Making Sense with Sam Harris - #124 — In Search of Reality

Episode Date: April 21, 2018

Sam Harris speaks with Sean Carroll about our understanding of reality. They discuss consciousness, the many worlds view of quantum mechanics, the arrow of time, free will, facts and values, and other topics. If the Making Sense podcast logo in your player is BLACK, you can SUBSCRIBE to gain access to all full-length episodes at samharris.org/subscribe.

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So this is my event with Sean Carroll, the physicist from Caltech, that we recorded in Portland. And as you might expect, we range over many topics, both of scientific interest and topics about which we disagree. And people seem to like it in the room. And I hope you like it wherever you are. And now without further delay, I bring you Sean Carroll. So I'm going to jump right into this because we have a great guest. My guest tonight is a theoretical physicist from Caltech. He has a PhD from Harvard. He has worked on the foundations of quantum mechanics. For some time, he's focused on the emergence of complexity

and the arrow of time. He's been awarded prizes of many sorts from NASA and the National Science Foundation, the Sloan Foundation, many other societies. He is also a consultant for film and television and he has written a fascinating book which unfortunately is not for sale here but I highly recommend you get it. It's called The Big Picture on the Origins of Life, Meaning and the Universe Itself. Please

welcome Sean Carroll. Well, Sean, thanks for doing this. Thanks for coming out. Can I just say, these are the most comfortable seats I've ever sat in on a stage. Like every time I see pictures of you at the podcast, you have these wonderful wonderful overstuffed do you have a hookup or something I have very little control over what chairs actually arrived very well okay but it seems to work out at least in this universe I don't know if you've been following along low Lo, these many years, but Sean and I have had a slightly prickly relationship online and we've had disagreements in the past

that I really would like to work through here. So this is more than the usual podcast. This is an experiment in conversation. And there's so much we agree about, so much we agree about in terms of just the importance of getting our hands around a realistic picture of what's going on in the world and using science as the basis for that conversation. But there are places where I think we have probably been talking past one another. And so I want us to sneak up on our differences.

And I want to use your book as the template for that. Again, your book is a fascinating look at, as advertised, the big picture. Let's start with this notion of what you call poetic naturalism. How do you frame your worldview? Sure. So poetic naturalism, there's two words. Naturalism is just the idea that there's only one world, the natural world, the world that we learn about by doing science, the world that obeys rules and does its thing. So in other words, it's kind of defined in opposition to whatever might be not naturalism. If you believe that there were extra spirits or a realm of divinity or anything like that, that would not be naturalism. So naturalism is close to atheism in a sense, but rather than just saying there is something you could imagine called

God and that God doesn't exist, it's a positive statement about what does exist, the natural world that we can study using science. And then the poetic is the idea that there are many ways of talking about that natural world, which both means that there are different scientific ways, we can analyze it at the most comprehensive fundamental level of particle physics, talking about that natural world, which both means that there are different scientific ways. We can analyze it at the most comprehensive fundamental level of particle physics and general relativity and so forth. There are more emergent levels that are still nevertheless scientific and descriptive, biology all the way up to sociology or psychology. And then there are levels where we might actually get more poetic, which involve aesthetics or judgments or values, where I would argue the descriptions are not fixed by the facts of the universe themselves. I think the difference between us, if there

is one in the end, is in what we will ascribe to the poetic side of that dichotomy. Right. We're both naturalists. That's right. to the poetic side of that dichotomy. Right, we're both naturalists, that's right. Yeah, it's either naturalist or not to talk about values and meaning and the good life. And again, let's creep up on that. So you certainly are a fan of the concept of the unity of knowledge.

You don't think that there's a disjunction between levels. So if we're talking about physics, everything above that as an emergent property is beholden to that as its micro constituents. And it doesn't make sense to talk about cocktail parties and stock markets in terms of atoms merely, but at some level, reductionism runs through. Yes. I mean, certainly at the level of scientific description of what happens in the universe. The big thing that I try to push in the book is that there are these higher levels of emergent descriptions, but they better be compatible

with the lower levels. And in particular, I'm not a fan of what even some of my scientific colleagues call downward causation. the idea that somehow the shape of a macroscopic thing or the purpose of a macroscopic thing can feed back and change the behavior at the microscopic level in a way that you wouldn't have known about if you were just doing the microscopic level. I think that it really is reductionistic in that sense. In principle, we can build up. Now, in practice, when we do biology or chemistry or psychology, there is a non-reductionist element in the sense that as a practical matter, the way to learn new things about biology is not to think about particle physics. Right. We can discover regularities at the higher levels that we don't need to know about what's going on at the lower levels to discover them.

