Robin Dunbar - Optimizing Human Connection (Dunbar's Number) - [Invest Like the Best, EP.367]

My guest today is Robin Dunbar. Robin is a biological anthropologist, evolutionary psychologist, and specialist in primate behavior. He is the man behind Dunbar’s number, a theory about the number of stable relationships we can maintain at once. Robin unravels the thread of research that led him to Dunbar’s number and describes how this plays into every single person’s layers of human connection. It was fascinating to hear how his findings on social circles have implications for optimally structuring businesses and organizations, as well as the idea of homophily, all of which Robin thoughtfully explains. It was a treat to get to explore these topics with Robin Dunbar himself so please enjoy this great conversation. Listen to Founders Podcast For the full show notes, transcript, and links to mentioned content, check out the episode page here. ----- This episode is brought to you by Tegus, the only investment research platform built for fundamental investors. Whether you’re trying to get up to speed on a new market or keep tabs on a portfolio company, Tegus is the end-to-end investment research platform you need. With Tegus, you can quickly understand a company's business model, drivers, benchmarks, and management quality. To monitor an entire market, download our pre-built financial models — or update your own with the latest data using Tegus’ new Excel Add-In. Tegus gives you all of this and more, all bundled into a single software license. Find out why 95% of the top 20 global private equity firms are Tegus customers. Learn more and get your free trial at tegus.com/patrick. ----- Invest Like the Best is a property of Colossus, LLC. For more episodes of Invest Like the Best, visit joincolossus.com/episodes. Past guests include Tobi Lutke, Kevin Systrom, Mike Krieger, John Collison, Kat Cole, Marc Andreessen, Matthew Ball, Bill Gurley, Anu Hariharan, Ben Thompson, and many more. Stay up to date on all our podcasts by signing up to Colossus Weekly, our quick dive every Sunday highlighting the top business and investing concepts from our podcasts and the best of what we read that week. Sign up here. Follow us on Twitter: @patrick_oshag | @JoinColossus Editing and post-production work for this episode was provided by The Podcast Consultant (https://thepodcastconsultant.com). Show Notes: (00:00:00) Welcome to Invest Like the Best (00:04:39) The Journey to Discovering Dunbar's Number (00:07:28) Exploring the Layers of Human Connection (00:12:27) The Significance of the 1.5 Layer in Social Circles (00:16:55) Surprising Insights from Social Network Studies (00:20:40) Applying Dunbar's Number to Organizational Structures (00:27:51) The Science of Social Bonding in Primates and Humans (00:33:23) Unlocking the Endorphin System Without Physical Touch (00:34:10) The Power of Laughter, Singing, and Storytelling in Group Bonding (00:36:00) The Limitations of Digital Interactions for Building Relationships (00:39:51) Reviving Social Clubs and Activities for Workplace Bonding (00:44:40) The Importance of Homophily in Friendships and Social Networks (00:50:40) Challenges and Solutions for Overcoming Loneliness and Building Trust (00:53:45) The Impact of Technology, Religion, and Mental Health on Social Connections (00:61:47) Reflecting on Time as a Fundamental Aspect of Social Dynamics

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Patrick O'Shaughnessy?

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• 0:35Patrick O'Shaughnessy?

  Hello and welcome, everyone. I'm Patrick O'Neal and this is Invest Like the Best. This show is an open-ended exploration of markets, ideas, stories and strategies that will help you better invest both your time and your money. Invest Like the Best is part of the Colossus family of podcasts and you can access all our podcasts, including edited transcripts, show notes and other resources to keep learning at joincolossus.com.

• 1:00Speaker 01

  Patrick O'Neal is the CEO of Positive Sum. All opinions expressed by Patrick and podcast guests are solely their own opinions and do not reflect the opinion of Positive Sum. This podcast is for informational purposes only and should not be relied upon as a basis for investment decisions. Clients of Positive Sum may maintain positions in the securities discussed in this podcast. To learn more, visit psum.vc.

