Why do we lie?

MOLLY BLOOM: Hi, friends. Before we get started, we just wanted to let you know that Mark, Sanden, and I are going to be debuting our new live show really soon. It's called Your Brain is Magic. We'll be at the Fitzgerald Theater in Saint Paul, Minnesota on October 27 at 2:00 PM.

There's a game show, magic tricks, and even a little bit of dancing. You can find out more and get your tickets at brainson.org/events. Hope to see you there.

SPEAKER: You're listening to Brains On, where we're serious about being curious.

SPEAKER: Brains On is supported in part by a grant from the National Science Foundation.

GARY: Lie, we're ready for you on set.

LIE: Hey, thanks, Gary. And Gary.

GARY: What is it, Lie?

LIE: I really want to just say thanks for being here today, and for being part of this commercial shoot. I think it's the best way to set the record straight about lying.

GARY: Happy to help.

LIE: And Gary.

GARY: Yeah.

LIE: Nice shirt.

GARY: Thanks, Lie. My grandma got this for me. I wasn't sure if the neon pink pineapples were too much on top of the zebra print, but yeah, I like it too. OK. See you on the set and a few.

LIE: Bye, Gary. What a horrible shirt.

[MUSIC PLAYING]

MOLLY BLOOM: You're listening to Brains On from American Public Media. I'm Molly Bloom, and my co-host today is Elena from Edina, Minnesota. Hi, Elena.

ELENA: Hi, Molly.

MOLLY BLOOM: You wrote into us with the question that this whole episode is based on. Can you tell us what that question was?

ELENA: Why do we lie?

MOLLY BLOOM: So what made you curious about lying?

ELENA: Well, I really wanted to know why our brain would lie if we could just tell the truth.

MOLLY BLOOM: Yeah, like why we do that

ELENA: Yeah.

MOLLY BLOOM: It's a really good question. So why do you think we lie?

ELENA: Maybe because in some situations, it's easier to, instead of telling the truth.

MOLLY BLOOM: So when would you say that line is wrong?

ELENA: I would say it's wrong if it's something bigger than how is your day, or was that a good meal. Because that could actually affect someone bigger than making them feel good.

MOLLY BLOOM: And when would you say lying is like maybe OK?

ELENA: Like I said, probably, like how is your day. You could say, well, instead of OK. Or like I liked that pizza when you didn't really like it.

MOLLY BLOOM: Yeah. Because maybe in the case of how's your night, maybe you just don't want to tell them how your day was. You don't want to get into It

ELENA: Yeah.

MOLLY BLOOM: Maybe you're too tired to talk about it. It's easier to just say, it was wonderful, rather than all the things that happened in that day. So are there times when you lie?

ELENA: Yeah. I'm pretty sure everybody does. I don't know anybody or think anybody has ever not lied.

MOLLY BLOOM: I think you're right. So I'm pretty sure that we all know what a lie is. But it's kind of amazing when you stop and think how many different kinds of lies there are.

ELENA: You can lie by making something up.

MOLLY BLOOM: Or you can lie by leaving something out.

ELENA: You can exaggerate things.

MOLLY BLOOM: Or you can change the order that things happened in.

ELENA: There are big lies.

MOLLY BLOOM: Like if I said recently, that I won an Oscar. Oh, thank you. Thank you. You're too kind.

ELENA: And little lies, like if I said, yes, Molly, I love the cheese and pickle sandwich you made me.

MOLLY BLOOM: You didn't like the sandwich? Note to self, next time, make Elena a--

ELENA: Goat cheese and prosciutto sandwich.

MOLLY BLOOM: Got it. Prosciutto and goat cheese, on it. Anyway, we, humans, have clearly come up with a lot of ways to hide the truth.

ELENA: But why? Why do humans have so many ways to lie?

MARK: Molly, Elena.

MOLLY BLOOM: Oh, hey, Mark. What's up?

MARK: This just got dropped off in our daily postal pelican package.

MOLLY BLOOM: Pelicans deliver our packages. It's pretty practical. So what is it, Mark?

MARK: It looks like a DVD. And it has a note attached. It says, I heard you were doing an episode about me. I think it's only fair you let me speak for myself. Signed, A Lie. A lie?

