71 | Philip Goff on Consciousness Everywhere

0:00:00 Sean Carroll: Hello, everyone, and welcome to the Mindscape podcast, I'm your host, Sean Carroll. And today we're going to go back into consciousness, not just the easy problem of consciousness, how the brain looks at the world and figures out what is where and how to respond to it, but the hard problem of consciousness, what makes us who we are, how we experience the world, what it is like to be us, that inner subjective first person view that we have of reality.

0:00:26 SC: Now, if you've been following me for a while you know that I'm a naturalist, I'm a physicalist, in fact, which means I think the world is made of stuff obeying the laws of physics and that's basically it, except when that stuff comes together to form complicated things like human beings there can be new emergent phenomena that arise, and consciousness is one of those, consciousness is just an aspect of the collective action of underlying stuff obeying the laws of physics. But you will not be surprised to learn that there are those who disagree, and those who disagree need not be hardcore Cartesian dualists, they don't necessarily think that there's a disembodied mind that somehow interacts with the body.

0:01:07 SC: It can also be true that you believe the world is made of physical stuff but the physical stuff has extra properties, mental properties, and this point of view drives you in the direction of panpsychism, thinking that everything is a little bit conscious. It's not just that something new happens when atoms and particles come together to form a brain, but there was something that was there all along and it becomes important and noticeable once you get something like an organism or a brain. So for today's guest we have Philip Goff, who's a professor of philosophy at Durham University in the UK and one of the leading thinkers on panpsychism. He is all for it, I am against it so we have a very nice conversation.

0:01:49 SC: Philip is the author of an academic book called Consciousness and Fundamental Reality, and also a brand new just published popular level book called Galileo's Error: Foundations for a New Science of Consciousness. So I have fun in the podcast with the idea that I'm on Galileo's side and Philip is against Galileo side, but basically Philip is also pro Galileo. He thinks that Galileo made a mistake in overly mathematizing the world that we live in, that there's a qualitative aspect to the world as well as a quantitative aspect. So you can listen to what we say back and forth about both sides of this; mostly as usual I give Philip a chance to give his sales pitch for his side, but you can tell where my sympathies lie.

0:02:30 SC: Remember that if you want to support the podcast you can go to the webpage, preposterousuniverse.com/podcast. There you can find transcripts of every episode and audio player and show notes, links to the person we're talking about, their Twitter bio and so forth. You can also find a Patreon link so if you support on Patreon you get the podcast without any ads and you also get a monthly "ask me anything" episode and of course you can go to Apple or iTunes and leave reviews for the podcast, we always like that. And with that, let's go.

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0:03:18 SC: Philip Goff, welcome to the Mindscape podcast.

0:03:21 Philip Goff: Thank you very much, good to be here, thanks for having me.

0:03:24 SC: I'm very excited for this podcast because I think... I'm not completely sure, but I think this is the podcast on which the guest and I disagree most strongly about most of the important things we'll be talking about, but in a productive way. And I really think... I read you have a new book coming out, I read the book and it's a fantastic book, very, very clear statement of the case that you want to make. And that case, of course, is for a panpsychist view of consciousness. So why don't we... We had a... I had a previous interview with David Chalmers and so some of the podcast listeners will have heard, that but not all of them, so let's not assume they know anything. Why don't you tell us why there's a problem with consciousness, what it is that we're trying to figure out when we talk about consciousness?

0:04:07 PG: Sure, well, it's a big discussion but I think the core of the problem is that physical science works with a purely quantitative vocabulary, whereas consciousness is an essentially qualitative phenomenon, just in the sense that it involves qualities, the redness of a red experience, the smell of coffee, the taste of mint. And you can't capture, it seems, these qualities in the purely quantitative vocabulary of physical science, you can't capture in the quantitative language of neuroscience the redness of a red experience. And so it looks like as long as your description of the brain is framed in a purely quantitative vocabulary, it seems that you're going to miss out these qualities of consciousness and thereby miss out an essential component of consciousness. So that's the way I like to frame the starting point of the philosophical problem, this clash between the quantities and qualities, the quantities of physical science and the qualities we know from our own first person conscious experience.

0:05:31 SC: So for people who do know a little bit about the issue, you're interested here in the hard problem of consciousness, that first person subjective experience, less so in the easy problems about how people behave and how we treat them as conscious creatures, how they perceive the world and things like that?

0:05:49 PG: Yeah, I mean, look, there's all sorts of very important things we can do with neuroscience and neuroscience is absolutely essential for making progress on consciousness. I'm a big fan of neuroscience and I try to keep as up to date as I can. But I think essentially... Here's another way of putting you... What neuroscience gives us are correlations between brain activity and conscious experience, so you can scan people's brains, you can ask them what they're thinking and feeling and you can get that rich body of correlation between certain kinds of brain activity and certain kinds of conscious experience. But that in itself is not the full story, because if we want a complete theory of consciousness, if we want, if you like, to move to solving the hard problem, we want to explain those correlations, we want to say, "Why is it? Why is it when you have such and such brain activity you have feeling of hunger or whatever?"

0:06:54 PG: And because of the purely quantitative vocabulary of physical science, it's hard to see how you can provide any such explanation. So, yeah, the starting point is... My starting point is, we know that consciousness is real. Nothing is more evident than the reality of our feelings and experiences, so we have to find some way of integrating it into our scientific story, but we can... And we can build correlations and that's fine and that's important, but to give a kind of deeper explanation, we come up against this difficulty of the essential qualitative nature of consciousness and the quantitative vocabulary of physical science. So, yeah that's the challenge.

0:07:43 SC: Yeah. And just a preview a little bit, I'm sure we'll get into this in more detail, but my point of view, the point of view of someone like me which we'll label the materialist point of view going forward, is that in some very real sense there is literally nothing else to say once you've said what all of the physical stuff in the universe does, right? That what we do when we talk about consciousness or even feelings of experiences and so forth is simply come up with a convenient label for a higher level emergent phenomenon that is ultimately nothing more than physical stuff doing things.

0:08:20 SC: And I think, and this is really where David, I guess, and I talked about this a little bit, but I think this is where our conversation is going to be very, very useful and digging into what exactly is meant by that distinction, like whether it is or it can be a complete explanation just to say what stuff does.

0:08:39 PG: Yeah. And, I think that's a coherent position you just described and I read some of your most recent book and... Yeah, and I was actually to say that I was actually struck at how detailed you go into these contemporary philosophical discussions, 'cause everything is so specialized these days, it's hard to learn about... I'm jealous of people in the 17th century where you kind of know everything. [chuckle] It's hard to...

0:09:08 SC: I know. I'm sure they complained too but you know...

[chuckle]

0:09:11 PG: But, yeah, you put quite a lot of research into the details of these contemporary philosophical discussions and... Yeah, I think that's a coherent position you describe, but I suppose if you're going to defend that view... So, maybe that's why I probably wouldn't set things up in the way Dave Chalmers does. That's been a hugely important influential way of setting things up. But you might think, it's sort of already assuming what it's trying to prove, that neuroscience can just give us the easy problems, then there's this hard problem, whereas you might say, "I don't see why there's another problem." But, so what I would say is, okay, fine, that's a coherent position you've just described and that would solve the problem if it made sense, but I think you then have an extra explanatory obligation, right?

0:10:07 PG: You've got to... I would say, maybe you disagree. I would say that we know from our first person perspective from our immediate awareness of our own feelings and experiences, we know that consciousness has this qualitative nature. It involves these qualities, the redness of red experience and so on. And I think if you're going to be a materialist then you owe us an explanation of how that is accounted for in the terms of physical science, how can you account for those qualities in the purely quantitative language of physical science?

0:10:47 PG: You owe us an explanation, perhaps something like the explanation of the boiling point of water we can give in terms of chemistry. So, I think there's at least an explanatory obligation there for the materialist before we can say, "Okay, that makes sense."

0:11:05 SC: Yeah, I think that's perfectly fair and I'm biting my tongue because I want to try to give such an explanation, but I will get it later or, at least we'll talk about it later in the podcast. Let's build our way up. I just wanted to preview for the audience what the stakes were a little bit. You blame Galileo for people like me. This is a very bold move in the book, Galileo is not one of the people who we regularly bash in pop sci discussion. So, maybe give the audience a clue as to what your beef is with Galileo.

0:11:36 PG: Sure. Well, look I'm a big fan of Galileo here as well, I'm being a little bit provocative.

0:11:43 PG: By the way, I was just in Florence in Italy and I don't know if you've ever been there but there is a Galileo Museum where they keep his middle finger... The bones of his middle finger as almost like a religious relic. So...

0:11:56 PG: That's fantastic. Did you go and pay respect?

