 Okay, hello, good afternoon. So today is our last lecture. There's no lecture on Thursday. And all I want to do today is who is through and review all that we've done this term. So for questions, you guys have been very good at staying on point during questions through the term. But feel free to associate it, free associate it a little bit in this session, within reason. But it is meant to be a review session. So if there's some particular question that has been bugging you about some topic that comes up, do feel free to raise that in question. You see what I mean? The idea is to go back over main points of what we've covered so far. So I want to, just going through the material this time, it keeps striking me how important the idea of imagination or an imaginative understanding of the world or other people is in all the topics we've been discussing. And I have to say, I haven't quite got it in focus. But I want to try to highlight how important that idea of a distinction between an imaginative understanding of people as an objective understanding of people seems to be. And it really is crystallized most firmly in Nagel's discussion of bats, where he talks about how you can have a full objective understanding of a bat, understand cell by cell how the bat works. You could have a complete computational model of how the bat brain works and still feel that you are missing everything about what the bat's conscious experience is like. You can't imagine what it's like in there. And Nagel put the point like this. At present, we are completely unequipped to think about the subjective character of experience without relying on imagination, without taking up the point of view of the experiential subject. So that contrast between understanding imaginatively how it is for the bat and knowing objectively what's going on, that is where I think most of the big puzzles seem to come with that contrast between the imaginative understanding and objective understanding. And one of the themes I pushed was that dualism really doesn't seem to fully grasp what the problem is here. A dualist says a fully objective understanding of physical stuff doesn't give you an understanding of the mind. And looking at Nagel's bat, you could agree with that. You could have a full understanding of the bat as a physical system, but still not know what's going on with its mind. But dualism then says, well, therefore, there must be a different kind of objective stuff, an ectoplasm, and that's what the mind is. And that's not an incoherent or self-contradictory assumption. As I said, there's this book by Philip Pullman, The Amber Spyglass. Has anyone read it in the course of the term? Great. Isn't that a great book? Is it? Yes? OK. But he has this idea of, I hope I'm remembering this correctly, the golden dust that constitutes consciousness that you can see by means of the amber spyglass. And there really might be such stuff. But the thing is, if there is such a stuff, you could have a full objective understanding of it. You could observe it through the amber spyglass. Physicists would be delighted to discover such a stuff. And you could have a full understanding of that. But a full objective understanding of some second kind of stuff still wouldn't give you any imaginative understanding of what is going on in the mental life. Simply postulating another kind of objective stuff makes no progress with the problem. Yes? Well, I think the idea of this all is the idea of this second kind of stuff. And I think that's just a mistake. What I mean is, there may really be non-physical stuff. There may really be, I'm not contradicting that. But what I say is, even if there is that kind of stuff, it doesn't help with the problem, which is understanding the relation between an objective grasp of what is going on and an imaginative understanding of what is going on. Does that help? So another way to put it would be to say, you can interpret talk about the soul in two ways. You can interpret talk about the soul as saying, yeah, there is this ectoplasmic stuff, this kind of goop. And that really exists. And it's not physical. And that's fine. But it still hasn't addressed the basic problem. Or you could say, there is such a thing as the soul. But by that, I don't mean there is some other objective stuff. By that, I just mean there is this other level of understanding we have of human beings than merely as objective systems. We have this capacity for imaginative understanding of each other, knowing what it's like from each other's point of view. And if that's what you mean, that it just restates the problem, the idea of the soul. Either way, it seems to me perfectly legitimate. But the fundamental problem is still in place, whichever reading you have, namely, what's the relation between an objective understanding of what's going on and an imaginative understanding of what's going on. So that, I think, is why dualism doesn't really help. I said, I think, in the very first class, you can be puzzled about how a TV works, but simply postulating that the thing is made of a special TV stuff doesn't help with the problem. There might be a special kind of TV stuff, sure. But merely postulating it doesn't address the puzzle. So what were the, let's go back. Let's go way, way back. We've come a long time since the start of this class. It is a long time since the start of this class. There was dualism, what was next? Behaviorism, right, behaviorism. And with behaviorism, the Super Spartans point was Super Spartans, good old Super Spartans, yes, born so that they don't attend to their pens, you don't register pens, they don't express pens, but they still have them. And that was Putnam's basic objection to behaviorism. It says mental states aren't connected one to one with displays of behavior. In the case of the Super Spartans, pain might not be connected to displays of behavior at all. And I think one way you can interpret that is by saying you could imaginatively understand the mental life of a Super Spartan as involving great pain. This is something about imaginative understanding, but your imaginative understanding of other people can be disconnected from beliefs about how they're going to behave. You can imaginatively understand someone as having great pain without believing that they're going to behave in any particular way at all. So what that's bringing out, that point, is the way in which an imaginative understanding of someone can float free of their behavior. Behaviorism does say mental states are connected one by one to displays of behavior. Because that is the objection to behaviorism. Sorry, yes, this is kind of compressed, OK? With dualism, the objection is difficult to see how postulating this objective, second kind of objective style helps. With behaviorism, the objection is mental states aren't connected one to one with displays of behavior. Yep. Anything else? Nobody got attracted to behaviorism at the course of the term. Oh, I see. OK, correct. OK. Thank you. I'm glad you hear it. OK, and central state materialism says, OK, so it's not behavior, so it's rather the brain state that typically causes the behavior. That's what the mental state is identical to. So just as lightning can be identified with discharge of electrically discharge of electricity due to the ionization of the atmosphere, so you can identify pain with C-fiber filing. And then the puzzle for that was variable realizability. Remember variable realizability? Yeah. I mean, partly I just want to whiz over these key ideas, key topics, so