From the Vault: Illusory Truth Effect, Part 1

some of your your foundation stones. I think you know, this one's gonna make you rethink the way you interact with with the world and how you interact with truth. So, uh, you know, it's maybe a harrowing journey at times, but I think you're gonna emerge on the other end stronger. And Part two will come a week from today. Your today, not our today, as we record this. Welcome to Stuff to Blow Your Mind from how Stuff Works dot Com. Hey, you welcome to Stuff to Blow Your Mind. My name

is Robert Lamb and I'm Joe McCormick. In today, we're gonna be talking about one of our favorite subjects, our tendency to believe things that aren't true now, Robert, I wonder is there a false factoid or claim that you just always find yourself recalling as true even though you've checked it before and discovered it to be false in the past. Yeah, this is an interesting question because I feel like there are things that come up in research

all the time, certainly key things over the years. Uh, you know, as we research and riot different topics where I have to correct on, you know, where I think I knew something and then I'm like, oh, well that's that's actually now that actually do the research, it's not not a not a fact. And then then you know, the same goes for false beliefs, that beliefs that they creep in the sort of Mandela fact type of scenario.

For instance, there was a time when I thought Gene Wilder was dead prior to his actual death, and then as he actually dead now he is actual really dead now. So I thought he was dead before he was dead exactly because and I think it was just a combination of he was not as active anymore, and I wasn't really keeping up with the Gene Wilder filmography and like current events related to Gene Wilder, and something maybe I picked up on some news piece at some point, and

somehow he got clicked to the dead category. And then when I found out he was alive, it was it was really like he came back to life. And I had the same thing happened literally just the other day with a standout comedian, Larry Miller. I don't think I remember who that is. Oh. He he had to kind of you know, dry observational comedy he had. I think he still acts, but he would show up on say night Chord. I think, oh, wait a minute, is seeing

some Christopher guest movies. He may have been, Yeah, but for some reason years ago, I got into my head that he had passed away, and so occasionally I would think of Larry Miller and was like, oh, yeah, I remember Larry Miller. Too bad he passed. And then I actually looked him up the other day and it turns out he was not passed away. He's still very much alive and active. And I was just living in this

fantasy world of dead and Larry Miller's. You know, I have false beliefs that recur with much more significance, like I keep remembering that, Yeah, maybe it's just because I was told this all the time when I was a kid that vitamin C supplements will ward off colds. That is not experimentally proven. That that is like not a finding of science. And yet I just always if I haven't checked in a while, it just seeps right back in, like, yes, that is true, vitamin C it'll keep colds away. Well,

it's easy to fall into the trap. I do this all the time with with various vitamins and some supplements where I'm like, I don't know if it works, probably doesn't work, but I'm going to go and take it just in case, because it's it's vitamin C. You know, what's the what's what's the harm there? It's kind of like believing in God just in cases that he exists, believing in vitamins. Yeah, but then you end up with like a weird sort of vitamin tentacle going out of

your neck. And you didn't see that come digit, that's fake news. The Joe vidamin C will not cause a tentacle to grow out of your neck. But now you've heard it, it's true. Um. You know, I feel like there are things that have popped up where where I'll think, well, I've always heard X, but I've never actually looked it up. UM, And and then that's where the problem seeps in, you know, where I just I think I know something, but I'm

not sure, but I don't care enough to actually investigate. UM. There is one possible example that that comes up, and that is there was this, of course, the idea that George Washington Carver invented peanut butter. He know, he had something to do with peanuts. He had, so yeah, he was. He was. He is a famous inventor, important to African

American inventor. And I just I didn't know a lot about him, and I had always heard the peanut butter thing, but I didn't actually research until I helped my son with a class project about him earlier this year, and then I was able to definitely, you know, check that one off on the mental list, like, okay, this is the is this is false. He did not invent peanut better he did, but he did do stuff with peanuts, could do stuff with peanuts, but not peanut butter. Okay.

You know a huge place where you can see false beliefs persisting, UM is in people's beliefs about sort of like political facts or sociological data. A very very common one is people's beliefs about crime. I think it's because like crime is one of those like sensational types of subjects and makes people think about violence, images of blood

they see on the news and stuff like that. You know, poll conducted by Pew in the fall of get this fifty seven percent, So a majority of people who had voted or planned to vote in sixteen said that crime had gotten worse in the United States since two thousand eight by every objective measure. Exactly, the opposite is true.

That's just not true. FBI statistics, based off of like nationwide police reports, found that violent cry time and property crime in the United States fell nineteen percent and twenty three percent, respectively between two thousand eight and and so you think, okay, well, maybe that if that's just police reports, maybe fewer people are reporting crimes to the police, right, But also the U. S. Department of Justice Bureau of Justice Statistics does direct annual surveys of more than ninety

thou households to see about rates of crime that might not be reported to police. And quote the b j S state to show that violent crime and property crime rates fell twenty six percent and twenty two percent, respectively, between two thousand eight and so a majority of people are believing something that by every measure we know, is not true. Crime has gone down, and yet a majority of people believe it has gone up. And it's not hard to see why that might be true when you

consider like the political messaging of certain politicians. It's also you could also, of course think about just people negativity bias, right, the tendency to believe things are worse than they are in the broad sense or mean world syndrome looking at dangerous stuff happening on the news and thus having an overrepresentation of it in your mind. But I think we

would be wrong to ignore the effects of hearing specific politicians. Well, for for example, in twenty sixteen, specifically it was Donald Trump a lot talking about how crime is through the roof right, And and to your point, we can look to statistics on this. This is not something that is uh. That is just you know, in the ether, we have hard data. It's not a matter of opinion. It's just like every measure we have says that's not correct. But

what about other beliefs. I mean that that's certainly not in isolation. There are lots of cases where there are widespread beliefs in things that are just simply factually not true. Yeah, I'll run through a few here that that range and topic. For instance, here's a nice science related when to kick off with. In a two thousand fifteen Pew survey, only thirty percent of Americans knew that water boils at all

lower temperature at higher altitudes. Thirty nine percent said it would boil at the same temperature in Denver in l A, again Denver being at a far higher altitude, and had it reversed. So the majority, something like two thirds of

people were just flat wrong yes and uh yeah. And to put that in perspective with another science fact, most Americans in this two thousand fifteen survey correctly identified the Earth's inner layer, the core, as its hottest part, and nearly as many two knew that uranium was needed to make nuclear energy and nuclear weapons. Well, should we be comforted by the fact that that's what people know? I don't, like, they don't know much about water, but they know about

nuclear weapons. Well, I mean, on one hand, nuclear weapons was is and was more in the news. Uh, And then on the other hand, like the the inside of the earth is more engaging and and also completely on politicize. Uh, well, well water is not politically boiling point of water is

not politicized. But it's also not very sexy. I guess like it's it's it's one of those things where unless you're actively moving from low to high altitudes or you know, living part of your time and dinner from part of your time in l A, I guess it's it's very possible to live your entire life without really having any real world experience with the difference. Uh though, I do feel like if you read enough baking manuals, it comes up. Yeah, but maybe you just don't remember which way it goes.