0:12:00 SC: I did, I did. Yeah, there was no burning of incense or lighting of candles or anything like that, but I did have Alice Dreger as a podcast guest earlier and she wrote a whole book called Galileo's Middle Finger, imagining that Galileo was giving the middle finger to the rest of the world. I don't think that gesture has the same meaning in Italy as it does here, but... Anyway, yes we don't actually want to worship Galileo or anybody else. So, go ahead.

0:12:22 PG: So, what's the issue with Galileo... So, a key moment in the scientific revolution is Galileo's declaration that mathematics is to be the language of the new science. So, the new science is to have a purely quantitative vocabulary. And so, this is a much discussed moment, but what is less focused on, and what I focus on in my book, is the philosophical work Galileo had to do to get to that stage, because before Galileo, people thought the physical world was filled with qualities.

0:13:00 PG: So, there were colors on the surfaces of objects, smells floating through the air, tastes inside food, and this was a challenge for Galileo's aspiration to give a completely mathematical description of the physical world because as we've already discussed it's hard to see how you can capture those kind of qualities in a purely quantitative language. How can you capture in an equation the spiciness of paprika? So, Galileo got around this by proposing a radically new philosophical theory of reality and according to this theory those qualities aren't really out there in the physical world, rather they're in the consciousness of the observer, which crucially Galileo took to be outside of the domain of science.

0:13:55 PG: So the redness isn't really on the surface of the tomato. It's in the consciousness of the person receiving the tomato, or the spiciness isn't really inside the paprika, it's in the consciousness of the person eating it. So, Galileo as it were stripped the world of its qualities and after he'd done that, all that remained were the purely quantitative features of matter, size, shape, location, motion, things that can be captured in mathematical geometry.

0:14:32 PG: So there is this radical division, radical dualism in Galileo's picture between the physical world with its purely quantitative properties, which is the domain of science, and consciousness with its qualities, which is outside of the domain of science. So this is the start of mathematical physics, which has obviously gone very well. But crucially Galileo at least only intended it to be a partial description of reality, right? The whole project was premised on setting consciousness outside of the domain of science. So I think this is really important because... So it's generally accepted now that consciousness does pose a serious scientific problem, which is not always the case. But a lot of people have this following reaction. They say, "Okay, there's a serious problem but we just need to do more neuroscience and we'll sort it out." And I think the reason they think that is because they look at the great successes of physical science in explaining more and more of our universe and they think, "Of course, one day is it's going to crack consciousness."

0:15:38 PG: But the irony is I would argue that physical science has been so successful precisely because it was designed to ignore consciousness. That was the whole set up. So I think if Galileo would time travel to the present day and hear about this hard problem of explaining consciousness in terms of physical science he'd say, "Of course you can't do that. I designed physical science to deal with qualities not quantity." Sorry, other way around, "I designed physical science to deal with quantities not qualities." So this is... What I'm trying to push here, and we're not really at the stage of arguments. It's a sort of narrative that I think... As a philosopher I spend a lot of time on these fiddly arguments, and I think they're important, and maybe we can have some of those. But I think really at the end of the day it's the big picture that grabs people.

0:16:27 PG: The big picture such as you present in your book that, look, the success of science, physical science in particular, of course it's going to explain consciousness one day. But I think actually there's a different way of looking at the history of science such that that conclusion does not obviously follow. In fact, we're probably led in something of the opposite direction. So that's the main...

0:16:48 SC: Just so people know in fact... Yeah, your book is entitled Galileo's Error: Foundations for a New Science of Consciousness. So I'm happy to take the pro-Galileo point of view for the rest of the podcast while you take on the plucky underdog there.

0:17:03 PG: Well, hold on. You should be a dualist if you're going to take the pro-Galileo position. Galileo's position. [chuckle]

0:17:10 SC: No, I'm just, I think that I am what Galileo would have evolved into. That's my goal. Obviously, Galileo lived a long time ago, and I don't really think... This is jumping ahead once again, but I don't really think that it's putting consciousness aside. I think that it is understanding these quantitative features of the world as ways of talking about the qualitative features of the world. That's how I would put it, but first...

0:17:35 PG: If I can just...

0:17:36 SC: Sure, please.

0:17:36 PG: I am inclined to think I am what Galileo would have evolved into, because I think Galileo took physical science very seriously, but he also took the qualitative reality of consciousness very seriously. And I think what we'll eventually get to is a way of bringing both together, and so... Yeah, anyway.

0:17:58 SC: From what I know that Galileo's personality he would not have been very happy with a book called Galileo's Error.

0:18:03 PG: That's true, that's true. Fair enough, fair enough.

0:18:06 SC: But so good, let's... I think we have interesting things to talk about. So let's quickly dispatch what I think is the least interesting thing, which is the idea of dualism, right? The old fashioned Cartesian idea that there is a mind distinct from the body without localization in space or time immaterial that somehow talks to it. So you're not in favor of that and neither am I. So let's explain why.

0:18:33 PG: So I think maybe the problems of dualism are perhaps of a more straightforwardly scientific form. So maybe the problems of materialism are more philosophical in nature. Problems of materialism, of dualism, sorry, are more straightforwardly scientific. So most dualists, although they think the mind and the brain are distinct, they also want to hold that they stand in an intimate causal relationship. So that when light hits the retina of the eye, makes changes in the brain, which will bring about visual experiences in the soul or vice versa, the decisions of the soul to raise the arm, make changes in the brain and cause the arm to go up. So there's an intimate causal relationship there.

0:19:19 PG: So from my point of view if there were an immaterial entity impacting on the brain every second of waking life, I think that would really show up in our neuroscience. There'd be all sorts of things happening in the brain that had no physical explanation. It'd be like a poltergeist was playing with the brain, and I think that's not what we see. And so I think that gives us an ever-growing sort of inductive argument against dualism. I wouldn't want to completely stop taking dualism seriously. In my mind I think they're a lot of, including David Chalmers himself, there's a lot of interesting work done on this, but to my mind it's got a bit of a hurdle to overcome with those kind of problems.

0:20:08 SC: Yeah. And I completely agree with everything you said, and I said similar things in The Big Picture. Just... Again, because people might have some familiarity with the discourse here, there is a distinction drawn between property dualists and substance dualists. Property dualists, thinking that there is truly... The mind is truly another kind... Sorry, substance dualists thinking that the mind is truly another kind of substance, whereas... And I don't think that Chalmers is that, but property dualists thinking that there are different kinds of properties that physical stuff has, physical properties and mental properties. And I think that Chalmers, to the extent that he will allow himself to be pinned down to any actual position, is probably something closer to that, and maybe you have some sympathies along those lines too.

0:20:51 PG: Yeah. This tends to... The property dualists position tends to go along with, at least in David Chalmers' case, a commitment to special psycho physical laws. So if you just have the laws of physics, the thought is, you wouldn't have consciousness, we'd all be zombies. But these special psycho physical laws that are as fundamental as the laws of physics, because those laws are governing when you have certain physical states of affairs, they give rise to consciousness. Actually, let me say, it's interesting to say, often when I'm talking to people who consider themselves materialists, they will often say, "Oh, yeah... " They often take that to be the view that the brain produces consciousness, but that's not materialism, that's dualism. If the brain produces consciousness, then consciousness is this extra stuff.

0:21:48 PG: So I actually think, at least among the sort of people who are just thinking about this in general, I think a lot of people who think of themselves as materialists, actually turn out to be property dualists. And when... I've found, actually, when I explain to them what materialism is, they're like, "Oh, no, that's crazy!" Of course that's actually...

0:22:09 SC: They're horrified? [chuckle]

0:22:11 PG: So yeah. So you might find actually...

0:22:13 SC: But this is exactly why philosophy is important, right?

0:22:15 PG: Yeah, sure.

0:22:15 SC: Because people think that they have a view on something, and they haven't really thought it through, and they talk in sloppy ways...

0:22:19 PG: Exactly.

0:22:20 SC: And so you can analyze what's going on and go, "No, no, no, your implications are not quite what are implied by your assumptions."

0:22:26 PG: Sure. Absolutely, yeah.

0:22:29 SC: Okay, good. So let's not even spend too much time, we should pause to give credit to Princess Elizabeth, who was the first to raise this problem of how the immaterial mind is supposed to interact with the body, which is now grown up to be called the interaction problem. And are there many actual hard core substance dualists hanging around these days in philosophy departments?