But they still better be compatible with them. Right. So let's revisit that notion of downward causation, because it has never made sense to me either. So the idea is that you have emergent properties like minds and consciousness, or just the macro level, as you say, shape of objects, right? So you have collections of atoms that at some higher level have, you know, even temperature is an emergent property. I mean, one atom doesn't have a temperature, but you get collections together,

and then their motion is described as temperature. But this notion that a higher level phenomenon can then, by virtue of its existing at the higher level, come down and have causal properties with respect to the lower level. How is it that people are endorsing that idea? Because we have scientists who are talking in those terms. You've come to the wrong place. It's one of those ideas I've tried to understand. There's a lot of smart people who believe this is a very important part of how we describe nature. I've never even been able to understand what they're saying, really, I think. You know, well enough, you would like to understand something well enough to be able to give a good defense of it yourself before you said it was wrong, which I don't think I can do.

But the example on the level of basic physics that is sometimes given is the formation of snowflakes. You know, snowflakes have this six-fold symmetry, and they're all different, and they have this beautiful pattern. And people say, you know, at some level, it's water molecules sticking together. But to understand what any one individual water molecule is doing, you need to understand the whole shape of the snowflake. But if that's the example, it's just manifestly wrong.

Like if you really knew what every water molecule was doing, that's all you would need to know. There's the famous thought experiment of Laplace's demon. Pierre-Simon Laplace back in circa the year 1800 said, if there were a vast intelligence that knew literally everything about the universe, the position, the velocity of every particle of matter in the cosmos, and knew all laws of physics and had infinite computing power, that intelligence could predict the future and retrodict the past with perfect accuracy. So that's what we're imagining when we pretend to be fundamental physicists. If we were Laplace's demon, would you need to know that the water molecule was part of a snowflake?

I would say no. But of course, the hidden agenda there is they want to use it to talk about consciousness. They want to say that somehow the fact that we are conscious changes how even our cells or atoms behave in a way that we wouldn't have guessed from reductionistic principles, and I just don't agree with that. Yeah, well, the problem there is, and this is a genuine mystery as to why consciousness would have evolved if it's an evolved property of creatures like ourselves, is that if consciousness is just arising by virtue of some micro-constituent phenomenon, so some level of information processing, in our case, neurophysiology,

if it is effective, if consciousness is doing something, if there are certain mental operations that can't be done but for the fact that there's something that it's like to be doing those things, it still must be effective by virtue of its micro level properties at the level of the brain. I mean, it is neurons affecting neurons and their future states. Otherwise, you're talking about some magical influence. Well, that's right. And so there's a tension here, right? There's a tension between on the part of many people, there's a reluctance to think that what it is like to be something, the hard problem of consciousness, can be explained simply as an emergent phenomena

on the basis of what our atoms and molecules are doing. But at the same time, there are subsets of these people who are very much in favor of science and know that the atoms and molecules are doing something and they have their own laws of physics. So they're forced ultimately to panpsychism, to the idea that there is not just a physical property of every particle of matter in the universe, but there are mental properties as well. And the mental properties aren't very efficacious in doing anything when it's just an atom or two, but when it comes together to make a whole person,

then the mental properties come together to give us consciousness. Just saying it out loud makes me think, how could anyone ever believe that? But it is a surprisingly popular position in some circles. I'm probably not doing it justice. Well, but it's also hard to see how the universe would be different if that were so. I mean, I wouldn't expect this comfy chair to behave differently than it's behaving if there was something that it was like to be an electron, say. I mean, if electrons buzz with some interior dimension of subjectivity,