• 1:29Patrick O'Shaughnessy?

  My guest today is Robin Dunbar. Robin is a biological anthropologist, evolutionary psychologist and specialist in primate behavior. He is the man behind Dunbar's number, a theory about the number of stable relationships we can maintain at once. Robin unravels the thread of research that led him to Dunbar's number and describes how this plays into every single person's layers of human connection. It was fascinating to hear how his findings on social circles have implications for optimally structured businesses and organizations, as well as the idea of homophily, all of which Robin thoughtfully explains. It was a treat to get to explore these topics with Robin Dunbar himself, so please enjoy this great conversation.

• 2:10Patrick O'Shaughnessy?

  Well, Robin, thanks for doing this with me. I have to start with the obvious question, which is, I would love to hear the story behind you arriving at the incredibly famous Dunbar's number.

• 2:21Speaker 02

  Oh, my goodness. How long have you got?

• 2:23Patrick O'Shaughnessy?

  I got a long time.

• 2:25Speaker 02

  Quite a convoluted story, really, actually, because there was a proposal made back in the late 80s. The reason primates, monkeys, and apes had much bigger brains than anybody else was that they lived in complex societies and therefore needed a big computer to manage this. But it was based on largely casual observation as much as anything. And that was a real problem, because primates do have much bigger brains. This stuff is expensive. Why would you be carting around all this heavy-duty computer-consuming energy like Fury if you weren't doing anything different to what everybody else is doing? So, anyway, this suggestion was made to do with the complexity of their social systems. And I had the bright-eyed

• 3:08Speaker 02

  idea one evening, when I was trying to solve a completely different problem, which is why primates groom each other, that if that hypothesis is true, then we ought to find correlation between some measure of group size in primates and their brain size. And so I collated data on group sizes, and I collated data on brain sizes. I stacked them together, and sure enough, there's a very nice relationship. And now we're about 3 o'clock in the morning and getting quite excited about how this is going. It occurs to me that we should be able to use this to predict what humans' group sizes are. So I did. This gave me a number about 150. So I then spent, obviously, the rest of the night and several

• 3:53Speaker 02

  other days and nights, sitting in the library, looking for data on natural human group sizes. Metropolises like New York and London and Tokyo in mind, they're all very recent things, barely a century old. We spent most of our time in small-scale hunter-gatherer groups, just looking for data on the size of these groupings. Because they're quite complex grouping is not just a single group. Hunter gatherers like we do live in sort of multi-layered social systems. So I was looking for a layering within their social systems that was about one hundred and fifty in size, rather than, say, two thousand or twenty-five. And sure enough, there is one.

• 4:37Speaker 02

  It's generally called a clan or a regional grouping or something like that. It's basically a unit that shares hunting territory as much as anything, that shares the rights to territory, let's say. They don't necessarily all live here. And after that, we just kept finding this number everywhere, everywhere we looked in the modern world. Our entire modern world is built around this number, one hundred and fifty.

• 5:01Patrick O'Shaughnessy?

  Can you explain the scaling up and scaling down of the number, the sort of dividing by three or multiplying by three, and the fact that you then see this bizarre nesting or layering everywhere too? So it's not just the one fifty, but it's these other scalar versions of Dunbar's number as well?

• 5:20Speaker 02

  Think of it best in terms of your personal social network, all the family, extended family and friendships you have. If you look at those and the frequencies that you contact them or how emotionally close you feel to them or your willingness to do them a favor that would cost you something serious, not a question of just putting a dollar in a beggar's box, as they say, but actually giving them a significant amount of money they asked you to lend money for a project. All of these reveal a kind of layered structure, and that layered structure looks pretty much like the ripples on a pond where you throw a stone into a lake, for example.

