All The People You Don't Know

Do your friends actually like you? Does an acquaintance think you’re closer than you are? This week, Hannah Fry and Michael Stevens explore the surprising psychology of friendship, from familiar strangers and para-social relationships to the unsettling discovery that nearly half of friendships may not be mutual. Why are we so bad at judging who considers us a friend? Why do strangers often have a bigger impact on our lives than we realise? And why do your friends almost certainly have more friends than you do? Along the way, they uncover the science of social networks, loneliness, influence, popularity, and the famous friendship paradox, revealing how the hidden connections around us shape our health, happiness, and behaviour. A View From A Bridge - https://www.instagram.com/aview.fromabridge Letters Anonymous - https://www.lettersanonymous.com Are You Friends', Friend paper - https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0151588&type=printable ------------------- For more information about Cancer Research UK, their research, breakthroughs and how you can support them, visit ⁠⁠https://cancerresearchuk.org/restisscience ⁠⁠Cancer Research UK is a registered charity in England and Wales (1089464), Scotland (SC041666), the Isle of Man (1103) and Jersey (247). A company limited by guarantee. Registered company in England and Wales (4325234) and the Isle of Man (5713F). Registered address: 2 Redman Place, London, E20 1JQ. ------------------- Find The Rest Is Science all over the internet by ⁠⁠clicking here.⁠⁠ ------------------- Video Producer: Adam Thornton + Oli Oakley + Jack MeekAnimator: Sam BensonVideo & Social: Bex TyrrellAssistant Producer: Lucy LipscombeProducer: Simona RataSenior Producer: Lauren Armstrong-CarterHead Of Digital: Samuel OakleyExec Producer: Neil Fearn Learn more about your ad choices. Visit podcastchoices.com/adchoices

• 0:01Speaker 00

  Welcome to The Rest of Science. I'm Hannah Fry.

• 0:03Speaker 01

  And I am Michael Stevens. Hannah, you and I have some friends, I'm sure. You've got friends?

• 0:09Speaker 00

  Some.

• 0:09Speaker 01

  Some? Yeah. I think I do, too. Are the people out there listening to us our friends? What is a friend?

• 0:15Speaker 00

  Sort of, yeah.

• 0:16Speaker 01

  I want to talk about a lot of things today, including a 2015 study that looked at friendships, specifically whether you are your friend's friend.

• 0:29Speaker 01

  Yeah.

• 0:30Speaker 00

  Is it reciprocal?

• 0:31Speaker 01

  This question had not been asked before, apparently. There'd been a lot of studies and data sets about friends and social networks, but none looked at the reciprocity of them. Sure, you consider Jim your friend, but does Jim call you a friend when he thinks he's anonymously asked? And the results were not pleasant.

• 0:54Speaker 00

  Oh, Ben, okay.

• 0:57Speaker 01

  Yes. As it turns out, we, as a species, are really bad at judging whether someone is a mutual friend or not. And that's kind of scary.

• 1:06Speaker 00

  I did see something, actually, yesterday, in fact, my partner was on Reddit, and there was this Reddit thread, and they were talking about me, whatever. And then someone on the Reddit thread says, "Oh, I'm friends with her in real life." Obviously Reddit, so you don't know who anyone is.

• 1:26Speaker 01

  Sure.

• 1:27Speaker 00

  And then the conversation continued. And then they said, "Oh, yeah, I go to parties with her." And that immediately raised a big old red flag for me, because I haven't been to a party since about 2003. So if we are friends in real life, that's something that's got more longevity in it than I would consider. I think that that is a non-reciprocated friendship.

• 1:51Speaker 01

  That is a perfect example of a non-reciprocated friendship or a unilateral friendship. It's also probably an example of a influencer, where you are the influencer, and they see themselves as your friend, but maybe you don't see it the other way.

• 2:10Speaker 00

  This is harsh. Whoever that person is, I'm sorry. Call me. Call me. I love you.

• 2:15Speaker 01

  Yeah, give Hannah a call. We really appreciate you giving us a great anecdotal piece of evidence for this episode. And we're going to talk about you the whole time.

• 2:23Speaker 00

  If you've got my number, which I doubt it.

• 2:27Speaker 01

  And we're also going to talk about many other things, including the friendship paradox, which is the established scientific fact that your friends have more friends than you do. And not only that, but your friends have more money than you do and are healthier than you are. All of that after the break.

• 2:51Speaker 01

  This episode is brought to you by Cancer Research UK.

• 2:54Speaker 00

  Scientists have found that cancer risks usually increase with age and size, but some species defy the odds.

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  So by exploring the unexpected, Cancer Research UK scientists are uncovering new ways to tackle over 200 types of cancer. Their work has helped to double survival in the UK over the last 50 years and continues to save and improve lives around the world.

• 3:49Speaker 01

  For more information about Cancer Research UK, their research and breakthroughs, and how you can support them, visit cancerresearchuk.org/the rest is science.

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• 4:33Speaker 03

  This episode is brought to you by Michelob Ultra. Good times mean competitions between you and your friends, like seeing who can throw some pigskin the farthest or rush the field the fastest. Winner gets an Ultra. Because it's not just a superior-like beer, it's also giving fans superior access to their favorite sporting events. Superior is worth playing for. Visit michelobultra.com/superioraccess to enter. Enjoy responsibly. Copyright 2026 Anheuser-Busch InBev Michelob Ultra Beer St. Louis, Missouri.

• 5:07Speaker 01

  All right. So I want to start our discussion of friendships by talking about strangers. That's a good place to start. It's like the opposite place to be. As it turns out, there are a lot of different kinds of strangers. And ever since the 70s, researchers have tried to create a taxonomy of strangerhood. First of all, there are complete strangers. These are people that you would not recognize. You've never met them. You don't know anything about them. But then there's this really rich group of what I call incomplete strangers. And my favorite con was identified by Stanley Milgram, of all people, the guy who did the

• 5:47Speaker 01

  torture experiments. He said, "You know, we've got to talk about this kind of relationship humans have that's not a stranger and it's not an intimate friend. It's not an acquaintance either. It's a familiar stranger."

