WEBVTT - Ep92 "Why is it so hard to keep a secret?" 0:00:05.080 --> 0:00:08.320 Why is it so hard to keep a secret? 0:00:08.560 --> 0:00:10.799 And what does this have to do with Abraham Lincoln's 0:00:10.800 --> 0:00:16.120 political cabinet or when bosses should keep secrets within companies? 0:00:16.680 --> 0:00:19.240 What does any of this have to do with political 0:00:19.440 --> 0:00:25.200 hierarchies or chimpanzees or the formula for Coca cola, or 0:00:25.680 --> 0:00:30.160 whether AI in the near future will be keeping secrets 0:00:30.240 --> 0:00:34.560 from you. Today's episode is all about secrets. We've all 0:00:34.840 --> 0:00:37.879 got them, from the little white lies we tell to 0:00:37.920 --> 0:00:41.640 spare somebody's feelings to the deep unspoken things that we 0:00:41.680 --> 0:00:45.879 try to bury. Secrets are a part of being a primate. 0:00:45.960 --> 0:00:48.680 But why do we have them, why do we keep them? 0:00:49.080 --> 0:00:52.440 And what happens when they start to unravel. As we'll see, 0:00:52.960 --> 0:00:57.880 neuroscience tells us that secrets aren't just stashed away. They're active. 0:00:58.000 --> 0:01:02.040 They weigh on us, They shape our relationships, and sometimes 0:01:02.560 --> 0:01:09.600 they grow into tangled webs we never meant to weave. Today, 0:01:09.600 --> 0:01:12.880 we'll dive into the neuroscience of secrets, how they form, 0:01:12.959 --> 0:01:15.560 how they grow, and what it takes to keep them 0:01:15.720 --> 0:01:18.720 or spill them. This is in her Cosmos, and I'm 0:01:18.800 --> 0:01:22.679 David Eagleman. Let's dive into our three pound universe to 0:01:22.959 --> 0:01:36.520 untangle the web. Now, before diving into the science of secrets, 0:01:36.560 --> 0:01:40.120 we'll start with an observation that researchers made sometime ago. 0:01:40.880 --> 0:01:45.560 Keeping a secret is unhealthy. So there's a psychologist named 0:01:45.600 --> 0:01:49.040 James Pennebaker, and he and his colleagues studied what happened 0:01:49.480 --> 0:01:53.680 when victims of rape or incest when they acted out 0:01:53.720 --> 0:01:59.200 of shame or guilt and chose to keep secrets inside. So, 0:01:59.240 --> 0:02:04.000 after years of study, Pennebaker concluded that quote, the act 0:02:04.240 --> 0:02:08.840 of not discussing or confiding the event with another maybe 0:02:09.000 --> 0:02:13.560 more damaging than having experienced the event per se. He 0:02:13.600 --> 0:02:17.880 and his team discovered that when subjects confesst or wrote 0:02:17.960 --> 0:02:23.120 about their deeply held secrets, their health improved. Their number 0:02:23.160 --> 0:02:27.359 of doctor visits went down, and there were measurable decreases 0:02:27.520 --> 0:02:31.080 in their stress hormone levels. So the results are clear enough. 0:02:31.440 --> 0:02:34.720 But some years ago I began to ask myself how 0:02:34.760 --> 0:02:38.320 to understand these findings from the point of view of 0:02:38.440 --> 0:02:41.040 brain science, and that led to a question that I 0:02:41.120 --> 0:02:47.919 realized was unaddressed in the scientific literature. What is a secret? Neurobiologically, 0:02:48.280 --> 0:02:53.760 imagine constructing an artificial neural network of millions of interconnected neurons. 0:02:54.320 --> 0:02:56.040 What would a secret look like? 0:02:56.400 --> 0:03:01.720 Here could a toaster with its interconnect did parts harbor 0:03:01.840 --> 0:03:07.639 a secret? We have useful scientific frameworks for understanding things 0:03:07.720 --> 0:03:12.080 like Parkinson's disease, or color perception or sensing temperature, but 0:03:12.160 --> 0:03:16.440 we don't really have any scientific framework for understanding what 0:03:16.560 --> 0:03:20.160 it means for the brain to have and to hold 0:03:20.480 --> 0:03:23.480 a secret. So that's what we're going to put into 0:03:23.480 --> 0:03:26.839 place today. Now, before we get there, let's start with 0:03:27.360 --> 0:03:32.000 Abraham Lincoln. In eighteen sixty, the young Lincoln emerged as 0:03:32.040 --> 0:03:35.400 the Republican part of The's candidate for president. And this 0:03:35.720 --> 0:03:40.360 was