The Rest Is Science - The Reasoning Test Psychologists Still Can't Explain

Episode Date: April 20, 2026

Why do almost all of us struggle with a simple reasoning test, yet get it right the moment it’s about a pint in a pub? This week, Professor Hannah Fry and Michael Stevens take on the Wason Selection Task, one of the most intensely studied problems in the history of psychology. They unpack why a rule involving letters and numbers can feel strangely difficult, while the exact same logic becomes immediate and instinctive when it’s about people, rules, and catching someone out. From counterexamples and conditional statements to confirmation bias and the limits of human reasoning, they reveal why we rarely look for what proves us wrong. Along the way, they tackle a bigger question: did reasoning evolve to uncover truth, or simply to help us get along? ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit ⁠⁠https://cancerresearchuk.org/restisscience⁠⁠ Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Find The Rest Is Science all over the internet by ⁠⁠clicking here.⁠⁠ ------------------- Video Producer: Adam Thornton + Oli Oakley + Jack MeekAnimator: Sam BensonVideo & Social: Bex TyrrellAssistant Producer: Lucy LipscombeProducer: Simona RataSenior Producer: Lauren Armstrong-CarterHead Of Digital: Samuel OakleyExec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

Hey, hello, and welcome to The Rest is Science. I am Michael Stevens. And I'm Hannah Fry. And today, I really, really want to talk about a task, a test that basically everyone fails. I have a hunch that you won't fail this test, Hannah. Not so sure. We'll see. We'll see. Let me give you some context first, which I shouldn't normally do. because in actual experiments where this task is given, people are just there to get their $10 and go.

And I think that if you hype it up and you tell people, oh, you got to really think about it. Oh, it's so difficult. Oh, it's such a tricky one. Then people will probably spend more time and get it right. Okay? We could talk about all of that later, but let's just dive right into it.

This is a reasoning test, a very simple single question that involves four cards that was devised in 1966 by Peter Kemp. Cathcart-Wasson. And it is basically the test when it comes to studying the psychology of reason. All right. If you look into the history of our scientific study of human reasoning, you basically only find this test. The test is called the Wasson selection task, and it was developed in 1966 by Peter Cathcart-Wasson. Now, today it has been called the most intensely researched single problem in the history of reasoning. And my two favorite philosophers, researchers of reason, Mercier and Sperber, they call it what

actually they don't know what to call it. This is what they say. Is this selection task to psychology of reasoning what the microscope has been to biology? or is it rather as the Rubik's Cube has been to biology? Just kind of baffling and fun. Not adding anything really of any merit. So in Wasson's original test, only 10% of people got it right. If you look across all the studies that have replicated that sense,

you get a number closer to 4%. And that's not super-success. surprising. There are difficult questions out there, but with some slight changes, we can make everyone get it right. And that is what is so strange. So let's begin with the original. This episode is brought to you by Cancer Research UK. Here's something strange. Your DNA contains more ancient viral fragments than genes. The genes that build our cells make up only 2% of our And for years, that is what scientists focused on. They treated the rest, the ancient viruses and stuff, as junk.

But now we know that that hidden majority, sometimes called the dark genome, influences how our biology works and how disease like cancer behave. It's a reminder that progress rarely comes as a single breakthrough. It builds gradually. Cancer Research UK plays a central role in that progress, supporting decades of research into over 200 types of cancer, work that's helped double survival in the UK over the past 50 years. For more information about Cancer Research UK, their research breakthroughs, and how you can support them, visit cancerresearchuk.org forward slash the rest is science.

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I want to help my kids, and I want to give back to the community. Ooh, then it's the vacation of a lifetime. I wonder if my out of office has a forever setting. An IG Private Wealth Advisor creates the clarity you need with plans that harmonize your business, your family, and your dreams. Get financial advice that puts you at the center. Find your advisor at IGPrivatewealth.com. This isn't the most, I'd say the most famous version of it, but this is exactly what Wasson gave people back in 1966. Those of you who are watching, we can put up on the screen the actual original puzzle as it was shown to people.

For those of you listening, no big deal. This is an easy one to do with audio. You just kind of have to keep four things in your mind. I'm going to show you four cards. Just imagine they're like playing cards. Now, on each, there is a letter on one side and a number on the other side. Two of the cards have their letter side up,

and two have their number side up. Now, these are the cards that you see. You see a card with the letter A as an alpha, G as in giraffe. That famous phonetic dictionary, yeah. Oh, it's going to get worse, Hannah. The third card has a 7 as in 724. And the last card has an 8 as in 81.

A.G.7.8. Okay, now, what I need you to do is indicate for me which of these cards you would need to turn over to judge whether the following rule is true. If there is an A on one side, there is a seven on the other. To recap, for those who are listening, you have four cards in front of you, letters on one side, numbers on the other. Okay? That's true. But you can only see one side of a card at a time. And what you're seeing is A, G, 7, 8. Which ones will you need to turn over to judge whether this rule is true? If there's an A on one

side, there is a seven on the other side. Okay. That is what this episode is about. I mean, I think let's just get into it. Let's get into it. So, so, take some time. Also, actually, I want to know how familiar you are with this, Hannah. Have you seen this before?

Okay. I have seen a version of this test before. And what I should tell you is that initially I think I got it wrong. Yeah, me too. I also vaguely remember the trap that I fell into, but not completely. And I haven't seen this version. And so I'm going to have to think it through incredibly carefully. Okay, think it through.

Okay, so right, you know that these four cards, a letter on one side, a number on the other. Sure. Okay, which means that there is a number hiding behind the A, there's a number hiding behind the G. That's right. There's also a letter behind the seven and there's a letter behind the eight. the rule says if there is, this is what I'm trying to test, if there is an A on one side,

there is a seven on the other. Right. So turning over the eight doesn't tell me anything. I mean, I don't really care what's on the other side of the eight because even if it's an A, oh, no way, that's not true. Mm-hmm.