you can pause me and raise questions at any point if you want to. But variable realizability, that's all right. The idea that there could be on earth animals like the octopus that have different brain states to ours. Maybe they don't have brains at all. There could be alien species that have emotions, feelings, pens, without having anything like our brain states. There could be humans whose brains have been damaged and then naturally rewired so that they're feeling just what you or I feel, but their brains are in quite different configurations. And again, what that's bringing out is you could imaginatively understand the octopus as having pain or hunger consistently with supposing quite a lot of different stuff about what is going on in the octopus head physically. You couldn't be certain it's actually as pain. But the take on this, I'm suggesting, is that you can imaginatively understand perfectly well the possibility that the thing is having pain, even though it doesn't have any C-fibers at all. We're talking now about central state materialism. Yes, very good. Is this a way to put it? Suppose you put together the super spartan point with the octopus point, if you see what I mean. So suppose you put together the idea that you might have no manifestation of the mental state in the display or behavior with the idea that you could have the mental state without any particular brain state, then you could have, could you have super spartan octopuses? I mean, super spartan octopuses would be bred for generations so that they don't display their pains at all. Yeah? But you can imaginatively make sense of the possibility, I guess, that these things are feeling pain, but there's no brain state there, and there's no behavior. So you have no empirical anchor for the hypothesis at all. Yeah? Is there something slightly disconcerting about what's going on if you let the imagination take on a life of its own? Yeah, I guess what I'm saying is like. I think it's not that you lose all certainty, it's that you have the objection to central state materialism with the octopus already, because the octopus does not have C-fibers. You see what I mean? But it could still be feeling pain. OK, let's take this slowly. Suppose it does display the behavior. Right, then that's right. Then that's pretty compelling against central state materialism. Right, but then if there's super spartan octopuses. That would not be so compelling, yes. I agree. Is anybody following this? Does this make sense? OK, OK, I have just checking. But with the super spartans, I am playing one argument that the mental state can be had independently of what behavior you're exhibiting. But really, to anchor that, you'd expect there to be some commonality between the brain of the super spartan and the brain of the regular person. And then with the octopus, we say the octopus could be exhibiting pain, even though it doesn't have any brain state like yours or mine. But naturally, you'd think, well, that consists of the octopus displaying some kind of pain like behavior, showing distress or avoidance or something like that. But then if you put these two together, yes. So you have the super spartan octopus. You have the hypothesis of something that is feeling pain, though there is no brain state in common with the regular persons. And no behavior in common with the regular persons either. And at that point, you might really wonder how is the imagination being corralled here? If my imagination can just run free and project pain onto anything independently of its behavior or brain state, then what constitutes me getting a right or wrong in ascribing imaginatively pains to anything? Exactly. Right. Good. OK. That's what I thought the question was. Right. Exactly. I could say, look at this. Agony. It's an agony, right? You can imagine how we understand that, right? Imagine being kind of square and black like that and feeling great pain, right? Yeah. You know how that would be kind of squarish. Plasticate. Yeah. So it's natural to wonder if things aren't going too far with these. Each one is plausible on its own. But stack them together and you think, don't we do something going wrong here? Yeah? Yeah? OK. So there is another way of restating the main point, though. What is the relation between the imaginative understanding of something and the objective knowledge of it? Because the question says, mustn't your imaginative understanding of something be grounded in your objective knowledge of some aspect of it, whether it's its behavior or its brain state or something like that? If you say the imagination is one thing, the objective understanding is another, and these are just distinct, then you've no idea left as to what the controls are on your exercise of the imagination. Yes, so the idea that this thing has pain, it makes just as much sense as anything else. So there's got to be a connection. Yeah? What is the connection? Anyone? Well, I have a hypothesis, but I think this is really difficult, right? I mean, I think this is really the main difficulty we've been pressing are in different ways all the way through. But I think I'll come to this right at the end, but I think the connection must be something to do with the idea of causation, that an imaginative understanding of someone always involves some causal understanding of them. An objective understanding of the thing as a physical system is how you get at what's causing what. I think it's with the notion of causation that these two things are connected. But we'll say more about this. OK, so there was dualism, behaviorism, central state materialism, and functionalism. Yes, right. Functionalism is not the brain state itself that matters. It's the functional role so that with the octopus is not, whether it has C-fibers or not, that's the key thing, is whether it has some internal state that is wired up to the rest of its internal states and to its behavior in the way that C-fibers are wired up to the rest of our internal states and our behavior. If you've got something that's wired up to the rest of the system in the way that our C-fibers are, then you've got something that fuels pain. That's what the functionalist says. So the idea there is that psychological variables, terms like pain, hunger, want, yearning, all that stuff, these are like the symbols of a wiring diagram. They give you a kind of abstract understanding of how human beings are all wired up. So how do you characterize a system functionally? Remember our old friend, S2? Right, how do you give a full functional characterization of S2? You give a big list of all the possible inputs to S2. For each possible input, you say what state the system goes into after S2 on being given that input. And for each input, you say what output S2 gives for that input. Yep, you do that for every single possible input. And then you're fully characterized S2. So describing someone psychologically is describing their functional characteristics, how to push their buttons. And that, I think, is very plausible for moods, like whether someone is cheerful, grumpy, stuff like that. You'll describe what kinds of inputs you're going to get, outputs you're going to get, with what kinds of inputs. What were the problems for functionalism? OK, two main problems for functionalism class, absent qualia and inverted qualia. Boy, that was gratifying. Very good. Absent qualia and inverted qualia. And you remember, inverted qualia. Actually, I can't wait to do this. But let's do absent qualia first. But absent qualia, what does that