MOLLY BLOOM: I'll put it on.

[MUSIC PLAYING]

SPEAKER: Liar, liar, pants on--

LIE: You've heard the chants. You know the stories.

PINOCCHIO: Who [INAUDIBLE], Geppetto. I swear, it wasn't me.

GEPPETTO: Then what's with that nose, Pinocchio?

SPEAKER: But do you know--

LIE: Me? Hi. I'm a lie. And this is my neighborhood. Yeah. I'm just like you.

PAUL: Hello, Lie.

LIE: Oh, hey, Paul. Great haircut.

PAUL: Thanks, buddy.

LIE: I hate that haircut. But you know humans evolved to be social creatures. You guys don't have a lot of natural defenses. So you found out you were stronger together, working as a group towards common goals. Like finding food and not being eaten.

GLORIA: Hi, Lie.

LIE: Oh, hey Gloria. Thanks again for dropping that casserole off the other night. So good.

GLORIA: Oh, my pleasure. See you around.

LIE: It was disgusting. Any [INAUDIBLE]. Being part of this group was key to survival. So you humans are hardwired to care deeply about what other people think of you. So you know, sometimes, a little lie here or there can smooth the rough edges of social interaction. Like nobody wants this-- hey, Roger.

ROGER: Oh, hey, Lie. What's up?

LIE: Your Christmas decorations are so tacky.

ROGER: You told me you loved the 3D light sculpture of Rudolph and Santa doing the hula. Now, I feel sad, and angry. And I don't think we can be friends anymore.

LIE: See, if everyone did that all the time, society would be a mess. People would get into fights, throw fits, stop cooperating with each other, and lose all of the excellent advantages that come with teamwork.

Now, I'll admit, we, lies, can be used for more nefarious purposes. I'm talking about lying to hurt someone's feelings to get someone else in trouble, or lying to cover up something you did that you knew was wrong.

Like telling Joni that the rabbits must have eaten all the carrots in her garden. When in fact, it was you who stole the carrots in order to bake your blue ribbon winning carrot muffins. You would never do that.

JONI: Hello, Lie.

LIE: Hello, Joni. You see, if Joni found out you were lying, people would know that you did something that went against the rules of your little social group. And that wouldn't be great.

So take it from me-- a lie. I've been helping humans get along for years. I'm part of your community. Just don't let me get out of hand.

JONI: My tomatoes are gone. Lie, come back here.

LIE: Oh, got to go. I'm making tomato sauce tonight. I'm a lie. And I approve this message.

SPEAKER: Ba ba ba ba ba ba ba ba ba ba Brains On.

MOLLY BLOOM: Well let's see if your ears will deceive you today.

SPEAKER: Mystery sound.

MOLLY BLOOM: It's time for the mystery sound. Here it is.

[MYSTERY SOUND]

MOLLY BLOOM: What do you think? Any guesses?

ELENA: Maybe it's like some birds chirping in a rain forest.

MOLLY BLOOM: Excellent guess. Well, we'll be back with another chance to guess a little later in the show.

SPEAKER: Brains, brains, brains on.

MOLLY BLOOM: None of us are born knowing how to lie.

ELENA: Just like walking and talking and reading and writing, and pretty much everything else, we have to learn to do it.

MOLLY BLOOM: And even though it seems like a bad habit to pick up, learning to lie is actually a really important step in a child's development.

ELENA: Here to explain is our pal, Sanden Totten.

SANDEN TOTTEN: To understand how we learn to lie, let's start with a story. This is a version of a story scientists tell kids to see if they're able to lie yet. Trust me, it'll make sense in a minute.

So imagine there's a kitchen. And on the counter, there's the biggest, chunkiest chocolate chip cookie you've ever seen. And into the kitchen walks Bob.

BOB: Hello. Oh, what have we here? A giant cookie.

SANDEN TOTTEN: Bob wants to eat that cookie.

BOB: I shall name it Chip Pea McCookie Face. And it shall be my snack. Oh, but wait. I can't eat a cookie without milk. That would be like eating a hot dog without a bun, or spaghetti without watermelon. They just go together. Oh, man. Out of milk.

