Dr. Jud Brewer (4:31)

Thanks for having me.

Mike Carruthers (4:33)

So the experience of eating when you're not hungry is something I think everyone's had. I know I've had it and wondered, even in the moment, like, why am I eating this? What's the point? I'm not hungry, but it's hard to stop. So what is it that's going on here?

Dr. Jud Brewer (4:50)

Yes, it's kind of a misappropriation of a very helpful survival mechanism. And what I mean by that is that one of our most fundamental survival instincts is to eat when we're hungry. And it's set up based on a learning process called reinforcement learning, which is pretty simple. And it kind of goes like this where imagine our ancient ancestors out on the savannah foraging things, would see some food, they would eat the food, and then their stomach would send this dopamine signal to their brain that said, remember what you ate and where you found it. And that is the basis for what we now call in modern day, positive and negative reinforcement. The Same processes at play. When we're learning how to avoid danger, we remember where the danger is, we learn to avoid it. So these processes very helpful from a survival standpoint. Yet our very smart brains start learning, oh, wait a minute. Well, I can use the same negative reinforcement process, for example, when I'm bored. So if I'm bored, that doesn't feel very good. Which has the same flavor of danger, right? Danger is unpleasant. And then when we're bored and we eat something, we learn, oh, eating something, you know, distracts me from the boredom. And so we learned to kind of avoid boredom, so to speak, through negative reinforcement. So we learn to eat when we're bored. Then, you know, that nuances into stress eating and comfort eating and, you know, eating when we're lonely and all of these things. And on top of that, the positive reinforcement process kicks in when we learn to associate positive things like celebrations with food. And so we start eating at a retirement, you know, for a colleague or at a birthday party or something like that, even when we're not hungry.

Mike Carruthers (6:42)

So what I wonder about if that is all true is why this is happening more now than in the past. If you look back at the 40s and the 50s, people weren't so heavy. They must not have been eating so much. What's going on now that wasn't going on then?

Dr. Jud Brewer (7:02)

That's a great question. There are a couple of things at play. One is, and it's interesting that you mentioned the 40s and 50s, because that's when people started developing packaged foods where before that you basically had to make food from scratch and then it would go bad in a little while. So we've moved more and more away from eating, you know, whole foods that's minimally processed and more toward processed food. And I'd like, I'd, I'd like to call them food like objects. So things like Doritos, where the onion had this great satirical headline where they said, doritos celebrates its one millionth ingredient. And these things are not only designed for convenience, where we can have bite sized pieces already, you know, ready for us. We don't have to cut anything up, we don't have to prepare anything. And they can be in our drawer for a thousand years. They'll still be, you know, they'll still be good. But on top of that, the designing has gone toward things like bliss points and vanishing caloric density to make food more addictive.

Mike Carruthers (8:10)

So explain what you mean by bliss points and vanishing caloric density.

Dr. Jud Brewer (8:15)

So a bliss point is, I think it was Actually developed by food engineers. And what that describes is the perfect balance of salt, sugar and fat for that kind of jacks, our dopamine system the most, you know, so think of, you know, people trying to dial in different types of ice creams or things like that, where ice cream is basically, you know, sugar and fat with a little bit of salt, and then you put in a pretzel, you know, into that, where you get a little bit of crunch and you get more salt. So you can, you can think of that list point as ways to really try to maximally get people addicted to food and vanishing caloric density. A good example of that is a cheese puff or a Cheetos where you eat something and then it disappears in your mouth without you having to chew it or swallow it. And your body gets really confused and says, didn't I just eat something? And your mouth says, well, there's nothing here. And so that gets our fools our bodies and tricks our bodies into eating more.

Mike Carruthers (9:20)

So help me understand then what, why it doesn't affect everybody. There are plenty of people who are not overweight because of these convenience foods, junk foods. There are a lot of people who resist that. So why is that?

Dr. Jud Brewer (9:37)

That's a great question. And I think, you know, I don't think anybody has a super clear answer on that. There are a lot of different variables that go into that. You know, somebody's genes play a role, somebody's environment plays a role. How they've learned to associate food with different moods plays a role. So, for example, if somebody has learned, you know, if they have anxiety or depression and they've learned to eat as part of that, you know, that's different than somebody that's, that's not feeling anxious or depressed.

Mike Carruthers (10:10)

Doesn't it seem like part of this equation has to be willpower? Because you've got people who are all exposed to the same food. That same food is available to everybody. A lot of people eat that food. But don't overdo it. And some people do. So isn't willpower playing a role here? Some people can resist overeating and some people can't.