• 6:02Speaker 00

  What does that mean?

• 6:04Speaker 01

  So here's the definition of a familiar stranger. It is an individual you repeatedly observe, yet do not directly interact with. That comes from Paulson Goodman out of Berkeley. Right.

• 6:15Speaker 00

  So it's like when you're on holiday, there's the same family at the buffet every morning, and you spot them, and you see them at the pool, and you're like spy on them, but you've never spoken to them.

• 6:25Speaker 01

  Exactly. And in fact, there's a mutually understood behavior pattern between both of those groups. They see you, too, at the buffet. And you both agree to ignore each other. And that's totally healthy. It's very normal. There's no hostility involved there at all. You have agreed, we are familiar strangers. I recognize you, but I'm not going to say anything to you ever. This can be in your day-to-day life. It can be the person you see at the same train station every morning. And if they weren't there, you would notice. But you both have this agreement that you're not going to talk to each other. One of my

• 7:05Speaker 01

  favorite descriptions of these kinds of people is from a Clickhole article from 2020. I'm going to send it to you because I also just love the picture of the guy. Hopefully, we can show it on screen. So first of all, there's a picture of a guy who's bald with a goatee and big eyebrows, and he's got a green army vest over a green t-shirt. And the headline says, "Heartbreaking." This guy has no idea that he's so strange and memorable-looking that everyone from his flight is using him as a landmark to figure out which baggage claim area is theirs.

• 7:39Speaker 00

  Amazing, amazing.

• 7:40Speaker 01

  I love it because we've all met these people. They were on your flight because there was something remarkable about their appearance that means you remember them. And later on, you go, "Oh, there's that guy with the mohawk or the weird ears. This must be our baggage claim carousel, because I know he was on our flight." And everyone has that same experience. They're all going, "But here's the thing. Sometimes you're that person."

• 8:07Speaker 00

  I fear, I genuinely fear, being almost six foot tall and having red hair.

• 8:12Speaker 01

  Yep.

• 8:13Speaker 00

  I genuinely fear that for almost all of my life, I have been that person. And now I wear really bright colors because I don't really care anymore. So I think I have become that person all the more.

• 8:23Speaker 01

  That's good. And embracing it and meditating on that fact is, I think, good for the soul. It's actually called the epiphany of the familiar stranger, which is the realization that you are someone's familiar stranger. Someone you have never met, whose name you don't know, recognizes you and goes, "Oh, there's that guy."

• 8:42Speaker 00

  And that's true for all of us.

• 8:44Speaker 01

  It's true for all of us. It's related to the dictionary of obscure sorrows coinage of the word "Saunder," which is the realization that all these people, those people on that train over there that you're not even on, they have rich, deep lives, full of concerns and ambitions, just as strongly as you yourself have them, that we're all individuals. And so to be someone's familiar stranger is a cool thing to think. I mean, I walk to work every day, and I think there must be people who were on their commute, driving on the roads, that see me crossing the street every other day or so, and they go, "Oh, there's that guy." I mean, I'm not six foot tall with red hair, but I am like a bald guy with a big beard and big glasses. And they probably go, "Oh, there's that guy."

• 9:30Speaker 00

  I mean, you're cheating slightly because you're also V-Sauce. So I think I probably noticed if V-Sauce was on my commute.

• 9:38Speaker 01

  Yeah, okay. If they're familiar with V-Sauce, then that's a whole other thing, where they don't interact with me. They don't just observe me. They do know more facts about me. Their observation comes in a richer form through videos. They know of me, but I don't know of them. Anyway, the familiar stranger effect can be changed quite suddenly.

• 10:03Speaker 01

  For example, obviously, in the case of an emergency, we suddenly will interact with familiar strangers and feel a bond to them. Also, if we find ourselves and our familiar strangers outside of our routine. So if I ran into the the person that I always see at the pet food store, but have never spoken to, never interacted with, if I ran into them in Rome, I'd be like, oh, my gosh, you you live in Colorado like and and they would recognize me, too. And we would suddenly feel so much closer. We would ask each other our names. What do you do? And it would it would it would change the relationship.

• 10:42Speaker 01

  But while we're in our routine, we remain familiar strangers with a mutual agreement to ignore each other.

• 10:51Speaker 00

  I remember a story. It was in in 2016. And there was a someone who would order pizza basically every single night. We'll just come in, get his pizza, kind of had a regular order. And, you know, the staff didn't hang out with him, but they knew who he was and they knew where he lived, right? Because he had this had this this pizza ordered. Anyway, one one night, the the store manager was looking through the orders and and was like, hang on a second. This guy hasn't placed an order for 11 days. There's something really strange going on here. So they decided to send a delivery driver around to the house to just check if the thing was all right. And they found basically he'd had a he'd had a stroke and was because he was living on his own.

• 11:34Speaker 00

  He'd had a stroke and he was, you know, genuinely in mortal danger. And these staff, just because he was a familiar stranger, you know, despite never having sort of been emotionally connected to him before, managed to save his life. And that gorgeous story, you sort of care for your familiar strangers.

• 11:52Speaker 01

  There are a lot of stories like that, and I want to revisit that. Because familiar strangers might not seem as important as our intimate connections and our and our close friends and family. And yet they play a pivotal role in our lives. There's, by the way, I I forgot to say, there's a name for those remarkable familiar strangers that we all kind of recognize and go, oh, there's that guy. Sometimes it's just, oh, there's that pink car. Like, it's always, it's always, you know, coming in around 9:00 AM, parking in one of those spots. They're called by by psychology researchers sociometric stars.

• 12:30Speaker 00

  Okay.

