WEBVTT - Ep122 "Why do we so rarely say what we mean?" (with Steven Pinker) 0:00:05.120 --> 0:00:08.760 Why do people speak in innuendo when they're on a date. 0:00:09.440 --> 0:00:14.000 Why do dictators try to squelch protests, Why do we 0:00:14.520 --> 0:00:17.520 join up with bullies to gang up on an outcast. 0:00:18.079 --> 0:00:20.799 Why do humans stand out from the rest of the 0:00:20.840 --> 0:00:25.720 animal kingdom by blushing and laughing and crying? And what 0:00:25.760 --> 0:00:28.720 does any of this have to do with George Costanza 0:00:29.200 --> 0:00:33.840 or when Harry met Sally, or anonymity on social media 0:00:34.000 --> 0:00:39.080 or cancel culture, or why we generally don't say everything 0:00:39.280 --> 0:00:45.920 we mean. Welcome to Intercosmos with me David Eagleman. I'm 0:00:45.920 --> 0:00:49.480 a neuroscientist and author at Stanford and in these episodes 0:00:49.520 --> 0:00:53.160 we sail deeply into our three pound universe to understand 0:00:53.240 --> 0:00:55.959 why and how our lives looks the way they do. 0:01:13.080 --> 0:01:17.479 Today's episode is about a phenomenon known as common knowledge, 0:01:17.880 --> 0:01:21.039 which is something that I know and you know, and 0:01:21.120 --> 0:01:24.280 we both know that we know it. Now, this could 0:01:24.319 --> 0:01:26.920 seem like a very particular sort of thing to pay 0:01:26.959 --> 0:01:31.039 attention to, but many psychologists and economists over the past 0:01:31.120 --> 0:01:34.600 decades have started to think that a deeper understanding of 0:01:35.200 --> 0:01:39.319 common knowledge could explain all kinds of things about human 0:01:39.400 --> 0:01:43.280 nature and behavior and societies, and for a very long time. 0:01:43.319 --> 0:01:46.280 This has grabbed the attention of my friend and colleague 0:01:46.319 --> 0:01:49.040 Stephen Pinker, who just this week has a new book 0:01:49.080 --> 0:01:53.800 coming out on common knowledge called When Everyone Knows That 0:01:53.960 --> 0:01:56.920 Everyone Knows, And so I called him up to discuss 0:01:57.000 --> 0:01:59.520 this topic. I'll take just a moment to frame this 0:01:59.680 --> 0:02:02.320 before I begin the interview. At the heart of the 0:02:02.440 --> 0:02:07.280 issue is that we are a massively social species. We 0:02:07.400 --> 0:02:11.400 form lifelong relationships, and we join clubs, and we're parts 0:02:11.440 --> 0:02:14.919 of tribes, and we're citizens of countries. And we're also 0:02:15.080 --> 0:02:18.080 a highly intelligent species, and we spend a lot of 0:02:18.080 --> 0:02:23.320 our time, usually unconsciously, figuring out who knows what and 0:02:23.480 --> 0:02:26.840 what we know in common, and for that matter, thinking 0:02:26.840 --> 0:02:30.840 about how we can expand common knowledge with the right signals, 0:02:31.080 --> 0:02:36.080 and often how we could hide things from becoming common knowledge. 0:02:36.639 --> 0:02:39.079 The key thing to understand for today's conversation is that 0:02:39.440 --> 0:02:42.960 common knowledge is not just about a bunch of individuals 0:02:42.960 --> 0:02:45.680 each knowing something. It's that each person knows it and 0:02:45.800 --> 0:02:48.760 knows that everyone else knows it, and knows that everyone 0:02:48.760 --> 0:02:51.200 else knows that they know it, and so on. And 0:02:51.240 --> 0:02:55.160 the argument is that it's this ladder of shared awareness 0:02:55.680 --> 0:03:00.920 that allows societies to coordinate. Think about something like the 0:03:00.919 --> 0:03:04.560 game of chicken, where two drivers speed towards each other. 