Oh, hold on, I've got it wrong already. Yeah. What I was immediately thinking was, I want to turn over the, A to see if there's a seven on the other side, right? Okay. Immediately, the first thing you want to do is check whether there's a seven on the on the reverse of the A.

Okay. All right. So you're going to turn over the A card. Any others? To see if there's a seven. Turning over the G, I don't think tells me anything because I don't really care what's on the reverse of the G. The rule doesn't involve G's.

Okay. It says if there is an A on one side, which there isn't, so I don't care. So I can ignore the G card. The seven card, I'd be really tempted to turn over to see if there was an A on the other side because then that would be another instance of the rule. Right. But the way the rule is phrased is that it says if there is an A on one side, there is a seven on the other. It doesn't say you can only have sevens where A's exist.

Correct. So actually, you could have a J on the other side of the seven and it wouldn't violate the rule. That'd be fine. That would be fine. So even though my temptation is to say turn over A and 7, actually, I think you need to turn over A in 8. Because if you turn over 8 and it's got an A on the other side, that would violate the rule, right? Correct. You feast it, Hannah. I mean, I did, but I almost mucked up at the beginning there. Let's be honest. Well, it's amazingly tough like that. Now, imagine that you weren't a professor of mathematics at Cambridge on a podcast. called the puzzle almost everyone gets wrong.

Yeah. Yeah. And having seen it before. And having seen it before. Yeah. Wow. You're right. So I want to immediately jump to a different version.

This is the exact same problem, except this time, instead of letters and numbers, the cards are about people in a bar or a pub for those of you across the Atlantic. Thank you. You're welcome. I'm sure you all were going, oh, what's he talking about? A bar? A bar. All right, look, the deal is that in this case, the cards are about people in a bar.

And on one side of the card, you have the person's age. And on the other side, you have what it is they are currently drinking. Okay. Once again, you have four cards, and you are a police officer, and it's your job to make sure that no one is drinking under age. On some of these cards, you can only see their age. You're going to have to turn them over to see what they're drinking. On others, you only see what they're drinking.

You'll have to turn them over to get their age. This is what you see in front of you, these four cards. The age 12, the age 35, the drink soda and the drink beer. Okay. Which ones do you need to turn over to determine whether or not the rule is being obeyed that you cannot drink underage? Okay, well, now is immediately. obvious to me that the person who is 30, they can drink whatever they like.

I don't care what they're drinking. And likewise, the person who's drinking soda, I mean, someone should speak to their parents about them being in a bar, but I don't care what they're, I don't care what their age is. It's not relevant. Yeah.

So immediately, it's like, well, what's the 12 year of drinking and who's drinking the beer? That's it. Right? I mean, that's it. It's the exact same answer as the one before, the first and the last card. except it's just so much faster to get to the answer.

Yeah. Like the original formulation of that is genuinely confusing, extremely difficult to logically work your way through. And even when you get there, you're, I don't know, I'm really like double checking myself. But that other one is instinctive. It's automatic. Yeah, no one needs an explanation for why you need to check the 12-year-old and the beer drinker.

It's almost just evident prima facie. Like, I get it. Whereas when we replace the ages and the beverage with numbers and letters, it becomes very abstract. And, of course, we see this reflect in people's performance. When it comes to letters and numbers, like I said, four, maybe 10% of people get it right. But when it comes to the beer and the ages, everyone gets it right. I mean, the people who get it wrong are the people who are like just trying to be goofoffs. Seriously, it's like, it's like this not, it's not even really a question.

So why is it so much more difficult for us to solve the problem when it's abstract like this? Is that the key to explaining why this is so difficult? Well, as you can imagine, for the last, you know, gosh, 50, 60 years, 60 years now, actually, this year. Happy birthday, Watson's selection task. You are old enough to drink. Congratulations. You're old enough to drink for sure. You're not quite old enough to collect Social Security in America, though.

But when that day comes, we will be here for you. Researchers have spent decades creating slightly different versions, including the drinking in a bar version. The question is, is this revealing something about an individual's abilities, or is it revealing something even deeper just about humans in general because it doesn't necessarily seem to separate the smarty-pants people from the dum-dums. Even really smart people tend to perform about as badly. You can take, you know, a big Harvard graduating class and they'll struggle with it too.

The things that we know help people solve it is making the puzzle be about a social rule or phrasing the question in a way that makes it extremely clear that they need to be looking for today's magic word counter examples. Right, so can I ask some questions? You can. The 4% of people who do get it right, who are they then? In the original formulation of the test or some variant of? I haven't actually found a lot of good breakdowns on who those people are.

Like literally in the literature, they're often called exceptional people. I'm serious. I'll show you the papers. They're like, if you get it right, you're either an exceptional person or a lucky guesser. There was one paper that said like the best, the most strong correlation is whether you have taken logic classes. Okay. So it's sort of mathematically minded people. Exactly.

It's people who go, aha, yes, I am familiar. with modus tollens and denying the antecedent, and here we go. Do you want to give us a quick rundown on modus tollens? Oh, yeah, for sure. Okay, so, I mean, look, the Wasson selection task presents us with what's called a conditional statement. If then. We use these all the time. Hey, if you don't call me back, then I'm going to punch you in the nose, right?

If then, all right? Now, logicians, people who study the rules of reasoning, people who study logic, they have all kinds of fancy terminology and symbols for the parts of a conditional statement. The if part is called the antecedent. It comes before the end, which is called the consequent. An example would be, if it rains tomorrow, I will stay indoors. If it rains tomorrow is the antecedent. I will stay inside is the consequent. So if this thing happens, the consequence will be this.