mean? Examples? Blockhead, very good. Yeah. Blockhead, OK, you could have this robot with millions of people in it that is wired up, just like you or me. But it doesn't have any qualia at all, any conscious states at all. And the idea there is that you could, you'd imagine it of, there's no such thing as having an imaginative understanding of blockhead. You can't, it makes no sense to be trying to imagine blockhead from the inside. But it's still functionally, just like you or me. Or with inverted qualia, there we are. Your experiences when you look at the campanile might be the same as what I get when I look at that. My experiences when I look at the campanile might be, how should I put this? Like what you get when you look at that. I don't think I did that, right? You see what I mean? Your color experiences, my color experiences, might be round the other way from each other in just the way that these two are round the other way from each other. But we'd be wired up functionally exactly the same. So what that seems to be saying is that an imaginative understanding of someone else goes beyond a merely functional understanding. There's something richer about an imaginative understanding of someone else. If to say that I grasp, I know what your functional states are, leaves it neutral as to whether your color experiences are like this or like this. Either way, you're functionally just the same. So my imaginative understanding of you goes further than the functional understanding in that it fills in that gap. It lets you know whether it's round this way or round the other way. OK? Yes? Colorblindness for inverted qualia? No, I don't get that. It's an interesting, it's a really interesting topic, colorblindness. But I don't see how, I don't see exactly. Well, with inverted qualia, the functional role is exactly the same, yeah? Whether the spectrum's round one way for me or round the other way for me, yeah? With colorblindness, the functional role is not the same because if I say, if I can't distinguish between this shade here and a red patch, then that's going to show up functionally. I mean, if there is a fire trunk in front of the tree, then for someone with regular color vision, that will show up immediately, the fire truck in front of the tree. But if I'm really red-green colorblind, that's going to be harder for me to spot, yeah? Well, there are really interesting and delicate questions here. The natural interpretation of colorblindness, I mean, by natural here, I just mean, this might be just a kind of mistake that anyone might make on thinking about colorblindness. But the natural way to think about colorblindness is there's a kind of zone of indifference that if I look at, unfortunately, I don't have a picture of a fire truck here, but OK. If I'm looking at, I suppose I'm red-green colorblind, the natural reading is if I'm looking at the fire truck and I'm looking at a tree, I'm getting exactly the same qualia, yeah? Whether these are the same as a regular person's red qualia or the same as a regular person's green qualia is very hard to know, yeah? But they're the same anyway. That's a natural interpretation of colorblindness. Does that make sense? Yeah? OK, I just want to mention this because I think it's intrinsically interesting. There's a philosopher at Brown, Justin Brooks, who actually is red-green colorblind and has worked extensively in color. And Justin claims that it's not actually that the qualia are just the same when you look at something red as when you look at something green for a colorblind person. It's rather that it takes you a lot longer to distinguish whether it's red or green. The idea is, suppose you take a lump of coal and you ask, is that blue? You guys have seen coal, right? Coal? OK, OK. And you look at it and you say, is that blue or is it black? You really might not be sure. And so you look at it a while, you turn it around, you take it outside, you look at it in sunlight, and then you come to a decision as to whether it's blue or black. But it's a little bit difficult, right? It's a little bit tricky. Brooks's idea is, it's like that for a color person with a fire truck in the tree. You look at the fire truck in the tree and you say, are they the same shade or not? And you're really not sure. Now you look at it one way, now you look at it another way. Now you wait for the sun to come out from behind the clouds and get a slightly different take on it. And eventually you get it. No, they are different shades. The same way you or I might get it with a coal. Yeah, it actually has got a lot of blue in it. So these are different ways of thinking about the color qualia and color blindness. And they are very delicate and interesting questions. And even being color blind yourself does not actually mean that you find the issue easy as to what kind of qualia you're getting. Oh, of course. No, I remember now what you were saying. Thank you. Yeah. That's right. OK, OK, OK. Yeah, this is the need to rumor land point that, yeah, yeah. Absolutely. OK, of course I remember now what you're talking about. You're talking about people who have this double color blindness, where the red green pigments are both swapped around. So they are functionally just like you or me. And statistically there should be some, maybe in this very room, who have both kinds of color blindness and who are functionally just like you or me, but have the qualia swap around. Yeah, that was the case that you were remembering. OK, I didn't get that. But does that make sense now? Anything else on color blindness, inverted spectra, functionalism? OK, but I think that my interpretation is that it's something about imagination going beyond what any of these objective analyses of the mind are offering. OK, so that's how imagination seems to me to be a thread running through everything in the first couple of units of the class. Yeah? OK. I also think that imagination runs through the discussion of personal identity. I think Locke's discussion, if any of you guys got round to looking at Locke in detail, there's something really evocative about Locke's discussion and hard to pin down, which is why it's still worth reading today. But here's a fairly long quote from Locke. Consciousness always accompanies thinking, and is that which makes everyone to be what he calls self and thereby distinguishes himself from all other thinking beings. In this alone consists personal identity, i.e., the sameness of a rational being. And as far as this consciousness can be extended backwards to any past action or thought, so far reaches the identity of that person. It is the same self now it was then, and is by the same self with its present one that now reflects on it that that action was done. So there's the idea there, it seems to me, of reaching back imaginatively to the interior of your past self. And if you think about it forwards to your own survival, reaching forwards imaginatively into your own future mental life from the inside. Now, when we were developing how a memory account of personal identity want, it got a little bit complicated, right? There was a lot about quasi-memory and overlapping chains and so on. But I think there's something simpler here that Locke means. Suppose you're remembering back to some past event in your life. You can feel great pride or great shame about that, right? I mean, you think, God, that was me. And there's nothing complicated here about chains of memory or anything like that. You just reach back to that moment and right now you recognize the