• 12:31Speaker 01

  They're a special class or kind of familiar stranger who stand out in a community or group and are recognized by an extremely high percentage of people.

• 12:39Speaker 00

  So sociometric is like by the metric of social status?

• 12:43Speaker 01

  That's right. Yeah, yeah, they are. They are recognized by and sort of familiar to their social group. Even even those that they don't interact with, they're sociometric stars. So, Clickhole, you have described as sociometric star, kind of a weird looking dude.

• 13:03Speaker 00

  It's a much nicer thing. All gingers of the world, I think, can call themselves that.

• 13:07Speaker 01

  Oh, for sure, for sure. So so other people recognize them and make a mental note of it consciously or not. And then agree to ignore it and not like bring it up or say, oh, my gosh, your hair is red. I can't help but notice you. What's your name? I mean, some people do that. But this this pervasive ignoring with without hostility has another cool name. It's called civic inattention. There's an agreement we have that when I'm on the train, I'm going to pretend like I don't even realize you're there. I'm not listening to your conversation, even though I am. I pretend to be inattentive because that's the civic thing to do. There's a a different kind of stranger besides the familiar stranger that's a little bit closer.

• 13:51Speaker 01

  And and this type of relationship was first described by Karen L. Fingerman. Great name, by the way.

• 13:57Speaker 00

  Great name.

• 13:59Speaker 01

  We've got a few great names today. So she described what she called the consequential stranger. The consequential stranger is someone that you don't mutually ignore, but you're not intimate. One of the key defining differences between your intimate friends and the consequential consequential stranger is that there's basically no obligation. Okay, this might be someone like the person at the hardware store or the grocery store. You might know their name. You tell them about your day when you check out. They work there. But like you would never invite them to your birthday party.

• 14:33Speaker 00

  You're not going for a beer with them?

• 14:35Speaker 01

  That's right. You would never give them a ride to the airport. And there's no expectation that that kind of obligation would ever come up in your relationship. So sometimes we call them acquaintances. But there are obviously different degrees of acquaintanceship. One one kind that psychologists talk about a lot is the nodding relationship, which is a very fringe one where you'll just kind of nod at each other. You know, often, often it's a coworker that's in a completely different department, or they share a building but work for a different company. And you recognize them and you gotta you gotta do something. So you nod, but you don't even talk.

• 15:10Speaker 00

  The country roads version of that is the one finger wave. Hands still on the steering wheel, one finger wave.

• 15:16Speaker 01

  One finger wave. They do that out here where I am, by the way. It's like a whole thing. And my wife does most of the driving out here because I'm not used to driving on the right hand side of the car. But she always like talks about, oh, man, I need to get better at doing the wave because she always misses it. Because she's just not used to doing it. Where am I, by the way, you might be wondering? I am off the grid in in New Zealand, visiting. I've told Hannah all about this. I don't want to dox myself. But basically, I married a woman who has a lot of family in a certain location, and I am there right now. That sounds so mysterious. I don't mean it to sound mysterious.

• 15:51Speaker 00

  No, it's great. You got you got your wife outside turning a hand crank just to give you power.

• 15:57Speaker 01

  No, I don't. I don't. The the electrical power all comes from the sun. We've got solar panels on the roof. And so I am, it's I'm nervous. It was sunny yesterday, but it's cloudy today. So I'm I might be using up all the power just to do this.

• 16:12Speaker 00

  It was worth it.

• 16:12Speaker 01

  But yeah, that's what the fire is for. The fire gives you the light you need. It also gives you warmth. It's your clothes dryer. It's how you cook.

• 16:19Speaker 00

  And it makes sense that you are currently in winter.

• 16:22Speaker 01

  Yes, I am currently in winter, whereas you are currently in summer.

• 16:25Speaker 00

  Yeah, I I would swap, frankly. This is disgustingly hot here.

• 16:30Speaker 01

  I I I do not envy you. I am so glad. I love escaping the northern hemisphere summer for this winter. Fingerman also fingered a different kind of relationship.

• 16:42Speaker 00

  It's becoming a very finger themed section.

• 16:44Speaker 01

  She she's the one who coined the term fringe ship.

• 16:49Speaker 00

  Okay.

• 16:50Speaker 01

  Not a friendship, but a fringe ship.

• 16:53Speaker 00

  So is this like somewhere between your intimate friends and your, what did you call them? Consequential strangers?

• 17:00Speaker 01

  Yeah, consequential strangers are called consequential because, as it turns out, after decades of study, it's really been established that the majority of what events change our lives come from these strangers. Obviously, my close family affects my life really directly. But when it comes to things like job opportunities, when it comes to things like finding flats to rent, finding a dog or a cat to adopt, it's not usually my mother, who happens to know that there's an opening at some company. It's my neighbor's brother who had just visited last weekend, right?

• 17:42Speaker 01

  It's it's, oh, my daughter's teacher has a cold college friend who's got a bunch of kittens.

• 17:49Speaker 00

  Is that is that by virtue of just the fact that there's so many more of them? I mean, I'm sort of, if you're thinking of like an onion here, right? Like, you're in the center. Your immediate friends and family are surrounding you. And as you go sort of further out through friendship, consequential strangers, familiar strangers, and out to complete strangers, it's like the number just gets progressively larger and larger and larger.

• 18:11Speaker 01

  Yeah, the number gets larger, and so the diversity increases. And it also makes sense that, you know, we would self select intimate friends that are more similar to us. But when it comes to a life changing opportunity, it's going to come from outside of our routine, which means it's going to come from someone we haven't self selected to have as a really close friend. The decision that you made to really change your life came from a consequential stranger. And as social media grows, there's yet another kind that was named by Hidnori Tomita, the intimate stranger. This is a person that we have anonymous contact with, usually through the internet, that we yet share quite intimate details with.