I guess that you know one of the ones you've got here that that has come up many times in my life. It's come up enough that I know the right answer now. But the misconception that you can see the Great Wall of China from space, Oh yeah, this is one that I have to admit. I think I used to adhere to again without really referencing it, because it just it had that kind of truthiness to it, right,

and you want it to be to be real. The idea that that this this epic structure aided Uh, you know long Ago is visible from space, but it's actually been been disproven multiple times. It's it's only visible from low orbit under very ideal conditions, and it's not visible from the Moon at all. Because that's another version of it that it's that that the Great Wall of China can be seen from the moon. Yeah, I guess there are nuances to the word visible. What's what I mean?

But in the normal sense that you would mean it's not visible from space. Correct. Now a two thousand sixteen you gov poll, this was this is a UK group. They looked at how belief in pizza gate that thing, Yeah, how that shakes out across different voter groups. Now, that was this vast conspiracy theory people had about how there was a pizza restaurant in Washington, d C. That was like running child slavery rings that was linked to the

Democratic Party. Yeah, it had to do with an idea that Clinton campaign emails supposedly talked about human trafficking and pedophilia. And according to this particular poll, sevent of polled Clinton voters believed that that this was the case, this was a reality, and of Trump voters did um. And then there's another classic they looked out to to put this in perspective, the idea that President Barack Obama was born

in Kenya. Kind of alarmingly enough, across both groups of voters, both the Clinton voters and the Trump voters, they found thirty six percent believed it, despite the fact that that too, has been debunked time and time again. Yeah, I mean, it's crazy that these types of beliefs can catch on so well, especially like we we understand very well the way that political ideology and tribal thinking affects the way

we form opinions. Obviously, our our opinions are deeply informed by what people we view as are in group believe, and so we want to be in line with the in group and and stuff like that. But you also can't really ignore the fact that these are things that if you pay attention to certain sources, you're going to be hearing over and over and over again. And what effect that might have because it's you know, widely accepted fulk wisdom that if you repeat a lie enough, people

start to believe that it's the truth. Right, That's one of the things. I mean, I don't know, you've said it enough times that I'm already convinced exactly, I mean almost going along with this. Uh. There's a quote that often gets sourced to the Nazi propaganda minister, Joseph Gebbles. Uh. Some versions of the quote say something like, if you repeat a lie often enough, people will believe it, and you will even come to believe it yourself. I couldn't

find any evidence that just Gebbels actually said that. It seems to be a misattribution, but it's sort of a paraphrase of similar ideas that are, you know, within that that frame of thinking. Like Adolf Hitler himself wrote in mind comp quote, the most brilliant propagandist technique will yield no success unless one fundamental principle is born in mind

constantly and with unflagging attention. It must confine itself to a few points and repeat them over and over here as so often in the world, persistence is the first and most important requirement for success. So just the fact that Hitler said it obviously shouldn't make us think, well, you know, he's right with Hitler though. If if Hitler was good at anything, it was getting lots of people to believe lies. Certainly, so I think, because this is

such an important issue. And because widespread misconceptions are so common, and because they can, in fact, especially in some political circumstances, be so destructive, And because the repetition of lies and false statements in in at every scale of existence, you know, in in mass media and in our personal private lives, is so common, I think it's worth looking at the

actual empirical case. Is this true, the idea that repeating statements over and over does that actually change what we believe. It's one of those things that you know, it sounds so common sensical, you just assume it's true. But according to the logic we're using now, those are exactly the kinds of statements that maybe we should be careful about. Yeah, and I think this is an important important topic for

for everybody. I don't care who you voted for in any previous elections or which political party in your given system that you adhere to. I think if you're listening to this show especially, you want to think for yourself. You want to reduce the amount of manipulation that's going on with your your own view of reality. And and

and that's what we're going to discuss here today. We're gonna discuss the degree to which false information can manipulate our view of reality and ultimately, what are some of the things we can do to to hold onto our our our individuality and all of this exactly. So this is going to be the first of a two part episode where we explore the liar's best trick, the question of repetition and exposure in forming our beliefs and changing our attitudes. So that's going to be the jumping off

point for today's episode. Does exposure and repetition is hearing a claim and hearing it repeated actually have the power to change our beliefs? Or is that just unverified folk wisdom? Yeah? And and of course it goes it goes well beyond politics. It also gets into marketing. You know, we've we've touched on the manipulative nature of marketing and advertisement on the show before, and it's always one of the things you always come back to. It's always about messaging, right, Like

what is the message of the product? What's the message of the ad campaign? And how they just continue to hammer that home. Why do brands have slogans? Yeah? Why don't they just tell you a positive message about the brand that's different every time? Why do they tell you

the same message in the same words in every commercial. Yeah, why did those fabulous horror trailers from the nineteen seventies say the name of the film eighteen times, don't go in the basement, don't go in the basement, No one, no, just seventeen will be admitted. Yeah, it's all. It's all kind of part of the same situation. All right, Well, we're going to take a quick break and when we get back, we will dive into the research in the

history of psychology about repetition and exposure. Thank you, thank you. All right, we're back. So the first question we're going to be looking at today is whether anyone has actually studied this question, this question of whether exposing people to acclaim and then repeating the claim makes them believe it, Whether anybody studied that in a controlled scientific context. And the answer is a resounding yes. There are I think

dozens of studies on this subject in various forms. Probably the flagship study on this, the first big one that everybody sites that that really got people into the subject, that got the ball rolling on it was from ninety and it was by Lynn Hasher, David Goldstein, and Thomas Topino, and it was called Frequency and the Conference of Referential Validity in the Journal of Verbal Learning and Verbal Behavior,

And that was as I said in nineteen seven. So the authors start out in the study by talking about how most studies of memory that take place in the lab involved useless or meaningless information units. So researchers, for example, might try to see how well subjects remember a phrase like I just made this up. The purple donkey was made of soft spoken muscular elves, Like, can you remember that word for word? The purple donkey was made by

muscular elves. Now, now you're close, not made of Yeah, it makes a lot more sense to say made by wow. But I see, I've already missed up the origin story of the purple donkey. Statements like this have no importance in the real world, and part of what they were talking about is that we're testing for memory and things that don't have any validity to reality. Um. So the authors write that they're curious about what kind of processing subjects do with information units that might have validity in

the real world. For example, factual statements like quote, the total population of Greenland is about fifty thou which at the time of the study it was. I checked, though, that seems like a lot more people than should be in Greenland, right, I was. I was surprised by that. Well, but I would agree based on I'll be a limited amount of of information that I've I've read and viewed

about Greenland. You know, you typically, in my experience, Greenland shows up in nature documentaries, and of course you're going to see rather barren uh locations in those films. Well, greenlanders out there in the audience. Let us know if you're listening, what's life like up there in Greenland. I'm

interested now. But anyway back, So, yeah, population of Greenland at the times about fifty and so statements like this both refer to something that could be true or false in the real world, and there are also things that people are probably uncertain about, like do you know what the actual population of Greenland is? I didn't know before I looked it up, And so we know that the statement is either true or false, but we aren't sure

whether it's true or false. And of course, to go back to a previous episode, you're kind of anchoring my expectations by throwing out without any population data in my head about Greenland, like that's suddenly all I have to go on, Oh yeah, that's interesting. Also, so like it could be three thousand or it could be like a million, and either you're sort of moving your guests range toward fifty.