a surprise because he was relatively unknown compared to 0:03:40.440 --> 0:03:44.600 the seasoned politicians he was going up against, like William 0:03:44.640 --> 0:03:47.840 Seward and Sam and Chase and Edward Bates who are 0:03:47.880 --> 0:03:51.400 also vying for that nomination. But here's what Lincoln did 0:03:51.520 --> 0:03:57.000 after he won the presidency. He chose those people his rivals, 0:03:57.560 --> 0:04:02.360 to comprise his presidential cabinet. And not only them, but 0:04:02.440 --> 0:04:06.440 he also put in other people with totally different political 0:04:06.480 --> 0:04:10.440 ideologies from his. And that's how he formed his cabinet. 0:04:10.840 --> 0:04:17.120 The historian Doris Kerns Goodwin labeled this a team of rivals. Now, 0:04:17.200 --> 0:04:20.760 I've always loved this fact about Lincoln, first because it's 0:04:20.800 --> 0:04:24.800 actually quite sensible politically, but very few people do it. 0:04:24.800 --> 0:04:30.400 It's sensible because bringing together people with conflicting perspectives reflected 0:04:30.680 --> 0:04:33.480 his deep commitment to the Union and his focus on 0:04:34.000 --> 0:04:38.440 the bigger picture rather than personal grudges. He believed that 0:04:38.480 --> 0:04:42.120 the challenges of leading a divided nation through the Civil 0:04:42.160 --> 0:04:46.080 War required the best minds available, even if they disagreed 0:04:46.120 --> 0:04:48.760 with him or each other. So he got a spread 0:04:48.760 --> 0:04:51.880 of opinions this way. But the key thing is that 0:04:51.920 --> 0:04:57.560 the internal conflict gave strength to his presidency because no 0:04:57.600 --> 0:05:00.679 one gets to enjoy the delusion that they're there's a 0:05:00.760 --> 0:05:04.760 right and a wrong answer, But instead, every disagreement gets 0:05:04.920 --> 0:05:07.840 fought out, and sometimes a good solution is reached, and 0:05:08.080 --> 0:05:12.400 sometimes the problem festers and is revisited over and over. Now, 0:05:12.440 --> 0:05:15.600 the argument I forwarded in my book Incognito is that 0:05:15.640 --> 0:05:21.360 the brain fundamentally can best be understood as a team 0:05:21.720 --> 0:05:24.599 of rivals. So what does that mean. Well, it means 0:05:24.640 --> 0:05:28.880 that you are made up of many different neural networks, 0:05:29.040 --> 0:05:33.640 each of which sees different data and has its own goals. 0:05:34.240 --> 0:05:37.240 And this is why you can argue with yourself, or 0:05:37.800 --> 0:05:41.800 get mad at yourself, or try to control yourself to 0:05:41.839 --> 0:05:45.320 do something, or get angry at yourself, because you are 0:05:45.360 --> 0:05:50.680 not one thing, you are a multitude. I'll give you 0:05:50.720 --> 0:05:52.720 an example of this when it comes to how we 0:05:52.760 --> 0:05:56.640 make purchasing decisions, as in which restaurant to choose, or 0:05:56.640 --> 0:06:00.000 which clothing brand to buy, or what car should I purchase. 0:06:00.720 --> 0:06:05.159 In economics, we were taught about Homo economicus, the rational 0:06:05.200 --> 0:06:09.200 decision maker who maximizes gain and minimizes loss and is 0:06:09.279 --> 0:06:10.320 unswayed by emotion. 0:06:10.880 --> 0:06:13.839 But that is an idealized model. 0:06:14.240 --> 0:06:19.000 Real humans are emotional and inconsistent and easily influenced by 0:06:19.120 --> 0:06:24.120 context and branding, and the gap between theory and reality 0:06:24.440 --> 0:06:28.960 has given rise to the field of neuroeconomics. So consider this. 0:06:29.040 --> 0:06:32.480 I give you two courts of generic ice cream. One 0:06:32.560 --> 0:06:35.240 is priced lower than the other, and so the rational 0:06:35.360 --> 0:06:38.600 choice is pretty easy. But if I reveal the labels, 0:06:38.680 --> 0:06:41.560 let's say one is Ben and Jerry's one is Hoggendaws, 0:06:42.040 --> 0:06:46.479 your decisions might shift because all you're experiencing with their 0:06:46.600 --> 0:06:50.920 branding kicks in and your emotional predictions about how good 0:06:50.960 --> 0:06:54.440 something is likely to taste based on your past experiences, 0:06:54.520 --> 0:06:56.960 