WEBVTT - Ep140 "How does your brain decide what’s true?" with Sam Harris 0:00:05.320 --> 0:00:09.440 Why does changing your mind sometimes feel like losing a 0:00:09.520 --> 0:00:13.840 part of yourself. If beliefs are supposed to track truth, 0:00:14.400 --> 0:00:18.640 why do they so often track our tribe instead? Why 0:00:18.640 --> 0:00:22.919 does a challenged belief feel like a personal attack. What 0:00:23.079 --> 0:00:27.160 does your brain think it's defending when it defends an idea? 0:00:27.880 --> 0:00:31.720 What if beliefs didn't evolve to be true, but to 0:00:31.760 --> 0:00:37.560 be useful. What if your strongest convictions are solving social problems, 0:00:37.600 --> 0:00:41.760 not intellectual ones. Today we'll speak with public intellectual and 0:00:41.880 --> 0:00:50.800 neuroscientist Sam Harris about the topic of our beliefs. Welcome 0:00:50.800 --> 0:00:53.960 to Inner Cosmos with me David Eagleman. I'm a neuroscientist 0:00:54.040 --> 0:00:57.240 and author at Stanford, and in these episodes we sail 0:00:57.360 --> 0:01:00.920 deeply into our three pound universe to understand how we 0:01:01.000 --> 0:01:04.800 see the world and importantly today, what we take to 0:01:04.920 --> 0:01:21.560 be true about it. Your brain has a lot of 0:01:21.640 --> 0:01:25.920 beliefs about what is true or false. So if I 0:01:25.959 --> 0:01:29.720 ask you is Paris the capital of France, your brain 0:01:29.840 --> 0:01:34.080 immediately judges the truth value of that statement. Is it 0:01:34.480 --> 0:01:37.480 accurate or inaccurate? How about if I ask you is 0:01:37.640 --> 0:01:41.600 ten plus ten twenty one? Your brain has to take 0:01:41.600 --> 0:01:44.720 in the auditory information and compare it against what it 0:01:44.800 --> 0:01:48.520 knows and make a decision. And most people would probably 0:01:48.600 --> 0:01:52.200 agree with your judgments on these questions. But this can 0:01:52.240 --> 0:01:55.800 of course get more complex when it involves other kinds 0:01:55.880 --> 0:02:00.720 of beliefs, Like Mohammad was a holy proh fit chosen 0:02:00.760 --> 0:02:04.480 by Allah to deliver a message to humanity. Some people 0:02:04.520 --> 0:02:08.520 think that's a true statement, others think that's false, or 0:02:08.560 --> 0:02:14.120 the statement early abortion should be supported, or Trump is 0:02:14.360 --> 0:02:18.440 on balance a good president, or whatever. I'm not suggesting 0:02:18.480 --> 0:02:21.000 how you should evaluate these sentences. I'm just pointing out 0:02:21.040 --> 0:02:24.360 there are lots of sentences I can say that you 0:02:24.560 --> 0:02:29.239 might find true or false. So every moment of your life, 0:02:29.280 --> 0:02:33.600 your brain is making commitments. You're not necessarily announcing these 0:02:33.800 --> 0:02:37.160 or thinking about them consciously. They live under the hood. 0:02:37.639 --> 0:02:42.120 But these commitments shape what seems true, what feels threatening, 0:02:42.200 --> 0:02:46.520 what deserves attention, and what can be safely ignored. These 0:02:46.639 --> 0:02:50.400 commitments we have are what we call beliefs, and beliefs 0:02:50.760 --> 0:02:56.600 are how the brain turns information into action. In other words, 0:02:56.600 --> 0:03:01.360 they determine whether an utterance becomes something you respond to 0:03:02.240 --> 0:03:06.080 or something that fades into the background from the outside. 0:03:06.680 --> 0:03:10.040 Beliefs look like opinions, or positions, in other words, something 0:03:10.040 --> 0:03:13.720 you might argue about or align yourself with. But from 0:03:13.760 --> 0:03:19.160 the inside they feel fundamental, as in this is true, 0:03:19.840 --> 0:03:23.960 this is false. Collectively, your beliefs feel like the structure 0:03:24.080 --> 0:03:28.600 of reality itself. They build the backdrop against which your 0:03:28.639 --> 0:03:32.880 decisions make sense. Now, the puzzle that's always fascinated me 0:03:33.040 --> 0:03:36.640 is that intelligent people who are well informed often reach 0:03:37.160 --> 0:03:41.640 very different conclusions about their beliefs. So you have evidence 0:03:41.720 --> 0:03:45.520 