So the thing they point out is, even though most people don't know what the population of Greenland is, we're often willing, into some extent able to make guesses as to whether statements like this are true. So where does this semantic knowledge come from? When we feel like we have knowledge to offer a guess about what the population of Greenland is even when we don't really know what

is that what allows us to judge these questions? And the authors note that frequency is a really powerful variable in all kinds of judgments we make about the world. So they hypothesize that quote frequency might also serve as the major access route that plausible statements have into our pool of general knowledge. So the idea is that we build our knowledge base based on how frequently we are exposed to ideas. You hear an idea a lot, and

that gets reinforced in the knowledge base. You've never heard an idea before, or you don't hear it a lot, it doesn't get reinforced, and it doesn't exist in the knowledge base. So here's the experimental part. Researchers came up with a list of a hundred and forty true statements and false statements, crafted so they all sound plausible. Yeah, they could be true, you know, the average person would

be unsure whether or not they're true. And the statements were on all kinds of subjects like geography, arts and literature, history, sports, current events science. A few examples of true statements included things like Cairo, Egypt has a larger population than Chicago, Illinois, and French horn players get cash bonuses to stay in the U. S. Arm True. Well, i'd see it. I should have joined the army after all. See, I was a french horn player really in high school. Yeah, I

didn't know that. What's it like playing the french horn. It's just, you know, there's a lot of spit and a lot of shoving your hand up horns. That's it. Otherwise it's like playing a trumpet. Now. See I actually played trumpet, and it's a lot less fun than what you're describing. Yeah, I mean, I don't know. There is an elegance to the way you hold it, and you again, you have your hand in the inside the horn. I don't know. Being a trumpet player to me always felt

like being a person who's complaining at full volume. Yeah, yeah, there is. There's more of an outward stance with the trumpet, right, you're blasting outward, But in the French horn, you it's it's more like you're playing music into yourself. That's quite beautiful, more beautiful than any music I ever played on the French horn. Uh So we got to get back to the study. Okay, so that's that's supposedly true. French horn players at the time got cash bonuses to stay in

the U. S. Army. Examples of false statements where things like the People's Republic of China was founded in ninety seven it was actually ninety nine. Or the copy bara is the largest of the marsupials. That's not true. The largest marcipial is the red kangaroo. The largest known in the fossil record is this thing called the extinct dip protodon. Now that in the capy bar is a rodent, right, I only is the capy bar and marsupial. I didn't even look it up. I only know that because I

go to a lot of zoos these days. But it is a mammal, it's a it's a rodent. It is a mammal, and it is a rodent, not a marsupial. Well, there we go. So it's wrong in multiple ways. So you got this big list that came up with of true and false statements, and all of them should sound plausible to the average person, But most people are not going to be likely to know for sure whether they're true unless they just happened to have some special random

knowledge or expertise. And so researchers held three sessions with participants, each separated by two weeks, and on each of the sessions, the participants were played back a tape of a selection of sixty recorded statements from that list, and the subjects were asked to judge how confident they were that the statements were true. And this was on a scale of one to seven, with like four being uncertain, five being possibly true, six being probably true, seven being definitely true.

And in each session, some of the statements were true, some were false. But here's where the real magic happened. At the second session and the third session, each time subjects got a mix of new true and false statements that they've never seen before, plus true and false statements that they had already seen in the previous sessions. So while most of the claims they saw were new, a

minority got repeated each time. And what the researchers found was that whether a statement was true or false, the more times the students saw it, the more they believed it. So again, this would be this, this, this would be the principle in action. The more they're hearing this, uh, this this false fact, the more they're coming to believe

that it is true. Yeah, even in this constrained, kind of weird experimental context where they're aware that some of these facts are going to be false, it's not like they're being told this persuasively by a person trying to convince them. They're just reading this from a list of statements that are known to be either true or false. I mean, there's no there's no persuasive aspect to this at all, right, Right, These are not politically charged or

really charged by worldview at all. They're they're just plain neutral statements that really have very little interest to most people. Also probably, but what happened was whether the statement was true or false, people believed it more if they saw it more times. So I've got a little chart in here of what happened with the false statements. You can have a look at Robert as you can see the

new false statements. The false statements people saw for the very first time covered around, you know, like four or four point one across all three sessions. That would correspond to people saying they're uncertain. I don't know. I don't know whether French horn players get a cash bone us for staying in the army and playing into the self

and sticking the hand up the horn. But in the second session there repeated false statements jumped up from about four point over four point one to about four point five, and then in the third session up again to about four point seven. And we only saw what happened with two sessions. Who knows what have happened what might have happened if you had continued adding more sessions. So just seeing a statement more than once appeared to make it

more believable even though it wasn't true. And the pattern was roughly the same for true statements, which isn't all that surprising since the experiment was based on, you know, statements that people didn't know whether they were true or false to begin with. So, the authors wrote in conclusion, quote, the present research has demonstrated that the repetition of a plausible statement increases a person's belief in the referential validity or truth of that statement. I don't know why they

had to say referential validity. They could have just said truth. And that's that's some science writing for you. Uh, in the truth of that statement. And indeed, the present experiment appears to lend empirical support to the idea that quote, if people are told something often enough, they'll believe it. Uh so, so yeah, this is this is the first real study to find this and a few other things

the authors thought were worth considering. Uh. The fact that this effect was displayed in statements from a big broad pool of different types of subject matter suggests this is not extremely context dependent. Right, It's not just going to be political beliefs that are subject to this. It seems to be all different kinds of statements in all different kinds of domains. Another thing they noted was that the

effect was present for true statements and false statements. Either way, if students saw the claims more often, they believed them with greater confidence. But another takeaway is that the effect is not huge for false statements. Three exposures was roughly enough to get you from I'm uncertain to it's possibly true. But as we mentioned before, how many this is just

two or three sessions right right? Who knows what what would have happened if maybe you had done this more times in a row, or if there had been other factors affecting whether people were likely to believe these things to begin with, say if they had valences to the person's political identity or something like that. Yeah, you know, as we're researching this into and discussing it, I couldn't help but think of notable examples of uh false stories

about generally like like celebrities from the past. And I'm not going to mention any of them specifically. Why not, Well, because you know they all tend to be a bit crude. There there are several of them about like carrying down various sort of you know, pretty boy rockers or actors

from the past, uh in in the in. The interesting thing about him is these are generally like pre internet um stories that had to circulate the word of mouth or I think in one case there was talk of like a whole bunch of of facts is going out in Hollywood where someone was just basically just wanted to take somebody down because they didn't like them. I remember, I think, like ninth grade here is starting to hear this bizarre story about rich your gear. Yeah, that's that's