ownership of that past thing when you feel the pride or humiliation or whatever as to what was happening then. And similarly, for the future, if you are thinking about what's going to happen tomorrow or what's going to happen to you in a year, then you're reaching in imagination to that future thing directly. And we don't need to bother thinking about overlapping chains here. You're just reaching directly to that future state. I'm thinking, God, that is going to be so embarrassing if I have to do that or that will be so great if I can do that. There's something very special about your imaginative understanding of your own past or future states. So of course, you can imaginatively understand the mental life of anyone in the room or imaginatively understand the mental life of dead people, famous people right now, people you've never met but have read about. You can imaginatively engage with the mental lives of all these people. But there's something really special about the way you engage with your own past or future mental life. And that's something Williams talked about when he was talking about the Prince and the Cobbler kind of cases. And Williams said, when you've got these cases and you're not quite sure, is that going to be you that's getting tortured or is it going to be someone else that's getting tortured? You have a difficulty in thinking either projectively or non-projectively about the situation. And Williams doesn't really spell out very much what he means by projectively. But I think it's pretty clear that it's pretty evocative that you see what he's getting at that you want to know is that me there getting hammered down by thumb screws or is that me there being rewarded? And then if I'm the one in that situation, I, the pain has some special poignancy for my current projective imagining. If it's me, then if it's someone else, yeah? So there's that special kind of projection, that special kind of imaginative understanding you have of your own past or future mental life. So, summing up, there's that way, something here that Locke was getting at that seems to be exactly right is that your imaginative understanding of your own past or future position seems to be quite different to your imaginative understanding of someone else's mind. Yes? Right, okay. That's fair enough. It's not exactly that a colleague in imagination for the future might suggest that I'm just making it all up. I'm just saying what if, whereas I'm looking back, you might say, well, that's what really happened, yeah? But that's not actually quite the contrast I have in mind. I have in mind with memory, when you are reliving the past episode, yeah? You are getting it from the inside. You are remembering that moment when someone else ate your birthday cake or whatever it was and you remember the fury and indignation of that moment, yeah? You remember that from the inside. So, I'm calling that imaginative because you're getting it from the inside. You're recalling your own past perspective, yeah? And the thing is, you don't even seem to need memory for that if a parent tells you about what happened at your fifth birthday party, yeah? When someone else grabbed your cake, yeah? Then you needn't remember that, but you just visualize it from the inside and you think, God, I'm so mad at that person, yeah? Because you are reaching back to your own past and getting it from the inside. Memory kind of gives it to you from the inside for free, whereas if someone else tells you about it, you have to do a reconstruction, yeah? But it's still imagination in the sense that you're getting your own past perspective on it and it has that special poignancy that you're mad at what was done to you or proud of what you did or embarrassed by what you did. There's that special connection, yeah? Yeah, and that just seems to be run equally for past or future, yeah? Is that all making sense? Okay, and we're all completely at ease with problems about identity, okay? Okay, so yeah, this is just something I just said. That pride or regret or shame that you could feel about your connection with your own past life or that you might feel about concern or you might feel about your future pain, that is different to what you might feel for someone else. There might be, you might be very altruistic and actually care more about the other person than you do about yourself, but there is something different, some special concern that you have for yourself than you do for someone else. And the thing is, what is ambiguous about Locke's discussion when he talks about consciousness reaching backwards and forwards is that that consciousness reaching backwards and forwards so when someone says to you, that was you that did that or that will be you that this happens to, there seems to be some need for facts about your identity, facts about it being you that that's happening to that need to ground that exercise of the imagination. In a way, this was like the point about imagining the super spars and octopuses. You can't just freely imagine, Obama will get an Nobel Prize. Hey, that will be me. That makes no sense. You can't just freely imagine you being anyone you like and say that's me and feel that pride. There has to be some grounding in the objective facts and the talk about a memory criterion of identity really seems to belong there. Remember there was this argument about whether you have a memory criterion of identity or a biological or a bodily criterion of identity. Yeah? Well, that's where this comes in at a second level. And remember, quasi-memories, quasi-memories? Quasi-memories, yes. Okay, so the idea was define that notion of a quasi-memory say in terms of brain slides and then say something like you write, the later person is identical to the earlier person if the overwhelming majority of the later person's memory impressions, the quasi-memories are caused in the right kind of way by the earlier person's memory impressions. So the idea there, whether you have that kind of criterion of identity or you think of the identity of a person as the identity of a human being, that's something going beyond the facts about projective understanding. That's something that's to ground the facts about projective understanding. That's what makes it right for you to feel pride or shame as to what's going to be happening or had happened to this person back then or in the future. Does that make sense? So there's gonna be some basis for that projective understanding and that's the second way of understanding Locke's picture, the Locke's telling you about the basis, what makes it objectively right that you're this person or that person. And then what's the disorienting about fission cases is if you're told that you're going to fission, can you feel projective, can you have that projective understanding of what's going on up both sides of the fission? Put up your hand if you think the answer to that is yes. You could, there's a kind of projective, if you think of Williams as Prince and Cobbler cases and you're told this one's going to be tortured, yeah? And you can have that kind of projective understanding when you say, hey, that's me. That's awful. You can't do that. Yeah, I don't want that. Well, that's a projective understanding that you have one of the future people rather than the other in that case, yeah? Now, in a fission case, Parfit says it's just the same as ordinary survival. In fact, it's better than ordinary survival. So it looks as though you should be able to projectively look up, projectively identify with what's