SANDEN TOTTEN: So Bob heads to the store.

BOB: A BRB chip. I mean, Mr. McCookie Face.

SANDEN TOTTEN: Meanwhile, TV chef Kathy from cooking with Kathy enters the picture.

KATHY: Oh, that's where I left you, my perfect chocolate chip creation. I call it Queen Chocolina. And it rules the land of Chipperdonia. Now let's put you in the fridge for safekeeping, your highness. There you go. Oh, time for my show. BRB, Queen Chocolina.

SANDEN TOTTEN: Kathy leaves. And right after that, Bob is back.

BOB: Mr. McCookie Face, I've got good news. The milkman cometh. Ha ha ha. Oh, wait. Mr. McCookie Face isn't on the counter?

SANDEN TOTTEN: OK, pause right here. I'm going to ask a seemingly obvious question. It's the same question scientists ask young kids to see if they have what it takes to lie. The question is, does Bob know where the cookie is?

I mean, no, right? He wasn't there when it was moved. We know it's in the fridge. But Bob doesn't know what we know. But here's the interesting thing. A lot of really young kids, like before age three or so, they'll say, yeah, Bob knows where the cookie is. He knows it's in the fridge.

You see, they think because I know where the cookie is, everyone must know where the cookie is. Kids under the age of three or so think we all have the same information all the time. But the older kids, they know that's not true. They know we all have different brains and we each different things. This idea that it's possible to know things that other people don't is called theory of mind.

PENNY VAN BERGEN: So when you have this theory of mind it means that you understand what's in somebody else's mind, and you understand that they may have different beliefs and thoughts and emotions to yourself.

SANDEN TOTTEN: That's Penny Van Bergen. She teaches educational psychology at Macquarie University in Sydney, Australia. She says no one is born with a theory of mind. We develop the skills somewhere between ages two and four.

Before that, young kids and babies go around thinking anything they know or feel, everybody knows or feels. But once they realize that's not true, something big happens.

PENNY VAN BERGEN: When you understand that other people have different thoughts to yourself, different emotions, different beliefs, then you also work out that you can trick them. You can tell a lie to them, and they might believe that lie even though that it's not true.

SANDEN TOTTEN: And that's when lying starts. Now, don't get me wrong. These aren't good lies. The stories are outlandish. The characters are unbelievable. The plots have so many holes. Like I didn't eat the cake. I don't know how the cake got on my face and my hands. Must have fallen from the sky when it was raining cake. Bad lie-- see.

But soon, kids get better at it. The lies become more convincing and harder to spot. But luckily, Penny says something else starts to happen around that same time that keeps kids from lying all the time.

PENNY VAN BERGEN: Also, what happens at same time is moral development occurs. And so even though you have the ability to lie, you become much better at distinguishing when it's appropriate to lie, and when it might hurt other people to lie.

SANDEN TOTTEN: Kids start developing morals. That means kids start learning the difference between right and wrong. They also learn to empathize with others. That means they can understand when someone else is feeling sad or happy. And it makes them feel happy or sad too. And you know what makes this moral development possible? Once again, it's theory of mind.

PENNY VAN BERGEN: So suddenly, having the understanding that other people have different emotions sets you up really well to develop morally, and to think empathically. And so understanding that somebody else might be really sad about something is really important for being able to empathize with them, and to kind of try to comfort them.

SANDEN TOTTEN: So the same mental skill that gives kids the ability to lie also, eventually, gives them the ability to see the world through someone else's eyes. And it may take some time. But with the right guidance, kids will realize lying often hurts people.

And since they, themselves, don't like being lied to, they can imagine other people won't like it either, which is pretty cool, right?

BOB: Well, that's all well and good, but what about Mr. McCookie Face? Did it just disappear?

KATHY: Oh, you mean, Queen Chocolina. It's in the fridge. I was going to eat it all by myself. But I can tell you were really excited to taste my wonderful confectionery masterpiece. If I was in your shoes, I'd be sad. How about we split it?

BOB: You'd do that for me? Oh, thank you, Kathy. Oh, and I brought milk.

KATHY: Perfect. Cheers, Bob, to theory of mind.