that feels decisive to one person and that feels incomplete 0:03:45.600 --> 0:03:49.360 or unconvincing to another. And what that means is that 0:03:49.560 --> 0:03:54.400 changing one's mind typically feels really hard, and when you 0:03:54.480 --> 0:03:58.200 have a disagreement with someone, this can feel personal, like 0:03:58.280 --> 0:04:02.360 it involves your idea. So when we look at these patterns, 0:04:02.400 --> 0:04:05.720 we see that belief seems to be doing something more 0:04:06.200 --> 0:04:09.280 than building accurate models of the world. That might be 0:04:09.480 --> 0:04:13.320 part of why the brain builds true and false judgments, 0:04:13.560 --> 0:04:18.279 but there's probably more involved. For one, beliefs help coordinate 0:04:18.320 --> 0:04:23.479 your social life by supporting identity within your tribe and 0:04:23.640 --> 0:04:28.760 establishing alignment between people. Also, they can manage uncertainty by 0:04:28.800 --> 0:04:32.479 stabilizing emotion. When we look at it through these lenses, 0:04:32.600 --> 0:04:36.360 belief is, of course a biological process as much as 0:04:36.360 --> 0:04:41.120 a philosophical one. Somewhere between encountering a claim and acting 0:04:41.160 --> 0:04:44.200 on it, your brain has to perform a series of 0:04:44.240 --> 0:04:48.760 operations that determine whether some statements should be reacted to, 0:04:49.480 --> 0:04:51.960 or maybe whether it should be questioned or whether it 0:04:51.960 --> 0:04:56.320 should be dismissed entirely. Whatever your brain decides on the 0:04:56.480 --> 0:05:01.240 truth value of the statement, that shapes what you do next. 0:05:01.279 --> 0:05:04.360 And all of this tends to run below the radar 0:05:04.520 --> 0:05:09.000 of conscious awareness. Now, understanding what the brain is doing 0:05:09.040 --> 0:05:13.479 with beliefs is massively important because what you believe to 0:05:13.600 --> 0:05:18.560 be true and not true determines everything about cooperation or conflict. 0:05:19.000 --> 0:05:21.760 And so this sits right at the center of all 0:05:21.839 --> 0:05:26.800 that's happening in politics, in moral judgments, in social trust. 0:05:27.400 --> 0:05:29.520 So I focus a lot of my episodes on these 0:05:29.600 --> 0:05:34.360 issues about polarization and in groups and out groups and shibbleeths. 0:05:34.800 --> 0:05:38.080 But today I want to move upstream a level and 0:05:38.120 --> 0:05:42.119 focus on the machinery beneath them. How does the brain 0:05:42.200 --> 0:05:47.120 decide what to accept as true? How do emotion and 0:05:47.279 --> 0:05:52.800 identity in social context shape what feels credible? And there's 0:05:52.800 --> 0:05:56.120 no one better to explore these questions with than Sam Harris, 0:05:56.120 --> 0:06:00.120 whose work has examined belief from inside the brain and 0:06:01.120 --> 0:06:05.960 within public discourse. Sam is a public intellectual, a philosopher 0:06:06.040 --> 0:06:10.120 and author, and also a neuroscientist. He's well known for 0:06:10.160 --> 0:06:15.360 his writings on rationality, religion, ethics, free will, and meditation. 0:06:15.880 --> 0:06:19.760 He has long researched how science can inform human values 0:06:19.839 --> 0:06:23.480 with books like The End of Faith and The Moral Landscape. 0:06:23.800 --> 0:06:27.760 He hosts the Making Sense podcast, which focuses on consciousness 0:06:27.800 --> 0:06:30.280 and society and current events. So today we're going to 0:06:30.360 --> 0:06:34.200 ask what are beliefs really about. Here's my conversation with 0:06:34.240 --> 0:06:40.479 Sam Harris. So, Sam, I want to talk with you 0:06:40.480 --> 0:06:44.920 about belief. Many years ago you did neuroimaging studies on belief, 0:06:45.000 --> 0:06:48.640 So let's start there. Tell us how you think about 0:06:48.760 --> 0:06:50.640 belief and how you measure that in the brain. 0:06:50.920 --> 0:06:55.040 Believing things to be true of als versus being uncertain. 