going on in the lefty branch and projectively identify with what's going on in the righty branch. If lefty does something especially good or especially embarrassing, then you should be feeling pride or shame as you look forward to that happening. If righty does something particularly good or particularly embarrassing, then you should right now, knowing that that's going to happen, let's suppose, be able to feel pride or shame as to what righty is doing. You should be able to feel that kind of projective pride or shame about both of them. Do you see what I mean? That's what it means, projective understanding of the future, up both branches. Can you put up your hand if you think, yes, that's fine, I can do that? Kind of. And put up your hand if you think, no, my mind just bulks at that. Yeah. Okay, that's very interesting. I think that's just about a dead heat. And if you just feel uncertain and if you don't know what the question means, that's a fair option. Okay, okay, okay. That is interesting. That is significant votes on both sides. I think that is genuinely what's puzzling. Sometimes I think, yeah, I can do that. And sometimes I think, no, I can't do that. It's very hard to know. Yeah? Any comments on that? Yes? Yes. Yes. Okay, that's not projective understanding in the sense I mean. Yeah, what I mean is just the sense of which, something that you yourself are going to do in the next couple of minutes, yeah, that you feel, the natural and reflective thing that you feel for that. According to Parfit, it seems like you should have that unrefectively, unproblematically, up both branches, not because of some thought about how specially connected they are to you in the way that you might with a child, but just because for all. Yeah, he doesn't put it in terms of imaginative understanding. That's why I think it's, that's why I find it helpful to recast this in terms of projective understanding, yeah. But I think if Parfit were to recast what he's saying in terms of projective understanding, that's what he'd have to say. Because, I mean, I think Williams's remark there. The key thing is the difficulty in thinking projectively or non-projectively about the situation in the Princeton-Cobbler case. That's also the key issue here, yeah. Because that's what we care about. That's what ties up to all the emotions that really matter to us. Now the thing is, suppose you say, it's just as the last questioner said, that I might feel that these are not, these aren't me, these are just offshoots of mine, kind of like children, not quite the same thing, but a little bit like children. If you think like that, if they're not me, then it is hard to see how your projective understanding could reach to both of them, because neither of them is me, yeah. If they both get in a fight, if they both have a contest, if they are both boxers, suppose you're a boxer, right? Suppose you're a great boxer and you fission, are you two offshoots, have a prize fight, yeah? And one of them drubs the other, one of them gives the other a humiliating beating to the gratification of boxing fans everywhere, right? So should you feel pride or should you feel humiliation? What's the right emotion? I mean, it's very hard to see how you can be feeling, but well, you can be feeling kind of mixed about what's gonna happen in the future, but it's really hard to see how you could be feeling both in this case. It's not that, actually I say it's not that there's some kind of moral ambiguity about what's going on, or if there is, that's not the relevant factor of the situation, yeah? It's that you don't know who to identify with, how can you identify with both of them? But then, as I said, with this kind of case, that projective understanding you feel for someone in the future, that needs to be grounded in something. There has to be something that's making it right for you to put all these emotions, that people feel, that's what drives people's lives, this kind of emotional connect with what you want for your future or past. I mean, if you say I have a dream that someday I'll do this, yeah? Then if you're told that someday someone else will do it, well, that's fine, that's just gone, but that's not what I wanted. What I wanted was that I should do that. That was what was driving all my plans, that was what was driving all this work. So it's got to be grounded, in fact, about identity. But then the problem is, what fission cases seem to show is that projective understanding seems to require identity, because it's got to be me. But then we're grounding it in something that doesn't really matter, like whether there's branching. When you say what grounds, whether I can identify with lefty or righty, then what grounds it is that there should be psychological connections, but no branching. But then I'm putting all this emotional wet onto there being no branching. And who cares about that? Why should I care about that? So that when I look for this ground, the projective, I mean, if you think about someone training for the Olympics, right, someone who puts in years and years of work, let's suppose that what drives them is that vision of being in the top of the podium, yeah? That's what's driving you. So that's a perfectly comprehensible motivation, and we usually think that's kind of noble, that's really well done, good for you, go for it. And if you think, well, what is driving all those years and years of work, all those 5 a.m. starts, that's a concern that you should be the one in the podium. So if you get fission, it's not going to count. If one of your offshoots gets onto the podium and the other one doesn't, well, it doesn't really matter, because neither of them is you. That's to say, you're putting in all this work on behalf of something that really doesn't matter, non-branching continuity, but you look at it coldly and objectively, why should anyone care about non-branching continuity? That seems completely irrational. So there's this kind of basic driving force that anyone who wants to do well under exams, anyone who wants to have a successful career or a good life or whatever, anyone who just has these kind of ambitions and is working for them, you're working for something that has to do with, in the end, the psychological connectedness of the person who's reaping those benefits and they're not having been any branching, but you pan back and you look at what it is that you care about so much and it's something that just doesn't matter. How can that be? That's really destabilizing. There's such a basic motivator, that concern with identity, but when you analyze what identity is, it has this thing about not branching that shouldn't be important. So we're really finding our most basic, effective concerns on something that doesn't count. Yeah? Existentialism. Yes, that's right, you're just making a leap into something, you're doing something completely irrational. It's very hard to accept that that's a, that's a very unsatisfying picture of what's going on. It is about the most uncomfortable picture you could have. Yeah, I think there are these imp, someone's once said to a friend of mine, you can't really believe that when you're dead, that's just it, yeah? That just doesn't make sense. You can't really believe that when you die, that's just it, yeah? And I think I can feel the force of that, yeah? And that's one of the drivers that may people think there must be a soul. It's not that people think, oh well of course there's a soul, therefore it must exist after death, because souls are especially