0:03:04.960 --> 0:03:08.240 Each knows the situation, but the critical factor is whether 0:03:08.639 --> 0:03:11.640 both drivers know what the other is willing to do, 0:03:11.720 --> 0:03:14.720 and whether both know that the other knows. And the 0:03:14.760 --> 0:03:18.040 effects of common knowledge stretch from two people all the 0:03:18.080 --> 0:03:21.920 way up to countries. For example, history is filled with 0:03:22.040 --> 0:03:27.079 moments when private thoughts turned into common knowledge and changed 0:03:27.120 --> 0:03:30.160 the world. So, for example, in nineteen eighty nine, East 0:03:30.200 --> 0:03:33.400 Germans had long doubted the regime, but it was only 0:03:33.680 --> 0:03:37.360 when tens of thousands gathered in the streets when everyone 0:03:37.400 --> 0:03:41.240 could see that everyone else had the same doubts. That's 0:03:41.320 --> 0:03:45.120 when the Berlin Wall fell. Stock Market bubbles and crashes 0:03:45.280 --> 0:03:48.480 run on the same sort of principle. Investors don't care 0:03:48.840 --> 0:03:51.960 only about the value of a stock, but about what 0:03:52.080 --> 0:03:56.800 everyone else believes everyone else believes about its value. So 0:03:56.960 --> 0:03:59.720 this is the type of thing that Pinker's book explores, 0:03:59.800 --> 0:04:04.160 all all the ways in which common knowledge permeates everyday life. 0:04:06.040 --> 0:04:10.000 Common knowledge, for example, is why etiquette works. You don't 0:04:10.040 --> 0:04:12.640 just know the rules, you know that others know them too. 0:04:13.040 --> 0:04:17.200 It's why red lights function not because you fear the police, 0:04:17.240 --> 0:04:19.840 but because you know that everyone else knows the rule 0:04:20.120 --> 0:04:22.760 and is going to stop. It's why children learn to 0:04:22.760 --> 0:04:25.800 play Peek a boo, because the delight comes from that 0:04:26.000 --> 0:04:29.080 shared loop of I know that, you know that I'm here. 0:04:29.640 --> 0:04:33.400 So today we'll explore the phenomenon of common knowledge. Stephen 0:04:33.400 --> 0:04:36.800 Pinker is a cognitive scientist and linguist at Harvard and 0:04:36.839 --> 0:04:41.040 he's a longtime bestselling author who is famous for illuminating 0:04:41.080 --> 0:04:44.560 the hidden structures of human thought and society. His new 0:04:44.600 --> 0:04:48.560 book dives into the puzzle of common knowledge, how it arises, 0:04:48.640 --> 0:04:52.240 why it matters, and what it reveals about the architecture 0:04:52.560 --> 0:05:00.719 of our social minds. Stephen joins me, Now, so, Steve, 0:05:00.800 --> 0:05:04.520 we are an intensely social species and there's a lot 0:05:04.600 --> 0:05:07.000 that has to happen in order to get us to 0:05:07.040 --> 0:05:09.120 coordinate as a result. And this is the thing you've 0:05:09.160 --> 0:05:13.200 been thinking about, So tell us how do we coordinate 0:05:13.240 --> 0:05:13.960 as a species. 0:05:14.640 --> 0:05:20.200 Well, any two agents who need to coordinate need common knowledge. 0:05:20.320 --> 0:05:23.520 The theme of the book, common knowledge, being the state 0:05:23.520 --> 0:05:26.200 where I know something, you know it, I know that 0:05:26.240 --> 0:05:27.880 you know it, you know that I know it, I 0:05:27.960 --> 0:05:29.920 know that you know that I know that you know it, 0:05:30.000 --> 0:05:34.200 ad infinitum. Why Because it isn't enough for each party 0:05:34.240 --> 0:05:35.680 to know what the other one is going to do, 0:05:36.160 --> 0:05:38.680 because the other party guessing what the first one is 0:05:38.720 --> 0:05:40.880 going to do may do something complete different. So just 0:05:41.040 --> 0:05:46.280 be concrete. If we're going to rendezvous and we don't 0:05:46.320 --> 0:05:49.200 generate common knowledge by a conversationalist, and my cell phone 0:05:49.240 --> 0:05:51.320 goes dead, so each of us asked to guess where 0:05:51.360 --> 0:05:53.560 the other one is going to go. It's not enough 0:05:53.600 --> 0:05:55.520 for me to know that you like to go to Starbucks, 0:05:55.880 --> 0:05:58.200 because you may know that I like to go to Pete's. 0:05:58.320 --> 0:06:00.320 And so if I go to Starbucks, that's where you're 0:06:00.320 --> 0:06:01.920 going to go. You might go to pizza because you 0:06:01.920 --> 0:06:04.200 think that's where I'm going to go. And well, I 0:06:04.240 --> 0:06:06.480 know that, okay, so I'll go to Pietz because Dave 0:06:06.520 --> 0:06:07.680 knows that I like to go to pizza. But wait 0:06:07.720 --> 0:06:09.520 a sec Dave knows that I know they likes to 0:06:09.520 --> 0:06:11.400 go to Starbucks, so he's going to go to Starbucks 0:06:11.440 --> 0:06:15.640 after all, and so on. Nothing short of actually blurting 0:06:15.640 --> 0:06:18.800 it out in each other's presence will get you on 0:06:18.880 --> 0:06:24.320 the same page. Some kind of public perceptible self evidence signal. 