0:06:56.200 --> 0:06:59.719 This is something that our brains do readily, right, This 0:06:59.760 --> 0:07:02.520 is largely This is what distinguishes us, certainly when we're 0:07:02.520 --> 0:07:05.760 talking about complex representations of the world. This distinguishes us 0:07:05.800 --> 0:07:09.640 from our closest primate cousins. I wouldn't say that that 0:07:09.680 --> 0:07:12.960 other mammals and certainly, you know, the other primates don't 0:07:12.960 --> 0:07:16.640 have beliefs because clearly they represent states of the world cognitively, 0:07:16.680 --> 0:07:19.360 and they have expectations on that basis. 0:07:19.160 --> 0:07:20.600 Like there'll be grubs under this rock. 0:07:20.720 --> 0:07:23.480 Yeah, so they've got, you know, goal seeking behavior, and 0:07:23.480 --> 0:07:25.960 that those goals are framed by some expectation of the 0:07:26.000 --> 0:07:29.000 way the world is, and they can be surprised by 0:07:29.000 --> 0:07:32.320 different outcomes. But we're the only species that were we 0:07:32.360 --> 0:07:36.000 know of that trades in these linguistic representations of the world. 0:07:36.600 --> 0:07:41.640 It can be completely divorced from any sensory entanglement with 0:07:41.680 --> 0:07:43.720 the state of the world that is being described. I mean, 0:07:43.760 --> 0:07:46.000 you get a cell phone call and there's a voice 0:07:46.000 --> 0:07:48.160 on the other end of the line and it says, 0:07:48.720 --> 0:07:51.000 you know, we've got your daughter and you got to 0:07:51.000 --> 0:07:53.280 come up with a million dollars to get her back. Now, 0:07:53.560 --> 0:07:56.640 if believed all of a sudden, those you know, small 0:07:56.680 --> 0:08:00.440 mouth noises that came you know through the phone, deletely 0:08:00.480 --> 0:08:03.480 common deer or you know, physiology, your whole world is 0:08:03.800 --> 0:08:05.960 all of a sudden about that, you know, kind of 0:08:05.960 --> 0:08:09.160 bent into the shape of the implications of of that 0:08:09.360 --> 0:08:11.680 you know utterance. Whereas if it's the wrong number. If 0:08:11.680 --> 0:08:13.160 you don't, I don't have a daughter, I know what 0:08:13.160 --> 0:08:15.160 you're talking about, right, just it bounces off, it doesn't, 0:08:15.160 --> 0:08:18.160 it doesn't, it doesn't become behaviorally or emotionally actionable. So 0:08:18.800 --> 0:08:25.760 it was this difference between this fairly gossamer representation of 0:08:25.800 --> 0:08:28.600 the world that that that it's just a piece of 0:08:28.680 --> 0:08:31.320 language right in the mind. It could be your own thought, 0:08:31.360 --> 0:08:33.160 it could be the thought of others you're communicated to you, 0:08:33.240 --> 0:08:34.920 it could be something you read on on the you know, 0:08:34.960 --> 0:08:37.439 the front page of a newspapers. It was it was 0:08:37.480 --> 0:08:40.880 a transition from that just the mere, mere decoding of 0:08:40.960 --> 0:08:44.760 a piece of language, to suddenly finding it not only 0:08:44.760 --> 0:08:48.400 behaviorally actionable, but you know, you know, unthinkable not to 0:08:48.440 --> 0:08:51.839 be motivated by those by those you know phonemes. So 0:08:51.840 --> 0:08:54.160 there's clearly, you know, steps in the chain where you 0:08:54.160 --> 0:08:57.400 you you you parse language or parse a statement and 0:08:57.600 --> 0:09:03.240 understand its meaning, and then there's this secondary operation of 0:09:03.760 --> 0:09:06.720 judging it to be true or false, right, or or 0:09:06.760 --> 0:09:09.200 just deciding that you can't judge it one or the other. 0:09:10.240 --> 0:09:14.360 And it seemed to me that on some level, this 0:09:14.440 --> 0:09:16.200 is the most important thing in the world, right, I mean, 0:09:16.200 --> 0:09:18.280 if you're talking about the power of ideas. You first 0:09:18.360 --> 0:09:23.160 have to stand upstream of that claim to talk about 0:09:23.720 --> 0:09:27.720 the difference between believing or disbelieving, accepting or rejecting certain 0:09:27.760 --> 0:09:31.000 ideas right and so, and ideas are obviously everything in 0:09:31.280 --> 0:09:35.080 our lives. I mean, it's it's how we're making a civilization, 0:09:35.200 --> 0:09:39.760 is how we're failing to secure a civilization. It's how 0:09:39.760 --> 0:09:42.760 we're needlessly producing harm for for ourselves and others. I mean, 0:09:42.800 --> 0:09:46.480 it's just it's it's belief. Is claims to knowledge you 0:09:46.520 --> 0:09:49.160 know true or otherwise? Are everything? 