the main one I'm thinking of. And I think it basically comes down to Richard Geary's is a handsome, successful guy and and for a lot of people, you want to like really you know, and knock him down or not you Yeah, and uh, and so when you encounter a bit of slander or libel like that, or uh, just a ridiculous story, you're going to be more inclined to believe it if you kind of want it to be true, right or if you or you're like, yeah,

let screw that guy. I'm gonna I'm gonna go ahead and believe this, or even if I don't believe it, I'm going to pass it on. But either way, whether or not you're predisposed to believe it's true, it looks like this initial study at least provides evidence that you

would be more disposed to believe it's true in either case. Like, so whatever you're starting point is it's gonna nudge you up, like if nothing else becomes word association, Like if you're not really a fan, say Richard Gear's work, uh, and you can't name your your favorite Richard Gear film off the top of your head, that might be the primary keyword that pops up when you hear his name. Yeah,

it could be. Uh. Yeah. So so this bizarre effect that we're talking about where hearing a fact repeated, even if you've got no good reason to believe it's true, just hearing it repeated causes you to be more likely to believe it. This came to be known first as the truth effect, and then later on probably a better title was the illusory truth effect. I think we should

use the second one because otherwise that makes it sound true. Yeah, it just makes it sound like yeah, if you if you repeat something, then it is then it is true. There is no question anymore. So. The basic version of

the illusory truth effect is quote. People are more likely to judge repeated statements as true compared to new statements, And another way of putting it is that all other things being equal, you're more likely to believe a claim if you've heard it before than one you haven't heard before, and the more times you you're the claim, the more likely you are to believe it. But so far we've just talked about one study, right, this this one nineteen seventy seven study, uh what we can call it the

Star Wars study. If you want the Star Wars study here. It's a fairly small sample, just one study. If you want to be skeptical and rigorous, maybe especially because this backs up ful quisdom, which is always something you should be careful about. We should see if the effect has been replicated by other researchers, and boy, howdy it has. That's right. This next one comes to us from nineteen seventy nine Journal of Experimental Psychology, Human Learning and Memory,

the work of Frederick T. Bacon. Yeah, this was called the Credibility of repeated Statements memory for trivia. So Bacon performed he was trying to replicate this this effect. He performed additional experiments to test the previous team's conclusions and

add some nuance. So his first experiment, you got ninety eight undergrads and they had two sessions in which they were asked to rate sentences as true or false, with three weeks between the two Sessions, and Bacon found that the repetition illusory truth effect was modulated by whether the subjects consciously believed that a sentence had been repeated. That is, if they remembered that they had seen the sentence last time,

they were more inclined to believe it. If they believed they were seeing a sentence for the first time, they were less likely to believe it. And this was true regardless of the statements themselves. I can't help but think of our modern version of this with Facebook feed right, because you're inevitably, if you're your Facebook user, or perhaps if you're a Twitter user or some other social media you're you're scrolling down right and there are a lot

of sentences coming at you. Some you just kind of read in passing. So maybe you don't read at all. But are you actually stopping to really think about what a particular headline or you know, or paragraph is saying or is it just kind of scrolling in the background of your mind. Yeah, And the result of this one experiment here would seem to indicate if it has validity, it would mean the ones you stop and pay attention to you and make a memory about are the ones

you're more likely to believe later on. But then also in another experiment, he had a group of sixty four undergrads and he replicated the illusory truth effect and found that students believed repeated statements to be more credible even if the students were informed that the statements were being repeated. So you can directly tell somebody, hey, I know, I just asked you if it was true or false that zebras could automatically detach their own tongues and fling the

tongues at attacking hyenas. I asked you that same thing three weeks ago. It may or may not be true, And even in this case, repeating the statement still makes them judge it to be more true than statements they're seeing for the first time. So you can warn people that something fishy is going on and they still fall for it. So you could you could straight up share a piece of just undeniably fake news on social media and and said, hey, guys, this is this is something news.

This has been totally debunked. Um, you can look it up on Snopes, etcetera. And that's still not going to completely disarm the piece that you're sharing. Well, we will talk so I would say, yes, we will talk more about that in the second episode where this kind of thing comes into conflict with real world beliefs. And just to be clear, I made up that zebra thing that that wasn't from the vacant study. I thought that would

be clear. But that's number one, not true. Number two, as far as I know, not one of the examples. Bacon used, Right, Well, I'm sorry you had to drag Zebras into all this. Joe. Well, you know, I like the idea of a weaponized tongue that's gonna go beyond the X Men. Surely that exists in reality. Well yes, but but not with Zebras. No. No, I guess that's amphibians and stuff. Okay, okay, So back to the study,

so Bacon says in his abstract quote. It was further determined that statements that contradicted early ones were rated as relatively true if misclassified as repetitions, but that statements judged to be changed were rated as relatively false. So even if you remember that you saw something before, you're more likely to believe it's true. It's kind of odd. That makes you wonder, what is the initial uh, what's the initial stimulus that caused you to misremember that you had

seen it before. Well, as we've discussed on the show before, I mean, there are multiple ways that false memories can be can be encoded. Oh yeah, absolutely. And so Bacon concludes that basically, people are predisposed to believe statements that affirm existing knowledge and to disbelieve statements that contradict existing knowledge. That's not all that unusual, right, But but it's specifically the repetition effect that seems to be playing a role here.

Let's take a look at another study. How about nine two Marian Schwartz Repetition and Rated Truth Value of Statements from the American Journal of Psychology. So Schwartz here has conducted two experiments on what psychologists were by this time calling the truth effect what we're calling the illusory truth

effect UM. So, experiment one, you get a group of subject and they rate claims on a seven point truth value scale, just like in the first study, the star Wars study, the seventy seven study, UM and a different group of subjects rated the same statements on a seven point scale of how familiar they were with the statements before the experiment started. How familiar are you with this repetition increased both ratings. So both pre experimental familiarity as

well as the perceived truth value. They both went up when people saw them more than once. That's not surprising. Again the replication, and then also the fact that you have seen something before, we'll tend to make you more familiar with it. Then you've got another experiment here. Second one replicated the illusory truth effect. Again found that it didn't matter whether you mixed up repeated statements that people had seen before with new statements or only showed them

repeated statements. Either way, belief and repeated statements went up. And this was done so that they could rule out the possibility they're thinking, you know, maybe it's only by contrast with new and unfamiliar statements that repeated one seem more credible. That is not the case. Either way you do it, if you've seen it before, you believe it more.

And so this study has taken as evidence that the feeling of familiarity with an idea might be an important part, or even the most important part, of how we judge something as true or plausible. But we should shift to asking the question of why why would increasing familiarity with the statement through repetition make it seem more true to us.