• 18:56Speaker 01

  And this is just a word. I don't think there's been a whole lot of research into differentiating the intimate stranger from the consequential stranger, except for the fact that the intimate stranger needs to be an anonymous, we we don't even share names. You might only know their avatar or their username. But we do know that people often feel very comfortable sharing intimate details with strangers.

• 19:24Speaker 00

  There's a sort of safety to it almost because you don't feel as though, I don't know, like the stuff that you tell them is going to come back to bite you if they're unconnected from your life. I think there's something that's a little bit freeing potentially about that.

• 19:42Speaker 01

  That's right. It's freeing. It's also freeing to know that because they don't know the people involved and they haven't heard it before, you're, you can kind of tell it fresh and you can understand yourself better by talking. It's like a therapist, except they don't even have a history. You know, it's like your first day with a therapist. You're like, okay, I can kind of like look at myself from outside because you're so outside. And there's a, there's a bit of a hump, it's been discovered when it comes to how, how easily we will share intimate details with, with strangers. They call this the stranger on the train phenomenon, by the way, the fact that people are so open with those they really don't know. But that hump is that we have this civic inattention,

• 20:26Speaker 01

  this like, we're not going to talk hump to get over. And so when researchers investigate how intimate strangers will be with them, it sounded kind of weird, but what I mean is sharing personal information.

• 20:38Speaker 00

  Emotionally intimate, yeah.

• 20:40Speaker 01

  Emotionally intimate, yeah. They find that it's really hard to get it started. It's really hard to get a stranger to share a cab with you, even if you agree to pay the whole fare. But once you get them in, they'll start telling you about their divorce. They'll start telling you about how maybe they're never going to find love. And it's, it makes them feel better, but they just needed to get in the cab in the first place. And you needed to invite them in and convince them to get in in the first place. And then all this growth can occur.

• 21:07Speaker 00

  There's a really beautiful YouTube channel that I really like, which is where they have a phone, like an old fashioned sort of corded phone set up on a bridge. And the camera starts out with a person's face just framed, they're holding the phone and that's kind of all you see. And they're telling a story that's incredibly emotionally intimate, incredibly personal about some trauma that they, that they lived through, or, you know, the thing that they dislike the most about themselves, right? It's really, really, really revealing stuff. And as they're talking, the camera slowly pans away and you realize that it's this incredibly long lens shot that the, the, the actual camera, there's,

• 21:49Speaker 00

  there's sort of, you know, nobody's really listening. This person is essentially talking out to the open water. We feel freer to reveal the most, the innermost secrets that we have, when we don't necessarily feel that we're like divulging it to someone where there'll be consequences.

• 22:10Speaker 01

  Okay. You, you gotta share that link with me because I'm trying to remember there was also like a blog that would publish letters you could write anonymously where you could apologize for something or admit something or discuss a regret that you would never say to anyone involved, but you needed to say to strangers. It wasn't post-secret. It was something else. I'm sure the commenters will know.

• 22:37Speaker 00

  This is called a view from a bridge. Let me send it to you. It's absolutely beautiful.

• 22:41Speaker 01

  Ooh, thank you.

• 22:44Speaker 00

  I have one more question actually about that idea of intimate strangers. That has to be reciprocal, right? It's not, this is a relationship between two people. It's not just someone divulging stuff about them into the ether. This intimate stranger friendship in inverted commas means the details are being shared both ways.

• 23:05Speaker 01

  I don't think it has to be actually. I think that sometimes you just need someone to listen and one can just be the anonymous listener and the other can be the divulger.

• 23:16Speaker 00

  I'm thinking about some very oversharey influencers here, basically.

• 23:20Speaker 01

  Ah, interesting. Well, yeah. So influencers, I think, can bring us into what I want to talk about next, which is the directionality of friendships and how it's not always as even as we think or would like.

• 23:34Speaker 00

  Okay. Well, that sounds like a perfect point for us to have a little break. And yeah, when we come back, we'll find out why you're not as popular as you think you are.

• 23:53Speaker 01

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• 25:59Speaker 01

  Okay, welcome back, everybody. So we've been talking about strangers and the different kinds and the different sort of surprising relationships we can have to people we don't even know. And the fact that researchers are looking into this and have names for them. And, you know, what I said that we would come back to is the big so what? Hannah, you mentioned the guy who would always order a pizza regularly. And then when he stopped, they checked on him. Well, as it turns out, that kind of thing, beyond just job opportunities and, and, and life opportunities are some of the most necessary things we get from strangers. In fact, studies have been done ever since the seventies when, when Mark

• 26:41Speaker 01

  Granovetter first coined the term weak ties to refer to people that were weakly tied to. And they found that the more different types of relationships you have, the healthier you are. There's a correlation between your, your physical health and your longevity as well, and the diversity of types of relationships you have. So it's not just important to have some really close friends. It's also important to have consequential strangers, familiar strangers, even, even intimate strangers in your life.

• 27:24Speaker 00

  I have some questions about the methodology of that particular study. I want to know how you're measuring health. I, I want to know how you are, like over how long are they tracking people? I've got questions.

• 27:38Speaker 01

  Tell, tell me more about your, your question. Like, are you suspicious of that result?

• 27:44Speaker 00

  I would say curious rather than suspicious. But mostly because it feels like it would be really hard to measure concretely.

• 27:50Speaker 01

  Everything I'm sharing today, I researched years up to months ago for a BSauce episode. And I'm giving everyone a little introductory taste. And I even remember writing this into a script draft, that they took people and injected them with the common cold. And then they saw if the outcome would correlate with the variety of social ties that they had, not the, not the variety of the people themselves, but the variety of types of relationships, consequential, familiar, intimate, those kinds of things. So, so yeah, you've got it right in front of you. Tell me.