and maybe your sense of whether your friends like this 0:06:57.120 --> 0:07:00.680 or not, And all of this shifts the decision making 0:07:01.040 --> 0:07:03.840 one way or the other. What two decades of neuroimaging 0:07:03.880 --> 0:07:07.559 has shown is that our decisions about what to buy 0:07:08.120 --> 0:07:11.640 are driven by at least three major brain networks. You 0:07:11.720 --> 0:07:15.480 have one network along the midline that calculates the price 0:07:15.640 --> 0:07:19.840 or worth of something. Then you've got a separate network 0:07:19.920 --> 0:07:22.960 involved in emotion, mostly in the orbit or frontal cortex, 0:07:23.400 --> 0:07:27.480 and that anticipates how good or bad something will feel. 0:07:27.720 --> 0:07:30.760 Then you've got another network that's all about your choices 0:07:30.960 --> 0:07:34.840 in a social context, as in, what do your friends 0:07:34.840 --> 0:07:35.560 think about this? 0:07:35.680 --> 0:07:37.000 Is it cool or is it lame? 0:07:37.360 --> 0:07:40.640 And all of this tells us why companies don't just 0:07:40.840 --> 0:07:45.080 advertise with bullet points about their rational advantages. 0:07:45.400 --> 0:07:48.000 They spend millions of dollars on ads. 0:07:48.200 --> 0:07:51.280 To assure us that this is the best value and 0:07:51.480 --> 0:07:54.960 appeal to our feelings, and to assure us that everyone 0:07:55.040 --> 0:07:59.200 else loves this product as well. So, as a result 0:07:59.240 --> 0:08:03.840 of the complicate, hated voting of our neural parliaments, decisions 0:08:03.880 --> 0:08:07.480 aren't always straightforward to decode. So the next time you're 0:08:07.480 --> 0:08:11.240 thinking about your choice between ice cream brands or fast food, 0:08:11.280 --> 0:08:15.880 restaurants or car brands. Ask yourself, what is driving this decision? 0:08:16.040 --> 0:08:19.640 Is it price? Is it emotion? Is there a social 0:08:19.680 --> 0:08:23.240 influence on what I'm choosing? All these networks are fighting 0:08:23.320 --> 0:08:27.720 it out, each trying to have control in steering the 0:08:27.760 --> 0:08:30.520 ship of state. If you're interested in more about this, 0:08:30.600 --> 0:08:34.240 checkout episodes eight and nine. Now I mention all this 0:08:34.440 --> 0:08:39.000 now to illustrate this notion of battles in the brain. 0:08:39.400 --> 0:08:41.960 It's not just with buying decisions, but with all the 0:08:42.040 --> 0:08:44.920 choices you make in life. You have some networks that 0:08:45.040 --> 0:08:48.600 care about the short term in decision making, and you 0:08:48.640 --> 0:08:51.600 have some that care about the long term. You have 0:08:51.679 --> 0:08:55.400 networks that are monitoring and making predictions about the outside 0:08:55.440 --> 0:08:59.080 world and others that care about your inside world, the 0:08:59.160 --> 0:09:02.360 state of your body. Some of your networks provide a 0:09:02.440 --> 0:09:06.400 drive towards novelty and others towards familiarity, and these can 0:09:06.480 --> 0:09:09.520 both be active at the same time and having an 0:09:09.679 --> 0:09:13.520 arm wrestle. So think about these rivaling networks like a 0:09:14.160 --> 0:09:18.720 neural parliament. You're built of different political parties, all of 0:09:18.720 --> 0:09:22.000 whom love their country, but they just have different opinions 0:09:22.080 --> 0:09:25.360 about the best way forward. So this gives us a 0:09:25.840 --> 0:09:29.120 sense of these battling networks, and now I want to 0:09:29.200 --> 0:09:32.760 zoom in on something surprising. What you get out of 0:09:32.800 --> 0:09:36.960 a brain that is composed of multiple rivaling networks, You 0:09:37.040 --> 0:09:42.160 get a universe of secrets. The team of rivals framework 0:09:42.200 --> 0:09:46.000 allows us to address a mystery that would be inexplicable 0:09:46.280 --> 0:09:49.720 if we took the point of view of traditional computer programs. 