0:06:24.440 --> 0:06:27.200 That's what is needed for coordination. 0:06:27.800 --> 0:06:30.479 You've, of course spent much of your career studying language, 0:06:30.920 --> 0:06:36.200 and so you see language as one way of establishing 0:06:36.240 --> 0:06:39.159 that common knowledge give us a sense of that, Yeah, 0:06:39.240 --> 0:06:39.840 you know that. 0:06:39.839 --> 0:06:42.920 I'm trying to get you to believe something because you 0:06:43.000 --> 0:06:45.800 know that I'm saying something with the intent that you 0:06:45.839 --> 0:06:48.080 believe it. That's kind of what language is. So it's 0:06:48.120 --> 0:06:53.120 a common knowledge generator when it is something is blurted out. 0:06:53.880 --> 0:06:56.479 What got me interested in this whole topic is actually 0:06:56.480 --> 0:07:00.280 almost the converse cases in which we try to avoid 0:07:00.600 --> 0:07:04.480 common knowledge when we don't say something in so many words, 0:07:05.240 --> 0:07:08.680 but we put our meaning between the lines. We count 0:07:08.680 --> 0:07:11.040 on our reader to connect the dots. We use euphemism 0:07:11.160 --> 0:07:14.320 or innuendo or hinting or beating around the bush or 0:07:14.360 --> 0:07:17.080 hilly shallowing, which is a lot of language. That's one 0:07:17.080 --> 0:07:19.480 of the reasons it took so long to get computers 0:07:19.480 --> 0:07:22.600 to understand language. If you simply parse who did what 0:07:22.680 --> 0:07:24.600 to whom based on the subject of the verb and 0:07:24.640 --> 0:07:27.200 the object, you're really not going to understand what people 0:07:27.360 --> 0:07:30.720 actually meant, such as if you could pass a salt, 0:07:30.720 --> 0:07:34.600 that would be awesome. Okay, now think about that. I mean, 0:07:34.640 --> 0:07:37.160 that doesn't make it much sense. It would literally be awesome, 0:07:37.480 --> 0:07:41.640 And you know, it's not like you're just pondering possible worlds. 0:07:41.680 --> 0:07:43.760 That's not the meaning. Everyone knows what the meaning is. 0:07:43.800 --> 0:07:46.760 It's give me the salt, and a lot of languages 0:07:46.840 --> 0:07:48.800 like that, and linguists have long known it. But the 0:07:48.880 --> 0:07:52.120 question is why what do we try to accomplish when 0:07:52.200 --> 0:07:55.800 we avoid blurting something what we want out? In so 0:07:55.840 --> 0:07:58.800 many words, what I suggest is that the we're avoiding 0:07:58.840 --> 0:08:02.080 common knowledge. That is, each one knows what the other 0:08:02.120 --> 0:08:04.280 one is doing, but you may not know that the 0:08:04.320 --> 0:08:06.240 other one knows that you know that they know, and 0:08:06.280 --> 0:08:10.360 that allows you to preserve a certain relationship, relationships being 0:08:10.800 --> 0:08:14.800 coordination problems, as we mentioned at the top of the conversation, 0:08:15.240 --> 0:08:19.840 a relationship like being friends, being lovers, being a supervisor 0:08:19.840 --> 0:08:23.560 in supervisory, being transaction partners. Those are all matters of 0:08:23.600 --> 0:08:26.920 common knowledge. We're friends not because we signed a contract, 0:08:26.960 --> 0:08:28.880 but because each one knows that the other one knows 0:08:28.920 --> 0:08:32.240 that there we're friends, and that can be threatened by 0:08:32.600 --> 0:08:36.120 certain things that could become a common knowledge that contradict 0:08:36.160 --> 0:08:40.400 the basis of the friendship, like a sexual proposition. So 0:08:40.559 --> 0:08:43.040 why do people say things like I want to come 0:08:43.120 --> 0:08:45.560 up for Netflix and show, or you want to come 0:08:45.600 --> 0:08:48.760 up for coffee when you know, though you know, let's 0:08:48.760 --> 0:08:50.440 say it's a man saying it to a woman. You know, 0:08:50.600 --> 0:08:52.800 she wasn't born yesterday. She's a grown up, she knows 0:08:52.840 --> 0:08:56.360 what it means. But it's still way better than Hey, 0:08:56.400 --> 0:08:58.680 you want to come up and have sex, which would 0:08:59.040 --> 0:09:02.960 be you know, both parties. You are pretty uncomfortable, even 0:09:02.960 --> 0:09:05.280 though would you like to come up for coffee? Doesn't 0:09:05.280 --> 0:09:07.480 make them uncomfortable? How come that was the problem that 0:09:07.520 --> 0:09:09.880 I took up in a previous book, The Stuff of Thought. 