If it rains tomorrow, I will stay indoors. Okay, so if you can take that single state, that single sentence, if it rains tomorrow, I'll stay indoors, and sort of chop it into. And then it's almost like there's two logical chunks there, right? Raining tomorrow, which it can or it can be or not. It's either raining or it's not. And then you've also got you staying inside, which you could be or you could not be. That's right.

could sort of imagine like a little grid, right? So it's like whether it's raining or not is on one side and whether you're staying in or not is on the other side and you can kind of go through and go true false, true false, true force, true force, right, for the different combinations. Not six times though, just four. Sorry. Which is extremely important though. I'm glad. I went back around to the beginning. You were so excited. Yeah. You're living on that Pac-Man universe again. You went around. But yeah, there's only four combinations here and how many cards are there in the Wassen selection task? There's four. Now, we don't need to make this like

a full-on, let's get into the weeds with logic thing, but let's do it anyway because our viewers are special. And I'll give you another little... They're that four percent. They're the exceptional people. They're the four percent. So the antecedent, I think maybe we could also just call it P. If you read a lot of logic papers, which I think we should. I'll send these to the producers. We should put the best papers about this down in the description. P, the letter P is often used to represent the antecedent. The first bit, the if bit. The if bit.

If P, and you use a variable because now it can mean anything. If it rains tomorrow or P could also mean I eat a ham sandwich. If P, if I eat a ham sandwich, then what? I will smile. Okay. The consequent is often symbolized with the letter Q. So now we can start talking about the conditional statements like their math equations. if P then Q, if P then not Q, blah, blah, blah, blah, blah.

And we can talk about all the different ways we can work with this statement. So there are two valid ways you can use that statement to what draw a conclusion. Could you, though, these cards, could you think of these cards then, to give your example of, if it rains tomorrow, Michael will stay indoors? Instead of this being AG7-8, could it be Michael's indoors, Michael's outdoors, it's raining, it's not raining? Exactly. That is exactly what each of the cards in this selection task do. They've got P, not P, Q, not Q. And so in order to answer this correctly, you need to show that you understand or have an innate ability to use a conditional statement in the two valid ways that an argument can be formed. And that's where we get to modus tollens and modus ponens. I'm probably not pronouncing those right. But look, this is about logic, not pronunciation. So modus ponens is the really easy one where we say, here's a rule. If it rains tomorrow, Michael will stay indoors.

It is now tomorrow and it is raining. Where is Michael? And they go, well, he's indoors. I can conclude that. Yes, that's valid. The other example would be your overage and your drinking an alcoholic drink, right? That would be the other. It's true.

It's true. It depends what the rule is about drinking. Okay, the rule is everyone over 21. So everyone drinking must be over 21. I think so, yeah. If you're drinking, you must be over 21. Right. Or 18 or whatever.

I didn't give a year, I just said. You did. You smartly did that. I smartly chose 12 and 35 so that. Look at that. I've anchored us to the wrong side of the Atlantic. I know. Look at that.

And I did all the work to use the word pub. I know. I really should have repaid you better. I apologize. Nice. Okay, so the modus poland then is if you're drinking, you're over 21, so it's the person with the beer, say, who turns out to be the correct age. Yeah. Yeah. You know what? I think the sentence would be, if a person is drinking alcohol, they must be over, like 21 or over. Yeah. Therefore, modus ponens would be, hey, they're drinking alcohol. Therefore, they must be over 21. I understand. Yeah. So, so modus ponens is about affirming the. You know, antecedent. We know that the first, the if part is true, therefore we conclude the consequent, the Q part. Now, it is invalid. It is invalid to have the antecedent denied and then conclude something about the consequent. Okay, you're going to have to do that one again for me.

Okay. Modesponin's is when you affirm the antecedent. You say, hey, the if part is true. Therefore, the then part must be true. If, however, you are able to deny. the antecedent. For example, in our raining example, you say, well, hey, it's not raining. You cannot conclude that I'm not indoors, because the rule doesn't say anything about other reasons I might stay indoors tomorrow. Now let's talk about the consequent. A valid way to operate with what you know about the state of the consequent is that if it's denied, in our original case, Michael is not indoors, then you can conclude that it's not raining. All right. Let's do this with the drinking example, because this is the one that I, like, strangely, I find

most, I can understand most instinctively. Okay. So to make it, to make it really easy, let's say that in this bar, it is true. The law is being followed. Everyone who's drinking beer is over 21. If you're drinking alcohol, you are over 21. And that's true. If you're drinking alcohol, you are over the drinking age. So if you get someone who is not over the drinking age, then you can conclude that they can't be drinking alcohol. Correct. That is modus tollens. Right. However, if you affirm the consequent, you cannot conclude anything validly.

Meaning, if you run into a person there at the bar and they are over the drinking age, then you have no idea what they're drinking. It doesn't mean anything. You cannot conclude that they are drinking alcohol because they might not be. Got you. And that, so then, so then what's that? That's not modus tolerance or modus. No, that's called affirming the consequent and it is invalid. Okay. Now, if all of this sounds really confusing or boring, just rewind, listen again, over and over again.

We can get some really cool boosts for the algorithm. Just remember that you are here to learn not to be entertained, okay? That's right. That's right. I'm not going to just do a dance for you. I'm going to sit here and mispronounce Latin words for an hour. This is a very special episode of the podcast where at the end we give you a test. And if you are in the 96% who failed, you'll not allow to listen again. Oh, my goodness. I didn't know that rule.