0:09:49.960 --> 0:09:51.840 So let's come back to the question I asked at 0:09:51.880 --> 0:09:56.679 the beginning, what is a secret? Neurobiologically? And could your 0:09:56.720 --> 0:09:59.960 toaster keep a secret? Within the team of rivals framework, 0:10:00.320 --> 0:10:04.959 a secret is easily understood. It's the result of struggle 0:10:05.120 --> 0:10:08.360 between competing parties in the brain. One part of the 0:10:08.360 --> 0:10:12.480 brain wants to reveal something and another part does not 0:10:12.640 --> 0:10:16.199 want to. When there are competing votes in the brain, 0:10:16.320 --> 0:10:19.559 one for telling and one for withholding, that's a secret. 0:10:20.200 --> 0:10:24.120 If neither party cares to tell, that's merely a boring fact. 0:10:24.400 --> 0:10:27.000 And if both parties want to tell, that's just a 0:10:27.000 --> 0:10:30.960 good story. Without the framework of rivalry, we would have 0:10:31.000 --> 0:10:34.840 no way to understand a secret. The reason a secret 0:10:34.960 --> 0:10:40.080 is experienced consciously is because it results from a conflict. 0:10:40.120 --> 0:10:44.240 It's not business as usual, and so quite often our 0:10:44.360 --> 0:10:48.440 consciousness is called upon to deal with it. Now, the 0:10:48.520 --> 0:10:53.160 main reason not to tell a secret is aversion to 0:10:53.240 --> 0:10:57.560 the long term consequences. A friend might think ill of you, 0:10:58.040 --> 0:11:02.800 or a relationship might be revocably damaged, or a community 0:11:02.880 --> 0:11:07.920 might ostracize you. This concern about the outcome is evidenced 0:11:07.920 --> 0:11:10.360 by the fact that people are more likely to tell 0:11:10.400 --> 0:11:14.640 their secrets to total strangers. With somebody that you don't know, 0:11:15.240 --> 0:11:19.400 the neural conflict can be dissipated with none of the costs. 0:11:20.000 --> 0:11:25.040 And that's why strangers are occasionally so forthcoming on airplanes 0:11:25.160 --> 0:11:28.320 or in bars telling you all the details of their 0:11:28.760 --> 0:11:32.200 marital troubles. And we can see a modern twist on 0:11:32.320 --> 0:11:35.960 this ancient need to confess to strangers in the form 0:11:36.000 --> 0:11:40.439 of websites like postsecret dot com. This is a site 0:11:40.440 --> 0:11:45.600 where people go to anonymously disclose their confessions. Here are 0:11:45.760 --> 0:11:46.600 some examples. 0:11:47.080 --> 0:11:47.520 Quote. 0:11:47.640 --> 0:11:50.800 When my daughter was stillborn, I not only thought about 0:11:50.960 --> 0:11:54.120 kidnapping a baby, I planned it out in my head. 0:11:54.520 --> 0:11:58.320 I even found myself watching new mothers with their babies, 0:11:58.679 --> 0:12:01.520 trying to pick the perfect Now we don't know who 0:12:01.600 --> 0:12:05.640 posted this, but for that person something was released by 0:12:05.679 --> 0:12:09.320 confessing this. Here's another one. I was adopted, and my 0:12:09.400 --> 0:12:13.080 biggest fear is passing my biological father on the street. 0:12:13.600 --> 0:12:16.080 Or here's another one. I'm almost certain that your son 0:12:16.200 --> 0:12:19.280 has autism, but I have no idea how to tell you. 0:12:19.440 --> 0:12:22.280 There are tens of thousands of secrets on this website 0:12:22.840 --> 0:12:27.400 and why. It's because just telling your secret to the website, 0:12:27.440 --> 0:12:30.319 where you believe it will be read by other people 0:12:30.559 --> 0:12:35.680 strangers to you, is sufficient. And this reduction of tension 0:12:35.760 --> 0:12:39.280 by releasing a secret. This, I think also explains a 0:12:39.360 --> 0:12:43.920 staple in one of the world's largest religions, the confessional booth. 0:12:44.040 --> 0:12:48.040 You get something off your chest and without the consequences 0:12:48.040 --> 0:12:49.679 that might otherwise accrue. 0:12:49.760 --> 0:12:51.520 This same need to reveal. 