Dr. Jud Brewer (10:34)

If only it were that simple. So if it were a willpower problem, we wouldn't have things like yo, yo dieting, where people say, oh, just follow this recipe, follow this diet, follow this number of calories, you know, exercise this amount. And then we would be learning to train and optimize willpower. People have been struggling to optimize willpower for a long time. And I think we have a better answer as to why that's the case. Now, from a neuroscience perspective, willpower is more myth than muscle. If you look at the equations for behavior change, they don't include a variable for willpower. So neuroscientists don't even talk about willpower because that's not what drives behavior change. So I think it's a nice story that we tell ourselves. You know, oh, there's something wrong with me. I just need more willpower. Other people can do it, but when you look at the science, it's not a story of willpower. It's actually a story of reinforcement learning. But it just.

Mike Carruthers (11:36)

I don't know, it just seems like. And, you know, you tell me I'm wrong, but it seems like, you know, I could put a plate of cookies in front of two people, and one person would go, oh, yeah, thanks. I'm not really hungry, but I should. I know I shouldn't, but. And the other person says, no, thanks. No, not interested. Not really hungry. No, thanks. That looks like willpower to me.

Dr. Jud Brewer (11:56)

It can look like. Yeah. And the thing is, you don't know what's going on in somebody's head, so, no, thanks. Could be somebody gritting their teeth and really struggling and trying to keep themselves from eating something, or it could be somebody mentally imagining what it's like to eat that and then determining that they're not hungry and not eating it. And that's actually what the. You know, we've done a bit of research over the last decade now with this type of experience and others have as well, and it turns out that we actually predict what we're going to do in the future based on past experience. And we simulate doing an experience before we do it to make a decision that doesn't have anything to do with willpower. It has everything to do with how rewarding an experience was in the past and how accurate that simulation is so that we can determine whether we're going to do it again or not, and that. That's really about reinforcement learning, so. Well, I'll just give you an example from an experiment that my lab did at Brown University now a couple of years ago, where we had people use this app called Eat Right Now. And we embedded a tool where we had them imagine eating an amount of food that they used to eat in the past as they had a craving to eat food. We'd have them imagine going through the exercise of eating it, and then if they were still, you know, if they really wanted it at that point, we'd have them go ahead and Eat it. But we'd have them pay attention as they ate. And what we found was that through this exercise, it only took 10 or 15 times for somebody to change that reward value in their brain below zero, where it dropped below zero. And they would shift that behavior all through just having that reward value change in their brain. And the way that works, it's called positive and negative prediction errors. If we have a certain reward value set up for, say, eating chocolate cake, and let's say we go into a new bakery and we have to learn, is their chocolate cake good? So we eat their chocolate cake. It's like the best chocolate cake we've ever had. We get what's called a positive prediction error. It's better than expected. We get a dopamine spritz in our brain and we learn, oh, this is good cake. On the other hand, if it's crappy, we. We learn, we get a negative prediction error. And we learn, don't go back there. Our brain is doing this all the time as long as we're paying attention to what we're doing. So if somebody pays attention as they overeat, it doesn't take long for their. Their body to register, hey, this doesn't feel very good. And for that to change that reward value in their brain of overeating, again, I said 10 to 15 times. Once that, you know, once somebody gets that signal and gets it pretty clearly and it's consistent, that updates those predictions in their brain so that the next time, as long as they're paying attention, the next time they go to overeat, their brain can simulate, what's this next bite going to be like? Oh, it's not going to be so great. And then it makes it easier for them to stop. So bringing that back to your cookie example, if somebody is not hungry, right, and they have eaten cookies in the past when they haven't been hungry and it hasn't been a great experience for them, you know, cookies might taste good, but I don't know about you. For me, I get a sugar rush and crash, and it's just not worth eating cookies when I'm not hungry. So I could simulate that. And it's much easier to say, no, thanks than to try to force myself not to eat the cookie.

Mike Carruthers (15:28)

We're discussing the issue of eating when you're not hungry. And My guest is Dr. Jud Brewer, professor at Brown University School of Public Health and author of the Book of the Hunger, why We Eat When We're Not Hungry and How to Stop when they were Young the five members of an elite commando group nicknamed the Stone Wolves raged against the oppressive rule of the Kratarakian Empire, which occupies and dominates most of the galaxy's inhabited planets. The Wolves fought for freedom, but they failed, leaving countless corpses in their wake. Defeated and disillusioned, they hung up their guns and went their separate ways, all hoping to find some small bit of peace amidst a universe thick with violence and oppression. Four decades after their heyday, they each try to stay alive and eke out a living. But a friend from the past won't let them move on. And neither will their bitterest enemy. The Stone wolves is season 11 of the Galactic Football League science fiction series by author Scott Sigler. Enjoy it as a standalone story, or listen to the entire GFL series, beginning with season one. The Rookie Search for Scott Sigler S I G L E R Wherever you get your podcasts,