0:22:53 PG: Yeah. Just a quick word on Princess Elizabeth. So she was expressing worries about the intelligibility of the relationship between something physical and something non-physical. I think most people these days don't worry so much about that, it's more of... That will be a more philosophical worry. The worry these days is more an empirical concern of the sort we've been talking about. Are there many substance dualists? Actually, I'm not so sure Chalmers is not unsympathetic to substance dualism, actually. Definitely, Martine Nida-Rümelin, who is in the University of Fribourg in Switzerland, is an excellent philosopher and substance dualist of some kind, who... But she's, as I say in my book, she's a passionate atheist and she just thinks that the conscious mind is not physical, but it's a natural phenomenon that arises from the physical, and it's law governed. And so I think actually she's motivated to substance dualism at least in part because of thoughts about identity over time.

0:24:06 PG: I think some substance dualists, and maybe we don't want to get into all that, but some people are worried about...

0:24:11 SC: But once the wave function of the universe starts branching into multiple copies, it raises a whole another conundrum for those kinds of things. [chuckle]

0:24:18 PG: Yeah, you're not going to be worried about it in that case. So I think that might be part of the motivation of such people, but yeah.

0:24:25 SC: Alright. So brushing that aside, hundreds of years of very difficult work in philosophy and consciousness studies, materialism. So we have the idea post-Galileo, that we're made of these things, we can describe them mathematically. There is this... Always this slight footnote to trying to be a good materialist which is that, what we think the material actually is changes over time, right? Like Galileo would have thought it's one thing, and then atoms came along, and then quantum mechanics came along. So it's hard even to pin down what you mean by materialism or physicalism, I will grant that.

0:25:04 SC: But I think the basic idea is that, there is stuff, the stuff obeys laws of physics, the laws of physics are impersonal, right? They're equations, maybe differential equations, maybe something more advanced than that, and that's it. In some level we could talk about the entire world in just those terms, but that then there are other higher level ways, sort of useful effective theories or whatever you want to call them, which come closer to our folk view of the world, where there are people and intentions and thoughts and so forth. So you're not on board with that very sensible perspective, do you want to give us your favorite arguments against it? Oh, yeah.

0:25:42 PG: Actually, I'm not... I don't want to get lost...

0:25:43 SC: Don't want to put words in your mouth, yeah.

0:25:45 PG: Lost in definitions at the start. Actually, I'm not sure any of that was inconsistent with panpsychism you said, actually.

0:25:54 SC: I did say all there is.

0:26:00 PG: Well, maybe we'll get to that. The way I would define materialism actually, I don't know whether you sympathize, is that the fundamental nature of reality can be captured with a purely quantitative vocabulary involving just mathematical and causal terms. So that's at least part of the definition. Would you be happy with that?

0:26:24 SC: Well, I'm willing to be happy with it. When you say it out loud, it strikes me as odd because we're trying to define materialism and the operative words in your definition were things like math and quantitative. And that seems to be a slight sliding of what you're really aiming at here. I mean, my definition, whatever it would be, and I don't claim to have the world's most perfect definition, but stuff obeying the laws of physics, and that's a complete description. Like there's no extra properties over and above the physical properties. That's the important thing for me.

0:27:00 PG: But, the panpsychists think that as well.

0:27:02 SC: Well, we'll get there. We'll get there. Okay. Good.

0:27:05 PG: Yeah, yeah. Let's come back to that.

0:27:06 SC: So, let's put it this way. Let's operationalize it. You don't agree with materialism, so tell me why you don't agree.

0:27:12 PG: Yeah. Sorry, philosophers get lost in pedantry.

0:27:16 SC: No, it's important. I'm very happy to do that. Yeah.

0:27:18 PG: Okay, so it really comes back to what we were talking about earlier. So maybe here's another way of putting it. I know from your perspective... So what is the job of a theory of reality? What are we trying to... What's the data for a theory of reality? And I guess I think you'd think that the data is the data of observation and experiment. Right? If you've got a theory that can account for... Very roughly, maybe you want a nuanced one.

0:27:48 PG: If you can account for all of the data of observation and experiment in the most satisfying, elegant, simple way, job done. Whereas I think that's not enough. There's something... There's another bit of data. There's something else we know to be real, namely consciousness. And it's not something we know from observation and experiment. If you look inside someone's head, you can't see their feelings and experiences. So, if your aim is just to account for observation and experiment, then you'd never have any reason to postulate consciousness, as I think Daniel Dennett is wonderfully consistent on this.

0:28:29 PG: But we do know that consciousness exists. We know it from our immediate awareness of our own feelings and experiences. In fact, I think Descartes was right that the reality of consciousness is known with a greater certainty than anything about the external world. And that's an extra datum that needs to be accounted for. And we can't assume from the start that the postulations we made to account for observation and experiment will also account for this other data. In fact, in a way it'd be strange if it did given that what you deal in, the postulations you deal in are tailored for a specific purpose, explaining observation and experiment. It would be kind of a weird coincidence if they also explained these subjective qualities that we're aware of in a completely different way.

0:29:20 PG: So that's just a sort of prima facie thing. But then coming to the crux of it, I think there's good reason to think that the postulations of physical science alone cannot account for the reality of consciousness and again it's coming back to the issue that consciousness has a purely... Sorry, consciousness has a qualitative nature whereas physical science deals with this purely quantitative vocabulary.

0:29:50 PG: So, let me put the point again in a slightly different way. You cannot convey... So, I don't think it's just that... When people have heard about Dave's hard problem, sometimes they think, "Oh, we just haven't got the solution yet." But I think that's... Not to get to the philosophical core of this. The problem is, you cannot even capture the qualities of consciousness in the language of neuroscience. And one way to see that... If you could, if you could capture what it's like to see red in the language of neuroscience, you could convey to a blind from birth neuroscientist what it's like to see red, the qualitative character of red experience, which seems absurd. You can only know what it's like to see red when you actually have a red experience.

0:30:40 PG: So I don't think you can even... Because of its limited vocabulary, I don't think you can even capture the qualities of consciousness in the language of neuroscience. So that's a kind of expressive limitation. And I think that expressive limitation implies an explanatory limitation, because if you were going to explain the qualities of consciousness in the language of neuroscience, it seems to me you'd have to convey those qualities in the language of neuroscience and then explain them in more fundamental physical terms. If you can't even convey them, you can't even express them, then I don't think you can explain them.

0:31:17 PG: So I think there are good in principle reasons to think neuroscience alone, physical science alone because of its quantitative vocabulary can't give us a complete account of this phenomenon we know to be real. So it can't be complete and it can't be true.

0:31:40 SC: Yeah and I think... Good. This is exactly what I really wanted to dig into. I completely agree that consciousness is real. I've never been very sympathetic to people who said it was an illusion. I mean, Dennett, I think he's maybe less consistent or less clear than you give him credit for. Because he gets upset when people say he denies the reality of consciousness. But he does sometimes seem to be calling it an illusion. And I'm not sure where to land.

0:32:06 SC: But I don't think it's an illusion. I think it's a higher level emerging phenomenon, but I think that's a very different thing. So I'm torn. I'll give you two choices. I want to talk about zombies. I want to talk about intrinsic natures. Which do you think makes sense to talk about first?

0:32:23 PG: Let's go with zombies.

0:32:25 SC: Yeah, before answering, because I want to get into the details of what you just said, but a nice little thought experiment on the table would be useful. So give me your version of the zombie argument.

0:32:36 PG: Yeah. I mean, I don't tend to... You prefer zombies rather than Mary?

0:32:43 SC: I think, yeah. No, Mary's easy. Even Frank Jackson who invented Mary gave up on her eventually, so I think I'm on firm ground there. So, why don't know tell us about Mary the color scientist?

0:32:55 PG: Yeah, I think I prefer Mary, in some way. It seems to always get... It gets very technical, the zombie argument, I think. So Mary is this...

0:33:05 SC: Sorry, just to put it on the table, I think that zombies are the world's best argument against pan psychism, which I do want to talk about that at some point. But we can talk about Mary first.

0:33:17 PG: So, I think it's really just a way of explicating and giving further support to what I've already been talking about. So, Mary is this genius color scientist who knows everything neuroscience can teach you about color experience. So, the wavelengths hitting the eyes, the changes that makes in the brain, how it gives rise to various forms of behavior. But for some reason that's never explained she's been raised in a black and white room. [chuckle]

0:33:47 SC: Yeah. The backstory, the exposition is not very good.

0:33:52 PG: I think, in a way, we could have just had a colorblind neuroscientist or something, you know? There's this guy, Nobi, who's a color expert who can only see black and white and shades of gray, and has written some interesting stuff from his own position. Anyway. Right, anyway. So, let's go back to Mary. So, she knows everything there is to know, everything neuro... Sorry, I should say everything neuroscience can teach you about color experience, and then one day, but she's never actually seen colors 'cause of this black and white room. And one day, again, not explained, she's liberated from the black and white room and she sees colors for the first time.