It makes me think about this passage from Wittgenstein in his Philosophical Investigations, about how absurd it would be to use repetition of a mental representation as evidence that the representation is correct. He writes, quote, for example, I don't know if I've remembered the time of departure of a train right, And to check it, I call to mind how a page of the timetable looked. Is it the same here? No, For this process has got to produce

a memory which is actually correct. If the mental image of the timetable could not itself be tested for correctness, how could it confirm the correctness of the first memory? As if someone were to buy several copies of the morning paper to assure himself that what it said was true. And that's that's kind of what we're doing. Like he's talking about mental images, But the general point is a

good one. We're essentially buying several copies of the same newspaper to to increase our belief that what the newspaper says is actually accurate. Now when it possible, interpretation that comes to mind is just like the idea of say,

walking us picking out stepping stones to cross a creek. Right, you step to one stone and it doesn't slip out from underneath you, and so you use that too to make your way across the other stones and hopefully make it across the entire creek without getting your feet wet or falling in being swept down stream to the to the waterfall. So to what extent are we just like

trusting anything that hasn't resulted in catastrophe thus fire. Well, I would say that it would make more sense for that to be true with sort of embodied physical, experimental knowledge about the world than it would for that to make sense for that to apply to semantic knowledge of things people tell us. Or maybe our brains just aren't good at differentiating between semantic knowledge that's imparted through words.

You know, maybe somebody saying all those stones will hold you up is encoded by the brain in sort of the same way as testing out one stone at a time. Uh yeah, I don't know. So this is what we should explore for the rest of the episode. I think, why should repeatedly exposing ourselves to the same information increase our confidence in it? If we didn't have good reasons to believe it the first time. It's clear that this is what's happening, But why does it happen this way?

All right, we'll take one more break and when we come back, we'll we'll jump into this. Thank alright, we're back. So we're asking this question of why repeatedly exposing ourselves to the same information would increase our confidence if we didn't have good reasons to believe the information the first time. It's clear from several experiments that this is what happens in our brains. If if a statement is repeated, we believe it more. But why do our brains work that way?

It doesn't necessarily make sense. Yeah, And one possible interpretation that came to mind is, of course we've touched on this before, that that we're all social animals. Yeah, so I've I've wondered if there this is a byproduct of the drive to fit in with a given group or tribe, that there's ultimately a survival advantage and getting along with the group, and so does that bleed over into highly

repeated or highly circulated lies or untruths. So basically like if there is a lie going around in the group. You'll get along with the group better if you just accept the lie. Yeah, And I'm not you know, certainly after looking at more of the research, I'm not arguing that that is the core um mechanism involved here. This is worth exploring that. But but I but I do like wonder to what extent that is that's playing a role.

Because you we we all have our our groups that we are involved in, our our our friends, our family, or our work groups, our social media groups are are sort of echo chambers that we find online. And uh, does it make you more susceptible to the lie just because there is this this ingrained need to fit in with that group too, to share the same values, and to put it on in the prehistoric framework, to to continue to have access to the fire and the and

the feast. Yeah, I think I think that's a possibility worth exploring. Let's let's take a look at it. Okay. Well, I started looking into this a little bit and I ran across a paper titled the Evolution of Misbelief misbelief misbelief from two thousand nine. This is published in Behavioral and Brain Sciences, and it was by Ryan T. McKay and Daniel Dinnett. Daniel Dinnett, all right, so they approached the following. I guess you could call it a paradox

in the paper. Given that we evolve to thrive in a fact based world, what other kind of world could there exactly? Yeah, I mean, we we're dealing with with actual reality here. But but given that we've evolved to thrive in this world, shouldn't true beliefs be adaptive and misbeliefs be maladaptive. It's clear that in many cases, probably most cases, that is the way things are. Right. Believing that you are able to fly off the edge of a cliff is not good for you. Believing that polar

bears want to cuddle with you is not advantageous. Holding false beliefs like this doesn't work out well for people. Yeah, they're they're they're reckless and dangerous misbeliefs that clearly like, if you've reached the point where you're believing in that, you're going to go extinct. So it's obvious that there is going to be at least some kind of major selection pressure in the brain for shaping brains that believe mostly true things, unless there are cases where believing something

that's false outweighs the negative the drawbacks essentially. So here here, here's what they wrote. Quote on this assumption, our beliefs about the world are essentially tools that enable us to act effectively in the world. Moreover, to be reliable, such tools must be produced in us, it is assumed by systems designed by evolution to be truth aiming and hence barring miracles, These systems must be designed to generate grounded beliefs.

A system for generating ungrounded but mostly true beliefs would be an oracle, as impossible as a perpetual motion machine. I like that. Yeah, So there's got to be like a grounding procedure through which we can discover true beliefs if we're going to have them. Otherwise we're just talking about magic. But we have to account for these varying levels of misbelief and self deception in the human experience.

They write, If evolution has designed us to appraise the world accurately and to form true beliefs, how are we to account for the routine exceptions to this rule instances of misbelief? Most of us, at times believe oppositions that end up being disproved. Many of us produce beliefs that others consider obviously false to begin with, and some of his form beliefs that are not just manifestly but bizarrely false.

How can this be? Are all these misbeliefs just accidents, incidences of pathology or breakdown or at best undesirable but tolerable byproducts. Might some of them contrat the default presumption be adaptive in and of themselves. I like this distinction they're making. I think this is actually useful. So they're breaking misbeliefs down into two basic kinds of categories, right

right that they're talking about. One those resulting from a breakdown in the normal functioning of the belief formation system. This would be delusions malfunctions, so things like face blindness or or catard syndrome. Okay, this is when the brain is creating incorrect beliefs because it's not working right, it's not doing what it's supposed to be doing. But then the second category are those that are arising in the normal course of that system's operations, So beliefs based on

incomplete or inaccurate information. These would be This would be a case of manufacture. And we'll get into examples of this in a second There could be tons of examples. One that comes to my mind that would be an example of this would be optical illusions. When you when you witness an optical illusion, you have a false belief that has been generated by your brain. But it's not because your brain is doing anything wrong. It's just because, like it's being exploited by a situation that's not part

of its normal what it normally needs to do. Right. Yeah, they point out that it's it's easy to think of these in light of of an artifact. Is it failing due to a limitation in the design in a way that is culpable or tolerable? Examples here being say a clock that doesn't keep time, keep good time versus a toaster oven that doesn't keep time at all. You can't expect the toaster of and to keep time unless it's

got a time right. Well, yes, so that's true. Yes, I would have said a purple donkey built by muscular elves that doesn't keep because you wouldn't even expect that's true? Yes now, But but it gets more complicated when you go into the biological realm, because what counts as immune function, dysfunction,

a pathogen infection, but what it would have. Ultimately, the immune system airs by defending the body against say, a transplant organ, and may ensure its survival because the body is going to reject that attempt to reject that that heart transplant, even though the heart transplant could save the patient,

will save the patients. So it seems like in order to understand this, you almost have to understand the context, right, right, They say that they invoked the work of Ruth Garrett Milliken, who in saying that we can't look to an organ's current properties or disposition, we have to look to its history. That makes sense to me. Organ transplants, of course, are not part of our evolutionary history. So this is just the body functioning normally in rejecting the invader heart. Right.