0:09:49.240 --> 0:09:49.320 Right? 0:09:49.360 --> 0:09:51.920 And so the question in my mind is what was 0:09:51.960 --> 0:09:56.040 the brain doing to find something behaviorally actionable or to 0:09:56.080 --> 0:09:59.559 find it not based on accepting or rejecting a claim 0:09:59.600 --> 0:10:00.720 to knowledge about the world. 0:10:01.040 --> 0:10:03.200 And so that's binary. But you also looked. 0:10:03.000 --> 0:10:05.520 At uncertain certainty as a third condition. 0:10:05.720 --> 0:10:08.840 But just so I'm clear, was uncertainty the I just 0:10:08.840 --> 0:10:09.880 don't know one way or the other. 0:10:10.160 --> 0:10:13.240 Yeah, okay, And you clearly, I mean, like you clearly 0:10:13.240 --> 0:10:16.400 couldn't know. So if you know a question that would 0:10:16.400 --> 0:10:20.560 provoke that would be to give someone some gigantic number 0:10:20.600 --> 0:10:23.319 and say that this number is prime. Right, It might 0:10:23.360 --> 0:10:25.160 be prime ends in a one, it might be prime. 0:10:25.240 --> 0:10:28.920 But obviously I don't know, or I have an you know, 0:10:28.960 --> 0:10:31.400 you have an even number of hairs on your body, right, 0:10:31.960 --> 0:10:34.440 you know you presumably you don't know, and so you 0:10:34.440 --> 0:10:36.240 can you can come up with lists of statements that 0:10:36.280 --> 0:10:40.559 are just as easy to decode as any other statements. 0:10:41.160 --> 0:10:43.240 But what you come up against, you know, once you 0:10:43.400 --> 0:10:45.760 understand them, is that there's really no way for you 0:10:45.840 --> 0:10:47.280 to know what's true. 0:10:47.480 --> 0:10:50.480 Got it, So you've got I either believe this to 0:10:50.520 --> 0:10:52.400 be true some state, give me an example of what 0:10:52.400 --> 0:10:52.679 you used. 0:10:52.800 --> 0:10:59.280 My hypothesis was that belief, disbelief, and uncertainty were content 0:10:59.360 --> 0:11:02.200 independent operations of the mind and therefore of the brain. 0:11:02.280 --> 0:11:03.800 So that if I gave you a statement like two 0:11:03.800 --> 0:11:06.840 plus two equals four versus two plus two equals five, 0:11:08.600 --> 0:11:13.960 and those are those are parsed and analyzed very similarly. Right, 0:11:14.000 --> 0:11:16.960 you're just just however, you understand arithmetic at the level 0:11:16.960 --> 0:11:19.760 of the brain. You're doing that, but you're coming to 0:11:19.800 --> 0:11:24.480 the opposite conclusion based on those two examples. But the 0:11:24.559 --> 0:11:28.880 hypothesis was that if we interrogated many different streams of 0:11:29.280 --> 0:11:37.079 knowledge and belief formation, so mathematical, logical, autobiographical, religious, political, right, say, 0:11:36.960 --> 0:11:41.080 the ethical the cognitive and you know, neuro physiological operations 0:11:41.120 --> 0:11:44.679 required to parse and judge that the truth value of 0:11:44.679 --> 0:11:46.400 any of those statements had to be very very different. 0:11:46.400 --> 0:11:48.760 I mean, what you're doing for arithmetic is not the 0:11:48.760 --> 0:11:52.120 same as what you're doing for for religion presumably, or ethics, 0:11:52.720 --> 0:11:57.079 or you know, you know, episodic memories. Say, but there 0:11:57.160 --> 0:11:59.800 was this final there had to be a bottleneck with 0:12:00.000 --> 0:12:05.439 which reported acceptance or rejection of the statement or uncertainty. 