0:34:31 PG: So, the proponent in the knowledge argument says, "At this point she learns something new. She learns what it's like to see color." One problem with this is, so that's the story, and because the story is so simple, I think people are often too quick to think they've got the argument. But so, here's the argument, the knowledge argument that's based on this story. The thought is if materialism is true, then in principle, neuroscience ought to be able to give us a complete story of the essential nature of color experience, a complete account of what's going on. Mary, by stipulation, knows that, so there ought to be nothing more she can learn about the nature of color experience. She knows it all.

0:35:22 PG: The analogy I give in my book is if you've got the complete final theory of black holes, right, you ought to be able to, it ought to be the case that you can't learn anything new, any new essential features of black holes 'cause you've got the complete final theory. So, it ought to be, if materialism is true, there's nothing more that Mary can learn. And yet, when she comes out of her room, she does gain some new information about the essential nature of color experience. She learns what it's like to see color, and this is information that couldn't be got from the neuroscience. And so, in some sense the neuroscientific account must have been incomplete because there's information about color experience that goes beyond what the neuroscience can provide.

0:36:12 PG: And then, so, just to link it back to what I've been talking about a lot already, what is that information? What did she learn? She learns about the qualitative character of colors, the redness of a red experience. That's what a congenitally blind neuroscientist, no matter how much neuroscience they learn, will never know about. So, there's information there that goes beyond what neuroscience can capture. That's that. Sorry, it was a big long-winded.

0:36:39 SC: No, no, this is good. So, here's what I would say about that. I have a long thing to say, but let me just say the short thing. If Mary knows everything about the neuroscience of color, that is to say what exactly happens in a human brain when a human being looks at something that is red, clearly that is different from experiencing red. No one argues with that. And so, the analogy, to me, is, if I give you all the laws of particle physics and atomic physics and gravity and so forth, and you know them and you have the equations in front of you, and then I say, "Okay, tell me about the life cycle of a star." Well, that's, in principle, you could figure it out. In practice, there's an enormous amount of work to do. In principle, Mary could say, "Okay, all I need to do is to have my neurons fire in the following way, which are the ways that they fire if I were seeing red. So I will hook myself up to the correct electro-stimulator machine and I will make those neurons fire in the right way and I will experience the experience of red." And I don't see anything in there that gets in the way of being a materialist.

0:37:51 PG: Yeah, but if you learning the theory of black holes... So, yeah, I completely agree. I think this is... I think there's a little bit of... People always think the argument is about... I've heard, about the change in Mary, that, "Oh, how come she can't... She knows all the neuroscience, how come she can't experience red?" That's not the argument. Of course, of course the materialism, the materialist does not have to deal... That's not a problem for materialists. But notice the disanalogy. To know the relevant facts about black holes, you've picked a complicated example, but... Let me start again.

0:38:35 PG: To know all the facts about black holes, you don't have to become a black hole. [chuckle] It ought to be the case that you can know everything there is to know about color experience from the neuroscience in materialism's view. Not saying you ought to be able to experience colors. No, that's not the point. You ought to be able to know all the facts from the neuroscience, and you've just conceded that you can't do that. You have to... She has to have changes in her neurons. Why does she have to do that if materialism is true? If materialism is true, all the information should be there in the neuroscience, and she's got it. You don't have to turn yourself into a black hole to learn the theory of black holes. Why do you have to make changes to your brain to know the full theory of what color experience is?

0:39:23 SC: Yeah. I think that's because you've set up the question a certain way. You need to be a black hole to know what it is like to be a black hole. And, of course, the difference, which I completely agree with, is that black holes don't have self-awareness or thoughts or anything like that. So, you can argue that there isn't anything that is like to be a black hole. I can see that there is something it is like to be a person, but that's because we have the capacity to hold in our brains representations of ourselves and attitudes towards things. And therefore it's not... I would say that's not a very good analogy. There is something that is different, even if you're a materialist.

0:40:06 PG: Do you think there's information, Mary in her black and white room, do you think there's information about the nature of color experience she doesn't have?

0:40:17 SC: In principle, no, but again, I'm conceding that it is different to know a bunch of facts about neuroscience and to experience something. I just think that from knowing those facts about neuroscience, you can experience something without actually experiencing it, you can make your brain do the things that it would do if you are experiencing it. And that would be the same as actually experiencing it, because all that's happening is things that are happening in your neurons.

0:40:42 PG: So I think there's two different things going on here. One is a question of complexity, the in principle question, and that was your life cycle of a star or what was it, the life of a star?

0:40:53 SC: Yeah.

0:40:53 PG: And this is something Dennett often presses. And I think it's a little bit of a red herring. It's maybe an unfortunate consequence of the way Jackson set up the thought experiment. He said, she knows everything physical, every quark and every, but I don't think you need to set it up like that. Presumably, the future's neuroscientific theory is just going to be a natural extension of what we have today. So I don't think it's implausible to think a normal human being could know that. So I don't think... So I think we can set on one side these worries about in principle knowing. The point is, as you accept, there's some information here that you have to make changes to your brain to get that information. And I'm suggesting if materialism is true, that's weird. Why would you have to make changes to your brain to get the information? So let me put it, we're all agreeing that you have to make changes to have the experience but I suppose the way... Why do you have to have the experience to get the information? That's the question.

0:42:02 SC: That doesn't seem even a little bit surprising to me, like I could tell you in gruesome detail the correct way to shoot a free throw in basketball, and you can sit at your desk and you can study everything there is to know about shooting a free throw. And if you've never shot a free throw before, you're not going to be very good at it, because the way that we learn things through our eyes and our ears and recording information is just different than how our body reacts to these things. It's not surprising as a materialist.

0:42:30 PG: Okay, good, good. Now what you're presenting, I think, is what's known as the ability hypothesis response, right, which is originally by, what's his name? Nemeroff, Leonard Nemeroff, was it? And but it was defended by David Lewis, who's quite a big figure in philosophy generally. So anyway, the view is here. So I keep trying to press on you information. There's information Mary can't get in her black room. But what Lewis says, and Nemeroff, she doesn't gain new information, she gains new know-how, new abilities, that's what she learns. She learns how to imagine red, categorize things as red, remember red and so on. So she gains new know-how. Now, that's a perfectly good response because then, yeah, neuroscience gives you all the information. She just gained some new abilities, that's not a problem for materialism. Okay, so I think there were a couple of problems with this response. Do you want a technical one or an intuitive one?

0:43:40 SC: Give us both. Give us whatever you think you want. I'll let you decide. Technical is fine. We have an hour long here, plenty of time.

0:43:48 PG: The technical one is, it seems you can put these sentences about what it's like to see red into deductive syllogisms. So you could say, Mary could say, this is what it's like for me to see red, and this is what it's like for Billy to see red. This is what it's like for me to see red therefore it is what it's like for Billy to see red. So there's a valid truth-preserving argument there, and I forget whether the premises are true or false. But that seems to show that these "what it's like" sentences are truth claims. And the problem with the ability hypothesis, is it doesn't have any account of that. It just talks about abilities, but abilities are not the same as truth claims. So that's the sort of technical...

0:44:37 SC: Well, this is actually, I mean, maybe it will be helpful to talk a little bit about intrinsic natures, which I mentioned before, and you talk about it in the book, because I think that this is the fundamental underlying issue that we have, that Galileo and I have with you and panpsychists. The idea that...

0:44:54 PG: Galileo is on my side.

0:44:56 SC: Well, I could write a book saying you made an error, so you know.

0:45:01 PG: Yeah, sorry.

0:45:01 SC: You've built your house, you've got to live in it.

0:45:02 PG: Sorry, I'll stop interrupting now.

0:45:05 SC: I think yeah, so well, I mean, why don't you say, I shouldn't put words in your mouth. Why don't you tell us what you mean by the idea that physics doesn't tell us, physics tells us what things do but it doesn't tell us about their intrinsic nature. And this is also, it goes back to Bertrand Russell, right? I actually learned from your book that Russell was one of the big names in panpsychism, I didn't know that.

0:45:33 PG: Yeah, well, actually, Russell, as I put in some of the footnotes, didn't quite have a panpsychist interpretation of it.

0:45:41 PG: He didn't quite get there, yeah.

0:45:42 PG: It's as close as damnit, just because he had some funny terminological issues, but anyway, yeah, so I think actually there's been a real resurgence of interest in panpsychism in academic philosophy in the last 8-10 years. It's gone from being laughed at insofar as it was thought of at all to being taken quite seriously, and I think this is largely due to the rediscovery of this work, important work from the 1920s by Arthur Eddington, scientist, and Bertrand Russell. So I'm inclined to think these guys did in the 1920s for the science of consciousness what Darwin did for the science of life in the 19th century, and it's sort of a tragedy of history that it got kind of forgotten about.

