaker 1: let's take another quick break. Okay, we're back and we're
43:20
Speaker 1: talking with Professor Tim O'Connor, who's telling us about how
43:24
Speaker 1: things emerge in the world and how we can explore
43:26
Speaker 1: them and most importantly, what that tells us about what's
43:29
Speaker 1: real out there in the universe. And to me, this
43:32
Speaker 1: question of emergence is very closely connected to the question
43:35
Speaker 1: of scientific realism, because even if you believe that the
43:38
Speaker 1: universe is real and there are basic bits and rules
43:40
Speaker 1: about those basic bits, if you take the weak emergence,
43:43
Speaker 1: we haven't learned what those basic bits are. We've only
43:46
Speaker 1: learned the emergent bits. So in the question of scientific
43:49
Speaker 1: realism of what's out there in the universe, how do
43:51
Speaker 1: we know that what has emerged is real or whether
43:55
Speaker 1: it's just sort of like our description of it. Even
43:58
Speaker 1: if there is a real un verse out there, and
44:01
Speaker 1: if we drill down with the biggest particle collider or
44:03
Speaker 1: anybody could ever build. We might find something deep and true.
44:06
Speaker 1: How do we know that what's emerged on top of
44:08
Speaker 1: that is real? Is it possible that the way things
44:11
Speaker 1: emerged to us might be different than the way things
44:15
Speaker 1: emerge to another intelligent race that is a different set
44:18
Speaker 1: of senses, For perhaps it perceives the universe through different
44:22
Speaker 1: fundamental physics properties. How do we know the emergent pieces themselves?
44:26
Speaker 1: We can you know, say, are actually out there? Good? Um? Right,
44:30
Speaker 1: so it seems, you know, in the abstract, it seems
44:34
Speaker 1: conceivable that there be different but equally effective course scrained ways.
44:41
Speaker 1: You might say of chunking up you know, things that
44:43
Speaker 1: the level of middle sized objects and observers, But just
44:46
Speaker 1: the categories are different. Um, so you know, we find
44:51
Speaker 1: it natural to group things. Let me acknowledge right at
44:53
Speaker 1: the outside, or I think we all should acknowledge our senses, right,
44:58
Speaker 1: Our categories are closely tied to our perceptual senses, and
45:02
Speaker 1: our senses are geared to be good at we know
45:06
Speaker 1: detecting features that are useful to us, or at least
45:10
Speaker 1: we have reason right to believe they would have evolved.
45:12
Speaker 1: And so you know, this could kind of add scientific
45:16
Speaker 1: reason to be a little bit worried about this question.
45:19
Speaker 1: It say, certain things get foreground in our experience because
45:23
Speaker 1: they they're really important to us. You know, colors are
45:27
Speaker 1: signals to us of you know, food sources and properties
45:32
Speaker 1: for example, and probably a lot of other things I
45:34
Speaker 1: don't even know about. But maybe to a different kind
45:36
Speaker 1: of a non carbon based kind of inquirer who doesn't
45:39
Speaker 1: need organic food sources, maybe color might not be the
45:43
Speaker 1: same same sale sort of property, but other properties that
45:47
Speaker 1: do have relevance to its survival and its ability to
45:50
Speaker 1: navigate its environment would be foreground. And for us, we
45:53
Speaker 1: don't kind of see, we don't. We don't tend to
45:56
Speaker 1: pick out those patterns, and so it leads yeah, and
45:58
Speaker 1: then you know, you generalize the picture. And then so
46:02
Speaker 1: then the two different types of enquirers, the organic ones
46:05
Speaker 1: like us and the non organic silicon based ones that
46:09
Speaker 1: we could imagine their whole way of representing middle sized
46:13
Speaker 1: environmental features and patterns somehow different, but they get along
46:17
Speaker 1: well in their environment that they're able to do science.
46:19
Speaker 1: And so suppose we're at roughly the same level of
46:23
Speaker 1: scientific advancement, and so we have rather similar fundamental physics,
46:28
Speaker 1: but we're different. Maybe that's what you're asking, you know,
46:31
Speaker 1: at the at the level of kind of more emergent levels.
46:34
Speaker 1: But there's also there's a question here a scale, because
46:36
Speaker 1: when we talk about emergence, I think you're probably thinking
46:39
Speaker 1: about me and you and ice cream, ping pong balls.
46:41
Speaker 1: But for the particle physicists, I'm even talking about electrons.
46:45
Speaker 1: I'm talking about corks, which we think are probably emerging
46:48
Speaker 1: from something you know, mind bogglingly even deeper in the universe.
46:51
Speaker 1: So basically everything we've ever learned is emerging. We have
46:55
Speaker 1: no knowledge of the fundamental and we don't even know
46:57
Speaker 1: if there is something fundamental. Maybe there isn't Maybe it's
46:59
Speaker 1: a infinite tower of effective theories all the way down.