0:12:05.559 --> 0:12:07.560 Great, and so you put people in the scanner and 0:12:07.600 --> 0:12:08.240 what did you find. 0:12:09.120 --> 0:12:12.360 Well, we found that accepting a statement to be true 0:12:13.160 --> 0:12:17.880 versus rejecting it as false did report a kind of 0:12:17.880 --> 0:12:22.679 content agnostic you know, subsequent operation. One thing that was interesting, though, 0:12:22.679 --> 0:12:26.960 is that, and this actually goes back many many centuries 0:12:27.080 --> 0:12:32.800 to the work of Spinoza. Spinosa hypothesized that merely understanding 0:12:32.960 --> 0:12:36.560 a statement was akin to accepting it. Like it's like 0:12:36.600 --> 0:12:38.440 in order to just if I give you, if I 0:12:38.480 --> 0:12:41.200 give you just any utterance that you you know, any 0:12:41.200 --> 0:12:45.600 claim about the world that you can parse. Merely kind 0:12:45.600 --> 0:12:48.080 of getting to the end of the sentence and understanding 0:12:48.120 --> 0:12:51.040 it puts you in a in a mode of cain 0:12:51.200 --> 0:12:54.920 tacitly accepting it to be true and rejecting it as 0:12:54.960 --> 0:12:57.840 false was a subsequent operation. And one thing you would 0:12:57.840 --> 0:13:00.760 expect if that, in fact were true, is that behaviorally 0:13:01.559 --> 0:13:04.520 false statements would be people would be slower to judge 0:13:04.559 --> 0:13:08.720 false statements of equal complexity than to true statements. And 0:13:08.760 --> 0:13:10.520 we found that. So you get people a statement like 0:13:10.520 --> 0:13:13.839 two plus two equals five, they're slower to say no, 0:13:13.960 --> 0:13:17.440 that's false than two plus two equals four is true. 0:13:17.480 --> 0:13:19.880 I mean that that was a it was a fairly 0:13:19.920 --> 0:13:24.240 significant behavioral difference. But in any case, the. 0:13:25.200 --> 0:13:27.319 We let me, let me dive into that for a second. 0:13:27.679 --> 0:13:32.760 Does that mean that hearing other perspectives, being exposed to 0:13:32.800 --> 0:13:35.800 other perspectives, which you think, well, that's false, But at 0:13:35.880 --> 0:13:39.640 least you've spent that moment standing in that person's truth 0:13:40.280 --> 0:13:43.360 for a moment. So, for example, with political debates, you know, 0:13:43.360 --> 0:13:44.560 one of the things that I think is the most 0:13:44.600 --> 0:13:47.880 important for students is to, you know, get a three 0:13:47.960 --> 0:13:51.200 sixty view of the arguments, to debate from both sides, 0:13:51.280 --> 0:13:54.160 and be ready to do that. When we were in school, 0:13:54.200 --> 0:13:57.520 I think, I don't know if this is retrospective romanticization, 0:13:57.600 --> 0:13:59.760 but I believe that was more common. You would you 0:13:59.760 --> 0:14:02.440 would come into a debate ready to do either side, 0:14:03.120 --> 0:14:06.280 and therefore you knew the issues and the nuance is 0:14:06.320 --> 0:14:10.360 slightly better than let's say a kid who's in college 0:14:10.360 --> 0:14:12.200 who thinks, sorry, this is the truth and I'm not 0:14:12.280 --> 0:14:15.000 going to entertain another hypothesis. Just based on what you said, 0:14:15.040 --> 0:14:18.280 it seems to me interesting that if you're told another perspective, 0:14:18.320 --> 0:14:20.240 you at least stand in that truth for a moment 0:14:21.200 --> 0:14:23.000 before rejecting it, which might be useful. 0:14:23.240 --> 0:14:28.760 Yeah, although it does actually connect with other non normative biases, 0:14:28.800 --> 0:14:32.880 where it's something called Obviously, we have a replication crisis 0:14:32.920 --> 0:14:36.800 in much of this psychological science, so I don't know 0:14:36.800 --> 0:14:39.440 if this work has been replicated. But at the time, 0:14:39.480 --> 0:14:42.520 there was something called the illusory truth effect, where you 0:14:43.480 --> 0:14:46.760 merely being told something. 0:14:46.640 --> 0:14:51.080 Several times so you're more likely to believe it. 0:14:51.000 --> 0:14:52.480 Even in the act of debunking it. 0:14:52.520 --> 0:14:54.240 So if I tell you that a certain thing was 0:14:54.520 --> 0:14:56.760 thought to be true, but in fact it's not true, 0:14:57.360 --> 0:15:00.840 there's a kind of memory distortion bias where just you know, 0:15:01.080 --> 0:15:02.920 a year from now, if I ask you about that thing, 0:15:03.600 --> 0:15:05.960 there's this reliable bias in the direction of, oh, yeah, 0:15:05.960 --> 0:15:08.000 that was that was true, right, but you sort of 0:15:08.040 --> 0:15:11.160 the debunking, and this is why misinformation can be so 0:15:12.160 --> 0:15:15.200 pernicious and difficult to debunk. And again I bracket this 0:15:15.520 --> 0:15:18.360 with not knowing whether or not I am now spreading misinformation, 0:15:18.560 --> 0:15:21.000 because I don't know if this is washed out. 0:15:21.040 --> 0:15:24.160 I've certainly heard the misery truth effect many times, so 0:15:24.200 --> 0:15:26.960 now it's stuck in me as the truth. Ye fine, 0:15:27.120 --> 0:15:31.160 So okay, So coming back to this then, so Spinoza said, 0:15:31.920 --> 0:15:33.880 you know, you have to evaluate something as though it's 0:15:34.160 --> 0:15:36.360 stand in that space for a moment before you make 0:15:36.400 --> 0:15:38.000 your decision that that's actually false. 