BOB: To theory of mind.

SANDEN TOTTEN: Well, back to you, Molly and Elena.

MOLLY BLOOM: We're working on an episode all about why we kind of like scary things.

ELENA: Like monsters-- ah, scary. But also, kind of fun scary.

MOLLY BLOOM: And we have a question for you. What about a scary switcheroo? Monsters are the ones who usually get to do all the scaring. But how would you scare a monster?

ELENA: Tell us that brainson.org/contact.

MOLLY BLOOM: Elena, how would you scare a monster?

ELENA: I would probably hide behind the monster and jump up and yell boo.

MOLLY BLOOM: And see if it's got startled. That's a really good plan. I think I would-- I don't know. I feel like monsters might be like not as into like bright, shiny things. Like they might like the darks. Maybe I would shine like a rainbow lamp that glittered at them. And they would be so terrified by this bright rainbow glittery thing that they would run away.

ELENA: Yeah. That's a good plan.

MOLLY BLOOM: It's a little more convoluted than your plan, which was very elegant and simple. So we want to hear your ideas too, listeners. Send them to us at brainson.org/contact.

ELENA: That's also where you can send in your questions, your drawings, your mystery sounds.

MOLLY BLOOM: That's where we got this magnificent question from Cathy.

CATHY: Do we still get sponges from the sea? Or are they made out of something different? I hope we don't get them from the sea anymore. That's awful.

ELENA: Stay tuned for the answer during the Moment of Um, at the end of the show.

MOLLY BLOOM: After that, you'll hear the latest listeners to join the Brain's honor roll.

ELENA: Keep listening.

You're listening to Brains On. I'm Elena.

MOLLY BLOOM: And I'm Molly. We've been talking about why we lie, and it's pretty complicated. We know we're supposed to tell the truth.

ELENA: But sometimes, that's difficult. Our pal, Danny Weinkauf, has been keeping a list of times people feel they need to lie. And here's that list in song form. It's called Sometimes We Lie.

[MUSIC PLAYING] Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometime we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Well I don't know if I can explain the things that happened in our brains. Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie.

At the age of two years old, many people start to lie. And it just to make their parents smile. Then as they grow older and the years start passing by, the lies get more complex and it fib with style.

Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Well, I don't know if I can explain the things that happen in our brains. Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie.

We may say the things you want to hear to spare somebody's feelings, trying to be polite in what we say . But some of us are narcissists, inflating our self image, manipulating you to get away.

You don't have to be a swindler or a con man. It's normal for a human being to lie. Scheming and dishonesty are human. So don't believe me, I'm just a normal guy.

Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Sometimes we lie. Well, I don't know if I can explain the things that happen in our brain. Sometimes we lie. Sometimes we lie. Sometimes we lie.

MOLLY BLOOM: When he's not writing songs about lying, you can find Danny Weinkauf playing bass for the band, They Might be Giants. Find more of Danny's original songs at dannyweinkauf.com.

All right. Now that our ears have been delighted by the sweet sounds of that song, let's go back to another sonic treat-- the mystery sound. Let's hear it again.

[MYSTERY SOUND]

ELENA: I still think it sounds like a bird chirping, but maybe it's like a bird chirping to another bird. The other bird's chirping back.

MOLLY BLOOM: They're chatting, having a little chat.

ELENA: Yes.

MOLLY BLOOM: I love it. Well, let's hear the answer.

DONNA KEAN: The sound that you just heard was a capuchin monkey giving a predator alarm call in the jungle of Argentina. A capuchin monkey may sometimes use this call to lie to other monkeys when they are competing for food like peanuts or bananas to scare the other monkeys away. So that it can get some food for itself.

MOLLY BLOOM: So I'm going to say you were close. It was animals communicating with each other, totally right. But not a bird, a monkey.

ELENA: I'm very surprised because I didn't know monkeys could sound like that.

MOLLY BLOOM: Yeah. It's a very specific call they make. So Donna Kean, who we just heard, she studies how monkeys talk to each other at the University of Stirling in Scotland. Usually, capuchin monkeys use this call as a predator warning.

The call means, look out for that snake, it might eat you. But sometimes, monkeys also use this same call to trick each other.