0:09:10.120 --> 0:09:12.679 Language is a Window into human nature, which had a 0:09:12.800 --> 0:09:16.000 chapter called games People play on language as a window 0:09:16.040 --> 0:09:19.920 into social relationships and in trying to figure out why 0:09:19.960 --> 0:09:24.119 we don't just blurt out what we mean. Other examples 0:09:24.160 --> 0:09:27.240 being say a failed bribe. Let's see you trying to 0:09:27.440 --> 0:09:30.040 jump the queue in a restaurant and you slip the 0:09:30.160 --> 0:09:32.960 major DA twenty dollars bill and say, I just wondering 0:09:32.960 --> 0:09:36.560 if you might have a cancelation, or this is an 0:09:36.559 --> 0:09:38.400 important night from you. Is there any way to shorten 0:09:38.440 --> 0:09:41.719 my weight? Why don't people just say if I give 0:09:41.760 --> 0:09:45.559 you twenty dollars, will you see me? Right? Away or fundraising. 0:09:45.600 --> 0:09:48.079 I've seen this a lot at Harvard. I'm sure you've 0:09:48.080 --> 0:09:50.720 seen a similar thing where the dean will say to 0:09:50.760 --> 0:09:53.520 the rich people in the audience, we're counting on you 0:09:53.600 --> 0:09:57.600 to show leadership, to be a friend to the university 0:09:58.000 --> 0:10:00.520 instead of the reason we're all here is you're going 0:10:00.520 --> 0:10:03.120 to open your checkbook and write, you know, a check 0:10:03.160 --> 0:10:06.680 for five million dollars. That's another case where people don't 0:10:06.720 --> 0:10:10.120 say what they mean. Why not? And here's the answer 0:10:10.160 --> 0:10:13.200 that got me interested in common knowledge. And I've done 0:10:13.200 --> 0:10:16.839 studies to back this up that if it's do you 0:10:16.920 --> 0:10:19.440 want to come up for coffee? Well, you know, she 0:10:19.559 --> 0:10:22.160 knows what he means, and you know obviously he knows 0:10:22.160 --> 0:10:25.400 what he means. But does she know that he knows 0:10:25.480 --> 0:10:29.560 that she knows? With an innuendo like would you like 0:10:29.600 --> 0:10:32.160 to come up for coffee, she could think, well, maybe 0:10:32.160 --> 0:10:34.720 he thinks I'm naive, and if I said no, maybe 0:10:34.720 --> 0:10:37.600 he thinks, you know, caffeine would keep me up. Even 0:10:37.600 --> 0:10:39.760 though she knows that she's turned down a sexual overture, 0:10:39.800 --> 0:10:41.840 he knows it as well, but he could not know 0:10:41.840 --> 0:10:43.800 why because she knows that he knows. And likewise he 0:10:43.840 --> 0:10:46.400 could think, well, you know, maybe she thinks I'm dead, 0:10:46.720 --> 0:10:49.679 Maybe she thinks that I think that she's just turned 0:10:49.679 --> 0:10:55.280 down coffee. Uh. They can maintain their platonic friendship with 0:10:55.400 --> 0:11:00.959 the common knowledge that it's just about companionship. Whereas he 0:11:01.040 --> 0:11:02.560 said you want to come up for half sex and 0:11:02.640 --> 0:11:06.320 she said no, they can never be platonic friends in 0:11:06.360 --> 0:11:09.400 the same way. Again, the intuition is it's out there, 0:11:09.600 --> 0:11:13.560 you can't take it back, And I suggest that technically 0:11:13.640 --> 0:11:17.800 what's happening is that the blurted out speech generates common knowledge. 0:11:18.040 --> 0:11:22.240 Common knowledge is the basis of our relationships. Their coordination, games, 0:11:22.840 --> 0:11:28.200 euphemism and innuendo get a message across without generating common knowledge, 0:11:28.200 --> 0:11:30.240 and that's why we fall back on it so often. 0:11:30.559 --> 0:11:34.559 Okay, so that's how we sometimes try to mask common knowledge. 0:11:35.480 --> 0:11:39.040 Tell us about how common knowledge is useful in society, 0:11:39.200 --> 0:11:43.959 society wide, let's say, with public demonstrations and politics and economics. 