Speaking of conditional statements, if you don't understand, then you will not listen again. The point of all of this is to say that the difficulty of the Wasson selection task is that the human brain must just not have an innate modus tolin's ability. Like, we have since our evolution into modern humans developed and discovered all this stuff about logic, but we just aren't born with a logical table in our brain. But that can't be true because the bar example is so instinctive. It's so instinctive. Yeah.

The words that we're using here and the language that we're using to describe this, I mean, it does sound super duper complicated. It sounds extremely mind-boggling, even if the original sentence is quite simple. But then as soon as you put it in the bar example, it's like, well, I don't even have to think about it. I know. That is so strange. That is weird. And it's got to be significant, right? So in the late 80s, two researchers, Lita Cosmides and John Tooby famously said, guys, this whole task and the fact that the social ones are so much easier is clearly evidence that our reasoning ability evolved for social reasons, not for truth-finding reasons.

So when it comes to creating different versions of the Wasson selection task, the versions that involve really abstract stuff and facts are called descriptive. Okay? It's just the way it is. If there's an A on one side, there's a seven on the other. Now, if it instead involves a rule, an obligation, a duty, something that humans made up, it's called Deontic. Okay? I love these words because they're both called rules or laws, and yet one is about can and the other is about May.

I don't travel at the speed of light, not because I'm not allowed to, but because I can't. Okay? And so that kind of a restriction is called a descriptive restriction. But when it comes to are people breaking the rule? We need to make sure people are complying with the rules. That's called a Deontic rule. Where did that word come from? I don't know.

I mean, Deontic etymology. Because what other words use it? It means being needed or necessary from ancient Greek pertaining to necessity, duty, your obligation. So Cosmides and Tobe famously are like, guys, this is just human nature. We evolved to focus on duties and obligations that we invented ourselves and not on universal, timeless laws of impossibility. We care more about may I do this than can I do this. I also sort of wonder a little bit about that point about truth finding. Because the example of people in a bar, It's partly about social rules and social norms, but isn't it also a little bit about truth finding?

Isn't it also a little bit about who should you be suspicious of? Yes. Yes, it is. But it's just it's a truth that is human focused. It's a truth in the domain of deontic principles, obligations, duties and rules and obedience, as opposed to one of an abstract wall. If it has an A, it must have a seven. Yeah, of course.

Here's the typical responses people give to the selection task. 46% of people pick A and seven. Okay. Okay. So almost half of people do that. A third, 33% choose just A. Right. 7% of people choose A, 7, and 8.

So almost everybody is picking A. Yes. And then only 4% of people choose the correct cards, A and 8. The other 10% of people choose other combinations. Some people choose all of them. I mean, at that point, I think it's kind of believed that they just either didn't understand or didn't. care. Or just want to finish. They're either the anarchist or they're like, get me out of theorists. Or maybe they understand something we don't. I mean, I'm not going to dismiss them.

Maybe they're the ones with modulus tolerance in their own heads. Yeah. The thing that makes me feel a tiny bit uncomfortable about this, this idea that humors are not innately good at truth finding, even though I'm sure that these researchers have thought about this much more extensively than I ever have, is that science really is based on the hunt for truth. And okay, admittedly, We have come up with really strict methods like hypothesis testing in order to do that. But does that sort of mean that, I don't know, science isn't innate? I'm not sure. That's a really good question.

And I'm starting to feel like it's not that innate that we, from tests like this, we found that we are focused more on our own social lives and ourselves and not on what is the best way to test a hypothesis. Now, the Wassen selection task makes it pretty clear that we're bad at finding counter examples or even being motivated to find them. Like pretty much everyone chooses the first card A. They're like, I need to see if this is an example of a thing that follows the rule. But very few people go, but I should also look for a case where the rule is not true. Is broken. Even though you find a counter example, you're done.

If the rule is that if there's an A, there's a seven on the back and you can find an A that doesn't have a seven on the back, you're done. You can walk away and say the rule's not true. I've proved it wrong. Now, there's a great study. I was actually cracking up last night reading about this. I don't think it's going to seem that funny today when I tell it. But there was a study that was done by Johnson, Laird and Watson in 1970, where they had two boxes of shapes. In one box, all the shapes were painted black, and in the other box they were all painted white.

And they told people that people couldn't look in the boxes, okay? The researcher sat there with these two masked boxes and was like, okay, here's this rule. And I want you to test whether it's true, whether this hypothesis is true. All the triangles are white. Now, tell me what to do and I'll do it for you. And people would say, oh, the first thing almost everyone says is, okay, I'd like to see a white shape. So he reaches in there and he pulls out a shape and it's a white triangle, low and hold, because literally the only thing in the white bin are white triangles.

He pulls it out. And people tend to just keep asking for white shapes over and over again, all right? And they keep getting a white triangle and they're like, I don't know, I was feeling like it's pretty proven. And then after a while, they start to go, maybe I should see a black one. Because they start to realize, oh, shoot, all it takes is one black triangle to blow the whole thing to smithereens. But basically no one starts with the black shapes. That is so fascinating. That is so fascinating.

I think you've seen this in science as well, right? I just wrote this, I wrote actually this chapter of the book that I'm doing at the moment. I wrote this whole thing about Popper, about Carl Popper and about how he said that the key point about science. is essentially trying to find things that break your own theorem. You should be hunting for the counter examples, not for the evidence that supports it. There's a, the thing is, is that it's like, it was really, really hard for people to do this.

It's not instinctive at all. For almost all of scientific history, people were just like, let's gather more evidence, let's gather more evidence. And actually Einstein, you know, one of the reasons why Einstein is considered so phenomenal, is that when he came up with his theory of general relativity, as part of his theory, he said,

here is the way you can prove me wrong. This is my idea. This is what I think it is. There's going to be a solar eclipse in a couple of years. And if I am right, the light will bend around the sun in this way. You'll be able to see the stars that are normally blinded by the sun's glare. Off you go, here is how to find the counter example. And that was a really bold, brave, unusual, crazy thing for him to do.