DONNA KEAN: When they make this call when they're competing for food, it causes the other monkeys to run away, so that the monkey who made the call can run in and grab some food for himself.

[ALARM CALL]

DONNA KEAN: So one explanation would be that the monkey thinks OK, I can't get any access to this food. If I pretend that there's a predator, then the other monkeys will think that there's a snake or something like that nearby. And they'll run away. And then I can get some food. So that would be really complex thinking.

The other explanation would be, see all the big strong monkeys are feasting on some food and as a small, maybe quite weak monkey, you're not really getting any access, maybe one time you just make the alarm call. It's just random. And you notice that everyone runs away and you get some food.

You might not know why they've run away. You don't know that they think there's a predator there. You just know when I make this call, they leave. And this is perfect for me because then, I can get some food.

MOLLY BLOOM: So we don't know if capuchins know they're tricking the other monkeys or if they're making this call more randomly. But either way, if you imagine that you're another capuchin monkey, you want to pay attention to all alarm calls, even the ones that could be fibs.

DONNA KEAN: If there was a predator there, that's obviously very, very dangerous. It's really important that you avoid that predator because they could seriously injure you or harm you. Even if as feeding competition and you think well, this monkey could be lying, it probably is still beneficial for you to run away just in case. Because if you don't run away, it could be really bad for you, the monkey.

SPEAKER: (SINGING) Brains on.

MOLLY BLOOM: So for monkeys, it's very hard to tell a lie from the truth. And before you go patting yourself on the back, humans can only tell if someone is lying about half of the time. Can we make artificial intelligence better at detecting lies than we can?

ELENA: We've asked Angela Evans to weigh in. She's a psychologist at Brock University in Canada. Welcome, Angela.

ANGELA EVANS: Thank you very much for having me, Elena.

ELENA: Is there ways to, sometimes, know if someone's lying, like if they're talking differently or something like that?

ANGELA EVANS: It depends how you're looking at how they're talking at differently. So one way we can look at it is the types of things that they say. Lie tellers are less likely to use something called personal pronouns. So those are words like I or me. So they want to distance themselves from the lie. So they're less likely to refer to themself.

They also tend to take longer to respond in order to tell the truth you just think about what happened and you tell the truth. But to tell a lie, you think about the truth, then you have to stop yourself from saying the truth.

You have to hold the truth in memory, and then come up with some alternative statement. And all of that takes time for our brain to do. So usually, it takes a little bit longer for people to tell a lie than tell the truth.

MOLLY BLOOM: Are there things like with someone's eyes or smile that could be like a tell for if they're lying?

ANGELA EVANS: So some people think that eyes are kind of the window to the truth. During a lie, it's often reported that people will blink more often or avoid eye contact or that there's pupil dilation. And this is sometimes true for lie tellers. But it's also a physiological reaction.

And this physiological reaction of blinking and pupil dilation is also associated with nervousness. So when people are nervous, they're more likely to blink, their pupils are going to dilate, they're probably less likely to make eye contact. So it's really hard to conclude that someone's actually telling a lie if they're avoiding eye contact.

Some people also think looking up into the left means someone is telling a lie, but this has also been associated with thinking behaviors. So if you have to try and come up with the answer to something, people will often look up and to the left as well.

MOLLY BLOOM: So a lot of our listeners may have seen a lie detector test in movies or TV shows. And those are in fact, a real test called a polygraph. It tries to detect if someone is lying by measuring changes in things like blood flow and breathing, or how much you sweat while being asked a series of questions.

But it turns out that they are not super reliable at detecting lies. So are there other lie detection methods that scientists are working on?

ANGELA EVANS: The field is looking at lots of different ways that we can, maybe, somehow figure out who's telling the truth and who's telling the lie. Some of the computer ways that the field is using to try and detect lies include things like thermal imaging.

And this is imaging where you can look at whether or not there's some kind of increase in blood flow, subdermally, when someone's telling a truth or a lie. They've also looked at brain fingerprinting. So they look at brainwave activity.

And this has actually been something that's really exciting because it's looking quite accurate at detecting whether or not someone is telling the truth or a lie. It seems to be much more accurate than the polygraph.