0:11:44.320 --> 0:11:47.640 Yeah, a lot of our large scale coordination, not just 0:11:48.000 --> 0:11:52.160 two friends or Roande going for coffee or agreeing to 0:11:52.200 --> 0:11:57.000 be platonic friends, but large scale things like everyone recognizing money, 0:11:57.559 --> 0:12:01.520 Like why do I accept a green piece of paper 0:12:01.520 --> 0:12:04.120 in exchange for something of value? Well, because I know 0:12:04.200 --> 0:12:07.040 that other people will accept it and give me something 0:12:07.040 --> 0:12:08.840 of value. Why would they do that, Well, they know 0:12:08.920 --> 0:12:11.800 that still other people would accept it. So the value 0:12:11.800 --> 0:12:17.120 of currency depends on common knowledge. Everyone knows it's worth something, 0:12:17.160 --> 0:12:18.880 and that's what makes it worth something. The fact that 0:12:18.920 --> 0:12:22.200 everyone knows that everyone knows it. A lot of power 0:12:22.440 --> 0:12:26.160 depends on common knowledge. There are laws, there's courts, there's 0:12:26.160 --> 0:12:28.200 a police force, there's a jail. But most of the 0:12:28.200 --> 0:12:31.240 time people just follow the law, even though big brothers 0:12:31.480 --> 0:12:36.559 watching them twenty four to seven. However, these things can change. 0:12:37.760 --> 0:12:40.520 It's not easy to change them when the basis of 0:12:40.720 --> 0:12:44.520 power or money is just common knowledge, because everyone has 0:12:44.559 --> 0:12:48.600 an interest in keeping up the common assumption. But sometimes 0:12:48.640 --> 0:12:52.360 it can unravel. In the case of power, if there 0:12:52.440 --> 0:12:56.600 is a public protest, everyone shows up at a public 0:12:56.640 --> 0:12:59.680 square at the same time, the same place, everyone sees 0:12:59.720 --> 0:13:04.720 everyone else there. Previously, maybe that everyone was resentful of 0:13:04.760 --> 0:13:08.559 the system, thought it was inefficient and oppressive. They may 0:13:08.600 --> 0:13:11.400 even have suspected that everyone else had the same feeling, 0:13:11.440 --> 0:13:13.640 but they didn't know that other people knew that. They 0:13:13.760 --> 0:13:17.760 knew they couldn't coordinate by all rising at the same time, 0:13:18.200 --> 0:13:20.920 and so the regime could keep them in their place 0:13:21.320 --> 0:13:25.160 by preventing common knowledge. And that's why dictators don't allow 0:13:25.240 --> 0:13:28.240 freedom of assembly, freedom of the press, freedom of speech, 0:13:28.640 --> 0:13:34.320 precisely because they're afraid that people coordinating which they could 0:13:34.320 --> 0:13:40.240 only do with common knowledge, could acting together overpower a regime. Likewise, 0:13:40.280 --> 0:13:43.360 in the case of going back to money again, if 0:13:43.400 --> 0:13:47.240 the value of money depends on common knowledge, then when 0:13:47.240 --> 0:13:50.559 the common knowledge is threatened, the value of money can disappear. 0:13:50.559 --> 0:13:52.960 And that's what happens when you get hyperinflation, people taking 0:13:52.960 --> 0:13:55.280 home their wages in a wheelbarrow because no one will 0:13:55.640 --> 0:14:00.480 accept it anymore, or a bank run where people withdraw 0:14:00.520 --> 0:14:03.640 their savings, not necessarily because they think that there's anything 0:14:03.640 --> 0:14:06.079 wrong with a bank, but as long as there's a 0:14:06.200 --> 0:14:08.560 rumor that other people think that there's a problem with 0:14:08.600 --> 0:14:11.080 the bank, and they're withdrawing their money out of fear 0:14:11.120 --> 0:14:13.480 that still other people will withdraw their money, it suddenly 0:14:13.480 --> 0:14:17.040 becomes rational to withdraw your money while the bank still 0:14:17.080 --> 0:14:19.400 has money to withdraw. And that can cause a bank 0:14:19.440 --> 0:14:21.640 to fail, that can cause the whole economy to fail. 0:14:21.640 --> 0:14:24.400 That's what happened in nineteen twenty nine. And so when 0:14:24.520 --> 0:14:27.360 Roosevelt said the only thing we have to fear is 0:14:27.400 --> 0:14:31.880 fear itself. He was stating a theorem of common knowledge 0:14:31.920 --> 0:14:34.560 that was quite literally true, that what people had to 0:14:34.600 --> 0:14:37.000 fear was fear itself, and the fear of fear, the 0:14:37.040 --> 0:14:41.240 recursive fear, the common knowledge, could actually change the value 0:14:41.280 --> 0:14:44.000 of those financial institutions. 