0:12:51.200 --> 0:12:54.880 Ourselves might also shine light on the appeal of prayer, 0:12:55.080 --> 0:12:58.720 especially with religions that have a very personal God who 0:12:58.840 --> 0:13:03.120 lends an ear with undivided attention and non judgmental love. 0:13:03.520 --> 0:13:06.120 So why is a stranger or a website or a 0:13:06.160 --> 0:13:10.040 deity useful. It's because it's the act of telling the 0:13:10.080 --> 0:13:13.160 secret that matters. Things don't have to get solved, the 0:13:13.440 --> 0:13:16.880 cognitive tension just has to be reduced. We've all seen 0:13:16.920 --> 0:13:19.920 this that people often will vent a secret for its 0:13:19.960 --> 0:13:24.720 own sake, not as an invitation for advice. For example, 0:13:24.760 --> 0:13:27.400 somebody tells you a confession and you make the mistake 0:13:27.440 --> 0:13:31.600 of suggesting some obvious solution that only frustrates the other person, 0:13:31.920 --> 0:13:35.960 because all they really wanted was to tell to reduce 0:13:36.000 --> 0:13:39.920 the neural tension. The act of telling the secret was 0:13:40.000 --> 0:13:43.520 the solution. Now an open question is why the receiver 0:13:43.800 --> 0:13:47.440 of the secrets has to be human or human like 0:13:47.480 --> 0:13:50.160 in the case of deities. If you tell your secret 0:13:50.320 --> 0:13:53.640 to a wall or a lizard or a goat, that's 0:13:53.679 --> 0:13:57.000 going to be a lot less satisfying. Now, one thing 0:13:57.040 --> 0:13:59.720 that strikes me is interesting in this regard is the 0:13:59.800 --> 0:14:03.439 right popularity of AI therapist bots. 0:14:03.679 --> 0:14:05.280 Where will lees sit in. 0:14:05.280 --> 0:14:09.640 The hierarchy of human to non human I think it'll 0:14:09.640 --> 0:14:12.640 be pretty close to a person or a deity. I 0:14:12.679 --> 0:14:15.160 suspect that in the future we'll be pretty happy to 0:14:15.240 --> 0:14:19.320 let our secrets out to our AI therapist, But only 0:14:19.400 --> 0:14:22.720 if you're convinced about the security of the company. Is 0:14:22.760 --> 0:14:26.520 it just a matter of time before the FBI says 0:14:26.560 --> 0:14:29.880 to the tech company, Hey, we can subpoena your therapy 0:14:29.960 --> 0:14:34.360 history under special circumstances. So it's still to be seen 0:14:34.480 --> 0:14:37.800 how much people will unload on their bots because the 0:14:37.880 --> 0:14:41.040 key with unloading your secrets is to get the cognitive 0:14:41.040 --> 0:15:00.040 benefit without the social consequences. Okay, so I've been and 0:15:00.160 --> 0:15:03.640 referring to this cognitive load of keeping a secret. But 0:15:03.680 --> 0:15:06.720 the question is why do we have difficulty? Why isn't 0:15:06.720 --> 0:15:10.600 it easy to keep a secret? Here's why, because keeping 0:15:10.680 --> 0:15:17.000 a secret requires ongoing mental effort to monitor your speech 0:15:17.120 --> 0:15:20.520 and actions. You have to make sure that the hidden 0:15:20.560 --> 0:15:25.280 information isn't accidentally revealed. Even if this is happening at 0:15:25.280 --> 0:15:30.000 a subconscious level, it's a state of constant vigilance to 0:15:30.120 --> 0:15:32.920 keep from blurting out the secret. So how do you 0:15:33.000 --> 0:15:36.440 measure this? So some years ago, a scientist named Sean 0:15:36.520 --> 0:15:40.600 Spence and his colleagues interviewed participants on what activities they 0:15:40.600 --> 0:15:43.160 had done the previous day, and then they put them 0:15:43.360 --> 0:15:46.960 in the brain scanner fMRI. These people were given questions 0:15:46.960 --> 0:15:49.560 about what they did and they were given two buttons 0:15:49.680 --> 0:15:52.760 yes or no. Now, on each round, they were given 0:15:52.840 --> 0:15:55.480 either a red light or a green light to tell 0:15:55.520 --> 0:15:59.480 them whether they should lie or whether they should tell 0:15:59.520 --> 0:16:02.680 the truth on that trial. So the first thing the 0:16:02.680 --> 0:16:05.200 researchers noted is that it always takes a little bit 0:16:05.240 --> 0:16:07.720 longer to lie, about a fifth of a second longer, 0:16:07.720 --> 0:16:10.680 and this is because you are taking the answer that 0:16:10.720 --> 0:16:13.800 you already know the true answer, and you're squelching that. 0:16:14.600 --> 0:16:19.000 So they demonstrated that this squelching of the truth responses 0:16:19.520 --> 0:16:22.360 activates a part of the prefrontal cortex, a part that's 0:16:22.640 --> 0:16:26.600 down load near the side. It's called the ventrilateral prefrontal cortex. 