• 6:04Speaker 02

  So if you think of yourself as the stone surrounding you, these layers moving out from you. And as you go further and further out, the area covered by each ripple gets bigger and bigger, but the kind of amplitude of the waves, the height of the wave gets lower and lower. And that's quite a good metaphor for what your social world looks like. So you have these series of layers going out from you, which increase in size, but the quality of the relationship and the frequencies that you contact them gets smaller and smaller and smaller, lower and lower as you go further out. So these layers occur at very, very specific numbers. Core is really this hundred and fifty number, Dunbar's number.

• 6:47Speaker 02

  But within that, there are a series of layers, fifty, fifteen, five, and the smallest one, one and a half, one point five. And then beyond the hundred and fifty, going out further, there are layers at five hundred, fifteen hundred, and the last possible one is five thousand, because five thousand identifies the number of faces you can say whether you've seen them or not before. In other words, it's the distinction between a complete stranger, I've never seen that face in my life, and somebody you've seen, but you probably, for most of them, you don't know much about, you don't even know their name maybe. But then the fifteen hundred layer within that, which actually turns out to be the

• 7:32Speaker 02

  typical size of tribes in hunter gatherer societies, the distinction there is that you can put names to faces. So for all of us, whether you like it or not, nice Mr. Donald Trump is in your fifteen hundred layer. But that's only because if you saw him in the street downtown, you would recognise him straight away. But if you kind of wandered up to him, slapped him around the shoulder and said, Donald, come and have a drink with me, he would look very surprised. I'm sure he'd be a good politician and pretend not to be. But so it's that kind of relationship. And as you come further in, the five hundred layer is the layer of acquaintances. Many of the people you work with will be in that layer. In other words, you might go and have a beer with them after work.

• 8:15Speaker 02

  You might even spend a weekend away for some big work-related project with them, but you would never invite them back to your home for a big party. Your hundred and fifty layer, well, that's what I always call your bar mitzvah weddings and funeral party. These are the people who will turn up out of obligation to you on that big once in a lifetime event. You may not know they're there, the third case, the funeral party, but believe me, they'll be there. And then as you come in, so the relationship's getting stronger and stronger, you go through the fifteen layer is your sympathy group, people who you would feel extremely upset about if they died. That's Been known for a very long time. I didn't discover that.

• 9:00Speaker 02

  And then inside that is this layer five, the cinema's layer, which is what we call the shoulders to cry on friends. And that layer turns out to be very important for you. Usually consists of two family members and two friends plus an odd one from either side. That number turns out to be the one that has the most influence on your general health and wellbeing. So the best predictor of your mental health and wellbeing, your physical health and wellbeing, and even how long you're going to live into the future from today. Is predicted by the number and quality of friendships you have in that layer. The five is an average. So if you only have three, don't panic yet, but because introverts tend to prefer to have fewer people, but have stronger friendships.

• 9:45Speaker 02

  As a result, extroverts tend to prefer slightly more people, but have weaker friendships, those kind of effects. But on average, very much five. So as I like to say, if you really want to live forever, just make sure you've got five friends.

• 10:00Patrick O'Shaughnessy?

  And what about the 1.5? That seems like a odd number in the end of the cycle.

• 10:04Speaker 02

  I always used to sort of come out with this joke when I was giving talks, because I actually thought it was a joke. Which was, well, just look at these series of circles and how very tight the kind of fractal mathematical structure is. Each layer is three times the size of the layer inside. And remember, these layers count cumulatively. So the 150 layer includes the 50 people in the layer inside. It's not an addition. But just look at the regularity of this structuring of these numbers and surely there's a layer missing. If you project backwards, because we only knew about the five, we thought the five was the smallest number. If you project backwards, there's a number missing. And what is it? Well, it's one and a half. And everybody'd say, how can you have one and a half relationships?

• 10:49Speaker 02

  The answer is obvious. Think about it. Half the population has one.