• 28:26Speaker 00

  No, right. So exactly as you're describing. And you would think it wouldn't make a difference, right? It's like, so you take everybody, you map their social networks, you put them into quarantine, and then just before they leave quarantine, you squirt some common cold up their noses, right? And it's like, why would it make a difference? They've got, it squirted up their noses. Surely they've all got the cold. But in this paper, people who had low social network diversity, so essentially only one to three types of social ties, were four times as likely to develop a full-blown cold compared to people who had highly diverse networks of like six or more ties. So people who are essentially out there in the world, running around the entire time, talking to people, mixing with people, were physically

• 29:11Speaker 00

  less likely to end up. Getting sick despite having the same exposure as people who just sort of sat around at home. Which is wild.

• 29:23Speaker 01

  It doesn't mean that you you have a better outcome if you love your mother more. It means you have a better outcome if you have more different types of relationships.

• 29:34Speaker 00

  If you're out there in the world.

• 29:35Speaker 01

  That's right. The sociology and anthropology department at Illinois State University has been looking into this, especially Susan Sprecher. And she's found that having a more diverse social network that includes intimate others and family, close friends, casual friends, and weak ties acquaintances and other peripheral ties is associated with good health and wellbeing. Indeed, this article says weak ties can give us a real mental health boost. A 2014 study indicated that people with wider connections of weak ties tend to be happier. So not just a variety of different strength of ties, but also the diversity and size of those ties. First of all, I I get how it would make you feel more connected to the world.

• 30:20Speaker 01

  In fact, one famous way of describing consequential strangers versus intimates is to say that intimates anchor us at home, consequential strangers anchor us in the world. So the person at the hardware store who always checks you out, checks you out like, oh, you're looking good. I think that would also be a very consequential stranger.

• 30:42Speaker 00

  I mean, that would be, it's true. The people you fancy on the bus.

• 30:46Speaker 01

  Yeah, those people that we have very few obligations to and yet recognize and interact with anchor us in the larger world and make us feel like we belong, that we would be missed. Obviously, my mother, my wife and my daughter make me feel like I would be missed. But there's a almost unconscious way in which the people we see every day, the coworker whose name we don't really know, but we have a nodding relationship with. All of those contribute to our emotional and potentially even our physical wellbeing. Now, I can see like one strong explanation for the correlation could be that if someone has a large variety of types of social relationships,

• 31:30Speaker 01

  then they probably are also interacting with more people, which means their immune system is getting exposure to a lot more pathogens. Whereas someone who has a close knit group of just intimate friends, but doesn't really get out, they're not exposed to as many pathogens for their immune system to then recognize and be prepared for.

• 31:51Speaker 00

  This is another paper that came out later in 2019, which essentially says, right, we're the social, we're the cognitive social species, right? We are happiest when we are out among others when we're socializing. And the idea is that our immune system treats social isolation as like an active physical threat. And so ramps up inflammatory responses and then suppresses antiviral immunity. So basically, we don't like being on our own and your body is physically happier and more capable of handling actual threats when you're out in the world around people.

• 32:30Speaker 01

  Exactly.

• 32:31Speaker 00

  I need to leave my home office immediately, Michael. This is, it's freaking me out.

• 32:35Speaker 01

  Maybe, maybe. I want to, I want to emphasize that what it means to be lonely is subjective. And it's important that you don't feel lonely. It doesn't mean that you have to be an extrovert who's out among people all the time. For different people, what it means to have a lot of relationships can can change. But I do know that when it comes to cognitive health late in life, so things like like the onset of dementia, we know that one of the best predictors of a a quick decline is whether the person says they feel lonely.

• 33:15Speaker 01

  Now, there are people who do really well and by all accounts externally are lonely. Like they rarely see other people and yet, as long as they don't say they feel lonely, like they feel fine, the amount of social interaction they're getting is fine for them. They have a better outcome. But as soon as you feel that it's not meeting what your needs are socially, that's when there can be trouble.

• 33:41Speaker 00

  Got you, got you. There's a gap that you're yearning for.

• 33:45Speaker 01

  So if you're someone out there who loves bed rotting and you just stare at your phone all day and never leave, that's, that's probably not good. Okay, to be fair. However, if it doesn't bother you that much, it's, it's better than if it does bother you a lot, is what I'm saying.

• 34:05Speaker 00

  But all the same, please enjoy this YouTube presentation.

• 34:09Speaker 01

  That's right. And we will keep pumping out a couple hours of this a week for your lonely pleasure.

• 34:16Speaker 00

  Look, all we're saying is, look, I doom scroll as much as anybody else. But if you're gonna doom scroll, you may as well doom scroll on stuff that's actually enriching your brain, which is what this is.

• 34:27Speaker 01

  And that's a great transition into the next kind of relationship I want to look at, which is a unilateral one. These exist and have existed for all of human history. Unilateral means the friendship, the relationship goes one way. Oh, yeah, Hannah's my friend. But then if you ask Hannah, she goes, I don't really know him. Okay. That is, that is in contrast to a reciprocal friendship where both people independently say that the other is a friend and and consider each other friends to the same degree. Obviously, this can get us into discussions of influencers where a lot of people who follow the influencer

• 35:07Speaker 01

  might have a parasocial relationship with that influencer, where they feel like the influencer is their friend, is closer to them than in reality they are. And certainly, it feels closer than the influencer themselves feel to that person. They probably don't even know that person. So this brings us to the 2015 study out of MIT that looked at a a number of different data sets, a number of different data sets involving social networks where groups of college students or coworkers or community members were asked, here's a list of everyone that's around you. I want you to rate them on a scale of zero to five, with zero being, I've never heard of that person,

• 35:53Speaker 01

  five being they are a, one of my closest friends, where would you rank them? And this kind of study had been done, you know, for decades to look at how social networks build in real life and what it means to be popular, how influence spreads. But what hadn't really been looked at was the unilateralness. How often is it that a person says, oh, yeah, Sarah is my friend, but Sarah doesn't think that person is her friend? And as it turns out, it's really, really common. So I'll tell you what they found. They found that in the friends and family data set, which you'll have to look up what all these data sets are, when they were made and how many people they involved.