0:15:38.360 --> 0:15:38.720 Yeah. 0:15:39.400 --> 0:15:44.160 So the reporter of that in our study was mostly 0:15:44.560 --> 0:15:47.240 activity in the anterior insula, which is, as you know, 0:15:47.280 --> 0:15:52.880 the insula is the cortical structure that that is, you know, 0:15:54.560 --> 0:15:57.680 very focused on in terror reception. And it's just the 0:15:57.760 --> 0:16:01.120 kind of the states of the body are being evaluated 0:16:01.160 --> 0:16:05.560 here and discussed. I mean, the discussed literature suggests that 0:16:05.560 --> 0:16:09.280 it's mostly driven by the insula, and it's and so 0:16:09.320 --> 0:16:12.760 that this was somehow unsurprising to us because it does 0:16:12.800 --> 0:16:15.520 seem I mean, I think just you can get in 0:16:15.560 --> 0:16:19.600 touch with this in the first person subjective way, there 0:16:19.680 --> 0:16:24.320 is something to reject a proposition as false feels a 0:16:24.320 --> 0:16:26.120 certain way. I mean, it is a kind of emotion, 0:16:26.200 --> 0:16:31.080 it's a psychological rejection state. And if it's emphatically false, 0:16:31.400 --> 0:16:34.520 certainly on a topic you care about, there's really just 0:16:34.720 --> 0:16:37.560 to put that on. The continuum of disgust was not 0:16:37.640 --> 0:16:42.000 at all surprising, right, And conversely, true statements were evaluated 0:16:42.000 --> 0:16:47.760 with the same kind of positively valanced reward structures that 0:16:47.800 --> 0:16:51.560 we know about in the frontal midline area of the brain. 0:16:53.160 --> 0:16:57.480 And this might be surprising to people who haven't thought 0:16:57.480 --> 0:17:00.920 about neuroscience very much, but generally speaking, we know that 0:17:01.480 --> 0:17:05.959 all of our acts of higher cognition are are leveraged 0:17:06.040 --> 0:17:08.680 from areas of you know, areas of the brain which 0:17:08.720 --> 0:17:11.280 were not designed merely for that for that, you know, 0:17:11.359 --> 0:17:14.400 not designed by evolution merely to support that higher cognition. 0:17:14.720 --> 0:17:16.639 So clearly you have to do math and language and 0:17:16.680 --> 0:17:21.040 neuroscience and everything else that only humans do using these 0:17:21.040 --> 0:17:24.280 structures that that you know, even our chimp cousins have. 0:17:25.760 --> 0:17:28.880 So when you hear something false, activates some sense of disgust, 0:17:28.920 --> 0:17:31.480 and use something true, it's beautiful and rewarding. 0:17:31.840 --> 0:17:33.800 And there was one other piece that the and this 0:17:33.840 --> 0:17:36.080 came in a subsequent study when we were looking at 0:17:36.840 --> 0:17:41.560 political versus and religious versus, just kind of semantic ordinary, 0:17:41.800 --> 0:17:44.960 more ordinary beliefs. We found that beliefs that there was 0:17:45.000 --> 0:17:46.880 there was a subsequent study where we which I ran 0:17:46.920 --> 0:17:52.200 with Jonas Kaplan at USC He's over in Demasio's lab, 0:17:53.240 --> 0:17:57.680 where we tried to in real time push back against 0:17:57.680 --> 0:17:59.960 people strongly held beliefs while they were in this skin. 0:18:00.240 --> 0:18:02.760 So we'd present them with a proposition which we we 0:18:02.840 --> 0:18:06.720 knew in advance that that you know, some subjects would 0:18:06.840 --> 0:18:09.320 strongly believe someone's strongly disbelieve, and we'd try to push 0:18:09.400 --> 0:18:13.760 their beliefs in the opposite direction, giving them fairly persuasive, 0:18:13.760 --> 0:18:16.240 but still in many cases kind of just sham evidence. 