• 10:55Speaker 02

  Very, very close friend in that circle. And the other half the population has two. What might the difference be? Well, the answer is gender. It's obvious. And if you want to know which way it goes round. He says jokingly, well, it's men only have one in that circle and women have two. And that was kind of pulling the leg of the audience, really, because the audience automatically goes, aha. That's your your romantic relationships. Clearly, women have one and men have two. Yes, the other way around. And then my collaborators in in Italy, who are analyzing Facebook data. And said, you know, we get this layer at one and a half. We think we must have made some error here. They were looking at the frequency of postings and showing very nicely.

• 11:40Speaker 02

  You get these, you can identify these layers, but they'd found this extra layer. And I went, what? What an half? Perfect. That's it. What's it all about? Well, we don't know. So when we looked into it, yes, it's true. And the question is, why are women having two? And the answer is they have a platonic friend called a best friend forever. BFF. And that's nearly always another woman, not hundred percent, but eighty five percent of women at any one time. Have a best friend forever. Because the social psychologists who've explored this question. Have told us that constant reason that women always give is because their romantic partner, who statistically obviously is usually a male.

• 12:23Speaker 02

  Is completely useless at emotional issues. You need somebody else who's better qualified to deal with emotional issues. To sort of deal with that part of your life. And the only person that falls into that little bracket, as it were, is is a girlfriend. Interestingly enough, when they have a male, fifteen percent of them are male, those males tend to be much more feminized. Than the average of ours. And they're often gay men, for example. And what's interesting is that you can ask a guy, do you have a best male friend that kind of do stuff with? And very often they'll say, yes, Jimmy. Jimmy and I go for a beer together now and again. We've known each other since primary school.

• 13:07Speaker 02

  And you explore a bit further the quality of that relationship, but you go, this is not a best friend forever. It's completely different because if Jimmy decides he's going off to Thailand for the rest of his life, it is a case of out of sight, out of mind. If he comes back again, you could pick up where you left off, no problem. But while he's not there, it's really a case of out of sight, out of mind, which will never, ever happen with women, their close friendships. They're on social media, they're on the phone, whatever, trying to keep that relationship going and keep it ticking over. And guys don't do that. What's interesting in that particular context, though, is that it's very clear that men either have one or the other.

• 13:49Speaker 02

  That's why they only have, appear with one, if you like, in that layer rather than the one and a half or the two that the women have. Of course, it's the average of the male's one and the women's two that makes the one and a half for that layer. But men tend to have either a romantic partner or a best friend. So if they don't have a romantic partner at the time, or these things happen as you get older, the intensity of a romantic relationship cools, as you might say politely. And then they might reinstitute a male best friend that they hang out with.

• 14:25Patrick O'Shaughnessy?

  I'm sure that you have looked at an incredible amount of data and that the internet and social networks and just the world of digital data has exploded your ability to explore these ideas and these numbers. What has been the most surprising data that you've ever encountered in or around your ideas?

• 14:45Speaker 02

  There are two prizes potentially here. One was a very notorious study of Facebook, which was published in a very eminent journal about 10 years ago, which became notorious because they'd used Facebook to manipulate people's feeds because they were interested in trying to understand what influence feeds had on people's perceptions of the world. What we all worry about, nice Mr. Putin, sending us endearing messages on our Facebook pages to vote for one president candidate or another presidential candidate, according to the one he would really prefer. There are serious issues behind this, but I'm afraid they got into a lot of trouble. Anyway.

• 15:26Speaker 02

  They have sixty one million, as I recall, Facebook pages that they worked with. That's a huge sample, ginormous, probably talking about, what is it? One percent of all the people, billion people on Facebook or something of that order. Huge, huge sample from all over the world. And they came out with an average number of friends on Facebook of a hundred and forty nine. Wow. Now, believe me, if you work on animal behavior or human behavior like I do, you do not often get predictions that come out that close. So I think on the strength of that, I'm entitled to go, go past go, cut my two hundred dollars and retire to the Caribbean.