The body is not malfunctioning, is doing what it's supposed to do. We're just throwing a situation at it that it's not prepared to deal with. Yeah, so that brings us to the more human examples, you know, lies and uh and so forth. Oh, that's interesting. So a lie could be like a thing that our bodies were not really a prepared to deal with very well, which is weird to think of because of how common lies are. Yeah,

they right. However adaptive it may be for us to believe truly, it may be adaptive for other parties if we believe falsely. Now that, of course this is something Just to to interject here, I think this is something that we ultimately see holds holds true with other animals, like the role of deception of course in u in in in certainly in hunting and defense, in even acquiring mates, they continue an evolutionary arms race of deceptive ploys and

counterploys may thus ensue. In some cases, the other parties in question may not even be animate agents, but cultural traits or systems. Although such cases are interesting in their own right, the adaptive misbeliefs we pursue in this article are beneficial to their consumers. Misbeliefs that evolved to the detriment of their believers are not our quarries, so they stress the difference between beliefs and what they referred to

as a leafs uh and uh. For for instance, if I'm freaked out by tall buildings, I might not believe that I'm going to fall off, but I might a lieve that I'm going to fall off the leave as in like like a moral yes. Yeah, and in this case it seems to be something that is tall a

tolerated side effect of an imperfect system. But it's not McKay and dinn itt that end up bringing up the illusory truth effect, but psychologists Pascal boy Yer in commentary on the paper, Uh, this particular paper from from McKay and Dinnet, by the ways available online. I'll try to include a link to it on the landing page for this episode. But in his commentary, Boyer rights dramatic memory

distortion seem to influence belief fixation. For instance, in the illusory truth effect, statements read several times are more likely rated as true than statements read only once. People who repeatedly imagine performing a particular action may end up believing they actually performed it. Oh yeah, this is something I've read before. If yeah, if so? If you just like have people walk through a task in their mind and then ask them later if they remember doing it. A

lot of times they remember physically acting it out. Yeah, I've certainly had this occur with me, Like there'll be something I need to do and I'm thinking about doing it, and then I can't remember if I actually carried it out, and this is uh, this is called imagination inflation, He writes.

Misinformation paradigms show that most people are vulnerable to memory revision when plausible information is implied by experimenters in social contagion protocols, people tend to believe they actually saw what is in fact suggested by the confederate with whom they watched a video. So that he's just listing lots of the ways that we are end up with false beliefs. There's a plethora of examples of mechanisms for putting false

beliefs in our brain. Right. Yeah, I know there's a lot of territory covered in this paper in the attached responses, but I can't I come back to the sort of key reason that I sought it out, Like, like, when is self self deception helpful? Is it necessary for the deception of others? It doesn't quite seem to be, Like, you don't have to believe the lie yourself to tell someone else the lie, regardless of what telling the lie

repeatedly might do to you. Well, so, boy, he's skeptical of the idea, right, So is he basically saying, like, you don't want to overstate the the adaptiveness of believing lies. But yeah, he drives something that memory need only be as good as the advantage and decision making it affords. Okay, so he's essentially going for the byproduct thing for most most beliefs. He's he's saying like, look, you know, memory needs to do certain things, and in the course of

doing those things, it may generate some false beliefs. We don't have to assume that those false beliefs themselves are beneficial, right, Yeah, And and to come back to McKay and Dinnett, they point out that natural selection doesn't seem to care about truth. It only cares about reproductive success, so that there are various cases where a particular false belief or misbelief is

seemingly adaptive. You believe in a non existent fire god, Okay, but say that its laws inhibit overt selfish behavior that gets you in trouble and not work out for you in the long run. So in that case, you have an adaptive misbelief. Now, if the fire God wherever to actually appear, then this would be an adaptive belief. But then there are arguably a whole host of other false ideas that seem adaptive positive self deceptions about ability the

placebo effect for instance. Um, they bring up the self theories of intelligence, entity and incremental view of intelligence. Um. This being like, m Am, I born with a certain and uh intellect? Or do I develop it over time? And how those different core beliefs can affect your effectiveness in life Like doesn't mean like, oh, I've to work really hard in order to stay stay on top of this or is it a situation where oh, I'm I'm brilliant, I can accomplish anything. And and of course I think

you can argue for pitfalls on both sides. And of course there's always the optimal margin of illusion in play, which comes to us from Roy f Ball moister. Uh. And you know, ultimately crazy over confidence as we do, as we discussed, is going to lead to extinction. Right, you don't want to cuddle the polar bear. Right, cuddling the polar bear thinking you can fly? Uh, These are going to lead you falling off the side of a

mountain or winding up at a polar bear's tummy. Yeah. Now, I could certainly understand the idea of socially adaptive misbeliefs. I think that thing. Those things definitely do exist, and in some cases there might be some overlap with the types of things that get repeated so often, Like reasons for believing untrue things can also compound each other. I mean, I'm about to explain why I think false beliefs gained

through exposure and repetition are not adaptive in themselves. Uh, but you can have more than one reason for believing something that's untrue. Think about objectively untrue statements that get repeated, as we were talking about earlier in a political context. The evidence shows that we believe them partially because of how often they repeated, but there's also social cognition and

also identity protective cognition. In other words, we tend to believe things that members of our political tribe and social in groups say, and for social cohesion reasons that that is adaptive for us. We also believe things that validate our sense of personal identity. But I think it's pretty clear that that these types of effects can work in a nasty perverse tag team format, boosting and complementing one another.

But even if we we put aside these complementary effects, put aside uh, social and identity protective cognition, put those aside and just focus on the explanation for the illusory truth effect and repetition. There's a really interesting thing that comes out, and this is based on the idea of pros tessing fluency, which is it's a it's a concept that is way more interesting than the name would let

you real. So the dominant explanation for the illusory truth effect in the psychology literature, which we're about to get into, um, it fits into this byproduct category that we were just talking about. Based on all I read, it seems the informed majority opinion of psychologists is that the illusion of truth that we get from exposure and repetition is an unfortunate byproduct of generally useful cognitive heuristic. Now, a heuristic,

as we've talked about before, is a mental shortcut. It's a fast and cheap trick that the brain uses to arrive at a judgment or produce some kind of result without using too much effort. And it's it's worth driving home that our brains need fast and cheap tricks. Brains are very energy hungry. Yeah yeah, there's only there's only so much power to go around there, so it's uh, it's kind of has to hold everything together with a bunch of tricks. Yeah, so it works something like this.

Let's go on, let's go with it. Assume that on balance, true statements get uttered more often than lies. As cynical as we like to be, that's probably true, right, True statements are generally more useful to people. Also, there's a sort of convergence effect where there's only one way for a true statement to be true, but there are lots of different ways to say a lie about the subject of that statement. So like, true statements on a subject are going to be more consistent usually than lies about

the subject, because a lie about the subject could be anything. Well, and also lies lies it in large part have to be believable. Like think about the various true statements and uh and false statements that might be uttered during the course of a given day at work. Yes, somebody, hey, where's the bathroom? You know it's a new building. Say, then they're they're gonna probably say, oh, it's over there, and they're they're they're probably going to tell you the truth.