0:16:27.120 --> 0:16:30.280 The thing to appreciate is that this region becomes active 0:16:30.800 --> 0:16:34.080 whenever you need a suppressive behavior that you would normally 0:16:34.240 --> 0:16:36.800 just go with, in this case telling the truth. And 0:16:36.920 --> 0:16:39.840 other brain errors are involved too. In a study bi 0:16:39.960 --> 0:16:42.920 Langeleman and colleagues the next year, participants went into a 0:16:42.960 --> 0:16:45.880 scanner and they saw a playing card on the screen 0:16:45.960 --> 0:16:47.480 and they were asked to remember it. 0:16:48.160 --> 0:16:49.320 Then they were shown. 0:16:49.080 --> 0:16:51.640 A series of cards and they were asked was that 0:16:51.760 --> 0:16:52.720 your card or not? 0:16:53.480 --> 0:16:57.560 And they were sometimes instructed to lie. And here's the key. 0:16:58.040 --> 0:17:01.040 When they lied, researchers saw a lot of activity in 0:17:01.080 --> 0:17:04.359 an area called the anterior singulate cortex, which is a 0:17:04.400 --> 0:17:09.159 region that detects conflict between other brain areas. So in 0:17:09.200 --> 0:17:12.159 both these studies, people were just saying yes or no 0:17:12.359 --> 0:17:15.200 to lie or not lie. But in the next study 0:17:15.400 --> 0:17:18.200 by Spence and colleagues, they wanted to see what happened 0:17:18.240 --> 0:17:21.520 in the brain when people are forced to get more 0:17:21.840 --> 0:17:25.359 imaginative when they go beyond yes or no answers to 0:17:25.480 --> 0:17:28.199 make up a new story. So imagine I ask you 0:17:28.840 --> 0:17:32.359 where were you on the evening of February twenty second, 0:17:33.000 --> 0:17:34.639 and you can figure out the answer that. 0:17:34.760 --> 0:17:36.600 Let's say you were at a great party that night. 0:17:37.000 --> 0:17:40.120 But imagine that you lie to me and you say, oh, 0:17:40.240 --> 0:17:43.480 I met my friend for a quiet movie on Netflix 0:17:43.480 --> 0:17:46.080 that night. Now, in order to do this, in order 0:17:46.160 --> 0:17:49.679 to lie, you have to think of the true response 0:17:49.720 --> 0:17:53.679 and suppress that like we saw before, but also you 0:17:53.800 --> 0:17:56.400 then have to make something up. So you're now doing 0:17:56.440 --> 0:18:00.120 two things. You're suppressing the true answer, which cranks the 0:18:00.119 --> 0:18:04.080 the ventralateral prefrontal cortex like we saw, and then you 0:18:04.160 --> 0:18:07.119 need to cook up the lie, and that activates a 0:18:07.160 --> 0:18:11.919 different region than dorsilateral prefrontal cortex. The dorsilateral area cranks 0:18:12.000 --> 0:18:15.440 up when you generate something new, like a new story, 0:18:15.840 --> 0:18:17.720 and especially if this is the first time that you're 0:18:17.720 --> 0:18:20.200 making up that story. And we see other areas too, 0:18:20.400 --> 0:18:24.199 like the anterior cingulate cortex, which reflects internal conflict. And 0:18:24.240 --> 0:18:28.479 we see another part of the prefrontal cortex, the ventromedial region, 0:18:28.720 --> 0:18:32.280 which cranks up when you're trying to regulate your emotions. 0:18:32.960 --> 0:18:37.800 So covering up the truth is a high energy endeavor 0:18:37.840 --> 0:18:41.560 for the brain. We never see areas where there's more 0:18:41.600 --> 0:18:43.359 activity when you tell the truth. 0:18:43.880 --> 0:18:46.560 There's only more activity when you're lying. 0:18:47.119 --> 0:18:50.080 So the idea that it's easier to tell the truth 0:18:50.520 --> 0:18:54.399 holds as a rule in life, presumably because it holds 0:18:54.400 --> 0:18:58.440 as a rule in the brain. And if the cooked 0:18:58.520 --> 0:19:01.960 up story doesn't go so per we end up painting 0:19:02.000 --> 0:19:05.720 ourselves into a corner, which brings with it lots more 0:19:06.240 --> 0:19:10.320 brain energy expenditure. And this observation is one that the 0:19:10.440 --> 0:19:15.480 Scottish poet novelist Sir Walter Scott immortalized in his poem 0:19:15.640 --> 0:19:18.360 Marmion in eighteen oh eight. This is where he penned 0:19:18.400 --> 0:19:22.280 the immortal line, Oh what a tangled web we weave 0:19:22.760 --> 0:19:26.679 when first we