Kit Yates (16:46)

if Bravo drama, pop culture, chaos and honest takes are your love language, you'll want All About TRH Podcast in your feed. Hosted by Roxanne and Chantel, this show breaks down Real Housewives, reality TV and and the moments everyone's group chat is arguing about. Roxanne's been spilling Bravo tea since 2010, and yes, we've interviewed Housewives royalty like Countess Luann and Teresa Giudice, smart recaps, insider energy, and zero Fluff. Listen to all about tragedy podcasts on Apple Podcasts, Spotify, or wherever you listen.

Mike Carruthers (17:15)

New episodes weekly. So Judd, when I think about it in the moment, I realize that, you know, if I'm going to eat a piece of cake, the first bite's gonna be the best. And the second bite doesn't make the experience twice as good, that it quickly plateaus. It levels off, but it can still be very hard to stop. So for example, okay, I like Trader Joe's Dark Chocolate Peanut butter cups. They are one of the best things on earth. But when I eat one and it's very good, the second one isn't like doesn't make the experience twice as good.

Dr. Jud Brewer (17:53)

It's just.

Mike Carruthers (17:54)

But sometimes I'll eat a second one just because, well, it's there and so I eat another one. And yeah, it's good, but it's never as good as the first one. And I wonder why am I eating this? But it's hard to stop.

Dr. Jud Brewer (18:09)

You're actually describing the pleasure plateau. So I don't know how many cups come in a package that for, you know, for example, if you ate 1 versus 2 versus 3 versus 5, my guess is you could map out not Only that plateau where it's. It's not as good, right? Still, same same food, but it doesn't taste as good because our body's saying, hey, I'm getting too much here. And then at the end, so it flattens out, and then we go off of what I call the cliff of overindulgence when we've eaten too much and we're like, oh, why'd I do that? So you're actually describing what our body is really good at doing as long as we're paying attention. And what our body's really good at doing is telling us when we've had enough. Right? Now, that's different than saying, oh, why did I eat three? My guess is, and this is an experiment anybody can do for themselves, is the next time you go and eat those. I like to have people use this experiment where I say, you know, ask yourself with each bite, is this bite better than the same as or worse than the last one? And when it gets to the place where it's just the same as or even starting to get to the worst than what happens when you stop? Does it feel better to stop than to keep going? And somebody, they might have to do the experiment, well, what's it like when I stop this time versus what's it like when I keep going? They'll collect those data points and they'll see which one is better for them. Typically, it's when we stop. It's not when we overindulge. Overindulgence doesn't feel good. And our body tells us that. And then we learn, hey, it feels better to stop. And we get a bonus out of that, which is we have more of those cups for later.

Mike Carruthers (19:52)

I like that idea. Yeah, I think that's a really. I'm going to try that. Probably not with peanut butter cups, though. Something I like a little less because I don't want to screw my. That's one of my joys in life kind of thing.

Dr. Jud Brewer (20:04)

Well, I'll just highlight here. This actually helps us enjoy the food even more because your body says, yes, this is optimal. I love this. And when you pay attention, you enjoy every bit of it. And then when it becomes less enjoyable, you stop right before you stop, right before it becomes less enjoyable. So you actually stop at the peak. That's optimal. So I would say do it with peanut butter cups. You might actually enjoy them even more.

Mike Carruthers (20:32)

But there are times when I can think of other food I like. Maybe it's willpower, but I'll eat it. I'll want more of it. I know I shouldn't and I stop, but I really would rather in the short term, later on I'll be glad I didn't. But in the short term, I really would like some more, but I don't because I know that's, you know, that's not a good thing.

Dr. Jud Brewer (20:56)

Well, and this is where we can ask the question, what do I need as compared to what do I want? And so by asking that question, we can check in with our body to see if we need more calories. Right. And if it's, you know, for not eating ice cream for dinner, you know, we can say, okay, if I'm still hungry, you know, let's, let's get the caloric needs met. And, but also by asking that question, you know, what I need as compared to what I want, we can start to uncover what might be driving that hedonic hunger, if it's eating in the absence of hunger. So we might be, you know, might recognize, oh, you know, I'm bored or I'm lonely or I'm frustrated. And then we can actually kind of meet those needs. So we can ask ourselves, well, how do I meet this need? Because feeding our want, eating food is generally more of a distraction than, you know, it's not going to make whatever caused our frustration go away. So we can actually direct that energy toward, toward finding out what we need and then meeting those needs as compared to just indulging that want, that scratching, that itch.