• 36:33Speaker 01

  Okay, they found that in the friends and family data set, only 45% of reported friendships were reciprocal. So less than half the time did two people agree independently that they were friends. In the reality mining data set, only 34% were reciprocal. In the social evolution data set, 35%. In Europe's, those are all from America, by the way, the ones I just said. This one, the strongest ties data set from Europe, 49% were reciprocal. And then the personality survey, which is a Middle Eastern survey, only found that 53% of described friendships were reciprocal. And this was really shocking.

• 37:15Speaker 01

  And it's been, it's been found since that, yes, indeed, people are really bad at either evaluating the reciprocity of a friendship or they're just bad at reporting it. One of the most common reasons is that non reciprocal friendships, the researchers have found, are generally aspirational, meaning a person wants to be friends with a higher status individual.

• 37:41Speaker 00

  Yeah.

• 37:41Speaker 01

  But those higher status individuals, where status can mean anything from, from wealth to popularity to perceived coolness, those people have greater choice.

• 37:51Speaker 00

  They've got their own focus elsewhere.

• 37:54Speaker 01

  Yeah.

• 37:54Speaker 00

  Can I just ask you, just remind me, wait, how do they do it? So it's a score between zero and five and you have a full list of names and you put a number against everybody? Or you're limited in the number of people you can score?

• 38:04Speaker 01

  You're limited to scoring people that are on the provided list and everyone on the list is asked about everyone on the list.

• 38:10Speaker 00

  Right. Oh, wow, that's rough.

• 38:12Speaker 01

  Zero to five is only true of the friends and family data set. I don't, I haven't looked at the others, but I I know that the personality survey was zero to seven.

• 38:20Speaker 00

  But it's not like, it's not like someone saying, okay, give me your top 10 friends and then popular people just sort of run out of, run out of places to put friends down.

• 38:29Speaker 01

  No, no, I see what you're asking. No, it really was you have to score everybody on this list. How close are they to you? Would you consider them a a three, which is just like a a friend? Or a really good friend or one of your best? Or are they an acquaintance? Or do you not know them at all?

• 38:46Speaker 00

  Oh, that's so brutal.

• 38:48Speaker 01

  Here's the thing, when you look at the graphs, we can put the paper below, I can share it with you too, Hannah. When you look at the graphs they built with where a node is a person and a line is a connection, you'll also see that there are essentially cliques where a lot of people all consider each other mutual friends. But the connections between those cliques are usually made of unilateral connections where someone in one clique says a person in another clique is their friend, but it doesn't go the other way. So here's the paper coming at you.

• 39:19Speaker 00

  I have to say, as somebody who was, like, I really struggled at school. I really, really struggled at school with friendships. I was so nerdy. I definitely would have been one of the people who, who had only unilateral friendships, who was sort of like, oh, I think this person is my friend, this person is my friend. And then they would never have written me down. Like, I was, I was, I was the kid who was eating lunch in the bathroom. You know what I mean?

• 39:47Speaker 01

  Oh, Hannah, I'm so sorry. Was it because of your red hair?

• 39:51Speaker 00

  I think it was a whole manner of things, Michael, a whole manner of things.

• 39:55Speaker 01

  But look how much you've grown now.

• 39:57Speaker 00

  Look at that. Now people claim to know me on Reddit.

• 40:01Speaker 01

  Oh, that's true. Yeah. So, so the researchers in this paper, they didn't just look at reciprocity and how frequent it is in friendships. They also looked at the way influence happens. And they found quite surprisingly, because a lot of these data sets have been followed over time and different experiments have been done on the same, the same subject pool. And sometimes what's done is, um, studies that use things like the buddy system to see how people can like help each other. They found that when it comes to influencing someone else's behavior, like getting someone to become more physically active, mutual friends do a really good job

• 40:44Speaker 01

  of lifting each other up. A mutual friend is when both people independently say that the other is their friend. But surprisingly, they found that if someone else calls me their friend, that also, but I don't call them a friend, that also influences me. Their behavior is correlated with the change in my behavior.

• 41:06Speaker 00

  That's interesting.

• 41:07Speaker 01

  Just as though we were mutual friends.

• 41:10Speaker 00

  If someone admires you and you spend time around them physically, so it's not like a kind of, you're not strangers.

• 41:16Speaker 01

  That's right. But I don't admire them. I don't consider them close.

• 41:21Speaker 00

  Yeah.

• 41:22Speaker 01

  They nonetheless influence me a statistically significant amount. And yet, if the inverse relationship happens where I consider someone a friend, but unbeknownst to me, they don't really think about me very much. In that case, they don't influence me actually as off as much as you would think.

• 41:41Speaker 00

  Why? That feels like almost the wrong way around.

• 41:43Speaker 01

  It sounds the wrong way around because we call that third kind of relationship, an influencer relationship. I'm the follower. The followee should be influencing me. But they just have not found that to be the case, at least in real life. On social media, it could be different. But I think that this does raise a question that we need more research on, which is to what extent are the influencers actually be influenced?

• 42:08Speaker 00

  Wow, that's interesting.

• 42:10Speaker 01

  Because I can, I can tell you that, you know, you and I here on this podcast, we're influencers, right? But yet, the amount of time we spend as a team discussing comments and how we should title things and what topics we should choose is gargantuan. Okay?

• 42:29Speaker 00

  Maybe we are the influenced. We are the influenced by you, our listeners and viewers. What you like changes what we do.