0:46:28 PG: Okay, so the starting point is, as you were just alluding to, that physics tells us a lot less than you might think about the nature of physical reality. So in the public mind physics is giving us this complete story of the nature of space and time and matter. But what Russell and Eddington realized is actually upon reflection, it turns out that physical science is confined to telling us about the behavior of matter, about what it does. So physics talks about mass and charge, we characterize mass in terms of gravitational attraction, resistance to acceleration, charge is characterized in terms of traction and repulsion, this all concerns what particles or fields do. Physics is completely silent on what philosophers like to call the intrinsic nature of a physical entity, how it is in and of itself independently of its behavior.

0:47:35 PG: And so this is sometimes called the problem of intrinsic natures, it looks like there's this huge hole in our scientific story of the universe. And then just to link to consciousness very briefly, I think the genius of Russell and Eddington was to bring together two problems that on the face of it have nothing much to do with each other, the problem of consciousness and the problem of intrinsic natures. So the problem of consciousness is roughly a need to find a place for consciousness in our scientific story, the problem of intrinsic natures is that we have this huge hole in our scientific story of the universe. So the unified solution is put consciousness in the hole.

0:48:20 PG: So we're looking for a place for consciousness. We've got this big hole, put consciousness in the hole. So the resulting theory is a kind of panpsychism, just matter or just physical stuff, fields maybe, there's nothing spiritual or supernatural, but physical reality can be described as it were from two perspectives. Physical science describes it as it were from the outside, tells us rich information about its behavior, but as it were from the inside its intrinsic nature is constituted of forms of consciousness. So this is a beautifully simple, elegant, unified way of integrating consciousness into our scientific worldview, and in contrasted dualism it's consistent with everything we know empirically. So from my perspective, just final sentence, we've got this challenge of how do we bring together what we know empirically about the physical world from natural science and what we know, this qualitative reality we know from our immediate awareness of consciousness, this gives us a way of bringing them together in a way that's entirely consistent with both. Yeah, so that's the big picture of the view I try to defend.

0:49:35 SC: Yeah, and I think the reason why I wanted to bring that up right now is because it is the underlying to me, the underlying source of all of our other disagreements in some sense. I totally would buy the idea that once you've told me what this stuff does, you're done, there is no anything else, there is no such thing as the intrinsic nature of stuff. And I think, maybe this is where you can educate me, I think that reflects back onto our discussion about Mary, whether or not... Or just more generally what it is like to be something. I think what it is like to be something, what it is like to experience red ultimately is a description of certain things going on in our neurons in our bodies.

0:50:23 SC: And I don't have a strong opinion about whether or not there are truth claims associated with that that are inter-mind, the old question of whether the red I see is the same as the red you see, I'm not sure whether it has a sensible explanation, but I do think that when I'd say I'm experiencing red, that not only correlates exactly with certain neurons doing something in my brain but is just a way of saying that certain neurons are doing something in my brain. So I think that is the same as the intrinsic nature disagreement. Is that fair?

0:51:01 PG: Let me just say one thing which I wouldn't... I think you do have a coherent position and I wouldn't describe it as denying the reality of consciousness. I think you, you had these dialogues in your book of people think that's denying consciousness and maybe some of my antiphysicalist comrades would say that, but if that view works out, I think it's clearly accepting the reality of consciousness, I just don't think it's ultimately coherent. But that's just a brief point. I'm not inclined to agree that this comes down to whether we need intrinsic natures. To my mind that's a distinct and more contentious view. I can imagine being persuaded, we could look at some of the arguments if you want as to why we need to postulate intrinsic natures at all, but I can imagine being persuaded that sure, we don't need... There's a coherent picture of the world in which there's no intrinsic natures, and so on this kind of view things are just doings rather than beings, once you've said what it does, you've said everything.

0:52:15 PG: But I still think... I would think, well, this qualitative reality, what about these qualities? We need some account of them, and I haven't yet heard an explanation in physical science terms. And I would push these arguments that there are in principle the reasons to thinking that can be done. So I guess I would be inclined to think these are distinct issues.

0:52:50 SC: Where it became unclear to me is when you bring up the qualitative features, the qualitative experiences and so forth, maybe I'm getting this wrong, but it at least reminds me, resonates with the idea that there is something over and above what the things are doing, and maybe it's not intrinsic nature, it's still something over and above what things are doing.

0:53:11 PG: So maybe put it like this, I think there are two reasons why we need intrinsic natures. One, I'm not sure it's intelligible to have a picture of the world without them, forget about consciousness, and we could get into these arguments may be or not. But the other is there is this reality we know about and it's hard to see how you can account for it in causal structural terms. But that's in a way... There's two steps to that argument, one is there is this data and we need to account for and secondly, to my mind they are good arguments why it can't be accounted for in causal structural terms. So I suppose there, yeah, you get the implication that it's a kind of intrinsic nature. Yeah, yeah, maybe that's right. But it's...

0:54:12 SC: Maybe it is worth... I want to give you a chance to give the positive case and explanation for panpsychism, which we've kind of only alluded to so far, but I think because I do think that this kind of divergence is at the heart of all of our divergences, maybe it is worth saying some words about why you think that intrinsic natures really are necessary. If I knew all of the mathematical structures and causal relationships among the physical stuff of the universe and could say what everything did, there would still be something lacking. So I don't think there's any lacking once that happens, and you do: Tell us why.

0:54:50 PG: Okay, let's get into that argument, but I think I've just clarified to myself what's going on, so let me... I think it's... You seem to be saying that the... I believe in intrinsic natures because I think consciousness is irreducible, not the other way around. It's not like I start off saying, "Oh, there must be these intrinsic natures." It's because of consciousness. But also I do think there must be intrinsic natures. So maybe we could get into the argument. People...

0:55:20 SC: It might be logically separate, but they are in the same spirit, that's all I would say, those two facts.

0:55:25 PG: Yeah, it's an interesting thought, it might be something I might have to think a little bit more about. People defending this Russell-Eddington picture going right back to Russell, have tried to defend this kind of argument to the conclusion that a world without intrinsic natures is just unintelligible. And I go a little bit back and forward on these arguments I have to say, I'm not 100% committed, but the thought is without intrinsic natures everything ends up being defined in terms of everything else, and you end up in a kind of vicious circle. I have an appendix to one of the chapters of my book on... So the thought is you start up saying what's mass? And you say, let's just keep things simple, let's ignore general relativity, and you just say, "Oh, it's... It causes gravitational attraction." And then you say, "Okay, well, what's attraction?" And you say, "Well, it's... It's when... I don't know, the distance between bodies is decreased." And you say, "Well, what's distance?"

0:56:31 PG: And then you get another bunch of equations that explicates distance in terms of other physical properties like mass and charge, and you quickly find yourself back in a circle, and without any way of getting an independent grip on any of these properties, it looks like these definitions just don't get off the ground. So the analogy I give in the book is, suppose I've got three matchboxes and I say, in the first one there's a splurge, in the second one there's a blurge and in the third one there's a curge. And you say, "What's a blurge?" And I say, "Oh, that's easy, the blurge is something that makes blurges."

0:57:07 PG: You say, "Okay, well, I don't know what that means until I know what a splurge is, what's a splurge?" And I say, "A splurge is a thing that makes curges." And you say, "Well, I don't what that means either till I know what a curge is." And I say, "Well, it's a thing that makes blurges." And you don't know what the hell is in the matchboxes. So I sort to think that's actually how... And this is how Russell thought, this is actually how physics works, everything's inter-defined. And so without a kind of independent grip we don't really get an understanding of what any of these things are. So that was the kind of argument he pressed. What do you reckon?

0:57:41 SC: Yeah, I'll just very quickly say why I do not find that argument convincing, but I'm glad that it's out there. I agree that an individual term like mass can't be defined without talking about other things, there's absolutely interconnectedness, but rather than circularity, I would just say one defines an entire formal system, spacetime is a four-dimensional manifold, Lorentzian metric, blah blah blah blah, and there's a whole bunch of individually, very well defined parts of that formal system, and then one maps it onto the data of our experience and says we've explained the world. I don't think it's circular, I do think it's interconnected, so I'm not convinced, there you go.

0:58:24 PG: But what if I say what is a field? Tell me what a field is.

0:58:29 SC: Oh, a field is a section of fiber bundle. There is a mathematical formalism and I can pinpoint individual parts of it, so I don't care to talk about the intrinsic nature of them, that's my escape hatch. If I don't care about what it really is, if I just care about where it is in the math, then I'm done.