Mike Carruthers (22:08)

Help me understand this idea of comfort eating. Comfort food that people eat to soothe something, is that a real thing or is that just an excuse to eat more?

Dr. Jud Brewer (22:23)

It's absolutely a real thing and an excuse to eat more. So when we've associated mood with food, that's, you know, it's, it's a real thing. And there's fair amount of research showing all the different ways that we associate the two.

Mike Carruthers (22:39)

Well, it does seem that you have to learn how to pay attention, like to, to really be present with the food you're eating.

Dr. Jud Brewer (22:47)

Well, the good news is we can learn. In fact, I had a patient in my clinic a couple of years ago. She used to eat a whole bag of potato chips every night. And this wasn't a snack size. This is one, a large bag of potato chips. So I asked her to just do a simple experiment which to pay attention as she ate and ask herself, how many chips is enough? Can you guess how many she stopped at?

Mike Carruthers (23:13)

25.

Dr. Jud Brewer (23:15)

Two. What, two potato chips? Yes, she found that two. She hit her, you know, her salt, it was probably the salt that, probably that, that ended it for her where she's like, okay, I've had enough. I scratched that itch. You know, she could enjoy the two potato chips, but beyond that, that itch had been scratched and she just didn't feel great after eating them because she wasn't hungry. This was at night after she'd already had dinner. And this was just an association that she'd been making and she'd been trying forever to stop, but it was simply paying attention to her body and her body, telling her everything that she needed to know. I think of it this way, that our wise, our bodies are much wiser than our brains and they're much stronger. So our feeling body is much stronger than our thinking brain. That's where we form habits. That's where we, you know, we act on our urges and at the same time we can also listen to our bodies and see when we've had enough and they'll tell us everything we need to know.

Mike Carruthers (24:20)

Tell me a little bit about this app that you created to help people with this whole issue.

Dr. Jud Brewer (24:25)

Yes, we created an app called Eat Right Now. It's actually now a CDC recognized diabetes prevention program based on helping people bring awareness to their eating habits and bringing awareness in to help them change as compared to using willpower.

Mike Carruthers (24:42)

And again, the app is called Eat Right now and it's available wherever you get your apps. I've been speaking with Dr. Jud Brewer. He is a professor at Brown University School of Public Health and he is author of the book the Hunger why We Eat When We're Not Hungry and How to Stop. There is a link to that book in the show notes and I'll put the app name in the show notes too, in case you're driving and can't write it down. Thank you, doctor.

Dr. Jud Brewer (25:10)

My pleasure.

Kit Yates (25:12)

My day kicks off with a refreshing

Mike Carruthers (25:13)

Celsius energy drink, then straight to the gym, pre K pickup back home to meal prep. Time for my fire station shift. One more Celsius. Gotta keep the lights on when the three alarm hits. I'm ready. Celsius Lift Fitness.

Kit Yates (25:27)

Go grab a cold refreshing Celsius at

Mike Carruthers (25:29)

your local retailer or locate now@celsius.com

Dr. Jud Brewer (25:34)

we heard you.

Kit Yates (25:35)

Nine years of bring back the snack

Mike Carruthers (25:37)

wrap and you've won. But maybe you should have asked for more.

Kit Yates (25:41)

Say hello to the hot honey snack wrap.

Mike Carruthers (25:44)

Now you've really won. Go to McDonald's and get it while you can. You make predictions all the time. You predict what's going to happen today, how long it's going to take to get from here to there. You predict how much money you're going to spend when you go somewhere. You're constantly making predictions. In a sense, when you buy a lottery ticket, you're predicting the winning numbers. Most of us aren't very good at that, but that's what it is, it's a prediction. Some things, we're pretty good at predicting, other things, not so much. However, you can get better at predicting your future if you understand a few principles. That's according to Kit Yates. He is a Senior Lecturer of Mathematical Science in the uk. He's been a guest here before and his latest book is called How To Expect the the Science Of Making Predictions and the Art Of Knowing When Not To. Hi, Kit. Welcome back to Something youg Should Know.

Kit Yates (26:44)

Hi, Mike, thanks for having me.

Mike Carruthers (26:46)

So you say there, there's some basic principles that you can apply to making predictions about the future that can improve the. The accuracy. But there are plenty of things where you can't do that. I mean, you can't predict. I don't care what principles there are, you can't predict what the winning lottery numbers are going to be. But you say you can make some predictions about the lottery, so let's start with that.