diamond like, souls like diamonds are forever. That's not the way people think. The way people think is, no I just can't make sense from the inside. I can't make sense if I have a projective understanding of the idea of just dying, and that's it. I mean how could you have a projective understanding of the light going out? Yeah, that makes no sense. So people say there must be something going on after bodily death, and they say therefore there must be a soul to ground that. But that is another example of the same phenomenon, that you have this projective thing that can be driving what you do your entire life, but when you pan back and look at it objectively, what do you think is really going on here, objectively? Then you can't justify it, yeah? And somehow we are used to that discomfort for death, if you see around people who do think that after death that's just it. Seals feel a kind of panic out of the thought of their own death, but it's a discomfort that we are used to. Parfit's thing is widening it a bit and saying your concern with the self is really always founded in something irrational. It needs a foundation. There have to be objective facts about the self to ground it, but there really are no objective facts about the self that will ground anything like our ordinary pattern of concern, our ordinary pattern of cares. Comfortable with it? You shouldn't be. You should be experiencing extreme spiritual unease if I put that correctly. But you see what I mean? Okay? Okay. So let me give one of our, there was something here about imagining that we touched on very briefly at the end of one lecture that I wanna spend a little bit more time on. Remember, what was it mean? Mary, that's right. Good old Mary. Black and white Mary stepping out into the world of color. Now, what does Mary learn when she steps out into the world of color? One way of thinking of it, Jackson's way of thinking of it is that she learns facts about the mind that she didn't have before. She learns facts about what is like to have color experience that she didn't know before. Yeah? That's a natural diagnosis. She gets the kind of imaginative capacity that she didn't have before. But if you remember, what I was saying in lecture, what we came up in discussion quite a bit is that when Mary steps out into the world of color, what she learns about in the first instance is not anything to do with people's mental lives at all. What she learns about is a characteristic of the objects around her. What she learns about is the greenness of the leaves, the redness of the roses, that kind of thing. So in the first instance, what Mary learns about is not a mental factor at all. What she learns about learns about is something about the world, the fact of color. Now, we had at the end of one lecture this example of a stage set. Does that ring any bells? Stage sets? Okay, it went by in a couple of hundred milliseconds, but I had this example of someone who's designing a stage set and thinking about how will this look from different parts of the auditorium? So say if I'm just thinking about a slide right now, if I'm making a slide and I'm thinking, how will that look from different parts of the room? How will that seem? Will that be too hard to read? Will that be too cluttered to really focus on anything? Then you can have a kind of imaginative understanding of how it's going to look, how that thing is going to look to someone out there. So suppose you're a painter, making a painting and you're saying, you're trying to imagine how that's going to seem to different viewers. Then what you've got here is an exercise of the imagination, but it depends on your knowledge of a bit of the world. You've got that physical thing there, the stage set or the slide on the screen, and your knowledge of what the other person is getting builds on your knowledge of what's there in the environment. So in these cases, your imaginative understanding of someone else depends on your knowledge of what's there in their environment. It depends on your knowledge of that physical structure, the set that you're building on the stage, or it depends on your knowledge of what the slide is or your knowledge of what the painting itself is. Once you've got what the painting itself is, now you can say, and how will that look from over there or how will the stage set look from over here? Now, what I suggest with Mary is that when she steps out into the world of color, what she gets is something like knowledge of the stage set. She gets knowledge of the environment that other people are occupying, and when she can now imagine someone else's color experience, that's like imagining the stage set from over here or from over there. The thing itself, the color in the world, is really essential to what's going on. So that notion of the color of the object is not a notion defined in terms of experience. It's a perfectly objective fact about the physical world that things have the colors they do. And Alex Burner, a philosopher at MIT, put it like this. He said, there really is no mind-body problem or hard problem of consciousness. The problem is really to reconcile that picture of the medium-sized world with lots of colors, people, smells, tests, and that world out there, how does that connect to the world as described by physics? I mean, if we go right back to the very first lecture and the very first slides I showed you, remember this flower with all its tremulous quivering beauty? Surely you remember the flower. Yeah. And I said, imagine being a medieval peasant staring at such a flower, drinking in this beauty. Then it doesn't occur to you that that thing has got anything to do with experience. It doesn't occur to you that that thing is made of atoms. You just take it for granted. The colors, the smells, the tests, the beauty, they're all out there in the medium-sized world waiting for you to encounter them. These are just as objective facts about the world as anything else, these facts about the medium-sized world. And then, when we experience a bit of the world, what that is is there's the flower out there, the chair out there, the people out there, and your conscious experience is just you taking on board a bit of the world, a bit of that world coming in to your consciousness. So, there's that completely objective flower with its color smashed and tail out. Tastes the smell out there and you encompass it with your mind. That's what it seems like before physics. Your visual experience is just you taking on board a bit of the objective world. So, if the colors and smells and tastes are out there and you see the flower and I see the flower, is there any problem of the inverted spectrum here? Could it be that you're having a different color experience to me? No, not in this picture, because the color, there's only one flower out here with just one color and you're taking on board the same bit of the world as I am. You're encompassing the same bit of the world as I am. So, you could fail to see it, but if you get any color at all, it's the same as the one I get, yeah? So, in this picture of the world, there is no puzzle about the inverted spectrum. Now, what physics did back in the 17th century when we generated the mind-body problem, was it said, no, what's going on out there is just the configuration of atoms. There are just the basic physical description of the world. So, this picture isn't right. What's going on is that the world described by basic physics is generating in you one kind of internal experience. And then, it may be