it's not like they're thinking thoughts or forming behavioral plans or feeling themselves to be in relationship. Yeah, I mean, to be as fair as I can, it's not very conscious, the chair. It's just a little bit conscious. That's even, you know, an electron, David Chalmers will say, is maybe a little bit conscious. Right. And I think, you know, and it gets into, I don't know how much you want to discuss it, but then, of course, there's the famous philosophical zombie thought experiment. Can you imagine something that acts like a person but has no inner sensations,

does not know what it is like to be a person, but acts exactly like a person would act? And to me, the answer is no, that's not even conceivable. Because if you asked a zombie, what are you feeling right now? It would say it's feeling something because otherwise it would be acting differently, right? So why is the zombie lying to you all the time about feeling something inside? How do you know you're not a zombie yourself? So I actually just don't think that's possible. And I think that ultimately the attempts to wriggle around basing reality in stuff obeying the laws of physics don't quite hold together. Yeah. Well, I think you and I are on the same page as far as consciousness still being fundamentally mysterious.

Depends on how you're leading the word mysterious there. Well, it's just like we haven't, we don't know at what level it arises in the physics of things. Sure. My message throughout the book and more broadly is, you know, the subtitle of my book is on the nature of life, meaning, and the universe itself. And even though we're not selling the books here, you can still buy them on Amazon from your phone right now. But if you do, you will not learn the origin of life, the origin of the universe, or the meaning of life. The point is that I argue that we can talk about these things in the framework given to us by naturalism. I don't give you the answers. The answers are still things we're looking for. That's how science works. I think they will someday be found. And I think there will ultimately be a naturalistic, physicalistic grounding for whatever it is we find them. In other words, there's no reason on

the basis of what we currently know about the universe to put large credence in the idea that there's something beyond the physical world. How do you think about possibility as a physicist? So we live in a world where certain things happen and certain things which we can imagine happening, which seem compatible with the way things might have happened, don't seem to happen. If your answer to this is some many worlds version of QM that we're every, yeah, so that I'm interested in that but how do you map this claim that something might have happened but didn't happen onto naturalism as a physicist well i think that there's yeah there's two levels to that as it were um there is we could go into again at whatever level detail you want to the many worlds version of quantum mechanics which is the one that i think

is probably right we don't know for sure. And in that version, when you specifically have a quantum mechanical measurement performed, so you have some quantum mechanical system, some other system that interacts with it, obeying the laws of physics, becomes entangled, and that's what we call a measurement. The universe, as it is described by the quantum state, branches into multiple possible, but equally real, different universes, one in which the spin was up, one in which the spin was down. I have an app on my iPhone that will do this, that will actually branch the wave function of the universe. Divide our universe? Yes. So if you don't know what to do, if you're like, should I have Chinese food for dinner? Should I have pizza? Shatter the universe? Yes. So if you don't know what to do, if you're like, should I have Chinese food

for dinner? Should I have pizza? Shatter the universe? You can have one universe each, right? So that doesn't mean that everything happens. It means that everything that is compatible with the laws of quantum mechanics happens with some non-zero probability, okay? So it is a feature of the world that there were relatively few branches of the wave function of the universe in the past, and there are relatively more in the future. So possibilities proliferate as time goes on. Now, there's also an entirely different discussion about the emergent levels of description, which are not comprehensive, where in some sense you're ignoring certain facts that are true about the universe. When we discuss the air in this room as a fluid with a temperature, a pressure, etc., we can make enormously successful predictions about how the

air in this room will behave just on the basis of its fluid properties. And that's kind of miraculous because the total information about the air would be what Laplace's demon would have, right? The position and the velocity of every single molecule as well as its rotation and so forth. And miraculously, we don't need that information. We can do with much less information and still make wonderfully precise predictions, but not perfectly precise

predictions. So because of that missing information, there's another sense of possibility that comes in, just the possibility based on ignorance, that you make predictions on the basis of incomplete data, they're going to be probabilistic ones, not deterministic ones. But when you're talking about something that happens or not, but when you're talking about something that that happens or not what sense can be made of the claim that something else might have happened in that case in the in the many worlds version everything that can happen is happening yes right so so in some sense there is only the actual it's most of it's not in this universe but but it's still happening so there was some possibility that i might have picked this up and put it down

and then picked it up again and put it down and did that 75 times to the consternation of everyone in the room. Hopefully the probability is low, but yes. But if there's a non-zero possibility of that, that happened somewhere. Yes, that's right. And every other conceivable adumbration of that. So I was singing