Kit Yates (27:12)

So, yeah, with the lottery, for example, it's a random process. In the UK, the lottery used to be picking 6 balls from 49 and you had a 1 in 14 million chance of winning. So not very good odds. But there are some things that we can do, maybe not to improve our chances of winning, but if we do win, to make sure that we make the most of that, that we take the maximum jackpot and we can do that by exploiting other people's perception of randomness. So we think of randomness as being well spaced out. When we pick our lottery numbers, we tend to pick maybe one from each row on the card and space them out really nicely. But actually, in half of all lottery draws from that UK lottery, you would see two consecutive numbers coming up in the draw. But we don't think of that as random. We think randomness is really well spaced. And actually we're also subject to biases about choosing our numbers from people's birthdays. So, for example, the numbers 1 to 31 get chosen a lot more often. So we can exploit these sort of biases in other people's perception of randomness by choosing an unlikely set of numbers, which says if we do win, then that we don't share the jackpot. We've had draws in the UK where 253 people have shared the jackpot, despite the fact it's a 1 in 14 million chance of matching the numbers. Because people's way of choosing so called random numbers is not really very random. So many people choose the same numbers. So randomness and maths can help us to try and at least maximize our winnings if we do win the lottery.

Mike Carruthers (28:46)

Well, it's interesting what you said about randomness, because I remember talking to someone else on the podcast about that, that people don't understand that randomness isn't always as random as you think it is.

Kit Yates (29:01)

The other thing about understanding randomness, which I think is really important, is that coincidences are actually surprisingly likely. And I'll go back to the lottery with that one. Right. So it's incredibly unlikely for any one person to win the lottery, but because so many people play the lottery each week, someone wins almost every week. And it comes back to this idea of coincidences. We think when a coincidence happens that it's an incredibly unlikely event. And we often jump to conclusions on the back of those coincidences occurring. And actually there's this idea, this law of truly large numbers, which says given enough opportunities, even incredibly unlikely things can occur. So one of the other lessons that I draw about decision making or about understanding what's happening to us is that even unlikely events can and do happen. That we should start to expect coincidences to occur and not to draw, not to jump to conclusions about these being messages from the other side or, you know, inferring spurious causation on things which may just be explained by random chance.

Mike Carruthers (30:08)

When we do make predictions, what do we typically use to make them? I mean, when I make a prediction about how the day's gonna go, it just feels like that's just my gut thinking. It's just like based on what I've happened, what's happened in the past, and what I think is likely to happen, my gut tells me this is gonna happen. And that's what I go on.

Kit Yates (30:32)

Yeah. And that's not an unreasonable way to predict the future in many instances. So, you know, if you know you're going to work, then for sure you can sort of see how your day might pan out. You have a look at your diary and see what's gonna happen to some degree. Right. But there are other occurrences where assuming that things are going to continue in the same way that they do isn't a particularly good assumption. So, for example, when we were trying to roll out the vaccines at the start of the middle of the pandemic, if you like. When we were trying to get vaccines out to people, it started off really slowly because we hadn't got the infrastructure set up right. And so lots of news agencies were saying, well, at this rate we're not going to have vaccinated the whole of the American population for 10 years. And that's an inherent assumption, which is based on linearity, that things will continue to change the way that they're currently changing. And of course, actually what happened is that we ramped up vaccine delivery capacity hugely and so we didn't continue to give vaccines at that rate. And actually the whole of the US adult population was vaccinated within six months of the first vaccines being given out, or at least everyone was offered the vaccine within six months of those being given out. So there are some situations where making that basic assumption of what's happened at the moment or the current rate of what something a phenomena is changing at is not a good assumption into the future. And we need to be aware of when those phenomena, like things like exponential growth can come into play.

Mike Carruthers (32:02)

So what I thought was interesting is that you say one of the reasons that humans aren't very good at predicting the future in a lot of cases is we have these different biases and that skews our perception of what's going to happen, like the linearity bias and the other ones. So let's talk about those.