It generally does not serve people well to lie about the location of the bathroom, right, because you're gonna find out and then you're gonna say, hey, why did you tell me the bathroom is over there and not over there? Are you insane? But then some of the false statements you're liable to hear might be, hey, if you, uh, I don't know, let's see have you started on that report yet, Let's do on Friday, And they'll say, oh, yeah, I've got it, I've got it taken care of. I'll

get it to you on Friday. You know. There there's there are a lot of statements like that that are that ultimately you can't really check in on, like you're just gonna have to take their word for it. Then that kind of lie, yeah, you'll never find out, you know, yeah exactly. Or I can't come into work today because I'm sick, Well all right, I'm you know, we're not going to ask for a doctor's note. You might be lying, you might not, but it's just kind of a gimme

on that situation. Yeah, that's another reason that we're more likely to be exposed to true statements generally, or at least that were more likely to detect true statements generally, because false statements are harder to verify, usually by design of the person making them. So you're able to find yourself in an environment that's mostly built out of uh true statements and believable lies. Right, So, on this assumption, you know you're you're in a hurry, and your brain

it is not designed to consume infinite energy. It wants to try to be efficient. You don't have time to evaluate all claims rigorously. I mean, even no matter how skeptical you want to be, we can confirm this eventually. You are just not going to have time to look into everything you believe. You're just gonna have to take somebody's word for it. It's not practical to try to live by verifying every single belief. Oh yeah, I mean it would. You've just got to have something firm underneath

your feet in order to proceed. Oh yeah, you've got a bedrock. But then you've also got to have you just I mean, you take somebody's word on where the bathroom is, like, you're not gonna try to fact check them. You know, well, I guess you will by trying to go there. But other other things like that, mundane things people tell you throughout the day, You're just gonna have to believe them. There's just no, it doesn't make any sense to try to verify all of it because you

don't have time. So therefore, an easy shortcut for assuming that a statement is more likely true is have I heard this statement before? Statements they get uttered more often are more likely to be from that class of true statements. Okay,

I can roll with that. Now, there's another type of parallel thinking that says, uh, that says, you know, also, it's actually more difficult to disbelieve something than it is to believe it, because and I don't know if this is really confirmed or if this is just one theory about how the information processing in the brain works. But just as a quick tangent, there is a model of thinking that says, Okay, to believe a statement is true, To hear a statement and say I believe it is

just one step in the brain. To hear a statement and reject it as false is a two step procedure where first you have to hear it and believe it to understand it, and then you have to go back and revise what you just did and say, but it's not true. Yeah. It's ultimately like a king setting down at a banquet table, right, is the king to simply eat every Uh? Every food item on the plate and trust in it, and trust that he's not going to be poisoned or is he going to independently test each thing.

Has the food taster come up, put the mid transfer this gobblet of wine into the rhinoceros horn, etcetera. Hold the magic crystal over this plate of beans. And you know, another thing that came to mind was some of our discussions we've had in the past about consciousness and imagination as a simulation engine, that we use our imagination to mentally simulate possible outcomes so that we can best choose

how we're going to react to the world. And when I'm presented with something that might be a lie or or of some sort of untruth or a bit of of misinformation, I still can't help but imagine it, right, I'm having to create a mental picture of it. Um in a sense you're kind of believing it for the moment. Yeah, yeah, because I have to simulated in my head. And in cases of people who can form mental pictures, you have

to form those mental pictures. And uh, now you know, and I imagine a lot of this what shakes out after has to do with an individual's particular worldview. But I wonder if in some cases it's like a type one error in cognition, you know, it's a false positive. Uh uh that uh, that I I'm imagining this is a possible outcome, and then maybe I'm more inclined to believe it just so that I can keep it from harming me. Yeah. I think that's a very very reasonable

way of imagining it. But so here's where we get into the final part of our discussion today, which is the idea of what I mentioned a minute ago, processing fluency. So processing fluency just means how easy it is to process incoming information. And you wouldn't believe the research on how many of our decisions and mental outcomes seem to be based at least in part on processing fluency. The brain really really likes things to be easy. It really likes things to be to go smooth, to not be

too difficult. Uh So, to start off, based on existing research, it definitely seems true that people have an easier time processing statements and information they've heard before. In fact, Robert, you probably know this from direct experience. Like a familiar statement when used in the context of a sentence or an argument, is processed quite smoothly, but a new, unfamiliar statement in the same context often causes you to say, wait, hold on, back up, I need to wrap my head

around this. Familiar is easy, unfamiliar is difficult. But how would you test whether the ease of processing information we're actually affecting our judgment of the truth of a statement. And I want to get into a couple of quick, really interesting studies on this that we're so simple and

so brilliant. So in Rayburn Schwartz did a study and consciousness and cognition called Effects of perceptual Fluency on judgments of truth, and they took true or false statements, kind of like in the studies we've seen before of the variety osorn no Is in Chile or Greenland has roughly fifty inhabitants, and they presented those statements to people, and the main independent variable was that they presented the statements either against a white background, in a high contrast, easy

to read color, or in a low contrast, hard to read color, And apparently that made all the difference in the world. The idea is that the hard to read one has low processing fluency, it's difficult, and the easy to read one has high processing fluency. It's easy to process. And they found that this made a big difference in what people believed was true or false. Uh that quote.

Moderately visible statements were judged as true at chance level, whereas highly visible statements were judged as true significantly above chance level. We conclude the perceptual fluency affects judgments of truth. This is another one that makes sense from a marketing standpoint, right, just make your message very clear, very very easily absorbed,

and people will begin to buy into it. Oh. Absolutely, And this has actually been studied in marketing and consumer preference like there is one study from Novimski at All published in two thousand seven in the Journal of Marketing Research that in short, it found that consumers more often tend to choose brands that represent ease and fluency. Like say, if the information about a brand is easy to read, consumers are more likely to choose that brand that's the

one they want. So that makes me wonder why Coca cola is written in cursive. It's just like you would

want it just very clear, but old letters. Well, didn't they try to change the can when agod I haven't really looked at a can recently, maybe it's not incursive anymore, you know, they're Actually you might have two things in conflict, right, So you could have in conflict if you if you've got an old logo that people are familiar with, but it's hard to read, that the hard to read part might be undercutting their preference for it, but the fact

that it's familiar might be boosting their preference for it. If you try to change it to something that's easier to read, the change might introduce more difficulty in processing than the ease of reading would improve processing. Yeah, that makes sense, all right, So I want to cite one more study, a study by Christian uncle Bach in two thousand seven from the Journal of Experimental Psychology, Learning, Memory,

and Cognition. And uncle Bach does an interesting thing in the study where he's got a hypothesis he wants to test. He writes, quote, I argue that experienced fluency is used as a que in judgments of truth according to the cues ecological validity, meaning like successfulness in the real world. Quote. That is, the truth effect occurs because repetition leads to more fluent processing of a statement, and people have learned that the experience of processing fluency correlates positively with the

truth of a statement. So this is sort of what we were talking about earlier. It's a heuristic that you know, you're more likely to encounter true statements in the wild. People learn this through experience, and then they use the the the queue of processing fluency to to be the