the Star-Spangled Banner at one point when I was doing that. It gets worse than that, yeah, but yes. I go, well, if you've heard me sing, you know it doesn't get much worse than that. Maybe it doesn't get worse. But this is supposed to be science, right? But this sounds like the strangest

and least believable idea on offer. How is it that science, after centuries of being apparently rigorous and parsimonious and hard-headed, finally disgorges a picture of reality which seems to be the least believable thing anyone's ever thought of? You've come to the right place.. You've come to the right place. You've all come to the right place. So let me just remember that there's this entirely different notion of possibility that we should get to, which is what could have happened given what we know, given that what we know wasn't everything. What we're talking about here with the many worlds interpretation is we know everything.

Let's let us know everything. Let us know the complete quantum state of the universe. And if you believe this story, then there's these multiple branchings and everything that had a non-zero chance of happening actually does come true just in different universes for all intents and purposes. And if I can rephrase the question you're asking, why in the world would anyone believe that, right? So the answer is that it is the simplest, purest, most parsimonious way of making sense of the data. And to bolster that claim, to sort of see why you would get there, you have to know just a little bit about quantum mechanics. So think about what quantum mechanics says is that there's a difference between what is, how we talk about the world, how we, you know, attach mathematically rigorous quantifications of the state of the world to actualities, versus what the world looks like when we look at it. Okay?

And looking at it isn't anything weird about consciousness or human brain or anything like that. A video camera or a rock can look at things just as well. So that's just any version of quantum mechanics. Any version of quantum mechanics says we describe the world differently when we are and are not looking at it. So how do you make the most parsimonious sense of that? We say that if you have an electron, for example, a little particle that is spinning, and if you measure it, whether

it's spinning, given some axis, is it spinning clockwise or counterclockwise? So it's the only possibility. It's one of the wonderful simplifications of quantum mechanics. It's never in between. If you measure it a certain way, it's clockwise or counterclockwise, that's it. Various reasons why, which we could go into, convince's clockwise or counterclockwise, that's it. Various reasons why, which we could go into, convince us that when we're not looking at it, the right way to talk about the electron is as a superposition of spinning clockwise and spinning counterclockwise. So it's not that we don't know, it's that it's in some sense doing both with sort of different amounts of admixture clockwise and counterclockwise.

And then when you look at it, you only ever see it do one or the other. OK, so the question is, what happened when we looked at it to make it go away? Well, we have an equation, right, the Schrodinger equation, which tells us what happened. And what the equation tells us is that before you looked at it, there was an electron that was in some mixture of clockwise and counterclockwise, and there was you, and you hadn't looked at it yet. And after you looked at it, there were two things. There was the electron was spinning clockwise, and you saw it spinning clockwise. And there was the electron was spinning counterclockwise, and you saw it spinning counterclockwise And there was the electron was spinning counterclockwise,

and you saw it spinning counterclockwise. That is the straightforward, unambiguous result of the equation. The question is, what do you do about that? And from 1920s to the 1950s, the answer was you panic. And you say, well, I only saw it spin counterclockwise or clockwise, so the other possibility magically disappears. And this is called the Copenhagen interpretation of quantum mechanics, and I'm being very unfair to it, but we're among friends. So it was in 1957 that a smart graduate student named Hugh Everett said, I have a better idea. Rather than magically getting rid of it, let's just admit that it's there, because that's what the equation says. What would be wrong with that? And people say, well,

we only see one or the other. And Everett said, yeah, but now there's two of you. There's one that saw one and one that saw the other one. And they kicked him out of the field. He left physics entirely because they wouldn't talk to him anymore. But this is the birth of what we call the many worlds interpretation. In this universe, they kicked him out. In this universe, we kicked him out. Yeah, he's the king of physics and some other branch of the wave function. But the point is that it is in terms of ideas and mathematical concepts, you cannot get simpler and more parsimonious than the many worlds interpretation. In terms of universes, it's messy, but how should we judge it? I would go on the basis of concepts,