0:58:50 PG: Even if you're taking... Yeah, so look, this depends... There are a couple of different issues here, one is there are two subtly related views. I guess you're defending a kind of... What's sometimes called ontic structuralism, that in some sense is just structure, but there are two closely related views here, one is a pure structuralism where there's just what can be captured mathematically. Another is causal structuralism which is a little bit more modest, it's what can be captured with mathematics and causal terms. And in that view we ultimately define the nature of things in terms of what they do. Would you say that you were going for the former or the latter?

0:59:38 SC: I think I'm the former. Yeah. I'm not a big fan of causal terms and fundamental ontology.

0:59:44 PG: Right, right. So the world can be just entirely captured in mathematical language?

0:59:51 SC: Yeah. So there is the world, and there is a mathematical formal system, and there's an isomorphism between them. And it's all complicated and philosophy is necessary, because there's also our folk experience of the world, which is like a third thing that we have to map on to both of those in interesting ways, but it's a coherent set of interconnections, not a circular argument. That's the interesting thing.

1:00:14 PG: Okay. Well, I think in that case maybe we, 'cause you're sympathetic to a kind of Humean... I think maybe we've been talking slightly at cross purposes, because that argument is more an attack on people who want to take causation as a fundamental feature. And we define the nature of, say, an electron, in terms of what it does. Yeah. I think that problem goes away a little bit if you just think... And in fact, there has been a reply to, there's a volume of essays on this form of panpsychism, and Alyssa Ney, who's a philosopher, a very good philosopher of physics, is replying in exactly these ways. Arguing that we could just have the wave function or something expressed in completely mathematical language.

1:01:03 SC: Just parenthetically, I am the author of an idea called Mad-Dog Everettianism. Where literally all that exists is a vector in a giant Hilbert space representing the universe, and Hamiltonian tell us how it evolves. And everything else, space, time, matter, particle fields, are just particular human constructions to conveniently talk about what that wave function does over time.

1:01:29 PG: Sure. Yeah. So I guess at that point... What I would say is okay maybe... Are you familiar with Newman's problem. Have you heard that discussion?

1:01:47 SC: I've heard of it, but I couldn't explain it. So why don't you explain it. Yes.

1:01:50 PG: Well, the problem is I can't remember the details either but... So the way I've thought about these things, is the causal structuralism faces this regress problem, and the more pure structuralism faces Newman's problem. But, it's a while since I've looked at the details. So I don't think I'd be able to defend that, but let's say you persuade me that the Mad-Dog Everettianism you just described is... Describes a possible reality. And that that theory can account for data, all the data of observation experiments. Then I'd say fine, that's fair enough, but I'd say, well, look there's this other datum. How do you account for this, of the qualitative reality of consciousness, and then we'd be back to the knowledge argument. We'd be back to my claim that you can't account for that in a purely quantitative vocabulary.

1:02:53 PG: So in a way, look, I just think the reality of consciousness is a datum in its own right, over and above the data of experiments and observation. If you've got a theory that can account for all the data of observation experiments, but you can't account for this, then your theory doesn't work. And you said, I guess you've said okay of course you're not going to want to deny consciousness, but in all of the cases that's an option. That there are lots of phenomena that are difficult to fit into our scientific world view. Facts about value that I know you're interested in, facts about free will, abstract objects, solidity in some sense, maybe our folk notion of solidity, or our folk notions of time, in all of these cases it's at least an option to either deny the phenomenon, or revise our understanding of it.

1:03:51 PG: Maybe there aren't really facts about value. Maybe we're not really free in the way we think we are. Maybe time isn't how we thought it was. But I think with consciousness it's a reality that we know in such a direct way, that I don't think it's an option to either deny it or revise it. So I think it's... It has a very special place in our methodology, and because of that one needs to be hesitant about whether the stuff we postulated to account for observation of experiments, can also account for this. And I haven't heard from you yet a story about how that's done. You've said that it can do it, but you haven't told me how it does it.

1:04:36 SC: Well, yeah. I don't think we've done it yet. So there you go, and I'm very happy to admit that. But the extent to which I'm impressed with materialism is just so vast that of course consciousness being involved with the most complicated structures we know of in the universe will be the last thing that science successfully explains. Not because it requires something separate, just 'cause it's hard. That's why it's hard, but anyway I think we could get stuck here. Rather, I want you to... Really, here is the chance...

1:05:09 PG: Can I just say something briefly.

1:05:09 SC: Sure, sure.

1:05:09 PG: I think that's where it comes back to the Galileo point precisely. Maybe let's not get to... It's that yeah, science is so impressive, but it's impressive at a very limited task, describing the behavior of matter, roughly, mathematical models that capture. It was never in the business of accounting for these subjective qualities that we're immediately aware of. That's never what it's been doing. To say oh, it's been good at this one thing, so it's going to be good at this other thing, I just think there's something confused going on there. I mean, I have this analogy in my book that when I was... My first year as a lecturer, the head of department very kindly let me off administration, and I was pretty good at the other aspects of the job. I was pretty good at teaching and pretty good at research. The fact that I was good at teaching and research doesn't give you any reason to think I'm going to be good at admin, right?

1:06:02 PG: So similarly, the fact that physics has been really good, physical science more generally, really good at these mathematical models to describe behavior, why does that give you any reason to think it's going to be able to capture these subjective qualities that we're immediately aware of? Anyway. Sorry.

1:06:18 SC: No, no, actually, that's wonderful. I'm glad you said that, let me respond to it and we'll see whether or not we can restrain ourselves from going back and forth. I think that's crucially important because when you have something like consciousness, it's like when you have any part of scientific explanation or broader philosophical explanation that isn't finished yet, right? We admit that we don't have the full understanding, none of us does, and therefore as individual scholars and researchers, we make bets, we have credences about what is the most likely future path of progress. And I talk about this in my upcoming book. I kind of breezed through it in The Big Picture but in Something Deeply Hidden, where I'm talking about quantum mechanics, I think that it helps illuminate why some people are cheerful Everettians and some people find it to be abhorrent and therefore go for hidden variables or something like that.

1:07:11 SC: And it's because we do have the world of our experience, our sort of objective data collecting experience and our subjective inner experience, let's lump it all into one thing, and we haven't yet fully explained it and which is more likely among the following two options? Number one is an explanation that is more or less close to the phenomena that we're observing, like the structures within the explanation, there's a lot of them and it's kind of a complicated set of things going on, but the map between those structures and what we experience and what we see is very clear and crisp and easy. That would be a hidden variable approach to quantum mechanics where of course, there's particles and waves in the double-slit experiment 'cause there's particles and waves in my ontology.

1:08:00 SC: Or the other option is you have an extremely beautiful, austere, simple, powerful underlying formalism, but the road from there to explaining the world of our experience is long and fraught with peril, right? That's the Everettians perspective where, like I said, you just have one vector in a big Hilbert space and you have a lot of work to do to say why the world looks like three dimensional space plus time with fields and all that stuff. And either one of those options is very much on the table and there is a matter of taste or style that comes into saying, "Oh, I'm pretty sure it's this one," right?

1:08:36 SC: And I think it likewise for consciousness. Of course, we have not explained consciousness in any convincing way as materialists, but I have no trouble believing that it will eventually happen, because materialism is so beautiful and elegant and so powerful. And I get, even if I don't agree with, the perspective that says, "I just don't see how we'll ever get here from there." And I think that's a perfectly valid perspective and will... I think that progress will be made and we'll figure it out.

1:09:08 PG: And do you think that when we get the final physical explanation, it will be able to convey to a congenitally blind neuroscientist what it's like to see red?

1:09:20 SC: By going in and manipulating their brain, yes. Not by talking to them.

1:09:25 PG: So it can't give all the information?

1:09:28 SC: Just like I can't teach someone to be a good free throw shooter by talking to them either.

1:09:34 PG: Okay. Let me, and this is not getting back to it, but I mean, I completely agree with that whole thing you just said with every phenomenon except consciousness, because I think every other phenomenon is capturing the causal structure of the universe but this is... We don't know about it in that way. We know about it in a very different way, and so I think that gives us the entitlement to give a different credence to it because we have a very different epistemological relationship with it. I think we apprehend its reality directly and we know something about its reality directly. I think when I attend to the qualities in my experience, I know something about their nature. I don't have that with tables. If I had that with tables, if I could magically know something about their nature, then maybe that would give me less credence than physical science can explain it but I don't have that. It's just, but with consciousness I think I have some direct access to its nature. And so that's why I think I can have a very different credence in the possibility of physics. I ended up coming back to the argument I said I wouldn't. Sorry.