Kit Yates (32:21)

There's a number of sort of fun questions that we can ask people to try and unpick this, what's called linearity bias. So for example, I might ask you, Laura's a sprinter, her best time to run 100 meters is 13 seconds. How long will it take her to run a kilometer? And so I can work it through with you. A kilometer is 10 times as long as 100 meters. So it should take her 10 times as long. That's what the linear reasoning suggests. So it should take her 130 seconds. Now, the problem with that, that's 2 minutes and 10 seconds. The problem with that is that the world record time for the kilometer is 2 minutes and 11 seconds. So actually it doesn't make sense because no one can expect to keep their best 100 meter pace up for 10 times as long for a whole kilometre. And that is the essence of linearity bias. We're sort of taking these problems that we've been drilled with at school and applying them to the real world where it might not be appropriate. There's another one that I asked ChatGPT, the AI chatbot was about towels. So the question Asked was it takes three towels, three, three hours to dry on the line, how long does it take nine towels to dry? And of course you can immediately see through the error in what ChatGPT is about to do. They said, well, you know, if it takes three hours for three towels to dry, it should take nine, nine hours for nine tiles to dry on the line. And of course it provided your washing line is big enough, you can dry tiles in parallel. So it shouldn't take any longer for 9 tiles to dry. So then it takes 3 tiles to drive. But ChatGPT has even this AI chatbot has got this linearity assumption drilled into it. And I think by assuming that processes are linear when in fact they may well not be linear, they may do things which confound our expectations, like having negative feedback loops becoming self fulfilling prophecies, self defeating prophecies. Then we make bad predictions about the future.

Mike Carruthers (34:06)

Well that's interesting. Talk about the feedback loops that you mentioned and this self fulfilling prophecy, what that's all about.

Kit Yates (34:14)

Well, so there's two, there's this, there's a positive feedback loop can lead to a self fulfilling prophecy. So that's a prediction that someone makes which makes itself come true. So a nice example of that is the placebo effect in medicine. In medicine we have to control for the placebo effect because what effectively happens is when people get a treatment, even if that treatment has no sort of active chemical in it to actually treat the disease that's being treated, people start to feel better simply because they're being treated. It's often called the lie that makes itself come true. So we have to make sure in medical trials that we have two arms, one that are given a placebo, so a sugar pill if you like, and the other that are given the active drug because just being treated makes people feel better. So we could draw the wrong conclusions if we see people getting better, even if that drug doesn't actually have any significant effect, that's an example of a self fulfilling prophecy. But we also have self defeating prophecies. So for example, these are predictions that make themselves come false, if you like, like. So at the start of the pandemic we had modeling predictions about what was going to happen over the next few weeks. In the UK we had a prediction from Imperial College which suggested that 250,000 people would die if we carried on with the current measures that we were taking. Now of course no government faced with that prediction would do nothing in the face of it. And so that terrible prediction was actually averted and actually That's a reason for many skeptics of lockdowns and other pandemic measures to say, well, the modelers were all wrong. The modelers made mistakes because their predictions didn't come true. And of course the reason they didn't come true is because of this negative feedback loop. It was a self defeating prophecy. It acted to defeat itself and the prediction itself meant that it didn't come true.

Mike Carruthers (36:04)

So it seems that the assumptions that we make and just the way we think in a not so scientific y way mess up our predictions. And I think, you know, a good example, I mentioned it before, a good example is understanding randomness. And people don't really understand randomness. They confuse randomness with, you know, variety. And I remember hearing a while ago, a long time ago, about this problem of this perception of randomness as it pertained to how people listen to music.

Kit Yates (36:38)

Exactly. So this, this was the, at least the example I know of was the, was the ipod shuffle, right? Even before streaming services, you know, you could put 10,000 of your favorite songs on there and just get it to play randomly. That's all it did, basically, was pick these songs uniformly at random with replacement. So, you know, you could pick the same song twice. And of course, when even two songs by the same band came up, people said, you know, this, this isn't, this isn't random. And there was a journalist who had, who had access to Steve Jobs, he was interviewing him and he said, look, I had these two steely dance songs come up the other day. This can't possibly be random. And Jobs got an engineer on the phone and he said, you know, can you just check that, you know, the algorithm we're running in the code actually is genuinely picking these songs at random. And the engineer said, yeah, yeah, absolutely. And Jobs reassured the journalist, nevertheless, the journalist wrote this article and hundreds of people wrote into him saying, yeah, I've had that as well. I've had two Oasis songs played back to back or whatever. And so, yeah, Jobs decided that he was going to implement something in the algorithm which meant you couldn't play the same song or a song by the same band back to back. And he said, yeah, we're making it less random to make it feel more random. And it's, it's like this coincidence in the lottery where we don't expect two consecutive numbers to come up. We don't expect two songs by the same band to come up. We don't think that that's random. So we're not very good. When we do see a Genuinely random pattern of picking. We're too good, if you like, at picking out patterns in random data and thinking that there's causality where there isn't any.

Mike Carruthers (38:04)

Where else do we do this? What other kinds of biases do we have that skew our thinking here?