not on the basis of universes. Right. And then what has that, so I want to bring in this notion of time because you've focused on the arrow of time and why time seems to be as strange a phenomenon as it is. But there's this notion of a block universe that you don't hear much about now, which is the notion that the future and the past equally exist in some kind of atemporal space. It's like we're all living in a novel and we're living on page 45 now,

but page 95 exists just as much as the page we're on and could be visited, presumably. Just wait. Exactly, yeah. Is the block universe a retired concept, or are we still thinking in terms of a block universe? No, it's a conventional wisdom. It is, okay. But taken as a block, there is no such thing as process or an event or causality isn't it there's just this overarching

pattern that is the block right well there are events there are events scattered through the block um it's a different way of thinking it's counterintuitive i mean it's like a giant noun rather than a giant verb if you think of in terms of time and events and process, you're thinking in terms of a verb. Verbs are relative. And this is actually, it's closely related. Everett's PhD thesis was called the relative state version of quantum mechanics for kind of this kind of reason. You know, now is just a way of talking about my relationship to other moments of time that are equally real. They don't exist now, but they exist in the sort of whole four-dimensional block version universe of reality. And the only reason to do this is because, again, it's the simplest, most straightforward reading of the equations. The equations that we,

as far as we best know them right now, of fundamental physics, don't distinguish between yesterday, today, and tomorrow. They're just different numbers on a line. And both the block universe view and the many worlds view come from this philosophy that, you know, you mentioned before, you sort of gave the game away, that these pictures are very counterintuitive. And the philosophy is, well, sure, they're counterintuitive. Like, why should our intuitions, developed over some number of years of evolutionary time, teach us anything at all about relativity, cosmology, or quantum mechanics? Like, it would be very surprising

if our best view of the fundamental nature of reality was not highly, highly counterintuitive. And in that situation, I would argue, the best thing we can do is take the equations seriously. And that leads us to the block universe and to many worlds. Okay. So then why does time seem to flow the way it does? And how do you think about the future being different from the past? Yeah. So that's a good question.

We don't know the entire answer to that. Yeah, so that's a good question. We don't know the entire answer to that. Half of the answer is the physical answer as to why the past seems different from the future is because of entropy, right? Entropy is physicists' way of talking about the messiness, the disorderliness, the disorganization of a physical system. And entropy tends to increase in closed systems over time. So if you take cream and coffee, mix them together, they become higher entropy as time goes on. It's very easy to mix them together. It's very hard to unmix them. If you have cream mixed in with coffee, it'd be very, very difficult to lower their entropy. It can be done, but only by increasing the entropy of the universe

somewhere else. So the amazing thing is that this simple, definite feature of the universe, which is enshrined in the second law of thermodynamics, entropy increases, we would claim that underlies every single difference that we notice between the past and future. So the fact that we were born as little babies and will die as older people, the fact that we remember what happened little babies and will die as older people, the fact that we remember what happened yesterday but do not remember tomorrow, the fact that we have free will about making choices today that can affect what happens tomorrow, the way that I put it sometimes is you all could choose right now to get up and leave, right? That is something you could do

because in some sense to you, the future is open. You could not choose to not have come here already. Where does that asymmetry come from? There's a long song and dance, but ultimately the answer is because entropy was lower in the past. How that works psychologically is more of a neuroscience problem, actually, than a physics problem. We carry around in our brain little memories of what just happened, as well as little projections of what will happen. And we're constantly updating these on the basis of new information. And that gives us this sense of an impulse or a flow, even though to a physicist, all of those moments of time are equally real. Right. Well, so you mentioned free will, which is getting us closer to areas of interest and potential disagreement. Although I don't think we...

Have you thought about that? Yes, a little bit. But I actually don't think we disagree about the core claim, which is the free will that most people think they have, this notion that you could have done otherwise. Neither of us believe in that. There's the physics of things. If you could rewind the universe to precisely the state it was in when everyone decided to come here, everyone would still decide to come here helplessly a trillion times in a row, for better or worse. Yeah, they might be rethinking it now. I would put a little footnote because whenever you say

could not have been different, you have to say given what. So if you were Laplace's demon, if you were, like you correctly said, if you absolutely knew everything about the physical state of the universe, then it would have,