1:10:47 SC: I know, and I'm biting my tongue. I have things to say. What I really want to say is tell us what panpsychism actually says. Let's give it a sales pitch. You're at a used car dealership and it's your used consciousness theory dealership and someone has wandered onto the lot and you would like to sell them this panpsychist vehicle that you've been trying to move for a long time. What is your sales pitch?

1:11:10 PG: Well, I think in a way I've already described it. That there's just matter, there's just what physical science describes, but let me emphasize actually how non-dualist it is. Because often when people hear about panpsychism, they think... And I think actually, you said this a little bit in your book actually, that you think it's, well, the electron has its physical properties like mass, charge and spin, and it also has these consciousness properties and you rightfully said that ought to show up in our physics, these extra properties. That's not the view right, the view is mass, spin and charge are themselves forms of consciousness, right? So, physics tells us what mass, spin and charge do, but it doesn't tell us what they are, what those properties are and so it's a radically non-dualistic account and by the very way it's set up, it's going to be completely consistent with what we know scientifically. How would I sell it? Let me just... Can I say just briefly how I think about the science of consciousness?

1:12:25 SC: Actually, could you do me a favor and tell the very charming story that you told in the book of your conversion experience?

1:12:33 PG: Oh, no. My wife told me to take that out, 'cause she thought it was too cringy.

[laughter]

1:12:36 PG: No, no, it's the best part, look, you have to... It's part of being a good sales... But you don't have to, but it's in the book, I guess, so...

1:12:44 PG: I guess I've just been through various phases of always been obsessed by the problem of consciousness as far back as I can remember, and thought I was a materialist.

1:12:56 SC: But the point is you were a materialist, so you...

1:12:57 PG: I was a materialist yeah.

1:13:00 SC: You can claim to know what it's like to be a materialist.

1:13:03 PG: And I eventually came to the point of view that... Somewhat Dennettian point of view that if you're a materialist that's incompatible with the qualitative reality of consciousness, and defended that for a while whilst feeling like I was living in bad faith, that I was not really believing. And yeah, just one night and just certain vivid experiences got to me and I just decided this can't go on anymore. But actually, at that point I was taught as philosophy undergraduate, the only two options are materialism and dualism, and I thought both of these are hopeless and I was very disillusioned and I wrote my end of year undergraduate dissertation on how the problem of consciousness can't be resolved, and I went off and did something else. And then I... Panpsychism was not taught those days, and I discovered there is this elegant middle way that does accept the reality of consciousness but is completely consistent with our empirical knowledge of the world. So I think that was the...

1:14:08 SC: When you say something like mass, charge and spin are properties of consciousness, is that...

1:14:18 PG: No, they are forms of consciousness.

1:14:21 SC: Forms of consciousness, okay. What I want to say is what in the world does that mean?

1:14:29 PG: Well, I think nothing is... Some people think there's a mystery of what consciousness is, I don't think that's a mystery, I think you know, nothing is more obvious than what a feeling... You know what a feeling of pain is when you have it, you know... The mystery is how consciousness fits into our theory of the world. So human consciousness is very rich and complex. Consciousness of horses less so, mice less so. We keep getting simpler and simpler forms of inorganic life, maybe at some point the lights switch off, we have no consciousness at all, but it seems at least coherent that as we get simpler and simpler forms of matter, you have simpler and simpler forms of consciousness such as when you get to the bar... Let's just assume for the sake of simplicity, a particle ontology, which a panpsychist does not necessarily have to commit to, although you often talk about that... One often talks that way for the sake of simplicity.

1:15:28 PG: An electron has an unimaginably simple form of experience. So we can't even imagine something so simple. That seems to me a coherent view. You might think it's crazy, but it seems a realistic coherent view. Moreover, I think there's reason to take it seriously because we know that consciousness is real, we have to fit it into reality somehow. If you think materialism and dualism have got such deep problems that they're not really going to make it happen, then this gives us a way of doing it that avoids all the problems. And it feels a bit weird but so what?

1:16:06 SC: Yeah, no, weird, obviously, we're going to have to accept it if we talk about any of these things. But weird is okay, but I really want to get a better... If I were very cynical, here would be my problem. I have an electron, I have equations for what it does, it has a mass, charge and spin, I have the Dirac equation, I have quantum field theory, I can tell you exactly what it will do, as the materialist physicist I'd tempted to say I'm done, I know what the electron is and how it behaves. And you want to say, and it has some very, very primitive limited form of conscious experience, is that fair?

1:16:47 PG: But it depends on what you mean by "and." That's not a further property, I'm saying you've told me what mass does but you haven't told me what it is, that's the...

1:17:01 SC: Right, so there's something I haven't told you yet, let's just put it that way. So there's something extra that I haven't yet told you. But that something extra I haven't yet told you has no mathematical description.

1:17:14 PG: Yeah, that's right.

1:17:17 SC: And it also has... Does it have causal influences on the behavior of anything?

1:17:22 PG: Yeah, the thought is, you've been telling me this cool story about what mass does, and then the panpsychist view is mass is a form of consciousness, so it's actually, it's this form of consciousness that's been doing all the stuff you've been talking about. It's not like there's the consciousness and then there's something else, there's just the forms of consciousness and you've been telling me what they do. So it's like I don't know, you hear someone banging in the apartment downstairs and you know something's making this noise but you don't know what it is, and then you discover it's an elephant, I don't know. So you physicists study what these properties do but on this view, you're not saying what they are, that's the... Yeah.

1:18:16 SC: Maybe I'm not putting this exactly right, so mass is a form of consciousness.

1:18:21 PG: Yeah.

1:18:23 SC: Is that because everything is a form of consciousness or these physical properties are forms of consciousness? Is the wave function of the universe a form of consciousness?

1:18:32 PG: Yeah, look, it depends on what you think the fundamental ontology is. So the panpsychist view is whatever your fundamental physical story is, that will give you some structure, but then you've got to ask, well, what realizes that structure and what realizes that structure are forms of consciousness. So if you have a particle based ontology then these particles will have... If you've got a wave... Sorry, if you've got a wave function ontology then you have to think about that the wave function has its intrinsic nature as consciousness involving...

1:19:07 SC: So I was just asking, does everything have... This is part of the panpsychist view that everything has an aspect of consciousness.

1:19:16 PG: Everything at the fundamental level. So the panpsychists need not hold it like rocks and socks and beds are conscious, not every arbitrary collection of things is conscious, but everything has components or its most basic parts are conscious or the physical reality that underlies it, at least, has a consciousness involving nature, that's the view.

1:19:43 SC: But okay, I'm just trying to get straight. I as a materialist who doesn't use those words have a theory of what does happen in the world, and your theory of what does happen in the world, your theory as a panpsychist need not be any different from mine, right?

1:19:58 PG: Right. Exactly, that's taken to be the benefit of the view, we don't want our theory of consciousness to get in the way of physics, right? Yeah.

1:20:08 SC: Right. But okay, so this is where I think that the zombie thought experiment is actually helpful because if it's true that... There's different versions of the zombie thought experiment, so let me just always conditionalize on various assumptions here. If it's true that given the atoms and particles and forces in me including in my brain and my neurons and so forth, I could in principle be Laplace's demon and solve the laws of physics and say exactly what I would do, modulo quantum uncertainty and so forth, and that would include things like showing me something red, and me saying, "Oh, yes, that is red, I am experiencing red." And all that goes through perfectly well in both of our different views of the world, then I'm not quite sure what is added by the panpsychist perspective.

1:21:09 SC: In other words, let me give you the very short version of that. So the zombie is David Chalmers' idea of a physical thing that acts exactly like things in the real world, a physical collection of atoms and so forth, but that does not have consciousness. And my point is if it acts exactly the same, that includes when you ask it, "Do you have consciousness or are you experiencing things?" It says, "Yes." And if you ask it, "Are you lying?" It says, "No." So clearly it honestly thinks it's conscious but it's not by hypothesis. So by that therefore, none of us knows that we're not a zombie 'cause zombies think that they're conscious just like we do and therefore you've really added nothing.

1:21:52 PG: Okay, this sounds a little bit different to what you said the first time. The first time you simply said well, just brutally, what's the difference between a world that's physically identical and lacks consciousness and one that's... I don't know how to say it more clearly, but in the sense that when we describe physical reality, we use these quantitative concepts, when we describe consciousness we use these qualitative concepts, we talk about colors and smells and the qualitative character, it seems perfectly coherent to hypothesize that you might have one without the other, but coming to your second argument as I'm understanding it, well, doesn't this imply, none of us would know we were conscious.