It's the same as your black shapes, right? People do not go hunting for the black shapes. But Einstein was someone who knew that you had to. He did. And I think, back to your original question, I think that that meant he was a little bit less human than most of us. He was willing to look for counter examples and was not just looking for confirmation of the one kind of thing he believed in

and wanted to find more of and finding more of them would make him feel more and more confident he was willing to say, guys, we got to find a counter example. We've got to find something that shows that I'm wrong. Here's one way we could do it. Here's another way.

The creator of the Wasson selection task became obsessed with our terrible, terrible laziness when it came to finding counter examples. Okay, well, look, we need to take a break, but when we come back, Hannah, I want to show you an even earlier game that Wasson came up with that brings us to, I think, the same surprising conclusion about humanity. Imagine if he was your dad.

He'd constantly be tricking you, wouldn't he? I know, but like dads are always tricky, but this dad is tricking you. This is the trickiest tricks. For science. I got your nose. Why do you think I got your nose? Have you not developed body permanence yet? Dad, leave me alone.

Yeah. Yeah. Hey, what's that on your shirt? Oh, gotcha. What's wrong with your perceptual apparatus? Let's try that again. And you're like, Dad, just prank me to embarrass me, not to learn. All right, but we're going to do some of that after the break. Great. This episode is brought to you by Cancer Research UK. We often think of beating cancer as treatment, but imagine stopping it before it begins. After years of work, cancer research UK scientists are launching a clinical trial of lung vacs, the first vaccine designed to prevent lung cancer. It builds on TracerX, the world's largest cancer evolution study, which tracked lung cancer cells over many years to uncover the disease's earliest warning signs. Lung Vax is designed to train the immune system to spot these signs early on, destroying 40 cells before cancer develops. So it's not treatment, but preventative, with the potential to stop lung cancer before it starts.

The first stage of the trial starts this year focusing on people at higher risk. It shows what long-term research makes possible. For more information about Cancer Research UK, their research breakthroughs and how you can support them, visit cancerresearchukuk.org forward slash the rest is science. Amazon presents Jeff versus Taco Truck Salsa, whether it's Verde, Roja, or the orange one. For Jeff, trying any salsa is like playing Russian roulette with a flame thrower. Luckily, Jeff saved with Amazon and stocked up on antacids, ginger tea, and milk. Habaniero? More like Habinier, yes. Save the everyday with Amazon.

This episode is brought to you by Defender. With its 626 horsepower twin-turbo V8 engine, the Defender Octa is taking on the Dakar rally. the ultimate off-road challenge. Learn more at landrover.ca. Welcome back. All right. So Hannah, here we go. I'm going to give you some numbers. Again, because of who you are, Hannah, you might do really well at this. That puts more pressure on me. Go on. Good, good. I want this to be uncomfortable. Look, what I'm going to do is I'm going to name triples of numbers. I'm going to name three numbers that fit my rule. It's a secret rule I have up here. And then I'm going to just give you one. example and then I want you to start naming triples and I will tell you yes or no whether it fits the rule. Eventually, I want you to be able to tell me what you think the rule is. Okay, cool. Okay. So here is a triple that fits my rule. Two, four, six. Okay. All right. Now, I want you to start producing triples and I will tell you if they fit the rule or not until you can guess the rule. All right. Six, eight, ten. Correct. That fits. Okay. Seven, eight, ten. Seven, eight, ten.

That fits. 666.6. Nope. 6.7.8? Yes. I think I've got it. What do you think it is? Hang on. Let me try one.

Okay. 765. No. It doesn't fit. 786. No. Is it just going up? It's just going up.

Hannah, you're brilliant. that's the first time this game was played on me. I'm still playing that game, by the way. I just walked away. And it wasn't until last night when I read about the history of Watson that I was like, oh, that's it. The answers that they just have to go up. No.

To be fair, though, you primed me because you said fine counter examples. I did. You primed me. Well, how about this? Editors, edit this around so it looks like that's the very first thing we did. The point is, all right, yeah, I'm still a bit impressed. you did a good job of at least making it look like you didn't know exactly what to do. The counter examples you asked for is what unlocks the whole thing.

Of course. They give you, there's so much more information contained within a counter example than there is in something that confirms it. That's right. Whereas if you play this, if you're listening, please go try this with your friends and family today. They will thank you. It's so fun. But you'll find that what they tend to do is that people tend to think of what the rule might be and then they think of other things that might fit that rule and they ask them. again and again and again.

And they rarely go, I think the rule is this. So let me think of something that wouldn't fit that rule and test it. Now, why don't we do this so much? Obviously, we don't know, right? This is, it's all very speculative. But I think that Comedes is really on to something with this idea that reasoning didn't evolve to help us solve mathematical puzzles. It originally evolved to help us work together and explain ourselves to each other because humans are just too weak. We need each other.

We need to cooperate. And that's the only way we're going to be able to build and collect and hunt. So we have to be able to communicate what's going on in our heads. We don't have to do it well. We just have to make sure that people trust us and feel like we're playing the game. Okay. So on that topic, I would highly recommend Hugo Mercier and Dan Sperber, the Enigma of Reason. This goes really deep into their social theory of reasoning, which is that, look, we don't use reasons to come to conclusions.