given the uncertainties due to quantum mechanics, for putting that aside for a second. But otherwise, yes, it would have, according uncertainties due to quantum mechanics for putting that aside for a second. But otherwise, yes, it would have, according to the laws of physics, played out in exactly the same way. But as we footnoted before, there are other ways of describing the universe, emergent higher-level ways where you're not Laplace's demon. Where you can say, given what we actually know about the physical situation at some earlier time, what could have happened. And there you still might get some probability distribution over what could have happened, and the answers might have been different. Well, so you're saying that it's a lack of

information that carves out of space for free will? Yeah, absolutely. So, but it's that a puppet is free as long as it can't see its strings? What would it mean to actually see the proximate cause of the thing that is effective in each moment? Well, I think that it would mean that you would have to be Laplace's demon, that you would really have to. So the idea of these emergent theories is you throw away a lot of the information that Laplace's demon would have, yet you still retain some of the predictive power. And in fact, like I really like to emphasize, this is a very unusual, special, quasi-magical situation when that happens.

Typically in physics, if you give me some information about the air in this room, right, if you give me the position and velocity of every molecule of air, and you pick out one molecule and say, how is it going to move, right? So Laplace's demon has no trouble telling you exactly what it's going to do. But if then you say, okay, I only tell you the position and velocity of half of the air molecules, Laplace's demon has no idea where this one's going to go, because it's going to be hit by ones you don't know about. That's the generic case in physics. You throw away a little bit of the data, you lose all predictive power. Emergence is this wonderful exception to that rule where you throw away almost all of the data and keep an amazing amount of predictive power. So if you want to talk about the motion of the earth around the sun, you don't need to talk about the position and velocity of every atom in the earth, right? You just need to know the center of mass. And that is an enormous saving of information

and you still get quite good predictive power. So when it comes to things like human beings, the best emergent theory that we have necessarily has probabilities built into it. We don't have a deterministic way of talking about human beings given the information we have about them. That's why I would argue it's useful to talk about free will. Well, the thing is, but adding probability to it or chance or randomness doesn't give people the freedom they think they have either. doesn't give people the freedom they think they have either. So if I told you that you might have done differently had someone rolled a dice in your head and it would have produced a different synaptic outcome,

that's not what people feel they have as the authors of their actions. So the libertarian sense is there's no upstream proximate cause of my decision but for me making the decision. The fact that it gets made by a deterministic universe or deterministic universe plus probabilities that I didn't have a hand in either, that isn't the feeling that gets carried forward in consciousness in each moment. Yeah. So I don't want to get too bogged down in this because this is the sort of the definitional morass that becomes less interesting. So I think people think different

things about what they have in terms of free will. Neither one of us believes in libertarian free will in any possible sense. If you were Laplace's demon, you would be determined 100 percent. The way that I like to put it is if you didn't believe that, if you believe that even if we knew everything about your atoms and molecules, there's still something extra that makes me able to affect my motions over and above that, then here's a simple experiment. Jump out of the window of a tall building and use your free will to change the motion of your center of mass. No one thinks they can do that, right? They think they can use their libertarian free will to change their hands,

but not their center of mass. But the truth is you don't even have to engage any kind of suicidal experiment like that. I invite you all to just try not to hear the sound of my voice right now. Use your free will not to hear me say these words. Use your free will not to hear me say these words. Use your free will not to understand them. You know, like you speak English. You're helplessly decoding the meaning of these sounds. There's not a person in this room who can stop doing this right now.

Right. So if your freedom doesn't extend to even that. Sure. That's right. Happily, no one has taken me up on the dare that I have suggested to them. But there are other aspects to free will. And this is why I don't even like using the term free will. As a compatibilist, I'm sort of regretful that free will is the label that has been given to the thing we argue about. Because neither you nor I nor Daniel Dennett or any of our friends at this level think that there is some magical spark that lets us overcome the law of physics, right?