0:14:45.440 --> 0:14:47.480 So here's something I wanted to dig in with you 0:14:47.560 --> 0:14:50.080 about after reading your book. How do we think about 0:14:50.480 --> 0:14:54.040 false common knowledge? By which I mean, let's imagine that 0:14:54.080 --> 0:14:56.320 you and I engage in a public protest and we 0:14:56.320 --> 0:14:58.200 look around and we see a thousand people around us. 0:14:58.200 --> 0:15:01.240 We say, look, everybody clear feels this way, but we're 0:15:01.240 --> 0:15:04.280 not aware of that across town there's a larger protest 0:15:04.320 --> 0:15:07.160 with ten thousand people in it, and we have the 0:15:07.160 --> 0:15:10.520 impression that everyone feels the same way we do about something. 0:15:10.840 --> 0:15:14.000 I mean that technically be common belief rather than common knowledge, 0:15:14.040 --> 0:15:17.720 But different pools of people can have different common beliefs, 0:15:18.080 --> 0:15:22.200 and there can also be common misconceptions where prior to 0:15:22.280 --> 0:15:27.400 the protest, there are cases where people think that everyone 0:15:27.400 --> 0:15:30.280 else believes something. In fact, everyone could believe that everyone 0:15:30.280 --> 0:15:33.240 else believes someone something and no one actually believes it, 0:15:33.360 --> 0:15:37.360 sometimes called a pluralistic ignorance. Or a spiral of silence. 0:15:37.560 --> 0:15:38.680 What's an example of that. 0:15:39.280 --> 0:15:43.359 A classic case study of pluralistic ignorance in social psychology 0:15:43.640 --> 0:15:47.840 was when some psychologists interviewed the guys in the fraternity. 0:15:48.400 --> 0:15:50.160 They found that every one of them thought that it 0:15:50.200 --> 0:15:52.800 was really stupid to drink so much that you pass out, 0:15:53.240 --> 0:15:57.080 but everyone thought that all the other frat bros thought 0:15:57.120 --> 0:15:59.480 it was cool. No one actually thought it was cool, 0:15:59.480 --> 0:16:03.000 but that all the others thought it was cool. And 0:16:03.160 --> 0:16:05.440 there are probably a lot of cases like that. I mean, 0:16:05.720 --> 0:16:08.640 an extreme case would be The Emperor's New Clothes, where 0:16:08.720 --> 0:16:12.280 everyone thought that everyone else thought that who were seeing clothes, 0:16:12.360 --> 0:16:14.720 no one actually saw clothes, And it took the little 0:16:14.720 --> 0:16:19.640 boy blurting it out generating common knowledge, for the common 0:16:19.640 --> 0:16:25.640 misconception to flip into common knowledge. The Emperor's New Clothes 0:16:25.720 --> 0:16:28.800 is a story about common knowledge. The boy wasn't telling 0:16:29.000 --> 0:16:32.600 anyone anything they didn't already know, but it was changing 0:16:32.640 --> 0:16:35.800 the state of their knowledge because now everyone knew that 0:16:35.840 --> 0:16:39.280 everyone else knew, and that changed their relationship with the 0:16:39.360 --> 0:16:43.680 Emperor from a deference to scorn and ridicule. 0:16:59.600 --> 0:17:02.440 I do worry a little bit, though, about people assuming 0:17:02.640 --> 0:17:07.640 politically common knowledge and saying, Hey, if I just make 0:17:07.680 --> 0:17:11.040 some innuendo, everyone will understand what I mean by this, 0:17:11.280 --> 0:17:14.320 because that often doesn't work, especially now. 0:17:14.760 --> 0:17:16.760 Well, the thing about innuendo is that it has to 0:17:16.800 --> 0:17:24.520 be calibrated so that it is recognized by a kind 0:17:24.520 --> 0:17:29.119 of willing recipient, but can be denied by an unwilling recipient. 