Kit Yates (38:10)

So we see it all over the place, right? We see it when we pick up a face, the man in the moon or the red face of Mars. We see it when. It's quite fun when you're cloud spotting and you try and pretend what the shapes in the clouds are. I do that with my kids all the time. But we also do it, the sort of famous examples of people doing it, looking at cases of cancer in particular cities. So they'll look at a city map and they'll plot cases of, in this example, childhood leukemia, for example, and they'll find clusters, clusters which may just have come up because the data is random. And we do see clustering in random data. But then they. In a particular example in Omaha, they overlaid power line grids on top of this map. And they saw that in one of these clusters there was a group of power lines or substation nearby. And they went all the way to the government and said, look, this. These power lines are causing our kids to have cancer, despite the fact that there were a number of other clusters which weren't near power lines, and despite the fact that there is no physical evidence or even scientific evidence using trials to suggest that power lines cause cancer. And so, you know, it can confound us when we see these clusters. We jump to conclusions about causation, where, in fact, those cancer clusters may well just have been randomly distributed around.

Mike Carruthers (39:29)

Well, it would seem that the way you would test that would be to look at places that have power lines and no cancer and then say, well, see, that's. Hello.

Kit Yates (39:38)

Yeah, exactly. Exactly. But especially for people who are emotionally involved in. In these situations, it's hard to reason like that. But, yeah, you're absolutely right. There were, you know, there were places both in other cities and indeed in the same city where there were clusters, but there were no power lines. And, yeah, obviously you can put that point to people, but it's really hard to shake people when they think they've found a causal connection between something which they're particularly emotionally invested in.

Mike Carruthers (40:08)

We are really handicapped by our own thinking in a lot of ways that we don't. And then we're doubly handicapped because we don't realize the handicap.

Kit Yates (40:17)

Yeah, exactly. It's sort of not knowing what we don't know. And I'm not necessarily giving people ways in which they can always predict the future with 100% certainty. But what I am trying to do is at least give us that first part where we can say, at least now I know the places to look for this. At least I know now that coincidences can be surprisingly likely or that, you know, both. With random data, I expect both clusters, but also large areas where there are. Where there are no cases of cancer, for example. And it doesn't mean that there's some sort of healing well near those places where there are no cancer cases. It just means that those are places where there happen not to be dots, but those are the sorts of things we expect with genuinely random patterns. Again, we expect randomness to be quite evenly spaced, and when it isn't, that can confound our expectations.

Mike Carruthers (41:06)

So this whole idea of coincidences, people either believe in coincidences or they'll say things like, there's no such thing as a coincidence, that things happen for a reason. And it all gets mixed up in this soup that, you know, people don't know what to believe. But you're saying that coincidences happen a lot?

Kit Yates (41:27)

Yeah, absolutely. I've got a lovely story about a coincidence that happened to me when I went on holiday, I met up with my brother. He arrived a couple of days after me. We were going to France, we're in the south of France. And he arrived and he put his book down on the side and had a hug and said hi. I looked at his book and sticking out of his book is a book by Paul Auster, New York Trilogies. And sticking out of his book, he had a bookmark which had P. Aust on it. And I said to him, why have you started printing out bookmarks with the name of the author on? Isn't that a bit geeky? And he looked at me like, what? He said, that's just my train ticket. And I picked it out of the book and it was his train ticket. And I was like, what is this? But I realized that the train station that he'd come through on the way to southern France was Paris Austerlitz, which, when you abbreviate it, has the same abbreviation as Paul Auster. It said P. Aust on it. And so I jumped, you know, this is just a freak coincidence. But I jumped to this conclusion thinking he was doing this weird thing of printing out bookmarks, when actually it was just random chance, I think, like the fact that I tell that story because it's a really weird coincidence, right? It's not one that. It's not one from the classic stable of coincidences. But that's the point, right? That there are all sorts of weird things which would make us sit up and take notice of them. Weird coincidences which can happen. All sorts of opportunities for these strange and unusual things to happen, and all sorts of, you know, huge amounts of time over the course of our lifetime for these coincidences to happen. So what I don't want to do is steal the magic of coincidences away from people because I think they're really fun and it's great to tell those story stories. But for me, the magic of coincidences comes in finding out how that coincidence happened and how I. How we spotted the coincidence, how we even spotted it, because there are obviously hundreds of these sorts of events happening all the time that we. That we don't get to see. You often hear stories of people who are neighbors and they neither knew the other one was going on holiday, and they end up sitting on the opposite side of the restaurant to each other and spotting each other. But there must be similarly examples of neighbors who sit in the same restaurant but are seated opposite each other and never see each other. And, you know, the fact that we spot these coincidences, that for me, is the real magic of. Of seeing these unusual events. And I guess it. I'm trying to say that we shouldn't jump to conclusions just when we see an unusual event occurring.