The question to me is, what is the best possible way we have of describing how human beings behave? That's the question. As far as I can tell, the best emergent effective theory we have of human beings is one that inevitably involves them being agents that make choices. Certainly, I think, and we can argue about this too, if we want to discuss things in a vocabulary of morals and oughts and responsibilities, we need to imagine that human beings make choices. And also empirically, I think that when I go to the restaurant, I do make choices. So if someday we come up with a better description, a description of human beings that given the same data we have about them, lets us describe what they will do with better accuracy,

then I will totally give up on any connection or commitment I have to the idea of free will. I just don't see that theory yet. Practically speaking, it's not that the best way to order food in a restaurant will be to scan your brain to figure out what you're going to order. The easier thing is just to order. But the order still comes from somewhere, which we know that if we were paying attention to what's happening at the level of the brain, it is happening there and is determining the choice you make even while you still think you're making up your mind, the you, the conscious witness of your experience. And we know that's the case. And that is undermining of what people feel they have. And the reason why I think this is important and not just a merely academic conversation is that I think this does begin to have ethical implications when you think about the possibility of just understanding the human mind more and more deeply.

So we have this category of human misbehavior that we call evil now. So there's evil people in the world. They do terrible things that we have to figure out some way to prevent. things that we have to figure out some way to prevent. But the physicist in you must see them, I presume, on some level as malfunctioning robots, right? I mean, they're part of this concatenation of events that's ultimately describable in terms of physics. And if there was some way of understanding evil at the level of the brain, there would be a more complete description of it there. And if there were a way to remedy it, right, if there were a cure for evil, if there were a pill that could cure a psychopathy, say, I mean, just take one

band on the spectrum of evil. So we have these people who we diagnose with psychopathy. And that's, we sort of dimly understand anomalies in the brain that correlate with that condition, conditions of low empathy and all the rest and a disposition to use instrumental violence. If we understood that perfectly and could intrude in the brain in a way that was harmless and just change them. And so every time you gave a psychopath this pill, he promptly apologized for everything he had done and said, I just, I'm such a relief. I was such a bad person and now I'm just horrified and thank you for this cure. And then he lived every day of his life as morally healthy as any normal person. We would

cease to have this category of evil. We would just cure people. And so we certainly wouldn't have a retributive justice system that punished people because they were the true deserving authors of their actions who deserved to suffer for all that they had done. On some level, we would recognize them to be casualties of bad biology, which we now have a remedy for. Short of getting that remedy, the door is already open to viewing even evil people as, on some basic level, unlucky inheritors of bad biology or a bad mixture of biology and environment or just whatever concatenation of causes makes them how they are. Yeah. So, I mean, there's a lot going on there. I think that I completely agree that thinking clearly and scientifically about where people's motivations and the causality behind their actions come from will have enormous repercussions for how we think about responsibility, how we do criminal justice, how we do morals and ethics more generally, right? And I think that advances in neuroscience and

psychotherapy of various ways or alterations to the brain could very well have these enormous ethical implications, which I don't have strong feelings about what they are, but I totally agree that we should start thinking about them, and that's very important. I don't really think that it gets at the point that I wanted to make about how we think about the effective theory of human beings as emergent phenomena. I think that if you imagine, I think that what you're doing by imagining looking into the brain and seeing what someone is going to do and saying that changes our understanding of their responsibility for their own actions, to me, that's fine. But you're not changing our best theory of human beings. You just have a theory of a lower level.

You know, Plato would have said that there is something called the platonic form of a chair, and this chair participates in that form. And today, we know that's not true. The chair is made of atoms, okay? It's a particular shape of atoms. But we don't say, therefore, there is not a chair, right? Therefore, the chair went away. There's a description of the chair as a chair, the level that we describe it as chairs, and there's another level below where we describe it as a collection of atoms. I see no incompatibility with saying that there is a way of describing human beings, which is the best way we have given the data and information we have about human beings in our everyday lives, which describes them as agents capable of making choices,

and also that if we knew more about the microprocesses in their brain, we would use a different vocabulary for describing what they do. You don't see an ethical implication to the recognition that if you were exactly in the place of the person who's behaving badly, you would be that person behaving badly. So you're lucky not to be Saddam Hussein or some bad person. If you had his brain and his life circumstance, you would be precisely that person. There are no degrees of freedom, apart from whatever randomness you want to throw into the system,

to avoid being that person. Yeah, I think that those sentences literally do not make sense. The sentence is, if I were Saddam Hussein. I understand that something gets lost there because there's no you carried over. Exactly. I think that kind of matters in this case. Do you feel you can take credit for being who you are?