We use conclusions to come to reasons. We just intuitively feel and want to do things. And then when we're asked to defend it, we confabulate in our own heads all the reasons we had for it. And we believe them. I think what I'm like is calling to mind about this is that actually when there are situations where people do see counter examples where which puncture their theories, it's not like we innately very happily get on board and just like go along with it. You know, we look for reasons why the counter example doesn't exist. I mean, I'm thinking here about, I don't know, biology and this sort of sense. 17, 1800s where they, they spent absolutely years like merrily shooting things and pinning

butterflies to boards and putting birds in sacks and stuff and deciding that, you know, birds are one branch of the tree of life and mammals are another. And they had it all perfectly neatly categorized these rules. And then someone comes along with the platypus body and they have no idea what to do. And rather than saying, oh, okay, hang on actually, this is a really, clear counter example of the ways in which I rule is wrong, they cut it up looking for stitches, they thought it was a fake, you know, they spent, they spent nearly a hundred years being like, well, this is just can't, can't be possible rather than, rather than, are you saying the platypuses are real?

I thought they were Frankenstein together by some pranksters like jackalope. I mean, that's what they thought too. I've never seen one in the wild of you. So, I've never seen one in the wild. Basically, I'm taking someone's word for it. So, you know, no, that's, that's exactly it. Um, And when a whole group of people refuse to accept counter examples, that's when things can get pretty dangerous. Because the conclusion that I think all of this is pointing at, and this is my opinion, is that we truly reason. That is, we give reasons for things and we extract knowledge from knowledge we already have, which is what reasoning is, to get along and be social. And I think that if you really meditate on the consequences of that, suddenly a lot of stuff makes sense, like confirmation bias, which is what we've been talking about this whole time.

Absolutely. The pursuit of finding things that prove your hypothesis correct and ignoring or avoiding a search for things that might prove it wrong. Confirmation bias, I think, works really well when you consider the fact that we're supposed to all be working together. As a group activity, it actually saves time if each of us goes off and finds evidence for our own pet theory, and then we come and combine them. If instead we didn't do that, if we didn't have a confirmation bias, and we all went off and we did all the research and found everything and read all these different counts, there'd be too much work for all of us to do. Let's each split the task up, many hands make light work, all go and find evidence for what I believe.

You find evidence for what you believe, and then we'll come together. And you've already done a bunch of work on topic A, I did topic B, and we combine them. That seems to explain confirmation bias and so many of our other biases so well. I also love that it kind of pushes us to this conclusion that humans need to work together. We need to listen to people even if we really do not agree with them. I'm also thinking here about, I don't know, I have like a few years ago I was doing quite a lot of work on vaccine skepticism. Oh yeah. And working with people who were hesitant about the COVID vaccine.

Now, I have to be a tiny bit careful about what I say about this, because what I will say is they are a vocal community. They are not afraid to tell me what they think. Yeah. I'm just going to tread delicately and carefully. I also made lots of mistakes in the way that the whole thing was approached. But the thing that I noticed is, well, twofold. actually. One is that people, the only way that people make decisions is in an emotional way. It may be

that you and I, who are scientifically minded, believe that we make decisions based on statistics, but ultimately for us, that is still an emotional story. We have an emotional relationship to data and mathematics and science in a whole story of our lives that kind of builds up to that moment. and it's still an emotional decision. It's just a slightly different one. I think people are not persuaded by data and numbers. I think it is always fundamentally about the social aspect exactly as you describe, right? Because if it was about data, then you could show somebody the right piece of data.

You could show somebody the right combination of words and it would change their mind. And people do not work like that. That's not how it works at all. And the second thing that's called to mind here in what you're describing is there's something, thing which is called the deficit model of public communication. Ah, I haven't heard about this. Okay, so when you work in an academic institution, there's a lot of talk about how do you get your, how do you get the scientific ideas out to the public, right?

How do you talk to people about this? Especially when you look at situations where people are making choices that are maybe counter to their health or maybe counters to public health more generally. How do we get the information out there so that people make better choices, make choices that align more carefully with what's right for them and what's what's right, you know, overall? And for a long time, people thought that all you needed to do was just give them information, you know, that if you educated people to the correct level, that if you put information out there, then that would be enough. But the problem with that idea is that it's called the deficit model because it's essentially saying that the only problem is that the public have a deficit of knowledge, right? They just need the facts. They just need the facts.

And it is the most arrogant, insulting way to, I think, belittle people. And basically imagine that the only reason why somebody is not making the same decisions as you are is nothing to do with their ones. worldviews, nothing to do with their own, their own version of reasoning, the things that are important to them, it's just because they don't know as much as you do, right? Right. And not only is it incredibly insulting, it also demonstratively does not work. You cannot argue or maths your way into changing people's minds or persuading them. It just doesn't work.

And I think that the way that you've described all of this stuff, the way that people, people's logical brains are not geared for statistics and data and abstract descriptions and the way that our brains are geared towards the social aspect of aligning with other people and collaborating. I mean, just looking at the sort of anti-vax movement against that perspective, it just really, really, really resonates with me. Yeah. You know, it's kind of frustrating, but it's almost a relief to realize, oh, my gosh, you're

right. It's not that with the right facts and reasons we'll all agree on something, because that's not what happens. My favorite demonstration of this was something we did on Mindfield, where we had a magician come in and act like he was doing a study on appearance. And he showed people two photographs at a time and said, which of these two people would you rather work with in an office? and he would put the people that were chosen in one stack and the people that were not chosen in another stack and he did this over and over again. And then he said, okay, now I want to go through everyone

that you chose to work with and I want you to tell me why you picked them. But he was a magician. So he used sleight of hand to actually slip in a bunch of the people that they had dismissed as I don't want to work with a person who looks like that. And he would then show them the cards and they gave reasons. And whenever, every time, without exception,

he would show a face that the person had rejected, they'd go, oh yeah. So I picked this person because I really liked the way their eyes kind of looked like. They might have like good inside jokes. The point is that we use reasons to explain ourselves and express who we are at a deep level. We don't use them because of anything logical and timelessly true. It was so awkward to watch people defend and explain why they chose a person that did not choose. It was embarrassing for them, but yet it was It was enlightening for our species. Yeah.