• 42:36Speaker 01

  Exactly. And all of the subscribers, all of the followers, all the listeners out there, they're the true influencers and they have an extremely powerful weapon that's, that amplifies their influence. It's called the algorithm. The algorithm tells us, hey, this is what they want to watch. You can't just do whatever you want and they'll watch it. This isn't the 1990s with, you know, cable television and whatever's on is on. We're, they're gonna choose and we're gonna let them choose and then we're gonna learn what they like to choose and give them more of it. And so we, the influencers, are much more influenced by the audience than possibly even the other way around. That doesn't mean there aren't exceptions, obviously. There are clearly,

• 43:19Speaker 01

  especially young people who follow influencers and really idolize those people and change their behavior. And yet, the influencer doesn't even know they exist. But by and large, across the human population, we just aren't seeing that influencers actually have the behavior changing effect that we think they do.

• 43:37Speaker 00

  That's amazing. I have a, um, I have a, uh, an example of an exception. It's one of my favorite ever stories.

• 43:45Speaker 01

  Okay, tell me.

• 43:46Speaker 00

  Which is about a tile making company in Hungary and it was having to downsize. But the real problem was that there were all of these incredibly vicious rumors that were flying around the entire company. So it just so happened that they knew this very famous Hungarian network scientist called Barabashi. And so he suggested conducting this mapping, right? Going, let's, let's map this network of influence. Essentially, I mean, there was this whole question there, but essentially the key question was, give me the name of one person you would go to for advice or information. So they asked every single person in the company this and then they mapped the network that resulted. And almost everybody had almost no one. But far and away, the most influential person in this entire company was this entry level employee. It turns

• 44:28Speaker 00

  out, this was the safety officer for the company. So what he was doing was going around to all of these different offices and apparently just bringing all the gossip with him as he went. So then they recognized how powerful it was to have somebody like that. So they, um, just sort of gave him a pay rise and then used him to kind of feed out all the secrets that they wanted throughout the company.

• 44:46Speaker 01

  Oh, yeah. I mean, social influence definitely exists.

• 44:50Speaker 00

  Yeah.

• 44:50Speaker 01

  But the extent to which friendship is part of it and, and whether that friendship is reciprocal is still very much up for debate. I think the safety officer had a lot of arrows pointing to him, but he may have also known all of those people and also counted them as friends.

• 45:10Speaker 00

  True, very true.

• 45:11Speaker 01

  I think that these ideas are all, in my mind, still being formed and, and research is still being done on it. But I think that obviously influencers can, you know, let us know about things. But whether we take an action on them, I think when you think about it, it often also depends on what the community is saying and how they're responding. It's not just the influencers' video alone, it's also the comments. And those comments are coming from people that I am, am, am sort of forming a trust relationship with momentarily. And they don't even know I'm doing it. So it's unilateral. I'm kind of counting them as a friend temporarily, and yet they don't

• 45:53Speaker 01

  even know I'm doing this. They, they don't know who I am. It's those comments and the reaction the community has that lets me know if this influencer is, is going to push or pull me, or if I'm just gonna make fun of them as well. The last thing I want to talk about is the, the scientific fact that your friends have more friends than you do.

• 46:14Speaker 00

  Think for yourself, Michael.

• 46:15Speaker 01

  Look, look, it, it, there, obviously there are exceptions, but as a general rule, it's known as the friendship paradox, and it mathematically must be true. So long as people have friends and they don't all have the same number of friends, this will always be true. The reason it's true is that people who have a lot of friends, people who are really popular, wind up getting overcounted. They're sampled a lot more when you ask any random person, who are you, who are you friends with? So if I'm friends with only two people and one of them is kind of like a special friendship and this person only has one other friend and it's me, okay, there's that. But then I might have my second friend and it's Jim, a guy with 99 friends.

• 46:58Speaker 01

  Of course I'm friends with Jim. He's got 99 friends. We're all friends with Jim. Well, now when you look at it, I've got two friends. But my friends on average have 50 friends. Because those really popular socially central people throw it all off. And this can lead to a lot of illusory perceptions we have of our own popularity. Because as a rule, unless you are one of the most popular people or the most popular person, on average, your friends will have more friends than you do.

• 47:30Speaker 00

  It holds true. You get the same phenomenon on social media. It's like the people you follow have more followers than you.

• 47:37Speaker 01

  Exactly.

• 47:38Speaker 00

  And, and the reality is, it's because you follow, you know, Mr. Beast. I'm just making assumptions about who you're following, Michael, but, um, who has a hundred million followers or whatever it might be. And, and, and therefore, I mean, exactly the same example that you laid out, but just, just sort of scaled up to the size of a population.

• 47:58Speaker 01

  Yeah. And so I think it's a good thing to keep in mind if you ever feel like you're trying to keep up with the Joneses. You feel like, how come, how come it feels like everyone else has more friends than I do? They do, but it's mathematically the case that everyone feels that way. But that's a topological fact. There are other things associated with being popular and with having a lot of friends that also can be described by the friendship paradox. For example, your friends also tend to be wealthier than you. Because wealthier people, they tend to statistically have more friends, have more interactions with more people. Therefore, the same effect happens for the same reason. There are people with a lot of money and a lot

• 48:42Speaker 01

  of friends who throw off those averages and make it the case that your friends on average have more money than you. That they are healthier than you because healthy people are out and about. They're forming connections. They have a lot of friendships. The question I have that's still open, I haven't found research that's recent on this. But this also leads to why young people overestimate the number of risky behaviors their peers participate in. Because there are certain things like going to parties, um, drinking, smoking, that are more prevalent with people who have more friends. Therefore, when you look at your friend group, you go,

• 49:23Speaker 01

  wow, the people that I know and the people that I know of definitely drink more than I do. And everyone feels that way. And it's not just, we don't have to just look at the psychology behind it of, oh, well, everyone overestimates how much their peers drink because it makes them feel better. We can just look statistically at how it's going to happen, that when you go to parties, you see people who go to more parties. And so that becomes the sample that you're looking at. But this has become something that researchers have noticed, um, for real. It's not just a, uh, well, in my armchair, I think this makes sense. But these studies are all a bit older. And I think that in, in recent years, we've seen that young people especially

• 50:05Speaker 01

  are drinking less, they're being violent less, they're having premarital sex less. But in 2005, it was found amongst middle school students that each additional friendship accounted for a 5% increase in the probability that the student smoked. And a 2013 study found that being named as a friend by five additional others accounted for a 30% increase in the likelihood that that middle schooler had tried alcohol.