MOLLY BLOOM: It seems like your job would be a lot easier if people just told the truth more.

ANGELA EVANS: Yeah. So given that we're actually really bad at detecting lies, a lot of the research has started looking at ways that we can encourage people to tell the truth instead of trying to figure out when they're actually telling a lie.

And one of the simplest and easiest ways that we've found to encourage honesty is simply asking someone to promise to tell the truth.

MOLLY BLOOM: So just asking people to tell the truth helps them to tell the truth.

ANGELA EVANS: Yeah. And in particular, if you get them to verbalize that promise. So instead of saying, I want you to promise to tell the truth and they say, OK, saying I want you to say that I will promised to tell you the truth and get them to say, I promise I will tell the truth. And this promise acts as this verbal commitment.

And what we've found is that asking someone to promise to tell the truth before you ask them a question about something you want them to tell the truth about decreases lie telling by 30% or 40%.

ELENA: That's really interesting. Thank you, Angela.

ANGELA EVANS: Thanks so much for inviting me. It was fun talking with you today.

ELENA: We aren't born knowing how to lie. It's something we learn as our brains get smarter.

MOLLY BLOOM: To lie, you have to be able to imagine what someone else is thinking.

ELENA: We're social animals. And lying can, sometimes, make it easier to live and cooperate with other people. But lying too much or about fake things is not good for the social group we live in.

MOLLY BLOOM: Other primates also lie. But we're not sure they think about the same way we do. It

ELENA: Can be really hard to tell a lie from the truth. But telling the truth is usually the right thing to do.

MOLLY BLOOM: That's it for this journey to the land of lies.

ELENA: Brains On is produced by Mark Sanchez, Molly Bloom, and Sanden Totten.

MOLLY BLOOM: Menaka Wilhelm is our super talented fellow, and that is the honest truth. We had production help from Christina Lopez and engineering help from Michael Osborne. Special thanks to Josh Holt, Eric Wrangham, Shelly Langford, [? Coco ?] Sanchez, Vicky [INAUDIBLE], Peter Cox, Bill Catlin, and Iris Blandon-Gitlin.

ELENA: Before you go. We've got a real true answer to one of your questions. It's the Moment of Um.

SPEAKER: Um. Um. Um. Um. Um. Um. Um.

CATHY: Do We still get sponges from the sea? Or are they made out of something different?

JENNIFER QUINLAN: We do still get sponges from the sea. Most of the sponges that we have in our homes that might be to clean our bathroom or to clean our kitchens or to use outside, clean our house, those aren't from the sea. Those are now made from chemicals.

Hi. I'm Dr. Jennifer Quinlan, and I study food safety or how to make sure that people don't get sick from the food that they eat. Sponges from the sea are actually animals. They're not plants or corals. And they tend to absorb a lot more water. And they tend to be softer.

To make that sponge from the sea, they actually cut the top of the animal or a piece of the animal and dry it out, and then they actually bleach it to make it the type of sponge that we might see.

Sponges that aren't from the sea are made up of a number of different things because they all have slightly different textures. Some of them are squishier, and some of them are harder. But they're all made up of what are called polymers, which are plastics. So they're made up of different types of plastic.

So the sponges that we use in our kitchens can actually end up letting bacteria grow in them. They hold water. And if there's food caught in them, then you can get bacterial growth. So we have to be really careful with sponges that we use in our kitchen to make sure that we're cleaning them.

MOLLY BLOOM: And now a few big squishy high fives for these fine listeners. These are the kids who send in amazing mystery sounds questions and drawings. This is the latest group to join the Brain's honor roll.

[LISTING HONOR ROLL]

That's it for this episode of Brains On.

ELENA: Thanks for listening.

[KNOCK]

LIE: Come in.

GARY: Hey. Great job out there today, Lie.

LIE: Why, thank you, Gary.

GARY: And hey, I have something for you.

LIE: For me? How delightful. Oh, Gary. It's-- it's--

GARY: The pineapple zebra shirt. You liked my shirt so much earlier. I was able to find you a matching one. Twinzees.

LIE: Oh, Gary. You shouldn't have.