47:03
Speaker 1: There is no deep truth. How do we know that
47:05
Speaker 1: our tower will line up with alien towers or if
47:09
Speaker 1: they have another way of looking at what you call
47:11
Speaker 1: coarse grained theories of the universe where to me, course,
47:14
Speaker 1: grain could be as small as an electron or as
47:16
Speaker 1: large as a planet. Yeah, I don't know if this
47:20
Speaker 1: fully Uh, it certainly doesn't fully address your question, but
47:23
Speaker 1: I would want to throw out the following constraint unless
47:27
Speaker 1: we become complete systematic skeptics about human knowledge and say,
47:33
Speaker 1: you know, I don't even know whether or not I'm dreaming,
47:36
Speaker 1: or even more radically, you know Descartes way back in
47:39
Speaker 1: the seventeenth century, perhaps perhaps I'm just a disembodied mind
47:43
Speaker 1: and I have a false beliefs about my own past.
47:46
Speaker 1: In fact, there is no physical world. I wasn't born,
47:49
Speaker 1: none of this, and there's just some evil genius spent
47:51
Speaker 1: on deceiving me who's pumping my mind with a flow
47:55
Speaker 1: of stream of experience that I naturally interpret as my
48:00
Speaker 1: in interacting with my physical environment. But none of it's there, right,
48:04
Speaker 1: or you know the matrix films, you know, our kind
48:07
Speaker 1: of updated version of this, you know the way things
48:10
Speaker 1: really are, that what really lies behind our experiences is
48:14
Speaker 1: something very different from what we naively take it to be. Well,
48:18
Speaker 1: you can't do science under those ground rules, right. Science
48:22
Speaker 1: has to presuppose, for example, that we didn't pop into
48:26
Speaker 1: existence just thirty seconds ago with a bunch of you know,
48:30
Speaker 1: built in false memories about having had past experience. Science
48:34
Speaker 1: has to presuppose that there's some kind of regularity to
48:40
Speaker 1: the way the world unfolds. And if you say, well, no,
48:44
Speaker 1: science can show that there's regularity by doing experiments and
48:49
Speaker 1: you know, corroborating results. That presupposes that what you're hearing
48:54
Speaker 1: when you're being informed by another scientist about their results
48:58
Speaker 1: itself reflects the um outputs of another scientist. But why
49:02
Speaker 1: are you trusting your senses? Right? That's a really big assumption.
49:06
Speaker 1: That your senses are even effectively registering anything outside you
49:10
Speaker 1: is a big assumption. Well, you can't scientifically verify that, right,
49:14
Speaker 1: because you'd have to somehow get outside of your senses.
49:16
Speaker 1: You can't do that. You can't get outside of your
49:19
Speaker 1: rational thinking. So the point is, even what we think
49:21
Speaker 1: of as a paradigm of rational inquiry, science has to
49:25
Speaker 1: make certain foundational assumptions about the rough and ready, at
49:29
Speaker 1: least reliability of our basic cognitive equipment, and the rough
49:34
Speaker 1: and ready predictability or patterned nous of the world that
49:38
Speaker 1: we're seeking to describe. It doesn't have to assume a
49:41
Speaker 1: lot more than that, but it doesn't have to assume
49:43
Speaker 1: at least those things. And it has to assume if
49:49
Speaker 1: science is going to deliver a rational set of beliefs
49:53
Speaker 1: of us, that we exist, that we persist, that we
49:56
Speaker 1: really are interacting with one another. Well, but once you
50:00
Speaker 1: once you do that, when now we've got I exist,
50:02
Speaker 1: you exist if we're fellow scientists, I'm part of this community,
50:06
Speaker 1: just this distributed community. I have to assume, since I
50:11
Speaker 1: can't do all the science myself, no scientists can do that,
50:14
Speaker 1: that there is this rational community that's effectively managing to
50:18
Speaker 1: communicate results and theories and descriptions and how they corroborate
50:23
Speaker 1: with theories. A lot is getting baked in my point.
50:26
Speaker 1: I guess that is what I'm getting at here has
50:28
Speaker 1: to be baked in for Steve and ask an interesting
50:31
Speaker 1: question about have our theories delivered the rational goods? Now?