• 50:31Speaker 00

  Here's the thing, Michael. I can, I can hear you're reading this and you're saying, no, look, the friendship paradox demonstrates that you have an incorrect perception or a warped perception of how important these individuals are across the entire population. Sure, I appreciate that's what you're saying. But all I'm hearing is. You get more friends if you go to parties and you get more friends if you're drinking and smoking. And maybe that was the mistake that I've been making since 2003. Maybe I should be at parties more.

• 51:01Speaker 01

  Exactly. If you'd gone to more parties, then you would have probably partaken in more of these activities.

• 51:08Speaker 00

  I'd have actual friends. Redditor, hit me up, okay?

• 51:13Speaker 01

  And so, anyway, this, this kind of explains why especially young people tend to overestimate the behaviors of their peers when it comes to things like drinking and smoking. But I'm wondering if it's different today. I think there might be other traits that correlate with popularity today. For example, maybe your ability to communicate and be effective on social media. It might lead to a feeling of, well, everyone else is so much better at social media than me. And that's because the ones that you see are the ones who are good at it, and they wind up having more connections. And you, you are more likely to know of them and be a friend or follower of theirs.

• 51:55Speaker 00

  I also wonder about gyms being the new party places, you know?

• 51:58Speaker 01

  Yeah.

• 51:59Speaker 00

  Gym, gym bunnies have a lot of friends. They're, they meet them in the gym.

• 52:03Speaker 01

  Yeah, exactly. And so I'm, I'm quoting studies that are more than, you know, 10, 20 years old.

• 52:09Speaker 00

  Yeah.

• 52:09Speaker 01

  And I wasn't able to find much about how teens especially evaluate the frequency of certain behaviors of their peers. So I don't know how this works today, but I do think that the, the math will still hold, that whatever other traits coincide with popularity will also be overestimated by the rest of the population as being prevalent.

• 52:34Speaker 00

  One of the things about the friendship paradox that, that I've always thought is that it's sort of an artifact of, of the idea that like means, you know, averages using a mean is, is not a useful way to think about stuff, right? That, that, that's sort of the, the, the, the things I think about it. There's network effects. There's all of that. Sure. But one of the key things is that you're taking a distribution of individuals, some with very large numbers that are, that are overrepresented, sure. But then when you take the average, it's just the whole, excuse the average. And, and the thing I like to think about is that you have an above average number of arms, Michael. So do I. In fact,

• 53:15Speaker 00

  limbs in general, right? Or like the average person has slightly less than one boob, you know? It's like, actually, when you use means, sometimes they don't make any sense. You could apply this this way, which is that your friends have less arms than you, on average.

• 53:36Speaker 01

  Because you probably statistically have two arms. And yet, if we fan out to all the people you know, there will be people who have fewer than two arms, and they'll drag that average down. So your friends have fewer arms than you do, statistically.

• 53:53Speaker 00

  On average, yeah.

• 53:55Speaker 01

  On average. And, and by the way, that also brings up the enemy paradox, which is the same thing, which is that your enemies have more enemies than you do.

• 54:04Speaker 00

  Hmm. That one feels better.

• 54:06Speaker 01

  Yeah, exactly. So, so it just depends on what data you want to meditate on, how well you feel.

• 54:12Speaker 00

  That also sort of makes more intuitive sense, I think, because of course, my enemies are absolute assholes, and everyone hates them, not just me.

• 54:20Speaker 01

  Yeah, see, exactly, exactly. It's just math. So keep this in mind. When you compare yourself to other people, you're comparing yourself to a group that isn't an arbitrary sample of the population. It is weighted towards those that you will be aware of. It's weighted full of people who are more connected and popular than the average person. Therefore, it's not a fair comparison. I don't know, that actually doesn't make me feel that much better. It just makes me remember that there are people who are doing much better at forming friendships and being popular than me.

• 54:53Speaker 00

  Look, it would have been, it would have been little comfort to me in the bathroom stall of Presdeale School in about 1998, you know, as I tried to eat my lunch.

• 55:05Speaker 01

  That's right. It doesn't really work. You know, mom, I'm, I'm feeling bad about myself. Well, just remember that a few people are amazing, and they're so much better than you, that they throw off the average. But in general, a typical person chosen at random could be worse than you. Do you feel better now, Michael?

• 55:24Speaker 00

  Look, our job here is not, is not to make anyone feel better. It's to expand your minds, tickle and tease you with the absolute best of what science and psychology and mathematics and philosophy have to offer. And I feel like we've done that, you know?

• 55:36Speaker 01

  Exactly. What we have to offer is reality and humility. And I am really glad to hand that out. I think the most magical thought that, that has happened in my mind during all of this is just that reflection on the fact that I am someone else's familiar stranger. I'm part of someone's life, and I don't know it.

• 56:00Speaker 00

  And everyone is.

• 56:01Speaker 01

  And we all are. All of you out there listening are a part of our lives, and you might actually be the true influencer here. So thank you for being who you are.

• 56:11Speaker 00

  This is very true. You can continue to influence us by emailing [email protected] or by leaving a comment here, whenever you're getting this podcast.

• 56:21Speaker 01

  Exactly. See, look at that. They can email us, but I can't email them.

• 56:25Speaker 00

  No, no. This is, this is a, this is not a reciprocal relationship in the wrong direction.

• 56:31Speaker 01

  How the tables have turned, Hannah.

• 56:34Speaker 00

  How they have turned.

• 56:35Speaker 01

  We appreciate you guys. Have a good day, and we'll see you later.

• 56:38Speaker 00

  See you next time.

• 56:51Speaker 06

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