And we're just a mess, Michael. We're all just a big sloshy mess with our squirty water computers. That is true. And the only way to rise above that is for us to stay a big sloshing mess because the average of all of us winds up being better than one individual's opinion on their own. Yeah. I mean, this is the wisdom of the crowd stuff. Right. That's right.

And this is something that's really important to me. I really believe in it. I did an episode about Latocracy and how I would really love a government run by random people. Like, rather than electing people, let's literally just be like, look, there's a lottery every four years. And you'll just get asked to come and be a member of Congress or parliament or whatever, the House of Lords randomly. You'll do your term. You'll get paid. There's housing for you.

And I think that it would be amazing what would happen if you like took such a variety of views and had them all kind of average each other out as opposed to what we have now, which is like, hey, we're all kind of in this political class. Let's be leaders. We all kind of already feel the same way. Great, great, great, great, great. Yeah, there's a superiority that comes with that. I think I remember reading something about this in Rory Stewart's book. Roy Stewart, of course, of Rester's politics fame, the lesser known. Go hang a podcast.

But he is extremely keen on the idea of town halls, but also of civilian panels, civilian assemblies. Deliberation days. Yeah, deliberation. Exactly. Why not? I mean, this is what we do in the judicial system. I mean, it's not perfect by any stretch of the imagination,

but I also think that it's the best that we've got. And it does exactly what you're describing. It stops pretending. that reason is some mathematically pure thing that we can march towards and instead accepts the messiness of human nature and that we are social creatures and social beings and we are totally perfectly tuned through an astonishing evolution to really prioritize that.

Right. Yeah, we evolved to be a group and work together. And so collectively, like all voting together, I just, it's hard for me to find a solution that's better than that. That's, it's better than asking any particular person or type of people to make all the decisions. We've got to all come in. And there are people who are, have terrible ideas. And sometimes people have terrible ideas that are opposite to each other and they cancel

each other out. And that's like our only hope is the hope that things cancel out. And what we're left with is the wisest way to go. What is your, what does your t-shirt say to say? Michael, I sort of feel like somehow, rather we've been... Oh, it's very reflective of kind of the mood that we've created here. Everything is terrible. With an atomic bomb going off in the background.

It's not actually the scent. I'm not saying that I feel everything is terrible. This is a troop of performers who collect found media footage and they do shows where they show it off. And they call themselves, everything is terrible. They're kind of like, they really love. love this like terrible forgotten media. They're a great group.

I don't actually, I haven't checked in on them in a while, but basically what we solved human nature today. Is that right? I think we probably did. We cracked it. We finally cracked it. When it comes to things that we do that are social, there's, there's another really funny example that I've been wanting to do a longer video about.

And it's the classic situation where you are at a restaurant and the waiter brings your food out and says, all right, enjoy your meal, and you go, oh, you too. I mean, thank you. Or, you know, you're dropping off your bag at the airport and the gate attendant says, all right, have her a nice flight. And you go, you too. Oh, shoot, no, I mean, thanks. Why do we do that? Well, there's a name for those kinds of exchanges, those kinds of words we say to each other. Back in the 30s, a researcher named Bronislaw Malinowski called these kinds of exchanges. is fatic communion. Okay.

Like you're breaking the bread together. That's right. It's communion. It's breaking bread together. It's showing that I'm here. I acknowledge you. We're both humans. But it's communion done through fatic means,

which means pertaining to language. So when we say things to each other, like, oh, hey, how's it going? I'm not literally asking, tell me how things are going. In fact, a common response to, hey, what's up? Or hey, how's it going? Is, oh, hey, man. You're literally not answering at all. You're literally ignoring their question. An alien would find that really weird. But we understand that I wasn't actually asking you,

what is up? Or how's it going? I'm just saying, I acknowledge that you're here. We're two social beings who can communicate. And we just need to say hi to each other. We just need to give each other a bit of a nod. That's it. A little bit of communion. A little bit of communion. And that's what the waiter does when they say, hey, have a great meal. You are, you're, you're, are you automatically ready to exchange these things without conscious thought? And that's why we absentmindedly respond with you to. I have heard from an American who moved to London. He found it extremely confusing when he first got here and people were like,

you're right, you're all right? He was like, what do you mean? Am I all right? Am I all right? I wasn't me that told you that? Because this was one of my biggest struggles when I first moved to the UK. Every time I entered a room, people would be like, You're right?

And I'd be like, what's wrong? Why do you think something's wrong with me? Am I acting weird? Maybe it was you. All right. But for them, just phatic communion was fatic. It was just a like, beep, beep, I am human too, acknowledged, right?

That's all they meant by it. Absolutely. And you see this between generations because what is and is not fatic changes over time. And so for like younger people saying things like, oh, no problem, is very fatic. If someone says, hey, thanks, and I'll just say, no problem. But to people in an older generation, they don't realize that it's fatic. They take it literally. They listen to those words, and they go, no problem.

Well, I didn't say it was a problem. Why would it be a problem? Do you think I'm acting like this was a problem? And so I thoroughly believe that by the time I'm an old man, I'll be at the grocery store, they'll bag up my groceries, all say, hey, thanks a lot. And they'll go, well, don't freak out about it. And I'll be like, I wasn't. I'm sorry. Why can't you just say no problem? And they'll be like, well, no, dude, I didn't,

I didn't say you were freaking out. I just said, don't freak out and you didn't. So, right? There is one. There is one, okay, that young Londoners say to each other. What do they do? They go, say less. Say less. Yes. Yes. It's like, by, I can't take my words back. The first couple of time I heard it. I was like, I don't think I was saying a lot, actually. I know. That's a great example of how fatic things are changed. I wonder what they were in really old times, though. I wonder what the fact at communication of sort of 1865 was. Just a bunch of belching? I don't know. Why did I just say something derogatory of 1860s people? They didn't deserve it. We know that they were belching all over their place.