judge of whether something is familiar or not. And if it's familiar and they get that processing fluency bump it's easy to process, then they're more likely to believe it's true because that's what has worked for them in the past. And if this is true, Uncle Box says, I bet I could reverse it with a little bit of training,

and he does. He's got an experiment where with a training phase he actually does three different experiments, and essentially what he does is that he trains people in a scenario where things that are easier to process, either because of being easier to read or because of repetition and familiarity. Either way, those things are more correlated with the thing with the thing being false, and when people get trained

in sessions like that, they lose the effect. So the good takeaway there is that if he's correct, it would probably also mean that your susceptibility to the lusory truth effect is dependent on what kind of environment you've trained in, and that you could potentially untrain yourself on it. But that would be hard to do because we all live in this world all the time where most of the time people are telling us true things, right, and and again, the brain is still going to need all of these

shortcuts in order to function properly. Yeah, exactly, But you could just be using the opposite shortcut, Like if you live in a world where people lie to you all the time. Uncle Bock's results here would suggest that you would eventually adapt to this, and you would instead become exactly the opposite. New claims you've never heard before would seem more true to you, and repeated claims that you're familiar with would seem like lies to you. Okay, so

there's hopeful us after all. Yeah, I mean, but we can't expect to live in a world like that, and we don't want to live in a world like like like that, Like you don't want to train your brain to live in a world where everything is assumed to be a lie. And make surely somebody has has considered exploring this in fiction. Yeah, it would be it would be a delicate affair to to really put it together and make it work on paper. But it's a world that I don't want to live in, but I kind

of want to visit fictionally. Oh yeah, i'd go there with you. That that's a good one to to come back to. But just as a quick note before we close out today, I think this idea of processing fluency is a really interesting one. There's tons of research on it, Like, uh, there is a study I found by Sasha Topalinski fromen in Cognition and Emotion about how processing fluency affects how funny we find jokes that apparently if a joke is easier to process, we've got high processing fluency on the joke,

we think it's funnier. I guess it just like feels good to get it without with less effort or something. Uh So there were multiple experiments, but basically here, let me let me give you a quick preview. I'm gonna say a word, Robert, peanuts. Do you like that word when you think about it? Peanuts? Peanuts? It's pretty good. It's it's not the funniest, where's no cheese, but but but I like it Okay, I just said that word.

So one example of this type of study would be if you prime somebody with significant nouns from the punch line of a joke fifteen minutes or even up to just one minute before you tell them the joke, people find the joke more hilarious. However, if you tell them a significant noun from the punch line immediately before the joke, they find the joke less funny, and the authors think this is probably just or the author thinks this is because if you tell them right before the joke, it

sort of spoils the punch line. But knock, knock, who's there? Cash? Cash? Who? No? Thanks? I prefer peanuts. Ah see, it works. It's not even aigg, not even but you already established peanuts, so it helped, right. I tried to let a minute or so elapse there. I don't know if it worked well. It's also complicated because we did bring up peanuts and peanut better earlier

in the episode. I didn't even think about that, but this actually I am not a student of stand up comedy by any stretch of the imagination, but I watching us stand up to see that just that that common structural tool that they use where you have the call back to a previous joke, and they'll often do it right at the end and then it's good night everybody.

That's the high note. And it it's not even necessarily like a call back to their to the funniest moment in the bit or the funniest bit in the in the stand up performance, but just the fact that they've brought your mind back to it. Yeah, it generates laughter, and it's the moment to end the show on. Yeah.

The theory is that it's it's very satisfying to have a joke that you've where you've been primed for the punch line already, because it's so much easier to get the punchline quickly and have that experience of familiarity in the yaha movement moment because when you say a word and then you say the word again later, the second time you hear the word, you've been primed, like you know, it's more fluid. So Yeah, I think that may very

well be going on with callbacks. Another part of the same study was that, like the studies we've been seeing before, jokes presented in an easy to read font were rated as funnier than jokes presented in a really hard to read font that's kind of not surprising, but processing fluency it plays into all this stuff like there is research about how opinions that are repeated more often, even just by a single person in a group, come to seem

more prevalent in a group. So you've got ten people standing around, then you've just got Jeff over here, and Jeff keeps saying the same opinion over and over again, even if you're aware it's just Jeff saying it in the end, if he does that, you will think that that opinion is more prevalent in the entire group the more people hold it. Well, that would make sense. You have one person in a group who say continually trashes on the movie Aliens. Oh no, why would that happen?

I don't know, but let's say it it happens. You know, I could see where it could reach the point where you're kind of like, I don't really know how I feel about Aliens now, because I sure do here here Jeff uh talking trash about it all the time. Or you could walk away from it being like, man, I don't understand all these people who hate Aliens, even though it's just one person. Yeah, that that seems to be something that would go on. Processing fluency also appears to

have something to do with aesthetic pleasure. There's been a lot of research and theory about this that that's a major component of what feels aesthetically pleasing to us is based on what's easy to process. Another part is that processing fluencing fluency apparently affects how credible a face looks. So if are you going to believe somebody, well, it turns out if their face is easier to process, especially because you've seen it a bunch of times before, you're

more likely to believe it. Even if they're not famous and they're not somebody you know, they're not like somebody you've had experience with that you can you know, judge their credibility just random faces shown to you in different sessions of an experiment. If you've seen them before, they're more credible. Of course, that reminds me of various experiments over the years involving the believability of people with beards.

People with facial hair or beards harder to process. They have I have not looked into it recently, so I don't know if there any are recent studies that that the crack this nut. But but there there have been studies that have looked in the past where they make the argument that, yes, an individual with a beard, you're going to have a little more distrust towards them. Well, obviously nobody should trust me. Well, no, we trust you because we know you. Joe. Yeah, do you really? Do

you ever really know someone? Well, I'll tell you one thing I know, and that's peanuts stuff. You got me, You got me there, you made me laugh and my joke didn't make you. Okay, Okay, So we gotta wrap up there. We've gone long here, but so we'll be back in the next episode to explore more recent findings and some of the ways that the illusory truth effect really does matter in our in our political and social world. Um, but so main takeaways I would say today is that

the illusory truth effect is real. Exposure and repetition really does change our beliefs. The illusory truth effect is small, meaning it doesn't automatically overwhelm other criteria in our decision making and judgment. In fact, in many cases it appears that there are not a statement is actually true is more important to our judgment than whether or not it's repeated or made easier to read, or any of these

other processing fluency boosts. But on average, over lots of repetitions, it's easy to see how this could have a big effect, especially when you bring it back to propaganda purposes on things we believe as a society, things that shift voting patterns in small but significant ways, and stuff like that. Yeah, that's the key. That it's not occurring within a vacuum. It's uh, it's it's it's affecting and being affected by all these other um mental processes and factors that are

affecting our decision making and worldview totally. But we will get more into that in our next episode. In the meantime, be sure to check out all the episodes of Stuff to Blow Your Mind at Stuff to Blow your Mind dot com. That is the mothership. That is where you will find everything, as well as links out to our various social media accounts. If you want to support the show, we always urge you to leave us a positive review, leave us some stars or whatever the rating system is.

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