Mike Carruthers (43:47)

There is something about coincidences, though, that. That just. It's kind of spooky. It's kind of like weird. Like, what are the odds? I mean, this is. That there must be a reason for it. I think that's what the human brain does. It tries to make sense of something where there really isn't anything other than you just happen to be sitting in the same restaurant at the same time.

Kit Yates (44:08)

Yeah, that's right. And so for the very first chapter of the book, I go and see a psychic and try to understand how someone with no seeming predictive ability, no scientific tools, can give off the appearance of being able to predict. And one of the things that she said to me, you know, have you ever had that experience, Kit, where you, you know, you're thinking of someone and then they call you? And I said, yeah, that happens to me quite often. And she said, well, that's because you've got, you know, psychic abilities. You're, you know, you're psychically present. And I was very polite and said, okay, that's really interesting. I didn't say, no, of course, that's not the case. But. But of course that happens to everyone because, you know, we're often thinking about people and they're thinking about us. And then it happens that, you know, maybe you haven't spoken to a friend for a while and you think, oh, I should get in touch with them and they're thinking the same thing and they ring you. It's a coincidence, but, you know, it's one of the most common type of coincidences. It happens to almost everyone. But it doesn't mean that I've got psychic ability just because that has happened. And a lot of the things that the psychic was trying to tell me meant that, you know, these were psychic or mysterious things were actually just examples of coincidences happening.

Mike Carruthers (45:19)

Well, it does seem too that people kind of mix up in, in or put under the same umbrella, coincidences and deja vu. And, you know, it all kind of is all kind of mystified and mysterious and, and. And nobody. It's. It's almost like we don't really want to know. We don't. You know, it's like it's just so magical and if you pull the curtain back and explain it, you ruin it.

Kit Yates (45:45)

Yeah, I think that's sad. And for me, that's the thing about the coincidences is that I don't want to ruin it for people, but for me, there's a different way of finding the magic in it.

Mike Carruthers (45:53)

Well, when people talk about coincidences, very often they put the word lucky in front of the word coincidence. That there is this element of luck to it, that coincidences are a little bit mystical, a little bit magical. Maybe they happen for a reason. But as you point out, even if they do happen for a reason, they happen a lot. They're a lot more frequent than I think people realize. Kit Yates has been my guest. He is a Senior Lecturer of Mathematical Science in the UK and author of the book how to Expect the the Science of Making Predictions and the Art of Knowing When Not To. There's a link to that book in the show notes. I'll also put a link in the show notes to Kit's other appearance here, back on episode 362, where he was talking about the math of life and death, which was really interesting if you haven't heard it. Thanks for being here, Kit.

Kit Yates (46:46)

Thanks, Mike. Thanks. I really appreciate that.

Mike Carruthers (46:52)

Back in 2008, an Oxford University researcher compiled a list of the 10 most overused and annoying and despised words and phrases that we hear every day in conversation. And what's so interesting is in the what is it like 16 years since then? Not much has been done to get rid of these because you still hear them all the time. Number 10, it's not rocket science. Number nine is 24. Seven, eight. Shouldn't have. When you're trying to say shouldn't have, it's a nightmare is number seven. Number six is absolutely. Next is, with all due respect, the fourth is at this moment in time, the third most despised phrase. I personally next is fairly unique. And the number one most despised phrase at the end of the day. So check back in about what, another 16 years and we'll see if these phrases are still in popular use in the English language. And that is something you should know. You know, we have a lot of reviews on Apple podcasts, thousands of them. A lot of reviews on Spotify and we're insatiable. We just never get enough ratings and reviews help this podcast. It's a good way to show your support. It only takes a minute. So please, please leave a rating and review. Preferably five stars. I'm Micah Ruthers. Thanks for listening today to something you should know. I know you like interesting and thought provoking conversations and ideas because you listen to something you should know. So let me recommend another podcast I know you will enjoy. It's the Jordan Harbinger Show. Jordan has a real talent for getting his guests to share stories and offer thought process provoking insights. Over the years I've sent a lot of people to listen and I get feedback from people who are so glad I introduced them to the Jordan Harbinger Show. Recently. He discussed Scientology and the children who are raised in that organization. It's a fascinating conversation and he talked with Dr. Rhonda Patrick about how to protect your mind and body from the modern world. And it's tougher than you think. I've gotten to know Jordan pretty well. We talk frequently and I tell you, he is a very smart, insightful guy who does a hell of a podcast. Check out the Jordan Harbinger show on Apple Podcasts, Spotify or wherever you listen to podcasts.