They were just like, yo, hey, did you find anything? I did. I did. I've got a couple. Okay, tell me. I hope I see you well. I hope I see you well. Yeah. What say you on such day as this? Hmm. On a day such as this, sorry. How does all at home? That one, that one I wouldn't be too tripped up by. I'd be like, oh, it's fine. I hope I see well. But how would you respond? Did they say fine? Actually, how do you do? How do you do? I feel like I've, you know, sort of feel like the memory of that one has lingered.

Yes, yes. I would not be confused. If someone said, how do you do, I wouldn't go, how do I do what? The 1600s is the exact century. when the passing blessing, God be with yee, was said so rapidly and often as a phatic communion that it permanently mashed together into God be ye and eventually goodbye. Goodbye. You said the 1600s. Apparently. Wow.

Hello. Goodbye. Speaking of reasons. I think it's pretty interesting as I was fleshing out what I wanted to talk about today. I was like, wow, there's kind of three types of things we've talked about. We've talked about difficult questions. I think the Wasson selection task is surprisingly difficult. But there are also questions that we don't answer.

Thatic questions. Hey, what's up? I don't actually look up and tell you. I don't really. Well, you can't because you've got top-shelf vertigo. I can't, exactly. Just like everyone, when I'm asked what's up, I go, oh, not much. Or I'm doing well.

But there are also answers we don't question. And I think we've kind of like been talking about this already. It's that a lot of the conclusions and things we believe, we just kind of don't want to question them. We don't feel motivated to find counter examples and falsify them. Are you talking about like social norms, like social rules here? That's right. I'm talking about social rules and taboos. And I know that you are familiar with these because we've both read this book.

Jonathan hates the righteous mind. It's so good. Which way? There. It's so good. It's so good. It's spicy. It's spicy. It's spicy. It's spicy. And we're not going to discuss it today, but we are going to put a little worm in your brain. You've got to be careful now, though, Michael, because if this section that you're, if you're going to the very first example, if you, if this gets clicked up and does the rounds on the internet, you could, your reputation could be really in trouble. I know. Look, I'm picking, I'm picking the safest one. I'm picking the least spicy one. And I, I, I, I,

Again, I think that Hannah, we should just bring this up. And then in a later episode, we'll talk about moral reasoning. Good idea. Which is not much different than reasoning about obligations or abstract mathematical things. It all kind of points in the same direction. But this is one where you really, you really wind up realizing that you had a conclusion before you had any reasons. We should say, actually, just in general, this book, this book really interrogates in an extremely careful and logical way, a lot of the moral rules that we fully accept as a society.

Things that we find abhorrent, things that we find disgusting, it really tries to understand what is it about that that we have decided is unacceptable. That's exactly right. And it really looks into why we don't agree on what is acceptable and disgusting and good or bad. How complex our reasons are. It's called The Righteous Mind by Jonathan Haight. That's right. And I think it's a very insightful book that's perfect for the way the world is today. But here's an example of a question.

And I want you to, I'm just going to read from chapter one. I'm just going to read the first paragraph. Good idea. Good idea. I'm going to tell you a brief story. Pause after you read it and decide whether the people in the story did anything morally wrong. A family's dog was killed by a car in front of their house. They had heard

that dog meat was delicious. So, they cut up the dog's body and cooked it and ate it for dinner. Nobody saw them do this. Okay, so no one saw them do it. The father, let's say, was a professional butcher

and none of them got sick. The dog passed away due to an accident. Was already dead. Already dead. And you know, what afterwards the family was really glad they did it. They felt that it was respectful and it made them feel closer to the dog. So did anyone do anything morally wrong? That's our question to you. Let us know in the comments below. And I don't know when we'll talk about this. There's a lot that I want to learn and that we both should talk about before we do it. We'll look into moral reasoning.

Yeah. I think that's a really good idea. We can read you more examples from that book. As long as you promise, audience, not clip it up and share it around. as though it's things we actually think is, I mean, yeah, he tests the bounds. But that is a really great example, a really great example of it definitely feels wrong, but it's quite hard to say why. Exactly. These are Jonathan Hates, what did he call them? He called them harmless taboo violations, where he knows that there's a taboo and he believes

that it's like this almost intuitive thing where we believe it and we provide reasons after the fact. So he constructed these questions where all the typical harms and reasons people give for the taboo have been canceled. They've been clipped. That's not in this case, not in this case. They didn't kill their dog. They just ate it after it accidentally died. Nope, no one got sick. No one saw them do it. Blah, blah, blah, blah, blah, blah. And you're left going, but I still think it's wrong. But he's taken all the reasons away because you never needed the reasons in the first place to believe what you believe. You were using the reasons in order to justify your instinctive reaction. That's right. But we're saying too much. We're going to leave it there.

If you guys have any questions for us, any despicable, disgusting, perverted moral quandaries, email them right over to us at the rest is science at goalhanger.com. Absolutely. And in the meantime, you can check out our newsletter, which I really should have learned by now, but I think it's therestes.com forward slash science. And we will see you on our episode of field notes that's coming up later in the week. And yeah, send us in everything. You're like, put in the comments also whether you actually got the puzzle right at the very beginning. And all of those of you say that you didn't, I was joking, you can carry on this thing. All right, take care, everybody.