0:17:29.160 --> 0:17:32.439 So it has to be calibrated in that zone, and 0:17:32.480 --> 0:17:35.719 there can be errors in either direction. Where there's an 0:17:35.760 --> 0:17:40.919 episode of Seinfeld where George Costanza is invited up for 0:17:40.960 --> 0:17:43.359 coffee and says no because he's got to get to 0:17:43.359 --> 0:17:45.960 work early the next morning, and then as he's walking out, 0:17:46.280 --> 0:17:48.600 he says, oh, my god, coffee doesn't mean coffee. Coffee 0:17:48.680 --> 0:17:52.800 in sex. So there's the Costanza problem that it could 0:17:52.920 --> 0:17:56.399 be so subtle that it goes over the head, or 0:17:56.440 --> 0:18:00.080 there could be conversely, it's so blatant that the the 0:18:00.600 --> 0:18:04.560 unwilling hearer calls you on it again. You know, all 0:18:04.560 --> 0:18:07.560 of these things, by the way, are worked out in fiction, 0:18:07.840 --> 0:18:12.720 in comedies, comedies of manners, situation comedies. They kind of 0:18:12.880 --> 0:18:19.199 allow us to exercise our facility for recursive mentalizing, that is, 0:18:19.280 --> 0:18:21.680 getting inside the head of other people, getting inside the 0:18:21.840 --> 0:18:24.040 head of other people and so they're often worked out 0:18:24.280 --> 0:18:28.360 that so often were drives fictional plots. But the opposite 0:18:28.400 --> 0:18:32.800 is when when Harry met Sally, and Harry, you know, 0:18:32.880 --> 0:18:36.399 early on, is kind of complimenting Sally and they just 0:18:36.480 --> 0:18:39.480 met kind of a little too insistently, and then she 0:18:39.640 --> 0:18:42.520 blows the listle. She says, you're coming on to me, 0:18:42.920 --> 0:18:46.640 which leads to a wonderful discussion of common knowledge. I mean, 0:18:46.680 --> 0:18:50.200 not not in those words where he says, okay, let's 0:18:50.240 --> 0:18:51.680 say I was coming on to you. What are we 0:18:51.720 --> 0:18:53.760 going to do? I take it back? Okay, I take 0:18:53.760 --> 0:18:56.600 it back, and she says, you can't take it back. 0:18:57.080 --> 0:18:58.600 He says, what do you mean you can't take it back? 0:18:58.640 --> 0:18:59.680 You know, what are we going to do? Call the 0:18:59.720 --> 0:19:03.480 cop and she says, it's out there. It's too late, 0:19:04.200 --> 0:19:08.600 So it's out there. That is a metaphor for common knowledge. 0:19:08.840 --> 0:19:11.600 That is something that's out there, is something that you 0:19:11.680 --> 0:19:15.360 see other people see, you see them see it. And 0:19:15.840 --> 0:19:18.679 direct speech or even in this case, indirect speech that 0:19:18.880 --> 0:19:22.359 was not indirect enough. It kind of exceeded that. The 0:19:22.400 --> 0:19:26.159 cutoff is out there, and when it's out there, it 0:19:26.280 --> 0:19:29.359 changes the nature of the relationship. They were no longer 0:19:29.520 --> 0:19:33.680 just near strangers, platonic friends. He had turned it into 0:19:34.000 --> 0:19:36.560 a sexual relationship, which you rebuffed. 0:19:37.080 --> 0:19:39.359 Great, So I want to return for just a second 0:19:39.440 --> 0:19:43.440 to literature, which you mentioned fictions, because I made the 0:19:43.520 --> 0:19:46.399 argument on this podcast little while ago that I'm not 0:19:46.760 --> 0:19:50.800 so worried about AI completely taking the job of writers. 0:19:51.600 --> 0:19:53.600 And I listened five different reasons, but one of them 0:19:53.640 --> 0:19:57.760 had to do with the fact that we could all 0:19:57.880 --> 0:20:01.600 generate totally bespoke literature, just like Kings of Yesteryear would do. 0:20:03.040 --> 0:20:04.960 But we lose something there, which is that a big 0:20:05.000 --> 0:20:07.760 part of literature is the social glue, the fact that 0:20:07.800 --> 0:20:10.040 everyone else has read the same story. I don't want 0:20:10.080 --> 0:20:13.119 my Game of Thrones to have a different outcome than 0:20:13.160 --> 0:20:16.840 your Game of Thrones. So my question to you is, 0:20:17.160 --> 0:20:19.960 what is the reason we desire common knowledge so much? 0:20:20.560 --> 0:20:22.760 I think it's a great example, and people may not 0:20:22.840 --> 0:20:27.520 remember that back in the nineties, when the internet first 0:20:27.560 --> 0:20:30.520 became a thing, there was the idea that you could 0:20:31.480 --> 0:20:33.840 dial in whatever ending to a story you wanted. That 0:20:33.960 --> 0:20:36.880 fiction would be, movies would be the same. Everyone could 0:20:36.880 --> 0:20:39.439 watch that movie. Maybe let's they didn't take off. And 0:20:39.520 --> 0:20:43.360 I think it's the reason that you identified, namely part 0:20:43.359 --> 0:20:47.880 of the experience of art is that it's common knowledge. 