practice to deceive. He was pointing to 0:19:26.880 --> 0:19:30.560 a common problem that arises when we make up a 0:19:30.600 --> 0:19:33.159 lie to cover a secret, and then that leads to 0:19:33.200 --> 0:19:35.879 another necessary lie, which leads to another, and now you 0:19:35.920 --> 0:19:39.080 have to keep track of this whole web of lies 0:19:39.480 --> 0:19:42.440 to try to keep your story consistent, which can lead, 0:19:42.600 --> 0:19:45.639 as Sir Walter Scott may have intuited, to a high 0:19:45.760 --> 0:19:50.439 cognitive load. And cognitive load matters because it equates to 0:19:50.560 --> 0:19:55.080 emotional stress. We all know from experience that holding on 0:19:55.160 --> 0:19:59.199 to a secret creates anxiety, and often these bad feelings 0:19:59.440 --> 0:20:03.560 increase our urge to confess or share the secret to 0:20:03.640 --> 0:20:08.160 relieve the burden. So secret keeping requires a lot of work. 0:20:08.680 --> 0:20:12.240 But what I want to highlight is the double edged 0:20:12.440 --> 0:20:17.639 nature of the secret because, perhaps surprisingly for better or worse, 0:20:18.119 --> 0:20:21.159 the ability to keep a secret is one of the 0:20:21.200 --> 0:20:26.000 main drivers of the shape of our species and society. Now, 0:20:26.040 --> 0:20:29.359 we can talk all day about the downsides of keeping 0:20:29.400 --> 0:20:32.520 secrets from one another, but in fact, the ability to 0:20:32.600 --> 0:20:36.200 keep secrets seems to have evolved many millions of years 0:20:36.240 --> 0:20:41.080 ago as a survival mechanism, as it turns out, concealing 0:20:41.119 --> 0:20:46.520 information about food sources or about shelter or defensive strategies. 0:20:46.680 --> 0:20:50.080 This is often what made the difference between life and death. 0:20:50.480 --> 0:20:54.359 And it's not just humans who practice deception. Other primates 0:20:54.440 --> 0:20:57.560 do this as well. Now I'm not talking about deception 0:20:57.720 --> 0:21:01.879 like using camouflage. Instead I'm talking thinking about active, clever 0:21:02.119 --> 0:21:06.480 deception that requires theory of mind, in other words, the 0:21:06.520 --> 0:21:10.440 ability to step into the perspective of another to understand 0:21:10.480 --> 0:21:13.320 what they know and don't know. It turns out that 0:21:13.520 --> 0:21:16.680 only primates seem to do this, and in fact they're 0:21:16.840 --> 0:21:20.400 constantly doing things to deceive one another. On this note, 0:21:20.440 --> 0:21:23.480 here's a short clip from my interview with Max Bennett 0:21:23.480 --> 0:21:25.520 from last year, who wrote a great book called A 0:21:25.560 --> 0:21:29.760 Brief History of Intelligence. And here's Max describing an example 0:21:29.880 --> 0:21:32.040 of deception in chimpanzees. 0:21:32.480 --> 0:21:35.760 So you can see non human apes do things like 0:21:36.119 --> 0:21:38.800 they will hide transgressions from other people to try and 0:21:38.840 --> 0:21:42.080 prevent themselves from getting in trouble. There's this famous study 0:21:42.440 --> 0:21:45.240 that I love by Emil Menzel. I think it was 0:21:45.240 --> 0:21:48.679 in the seventies where he put two chimpanzees in the 0:21:48.720 --> 0:21:52.280 sort of one acre forest and he showed the location 0:21:52.400 --> 0:21:56.520 of treats to one of the chimpanzees named Belle, and 0:21:56.880 --> 0:22:00.119 she initially would share the treat with another chimpanze he 0:22:00.160 --> 0:22:03.280 named Rock, but then Rock started just stealing the treat 0:22:03.320 --> 0:22:06.199 from her. So what she started doing is when she 0:22:06.280 --> 0:22:08.520 knew the location of the treat, she would wait for 0:22:08.560 --> 0:22:10.400 a rock to look away, and then she would run 0:22:10.440 --> 0:22:13.720 over and grab it. So then rock in response to this, 0:22:13.920 --> 0:22:17.199 decided to pretend to look away so that when she 0:22:17.280 --> 0:22:19.800 started running, then he would turn around and run. Then 0:22:19.800 --> 0:22:21.800 in response to this, what she would do is she 0:22:21.800 --> 0:22:24.439 would pretend to run in the wrong direction, lead him 0:22:24.480 --> 0:22:26.040 to the wrong place, and then run back. 0:22:26.359 --> 0:22:30.520 So the tricky deceptive capacity we have to not spill 0:22:30.600 --> 0:22:37.360 the beans enhances the chances of individual survival. Now, when 0:22:37.359 --> 0:22:40.600 we zoom in on humans and study them very carefully, 0:22:40.720 --> 0:22:44.280 what we find is that keeping secrets and more generally, 0:22:44.640 --> 0:22:49.200 lying is a cognitive development in children. In other words, 0:22:49.240 --> 0:22:51.400 And first young children. 