1:22:41 PG: There are tricky issues here actually, just as a preliminary thought, about the relationship between thought and consciousness. So the dominant view in my philosophical tradition has been that thought has nothing to do with consciousness, and you can see this because the dominant theories of thought in the 20th century such as Jerry Fodor or Donald Davidson or Dennett, have absolutely nothing to say about consciousness, so they think you can give a complete account of thought without talking about consciousness. And so on that view...

1:23:13 SC: The more about computation and so forth?

1:23:15 PG: Yeah, some kind of functional behavioral facts or... Very, very broadly speaking. So on that view a zombie would have thoughts and would think it's conscious, as he say. But I'm actually one of a growing minority of philosophers who think actually thought is a kind of consciousness, and if that's true, then the zombie wouldn't have any thoughts at all. So that's one way you can go with this, but maybe that's getting into slightly contentious territory, but the other thing to say is... Yeah, the zombie behaves in all the same ways but I don't know about my consciousness, it's not the case that I know about my consciousness by observing myself, I know about it because I'm immediately aware of my own experiences.

1:24:03 SC: But that's just what a zombie would say.

1:24:06 PG: It would say that, but it's not true of the zombie, by stipulation. It doesn't have this... What justifies, what grounds my knowledge of consciousness is my immediate awareness of my own pain, and by stipulation, that's what a zombie lacks. Yeah, I don't know where to go with this or what to say about... Yeah.

1:24:33 SC: No, I think both of our positions are out there, that's all I ever ask for in a podcast is that people understand what both sides are saying. So let's be a little bit more future-oriented and proactive, what do you think of the prospects for consciousness and panpsychism, and you try to end the book on an uplifting note and I think it's an interesting perspective to conclude with.

1:24:56 PG: Sure, so I think this view has been getting taken much more seriously in academic philosophy. Part of the reason I wrote this book is, I've written an academic book, Consciousness of Fundamental Reality, which is reasonably well known, bringing together a lot of this recent literature, there's been a huge amount published on this view, but I really want to get it out to a broader audience, because it's not really a complete view, this Russell-Eddington view, it's a framework, and it will take decades or centuries of interdisciplinary labor to fill in the details, just as Darwin's principle of natural selection is a basic framework for understanding how life evolves, but then it takes a century to get to DNA.

1:25:45 PG: So really, I think this is going to be... I just think people are naturally conservative, it's hard to persuade people with arguments, but I just think we need to get on with this. If enough people are on board with trying to do this, and there's already very interesting work going on. Well, let me just say, actually, maybe I could just say about how I think about the science of consciousness. And this relates to materialism as well, because I think the science of consciousness has to have an empirical aspect and a theoretic aspect. I think some people think you can just do the empirical bit, but I think neuroscience, as vital as it is, just gives you correlations. To move beyond that we need to build a theory, and I think a theory of consciousness should be judged by two constraints. It's going a little bit beyond what I say in the book, actually, an external constraint and an internal constraint.

1:26:53 PG: So the external constraint is just to fit the data, obviously crucial. The internal constraint is to try and minimize or, ideally, eliminate explanatory gaps, that is, places in the theory where you're going from one set of facts to another with no account of how that happens. So the problem with materialism, materialism isn't just looking at the neuroscience, it's a theory in its own right and it has an enormous, on the face of it, explanatory gap between the quantitative properties and the qualitative reality of consciousness. I think already the Russell-Eddington view makes progress there because we now have an intelligible account of the relationship between physical states and conscious states. Conscious states are the intrinsic nature of physical states. So I think there's already explanatory progress there, but there's plenty of work to be done.

1:27:42 PG: And so the crucial next step is how we think about the relationship between particle consciousness, or consciousness at lower levels, and consciousness at higher levels. Is this a causal relationship in the sense that we need basic laws of nature to make the gap, or is this a constitutive relationship in the sense that, in some sense, the higher level forms of consciousness come for free once you've got the more basic forms of consciousness and how do we make sense of that? So there's lots of tricky issues here, and there's already really interesting work going on.

1:28:21 PG: So Hedda Hassel Mørch, who's a research fellow at University of Oslo, spent a year recently in the lab with Giulio Tononi, who is the founder of the integrated information theory of consciousness, one of the most best empirically supported theories of consciousness, working that out in the framework of Russell-Eddington panpsychism. And what we end up with is a view according to which in any system the consciousness intrinsic nature is at the level of which there's most integrated information. So I think that this works with the neuroscientific theory, but like any neuroscientific theory, if you've just got the neuroscience you've just got a correlation. But interpreting it in this Russell-Eddington framework moves beyond the bare correlation, gives you a deeper explanation.

1:29:08 PG: Another thing I talk about in the book, Luke Roelofs, who's at University of Bochum, reflecting on whether split brain patients can help shed light on mental combinations. These are the curious cases where people have the corpus callosum in the middle of their brain split, which allows their two hemispheres to communicate, it's a radical treatment for epilepsy. And it seems to lead to a kind of peculiar fragmentation of consciousness. It ends up looking like there's sort of two conscious minds in one person. So Roelofs' interest in this is, well, this split brain case is a kind of the converse of mental combination. In mental combination we're trying to understand how distinct conscious subjects can combine to a single unified conscious subject, whereas in split brain cases you've got a single conscious mind fragmenting into multiple conscious minds. So if we can sort of understand what's going on in the split brain case and, as it were, reverse engineer it, this might shed light on mental combination.

1:30:08 PG: So what we need is philosophers in labs or philosophers thinking about how do we make sense of this panpsychist view in a wave function fundamental view, which I've been actually thinking about actually for something I'm writing for an OUP volume on quantum mechanics and consciousness. So I think this needs to be an interdisciplinary labor that's just in its birth. And I think people... It's going to take a much more serious academic philosophy, although sometimes people are not entirely comfortable with this. But I think rather than persuading people with the arguments if we just get on with the work, I think history shows that once you just get on and start doing some research and this bears fruit, I think, that's when people start to listen a bit more. So I'm very optimistic that there's a lot of interesting work to be done. Sorry, that was a bit long-winded.

1:31:02 SC: Yeah, no, I like... No, no, no, it's what I was hoping for. It does sound one way or the other, whatever our bets are for what's going to happen in the future, I am optimistic that the right people are beginning to talk to each other and taking these problems seriously. Like I said, I am someone who believes in consciousness as a real thing. I would like to understand it. I don't think that we entirely do.

1:31:24 SC: Final issue, final question, very quickly. How do you conceptualize the possible moral or ethical implications of this kind of thing? I know that there's not a simple road from ought to is, but everyone agrees that science and philosophy, philosophical ideas about consciousness, could have an impact on how we think about morality and ethics. Do you have special thoughts about that?

1:31:50 PG: Yeah, a little bit. I talk about this a little bit in the final, more sort of experimental, chapter of the book. I mean, first I would say, of course, as I'm sure you'd agree, we shouldn't be thinking about which view we'd most like to be true. We should be thinking about which view is most likely to be true. And I think there's very good reasons for taking panpsychism seriously as the best account of how consciousness fits into nature. But I am also inclined to think that it's maybe a view that's slightly better for our mental and spiritual health in the kind of broad sense.

[chuckle]

1:32:27 PG: Materialism is pretty bleak in a way. You've got a kind of mechanistic picture of nature and the cold immensity of empty space and the... Whereas a panpsychist's view, we are conscious creatures in a conscious universe, it is somewhat... We can feel a little bit perhaps more comfortable in our own skin. And so actually also I think it has the potential perhaps, something I talk about in the book, to improve our relationship to the environment. If you think trees and plants are just unfeeling mechanisms, then I think inevitably your view of their value is indirect, that their value is indirect in terms of the effect it has on us conscious creatures looking pretty or, more importantly, maintaining our survival. But if you think a tree is some sense a conscious entity in its own right, then I think that's an object of immediate moral concern, it's chopping down trees something that has an immediate moral focus. So I do think perhaps this gives us... We're in this environmental crisis that we can't seem to deal with for all sorts of reasons and this might help a little bit how we relate to nature and the environment. Although, of course, that shouldn't be the reason to take it seriously.

1:33:51 SC: No, that's right. You don't accept a view because you want it to be true. But I think it's perfectly legitimate to say, "Well, I think this view is true and I'm relieved and happy that it is." [chuckle] I think that's perfectly legit.

1:34:04 PG: Sure. Yeah, yeah.

1:34:04 SC: Alright. Thanks so much. There's lot to think about here. Philip Goff, thanks for being on the podcast.

1:34:08 PG: Thanks a lot, Sean. That's been... Really enjoyed that vigorous debate. Thanks for having me.

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