0:20:48.400 --> 0:20:51.080 You know about something at the same time you know 0:20:51.119 --> 0:20:54.399 that everyone else knows about it, and that's what gives 0:20:54.400 --> 0:20:59.280 you something in common that can reinforce a social relationship. 0:20:59.320 --> 0:21:01.679 With friendship, a movie with friends, you talk about it 0:21:01.720 --> 0:21:05.200 with friends, and the common experience is one of those 0:21:05.240 --> 0:21:10.199 things that kind of go makes friends friends. They go 0:21:10.280 --> 0:21:14.560 through things together, they share common interests. The basis, the 0:21:14.920 --> 0:21:19.080 common knowledge, that's the tacit basis of friendship is that 0:21:19.119 --> 0:21:21.240 we're kind of there's a kind of a mind mild, 0:21:22.200 --> 0:21:25.760 even a you know, a body meld, where that we 0:21:25.800 --> 0:21:29.240 are in physical proximity, We hug, we shake hands, all 0:21:29.280 --> 0:21:31.440 the more intense and romantic relationship. 0:21:31.720 --> 0:21:33.720 Okay, So I want to return and dig in just 0:21:33.760 --> 0:21:36.359 a little on this point because I'm fascinated by this 0:21:36.560 --> 0:21:40.639 about false common knowledge what I'm calling that or a 0:21:40.680 --> 0:21:46.760 misconception about it. So, for example, recently, Charlie Kirk was 0:21:46.800 --> 0:21:50.399 assassinated in broad daylight, and if you look on X 0:21:50.440 --> 0:21:53.320 and if you look on blue Sky, you find very 0:21:53.359 --> 0:21:58.200 different stories about that. And presumably the people who are 0:21:58.240 --> 0:22:02.400 tweeting or blue skying are thinking, hey, this is great. 0:22:02.440 --> 0:22:04.760 We have shared common knowledge. But you in fact have 0:22:04.800 --> 0:22:08.520 two groups of people. I'm exaggerating a little bit the difference, 0:22:08.560 --> 0:22:12.560 but you have different groups that have beliefs that they 0:22:12.600 --> 0:22:17.359 believe are shared by everybody. Just one second example. This 0:22:17.560 --> 0:22:21.879 My grandmother I remember many years ago in Florida said 0:22:22.520 --> 0:22:25.080 I can't believe that so and so just one governor, 0:22:25.520 --> 0:22:28.679 because I don't know anybody that voted for him. And 0:22:28.720 --> 0:22:31.000 it was true, of course she didn't know anybody, but 0:22:31.040 --> 0:22:32.960 it doesn't mean that the majority of the state didn't 0:22:33.000 --> 0:22:33.479 vote for him. 0:22:33.480 --> 0:22:37.040 Nonetheless, Yeah, I mean common knowledge, or more accurately, in 0:22:37.080 --> 0:22:39.359 a lot of these cases, is common belief, That is, 0:22:39.359 --> 0:22:41.679 you believe something, you believe that other people believe that 0:22:41.680 --> 0:22:45.560 you believe it, and so on. Is relative to a network, 0:22:45.760 --> 0:22:48.720 a community which can be disconnected from another network, and 0:22:48.760 --> 0:22:51.280 the common knowledge is often generated since none of us 0:22:51.400 --> 0:22:56.320 experience everything firsthand. In fact, on for politics, we experience 0:22:56.359 --> 0:22:58.760 almost nothing firsthand, and we read about it, we hear 0:22:58.800 --> 0:23:03.560 about it. If the sources are disjoint, then the pools 0:23:03.560 --> 0:23:06.600 of common knowledge within each of these networks could be disjoined. 0:23:06.960 --> 0:23:11.520 And that happens partly from social media, as even feeds 0:23:11.560 --> 0:23:14.359 within a platform, but even more so when they're different 0:23:14.359 --> 0:23:17.880 platforms like X versus Blue Sky, or in the case 0:23:17.920 --> 0:23:22.040 of cable news, do you watch Fox News or do 0:23:22.040 --> 0:23:24.960 you watch CNN or do you watch MSNBC. So one 0:23:24.960 --> 0:23:26.800 of the users I take up in the book, and 0:23:26.840 --> 0:23:30.800 this intersects with my interest in academic freedom and freedom 0:23:30.840 --> 0:23:33.880