0:22:51.080 --> 0:22:52.240 Don't know how to lie. 0:22:52.720 --> 0:22:55.440 And then they hit a milestone one day, let's say 0:22:55.440 --> 0:22:57.919 between two and four years old, and they get a 0:22:57.960 --> 0:23:02.280 great idea, maybe they can assert something that's not true 0:23:02.760 --> 0:23:06.800 and maybe the other person won't know. So they carefully 0:23:07.200 --> 0:23:11.800 float this trial balloon and sometimes it works. Suddenly they 0:23:11.840 --> 0:23:16.320 have eaten the cooky but avoided punishment, so they start 0:23:16.359 --> 0:23:19.399 to lie. As soon as they develop theory of mind, 0:23:19.480 --> 0:23:23.240 they start to understand that their thoughts and minds are 0:23:23.320 --> 0:23:26.320 separate from those of their parents. They also begin to 0:23:26.320 --> 0:23:30.720 realize that people aren't perfect mind readers, so the child 0:23:30.760 --> 0:23:34.680 can say something that isn't true, and miraculously the other 0:23:34.800 --> 0:23:39.760 person doesn't always know. Obviously, sometimes the child doesn't get 0:23:39.800 --> 0:23:41.600 away with it, and so they conclude that they need 0:23:41.640 --> 0:23:45.040 to work even harder to cook up better fabrications that 0:23:45.160 --> 0:23:47.920 might fool the other person. And for this they need 0:23:47.960 --> 0:23:51.320 to get better and better at stepping into the other 0:23:51.400 --> 0:23:55.280 person's shoes to understand what that person might fall for. 0:23:55.840 --> 0:23:59.000 So children start to lie more frequently as they get 0:23:59.000 --> 0:24:01.639 older and they get better at lying. They learn to 0:24:01.760 --> 0:24:05.520 match their facial expressions and tone of voice to what 0:24:05.760 --> 0:24:09.120 they're saying, and they shape their lies based on their 0:24:09.200 --> 0:24:12.679 assumptions of what the other person may or may not know. 0:24:13.000 --> 0:24:15.920 And lying sucks, especially when it's in your own kids. 0:24:15.960 --> 0:24:19.520 But I'll just mention that some researchers view lying as 0:24:19.560 --> 0:24:24.720 an important developmental stage that indicates early intelligence. So while 0:24:24.760 --> 0:24:27.240 none of us appreciate being lied to by our kids 0:24:27.359 --> 0:24:30.600 or having secrets kept from us by our colleagues, it's 0:24:30.720 --> 0:24:35.879 one of the signatures of the extraordinarily intelligent primate brain. 0:24:36.359 --> 0:24:39.040 And in fact, when you look across human history, the 0:24:39.119 --> 0:24:43.320 thing that becomes clear is that secrets quickly expanded beyond 0:24:43.359 --> 0:24:47.879 the individual level to the group level. So trust within 0:24:48.000 --> 0:24:52.359 small groups usually depended on the ability to keep certain 0:24:52.440 --> 0:24:56.400 knowledge hidden from outsiders, and by the way, keeping internal 0:24:56.400 --> 0:25:00.480 group secrets has the added benefit of thought during a 0:25:00.560 --> 0:25:05.199 sense of belonging in mutual protection and secrets have always 0:25:05.200 --> 0:25:09.399 been a key part of military strategy. The immortal book 0:25:09.480 --> 0:25:12.920 The Art of War by Sun Su paints a picture 0:25:13.080 --> 0:25:19.560 of deception and secrecy as absolutely essential for successful warfare, 0:25:20.200 --> 0:25:23.320 and more generally, secrets have always been a lever for 0:25:23.400 --> 0:25:29.399 power within larger groups. As civilizations grew, secrets became pervasive 0:25:29.720 --> 0:25:34.160 wherever people maintained and exercised power. You see this all 0:25:34.200 --> 0:25:38.919