0:18:16.320 --> 0:18:16.439 Right. 0:18:16.560 --> 0:18:18.240 So like he's like someone who would be put in 0:18:18.280 --> 0:18:20.159 the scanner and we would we would ask them to 0:18:20.200 --> 0:18:23.679 rate on a scale of one to seven their confidence 0:18:23.720 --> 0:18:28.040 that secondhand smoke is a significant health concern, right, and 0:18:28.080 --> 0:18:30.399 then we would present I think in this case it 0:18:30.440 --> 0:18:33.600 was sham evidence against that conviction, seeing if we could 0:18:33.640 --> 0:18:37.720 knock get back. And but we did this for beliefs 0:18:37.800 --> 0:18:41.560 that would be nonetheless strongly held, but around which we 0:18:41.600 --> 0:18:45.840 wouldn't expect someone's identity to be really anchored versus beliefs 0:18:45.880 --> 0:18:48.040 that were you know, political or religious, where they you 0:18:48.040 --> 0:18:50.920 would imagine that would be more resistant to to revising 0:18:50.960 --> 0:18:55.320 their opinion whatever your evidence, right, And we found that 0:18:56.960 --> 0:19:00.919 areas in again midline, but now in the posterior regions 0:19:00.920 --> 0:19:04.359 of the brain, you know, kind of classically kind of 0:19:04.359 --> 0:19:12.240 default mode network areas were preferentially upregulated there where and 0:19:12.280 --> 0:19:15.480 some of these areas are and there's other work showing 0:19:15.520 --> 0:19:20.800 that they when people are given stimuli that that are 0:19:20.840 --> 0:19:23.879 interrogating self representation itself, like if you I give you 0:19:23.880 --> 0:19:25.479 a list of words and ask you which of these 0:19:25.520 --> 0:19:27.640 words apply it to you? You know, we're like patient 0:19:28.040 --> 0:19:31.879 or kind or anxious or and then people are if 0:19:31.920 --> 0:19:35.480 the if the if the task is is this me right? 0:19:35.600 --> 0:19:39.960 That's this this the same region that gets activated. So 0:19:40.880 --> 0:19:43.400 you know, at least in that experiment, we we did 0:19:43.840 --> 0:19:48.159 produce some evidence that beliefs were people were resistant to 0:19:48.280 --> 0:19:51.359 modifying their beliefs no matter what the counter evidence was, 0:19:51.840 --> 0:19:54.560 where the were of a sort that seemed to be 0:19:54.600 --> 0:19:58.760 invoking kind of the self referential uh processing. 0:19:59.000 --> 0:20:01.760 So beliefs are tied to identity. 0:20:01.800 --> 0:20:04.040 Not not all but such like like again there's there's 0:20:04.080 --> 0:20:06.359 there were two buckets. Some could be strongly held. But 0:20:07.000 --> 0:20:09.719 you know, presumably your identity isn't so tied up in 0:20:09.920 --> 0:20:13.720 you know, whether secondhand smoke is a health hazard versus uh, 0:20:13.960 --> 0:20:17.080 you know something about you know, abortion is wrong, or 0:20:17.119 --> 0:20:20.440 you know, whatever your political conviction was that we analyzed 0:20:20.440 --> 0:20:20.960 in advance. 0:20:35.920 --> 0:20:38.000 So this leads us to the question, I think, if 0:20:38.320 --> 0:20:40.960 what is belief for from an evolutionary point of view, 0:20:41.040 --> 0:20:45.919 what are these beliefs useful for doing for for the 0:20:45.960 --> 0:20:49.760 rest of the brain. One idea about beliefs is that 0:20:50.840 --> 0:20:54.040 they're trying to build a an accurate model of the world. 0:20:54.560 --> 0:20:56.600 Another version of beliefs is that it has to do 0:20:56.720 --> 0:21:01.879 with something social, as in belonging, with identity and the 0:21:02.240 --> 0:21:05.639 capitlain and all. Study you just pointed two would certainly 0:21:05.640 --> 0:21:08.679 support that. And then another that people propose that has 0:21:08.720 --> 0:21:13.000 to do with emotional regulation. It makes you feel better, more certain, 0:21:13.080 --> 0:21:15.640 less anxious about particular things, especially I think that would 0:21:15.680 --> 0:21:17.960 apply to letus say, religious beliefs. And it may not 0:21:18.000 --> 0:21:20.920 be that there's anything exclusive about these answers, but if 0:21:20.920 --> 0:21:24.600 we were thinking about waiting them, how do you see 0:21:24.640 --> 0:21:25.719 the function of beliefs? 