Part of it. What part? You know, I decided to get a PhD. You did? I did. You did. And but can you explain? You did too. Well, no, because see, this is the problem I have in these conversations, because my experience is actually compatible with what we're calling determinism or determinism plus randomness. So like I, when I look at how decisions get made, I experience a fundamental mystery in each moment around just what becomes effective. So the decision to, you know, I see a list of topics here that I can choose, right? Now, if I skip over one and go to the next one,

that, quote, decision is always mysterious on some level. It's like I can have some story, post-hoc story about why I did it in that case, but that always strikes me as post-hoc. And even if the story is accurate, even if I said, oh, we don't need to talk about that because I talked about that on my last podcast, the fact that that memory arose in that moment is mysterious. The fact that it was effective in the way that it was is mysterious. The fact that it didn't have the opposite effect is mysterious. I could have said, oh, well, I talked about that in my last podcast, but Sean's the perfect person for me to bounce that off of. So everything there is compatible with determinism. So in this case, I do actually feel like it's possible to see the strings. Then the puppetry is no longer an

affront to our subjectivity. It's just, it actually is bringing our subjectivity more in line with what we have every reason to believe that data are. Right. So the way I would disagree with this analysis, I think that what you're saying is related, although at the end of the day, different to an argument that John Searle gave in favor of free will. The argument, it was just a joke. He was supposed to be a joke. And he said, look, if I really didn't believe in free will will when I went to a restaurant and the waiter says, what would you like to eat? All I should ever say is just give me whatever the laws of physics determined I will have. Right. And of course, no one does that.

And Searle concludes from that we must have free will because, you know, we don't really act like that. But I think that that's a misunderstanding in the sense that it's a mixing of levels. I think that the tension that you're pointing at comes from, on the one hand, we have this way of talking about human beings as agents making choices. At the other hand, we also have a different, slightly lower level description of brains. And there are different parts of the brain and they're talking to each other and there are subconscious things going on. And we have histories that, you know, led us to certain places that we didn't control. And all that is also true. But it's compatible in my mind with the existence of another layer where we can talk about human beings as people making choices.

It's just that it's a different way of talking about the same stuff. It's not incompatible ways. Yeah. So I fully agree that we can talk in a conventional sense about choices and the proximate cause of doing something is rather often choosing to do that thing. But if you actually drill down on what a choice is, you are once again laid bare to this stream of causes, which you, the witness of each conscious moment, haven't authored. Well, right up until that last clause, I was going to totally agree and say we should declare victory. But I think that up until that last clause, I thought the thing that you were laying out, that there are two different ways of talking about human beings.

Well, I guess my question is, do you feel that your experience is compatible? Let's just say that determinism is true and provably so, so that we could have the people with the right scanners backstage actually anticipating everything we're going to say before we say it. So we could just see a printout of everything we said here before it could possibly have been recorded, say, or some way of proving to us that we are mere puppets. Is your conscious experience compatible with that fact or not? Okay, so that's not an affront. The fact that everything you said tonight could have been

predicted is fine. That maps onto your experience. It could have been predicted by the imaginary Laplace's demon in the back room. It couldn't have been predicted by me. Yes. And I think it was Max Planck who had that construal of free will. That it's basically, it's not a claim about the physics of things. It's a claim about the psychology of being a person. The fact that you have incomplete information about what you are going to do always makes it seem like you are the free author of your thoughts and actions. It's a psychological claim about what it's like to

have incomplete information about your own physics. Well, we're getting very, very narrow here, but it's not quite, to me, a psychological claim. It is, again, a claim about what is the best way of talking about human beings at this level of description. And the way that it sounds wrong is when you use words that should only be used in the vocabulary of human beings making choices like you or yourself, and you translate them down into the layer that is more imaginary, where we have a lot more data, where you say, you are the author of all these influences, or how could you be affecting all these things that you didn't even know were happening? But you're not allowed to talk that way. You're allowed to talk about you as a person talking to other people making choices, or you're

allowed to talk about brains being influenced by things, but not both at the same time. And you don't see a way in which those two levels will come into tension when we have a greater understanding and more predictive power of the base level. I mean, it is just a thought experiment to think of Laplace's demon backstage, but more and more.

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