50:37
Speaker 1: Making those assumptions doesn't require that. Chemistry or biology as
50:42
Speaker 1: we know it is very closely tracks the truth at
50:46
Speaker 1: that level of description. So I'm not suggesting we get
50:50
Speaker 1: our emergent phenomena. But there there are constraints. You can
50:53
Speaker 1: either be a total skeptic or you have to say
50:55
Speaker 1: there are enquirers that have certain capacity of these and
51:01
Speaker 1: uh certain reasonable assumptions that they make. I'm not sure
51:04
Speaker 1: how far that gets us, but it gets us a
51:06
Speaker 1: certain ways. I think you're making the point that we
51:09
Speaker 1: can take our skepticism and paranoia too far in throwing
51:13
Speaker 1: out everything and saying we can know nothing, um. And
51:16
Speaker 1: it's certainly the case that, you know, we would like
51:19
Speaker 1: to know something that's true about the universe. But I
51:21
Speaker 1: think the motivation for examining these fundamental in the foundations
51:26
Speaker 1: of our knowledge and how we know things is because
51:28
Speaker 1: we wonder if we've make it made a mistake, if
51:31
Speaker 1: we've made some arbitrary choices where we could have perhaps
51:34
Speaker 1: if Plato had a different mood, you know, founded intellectual
51:38
Speaker 1: thought in another direction, and everything would have been built
51:40
Speaker 1: up and conceived up in a completely different way. And
51:42
Speaker 1: to me, that's what's exciting about potentially meeting alien physicists,
51:46
Speaker 1: or even digging back into ancient human knowledge and seeing
51:50
Speaker 1: how independent communities the Mayans, the Egyptians of Chinese thought
51:54
Speaker 1: about their the universe and their relationship to it, you know,
51:57
Speaker 1: separately from from each other. Because it seems to me
52:00
Speaker 1: like it's possible, and it's fascinating to me that it's
52:02
Speaker 1: possible that the way we've built our ideas of physics
52:05
Speaker 1: and the universe could have some arbitrary nous to it, right,
52:09
Speaker 1: that there could be another way to have done this.
52:12
Speaker 1: So to me, it's exciting to probe those and to
52:14
Speaker 1: do the impossible thing that we suggested earlier, which is
52:16
Speaker 1: to imagine what humans haven't yet or maybe cannot yet imagine.
52:20
Speaker 1: So let me ask you the last question, what do
52:22
Speaker 1: you think are the prospects for making progress? I mean,
52:25
Speaker 1: we've been talking about whether the universe out there is
52:28
Speaker 1: real or just imagined since the matrix, since um, you know,
52:32
Speaker 1: the card, since Plato in fact, so it's been thousands
52:36
Speaker 1: of years we've been thinking about these questions. Is it
52:38
Speaker 1: a question we'll be thinking about forever or are we
52:40
Speaker 1: likely to see breakthroughs where one day we say, oh,
52:43
Speaker 1: look we settled that question. Plato was right or Plato
52:46
Speaker 1: was wrong, and then we can move on to other questions.
52:49
Speaker 1: What do you think, Well, we won't settle it in
52:51
Speaker 1: the sense that, um, there's never the basis for a
52:58
Speaker 1: somewhat reasonable worry or skepticism that we haven't mailed it down.
53:04
Speaker 1: There's always because we're a scientific human inquiry generally, and
53:09
Speaker 1: science as a special rigorous case of human inquiry is fallible.
53:13
Speaker 1: There's no reason to believe they're perfect. So that's if
53:17
Speaker 1: if we lower our sites and uh, get away from
53:21
Speaker 1: having a perfect congruence, a perfect mapping of reality. Maybe
53:26
Speaker 1: we'll never get that, but we have a closer and
53:29
Speaker 1: closer mapping than that. That's good enough. Well, it certainly
53:34
Speaker 1: is helping us, you know, develop new technologies and I
53:38
Speaker 1: hope revealing something that's true about what's out there in
53:41
Speaker 1: the universe. To me, I love these moments of insight
53:43
Speaker 1: and discovery where we feel like not just that we've
53:46
Speaker 1: developed some new tool that describes the universe, but we're
53:49
Speaker 1: actually revealing its internal it's underlying mechanism. You know that
53:53
Speaker 1: the ex boson, for example, is actually out there and
53:56
Speaker 1: is doing and frowing and doing. It's a bit to
53:58
Speaker 1: create mass for all the other particle and not just
54:00
Speaker 1: a mathematical description that we have in our heads, because
54:03
Speaker 1: otherwise my entire life's work is uh, it's just much
54:07
Speaker 1: more theoretical than I ever imagined. But thanks very much
54:10
Speaker 1: for joining us on the podcast today and for thinking
54:12
Speaker 1: about these crazy questions and allowing me to talk about
54:15
Speaker 1: aliens and philosophy at the same time. I really appreciate
54:18
Speaker 1: you coming on the podcast. All right, Thanks Daniel, thanks
54:20
Speaker 1: for having me, Thanks for listening, and remember that Daniel
54:31
Speaker 1: and Jorge explained. The Universe is a production of I
54:33
Speaker 1: heart Radio. For more podcast for my heart Radio, visit
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54:40
Speaker 1: listen to your favorite shows.