0:21:25.720 --> 0:21:31.760 Well, I think it's subsumes almost every act of cognition 0:21:32.920 --> 0:21:37.639 apart from kind of pure kind of sensory engagement with 0:21:37.720 --> 0:21:43.159 the world. And even in that case, you can you 0:21:43.200 --> 0:21:47.680 can translate the sensory experience into kind of belief talk. 0:21:48.000 --> 0:21:49.840 I mean, it doesn't have the we don't it's not 0:21:49.920 --> 0:21:52.800 mediated linguistically in the same way. But like my belief 0:21:53.520 --> 0:21:56.199 that that's a table, it's built up over you know, 0:21:56.440 --> 0:21:58.919 you can in many channels. One channel as I can 0:21:58.960 --> 0:22:00.840 see it, and I can see that, you know, supporting 0:22:00.880 --> 0:22:03.560 your drink, and so we're using that as a table 0:22:04.040 --> 0:22:09.879 whatever it is. But the linguistic mediation comes into play 0:22:09.920 --> 0:22:14.199 when we might say, oh, would you just would you 0:22:14.200 --> 0:22:16.239 go put that over on the table. It's like then, 0:22:16.640 --> 0:22:18.600 so now I have this abstract representation of the table, 0:22:18.640 --> 0:22:21.040 I walk into the room, I find the table, right. 0:22:21.080 --> 0:22:25.760 So obviously we're engaging this in multiple modes. But once 0:22:25.800 --> 0:22:29.480 you break free of just moment to moment, you know, 0:22:30.240 --> 0:22:34.480 behavioral imperatives of navigating that, you know, our mediate environment, 0:22:36.119 --> 0:22:42.199 it's almost all linguistic or you know, imagistic representations of 0:22:42.359 --> 0:22:46.040 possible states of the future, you know, plausible states of 0:22:46.080 --> 0:22:50.119 the past. You know, do we try to reconcile our memory, 0:22:50.119 --> 0:22:52.960 you know, our memories when there's any kind of discordance there. 0:22:53.000 --> 0:22:55.480 But again, we're just trading in language. Oh no, no, 0:22:55.520 --> 0:22:57.359 he didn't say that. He said this, Or no, no, 0:22:57.440 --> 0:22:59.640 that wasn't. That wasn't on Tuesday. That was on Wednesday, 0:22:59.680 --> 0:23:02.480 And I mean it was It's all we're doing is 0:23:02.520 --> 0:23:06.000 talking to ourselves and talking to others about what the 0:23:06.040 --> 0:23:08.439 world is like and what our place in it is 0:23:08.520 --> 0:23:11.159 and what should we do next. I mean, we have 0:23:11.240 --> 0:23:18.000 just we have this massive navigation problem which covers really 0:23:18.080 --> 0:23:20.960 our life in every respect. I mean even you know, 0:23:21.040 --> 0:23:24.400 I view morality as a navigation problem, and morality really 0:23:24.440 --> 0:23:28.320 is a story of what should we do next, you know, 0:23:28.480 --> 0:23:30.280 or in the future, right, Like, what is what's the 0:23:30.359 --> 0:23:32.200 right thing to do? So you get two people in 0:23:32.240 --> 0:23:35.560 a room and they're for whatever reason, their incentives aren't aligned, 0:23:35.560 --> 0:23:38.040 and there's some kind of negotiation, and then it immediately 0:23:38.080 --> 0:23:40.119 becomes a conversation about what's the right thing to do, 0:23:40.160 --> 0:23:42.000 what's the fair thing to do, what's the what do 0:23:42.119 --> 0:23:45.520 we do last time? And if you actually kind of 0:23:45.600 --> 0:23:48.600 drill down on what's happening at each point along the way, 0:23:48.640 --> 0:23:53.359 and what is anchoring everyone's emotional response. You're looking at 0:23:53.760 --> 0:23:56.240 knowledge claims about the way the world is, the way 0:23:56.240 --> 0:24:00.000 that it's likely to be, and people's kind of the waitings, 0:24:00.000 --> 0:24:03.359 the emotional waitings. People are giving these claims with respect 0:24:03.400 --> 0:24:06.159 to kind of a probabilistic sense of the likelihood that 0:24:06.160 --> 0:24:10.239 they're true or false. Right, So, if someone says to you, oh, no, no, no, 0:24:10.280 --> 0:24:15.960 that's not what happened. There's a very controversial shooting in 0:24:16.000 --> 0:24:18.040 the news right now that has kind of shattered the 0:24:18.040 --> 0:24:21.720