generating in someone else a different kind of internal experience. And in other people, it might be generating no internal experience at all. So, we have the puzzle, how I know that what you're getting is the same as what I'm getting. We have that basic problem of other minds and we have the problem how these internal experiences relate to the world as described by physics, right? So, this is where the problem of the mind, the mind-body problem begins with asking how is this world generating internal experiences? How is this physical world generating internal experiences? So, in the physics picture, that's all that's really there and we're asking where does consciousness fit in? It doesn't seem to be part of the world of basic physics. But what I want to suggest is if you take my reading of the Mary story, then that was the wrong way to frame the question. We should not be asking, first of all, where does consciousness fit in? I mean, suppose we go back to you being a medieval peasant looking at this flower and then you're told, but all that's really here is particles, gluons, spectral reflectances. What is the basic question you should be asking? Is it a question about experience? No, it is not a question about experience. You should be asking a question about what the color of the thing has to do with basic physics and what did experience come in? You just look at, you're a medieval peasant. You're looking at the flower. You say, yeah, it has its color, smell, taste, beauty and then you have mathematical physics and mathematical physics tells you what's really in this space-time zone is these particle structures. And then your question should be so how do the colors and tastes relate to this particle structure? Yeah, that's got nothing to do with the mind. What happened back in the 17th century is that they framed it in this way and then that generated the mind-body problem and we wound up in this situation that we are in today of this completely hopeless problem, three centuries later, and people say, well, this is just a great mystery and thank you, physics, for discovering it. But really it's not obvious that the problem is being framed in the right way at all. The right question, once you're given the story that particle physics is all that's really there, why I think the fundamental problem is where this consciousness fair in? Why not say the fundamental problem is where do the colors fit in? If we could explain that, then we would be on our way to understanding how experience of those colors could be part of a physical world. Figure out how the colors relate to the physical world and then figuring out how our experience of the colors relates to the physical world will be relatively easy. I mean, there is going to be a hard color body question. If you take it that the colors are out there objectively, they are independent of you or me, then what do they have to do with the physical world? I mean, just as Descartes said, your knowledge of your existence is more certain than your knowledge of any physical thing. You could raise parallel questions about the colors. You could say, look, my knowledge of the colors of the objects around me is more certain than my knowledge of any physical structure. Or I can conceive of the colors without, you could conceive of the colors existing without any particular particle structure existing. So colors can't be identical to any particular particle structure. Or you could say, well, when I look at the physical structure of an object, it's very complex. If I look at the spectral reflectance of the surface of an object, that's very complex. Colors seem to have a kind of simplicity that the blueness of a blue thing has a kind of unity to it that a complex spectral reflectance curve doesn't seem to show. So matter seems to have a kind of structure that color doesn't. So it really is puzzling how can colors be part of the physical world? That's the color body problem. And surely that's more basic than the mind-body problem. That's the problem we should be addressing first. I mean, at the end of the day, when you're talking about how the brain relates to the mind, you've got at the end of the day to say there are different levels at which the world can be described. If there's really only one world and it's a physical world, then the mental just has got to be a higher level of description of the physical world. The puzzle is to understand how that can be so. But then if we're going to say there are different levels, we could have said that right back at the start when we were in the position of a medieval peasant greeting 17th century physics, we could have said, okay, so there are different levels at which the flower can be described or the level of describing it as having a color or a smell. And the question is how that level of description of the flower, nothing to do with the mind, how that level of description of the flower relates to the description of it given by physics. I mean, Alex Byrne actually does a wonderful tour de force explaining how the whole history of thinking about the implication of physics for our common sense picture of the world could have gone quite differently than it did. Physics is really destabilizing for our common sense picture of the world but the puzzle is to understand exactly what it's doing and exactly how to react to it. In one reaction would be to say we should be dualists about colors, nothing to do with the mind but just there are two different levels of description of the objective world and colors are just relating to a different plane of existence and talk about basic physics or you could be a behaviorist about colors and say for an object to have a particular color is just for it to behave in a particular way. It's just for it to produce particular kind of sensations in you or me or for it to interact in particular ways with other objects. And suppose you say that, suppose you say an object being colored is just a matter of attending to produce sensations in you and me, what would be the analog of a super Spartan objection to that? For something to be yellow, I make the following claim of a behaviorist about color, for something to be yellow is just for it to behave like a yellow thing that is to produce yellow sensations. So a super Spartan colored object would be one that really is yellow but doesn't produce yellow sensations in anyone. Right? Generations of breeding of these objects has made it, but the face of it, there could perfectly well be such an object. Suppose you had an object that was, suppose you have found that there's a special weakness in the human brain at a particular point, you've got an object with a particular shade of yellow that when a human sees that yellow, they don't get a yellow sensation. The thing just kills them. The thing just kills you stone dead because there is a weakness in the human brain at just that point. That could be, right? That's the analog of a super Spartan, yeah? Okay, so you can't be a behaviorist about colors. So you might say, well, it's having a particular, to be a behaviorist about, I want to be a physicalist about color, that's to say, having a particular color is just a matter of having a particular surface spectral reflectance. It's just a matter of having a particular physical property. But of course, the analogous objection there is variable realizability. I mean, couldn't there be colors that, two objects that are both red, but are quite different physical structures? And if you think about the sky and the sea, they are both blue, but I guess physically they are quite different, yeah? The sky and the sea. The chemically they're quite different, yes? So you could have variable realizability for the colors. So the kind of physicalism about the colors has got a lot of trouble going for it. So you might say, well, I'm going to be a functionalist about colors. Having a particular color is just a matter of being in a particular functional state. But then couldn't you have zombie colors? I mean, things that produce yellow sensations in you and me, all right? Even though they're not actually yellow, maybe they don't have any color at all, they just have this tendency to produce color sensations in you and me. So without trying to resolve that, there is a real color body problem and it's difficult to see how the colors are related to the physical world. But the problems about color are certainly no harder than the problems about the mind, yeah? And they have the great advantage that they're kind of framed in plain English. We're talking about using the ordinary color vocabulary and saying, how is yellowness and redness and so on related to a particular physical structure? It's an extra step to say that problem has to be solved by going by way of the mind body problem. And we don't really have to do that and it's not clear what advantage we get by doing that. So it seems to me the color body problem is something we should actually take as more basic than the mind body problem. And one great advantage of doing that is that we don't have any issues about the inverted spectrum. The mind stops being something hidden. And when you think about an imaginative understanding of other people's minds on this kind of picture, an imaginative understanding of other people's minds demands that you have the stage set to understand someone else's sensory experiences, what they're seeing as you look around the room. The basic thing you need is knowledge of what environment they're in, knowledge of what their surroundings are, and that gives you the platform on which you can construct an understanding of their internal mental states. Okay, so that's how we should reconfigure the mind body problem. Happy with that? Okay, I hope you understand that you should not be simply writing this down. Okay, okay. Well, one last set of questions about imaginative understanding. And I said earlier, a key question about imaginative understanding, when you've got, when you've put yourself into someone else's shoes, when you're thinking of the world from their point of view, is that causal understanding? Is that knowing what makes what happen? Can you put your hand up if you think the answer is yes? Actually, before we go on, I also want to know, what about that stuff about the color body problem being more basic than the mind body problem? Can you put your hand up if you think that is pretty persuasive? Can you put your hand up if you think you've never had anything so outrageous? Right, okay. Can you put your hand up if you think it's a pleasing idea, but you don't agree? Okay, very good. I would say that is slightly more for the people who say that's pretty persuasive than for the other two, but there are significant votes for everything else. Any comments? Okay. Okay, but imaginative understanding. I mean, it's really difficult to know how to articulate just what it is, imaginative understanding. The idea is clearly important, but is it causal understanding? Can you put up your hand if you think the answer is yes? Does, if I'm getting an imaginative take on your mental life, like that song, if you were gonna walk a mile in my shoes before you, what is it? Criticize, blame or accuse, yeah. Then is what I'm getting there an understanding of what makes what happen for you as a person? Is it getting an understanding of what causes what to happen with you? Put up your hand if you think the answer is yes. If you think the answer is no, and if you understand the question perfectly well, but you're not sure which way it goes. Yeah, my impression is in the history of this thing, the study of the imagine, thinking of these things in terms of imagination goes back, I guess, to Dilphi and Weber, and that whole tradition tended to think of imaginative understanding as not causal, something to be contrasted with causal understanding. And I really don't see how that can be right. When you're getting it, suppose that you're dealing with, we had this example before, of you're sitting as one adductor in a trial of someone who's accused of murder, and you're trying to put yourself into the shoes of the accused. You're trying to imagine just how the scene seemed to be accused at the point at which the killing happened, and you're asking what was in the heart of the accused? Was it revenge or was it self-defense? What drove the accused? That seems to be a really key part of your imaginative understanding of the accused. It must have to do with causation, it seems to me. When you're getting an imaginative understanding of someone else's mental life, you're getting to know what drives them, what the dynamics of their behavior are, and that's how it seems to me. As I say, there is this whole tradition that says this is not causal understanding, this is something to be contrasted with causal understanding, but I still think that's how we common senseically think of it. That's not how you'd think of it in a law trial, for example. But once you say this is causal understanding, then you are vulnerable to correction by science, because science might say to you, look, what makes human behavior happen is not any of this stuff about motives like revenge or defense. What makes human behavior happen is the underlying clockwork. So imagine it of understanding if it's causal can be corrected by science. And that was Huxley's point about the frog that science shows you that you could be going through all the same behaviors as you actually do go through in the absence of consciousness. And Nagel put his point as one about consciousness specifically, and when he was talking about bats, he was talking about conscious experience, sensory awareness, but in the face of it, this stuff about imaginative understanding applies to your beliefs and desires as well, knowing what someone wanted, knowing what they longed for, knowing what they thought was going on. These are ways of finding out about the drivers of their behavior, what makes what happen. But then, remember the LeBet experiments, where it seems like your conscious decision to push the button is happening after your brain has mobilized everything. Then imaginative understanding, if it's causal, well if it's not causal, it's hard to see why it's so important. It seems to be the basis for everything that matters in human life, that imaginative and empathetic understanding. But if it isn't causal, if it doesn't get at the springs of the human heart, the things that drive us to do what we do, then why would it matter so much? Why would it be so important? But once we say imaginative understanding, this driver of everything else that matters, that has to do with what causes what, then science might tell us the understanding we have of causes from imaginative understanding is wrong. We should instead shift to a purely objective study of the brain, if we want to know what's causing what. And in that bleak and wistful note, we'll stop for a term. Okay, there's no lecture on Thursday, that's it. Thank you guys, and thank you GSIs, that you have been very lucky in your GSIs, guys. All right.