• 16:08Speaker 02

  The other one was really cool because we'd done a lot of work and a lot of other people had started to work on which bits of the brain are involved in this and showing that you can predict the number of friends that people have in their social circles, friends of family, of course, by the size of particular regions in the brain. Turns out to be a particular huge neural network that we use to process social information. There was some Korean guys who did an entire village. What they did was kind of neat because most of the time what we're having to do is to ask people, how many friends have you got? How many friends have you got on Facebook? Check, write down a list of all the friends and family you have. Who are you phoning? Let's look at your phone calling records on your cellphone.

• 16:51Speaker 02

  So we're always looking at it from the individual's point of view, you know? Well, you know, okay, you can argue the list of people I phone regularly looks fairly hard-nosed and convincing, but you know, there may be people that I actually have close relationships with that I don't phone because like they kind of live next door or in the same house, so I don't bother to phone them. And if I ask people just who are your friends? Famously, if you ask sort of kindergarten and primary school kids, who are your friends? They'll say, you know, Jimmy, Susanna, Penelope, and then you go to Jimmy, Susanna, Penelope and ask them, are you friends with so and so? And they'll say, what? Never. So who knows if the data we have is really reflective of the relationships.

• 17:35Speaker 02

  And what these Korean guys did is they went to everybody else in the village and said, are you friends with each person? Right? So it was the friends' evaluation of their true relationship with you that identifies the number of friends that you as an individual heard. And what they showed very nicely was that indeed the number of friends that Everybody could claim because these people said, yes, I'm their friend correlated with the size of these same regions in the brain. So I think that was quite spectacular, really. They were able to do something which nobody else had actually been able to do.

• 18:12Patrick O'Shaughnessy?

  What do you think are the most interesting implications of this understanding of how we work in groups? These seem to be almost just latent features of our species and of other primates, too. Is there something to do with them that you think is the most productive? And or like, did you change your behavior, having discovered all this in your own life? What's the news you can use here in your opinion?

• 18:38Speaker 02

  You mean, did I look at my friendship circles and go, oh, my goodness, I need to get out more?

• 18:43Patrick O'Shaughnessy?

  Something like that.

• 18:43Speaker 02

  Well, it does happen when you do this kind of research. In the end, what's important about these circles? And here's another interesting feature, actually, this we hadn't quite expected, is that it turns out that this relationship between brain size and group size in primates is not a single homogeneous set of data. So the data points don't lie on the same line, which is ideally what you want. They scattered quite widely around it. And it's turned out since we've only recently been able to show this finally statistically. In fact, that relationship consists of four sets of statistical relationships. So they're

• 19:22Speaker 02

  like four grades and the grades differ in both group size and cognitive complexity that the animals are using. So these grades have real meaning. It turns out that the layers for our social networks, for these values in this fractal series of fifty, fifteen, fifty, hundred and fifty, five hundred, fifteen hundred, actually fall on these grades beautifully. And we see the same structure in primates. And so this is number four, really. So that was number three surprise. Number four surprise was to find that this was the same thing was true of primates, the species like chimpanzees and baboons, which have complex, multi-level

• 20:03Speaker 02

  social systems, the layers within their social groups, created again by the frequencies which they interact with each other, the strength of the friendships, if you like, also fall on these layers. So something about these layers. Which is these numbers, which is kind of magical in this sense. And so this is number five surprise, actually, with a bunch of US mathematicians, we were able to show that these numbers, five, fifteen, fifty, hundred and fifty, five hundred are actually optimal points in the efficiency with which information flows around networks. If whatever your group

• 20:43Speaker 02

  is hits one of these numbers, then it works as an integrated group somehow. We didn't quite understand why this happens, but it seems to work in a much more efficient, integrated, cohesive sort of way. But if you're in between, things kind of fall apart. So there are all sorts of implications here for the structure of organizations and businesses in terms of how they organize their departments, how they organize their work groups. For example, you want to hit these numbers and the numbers themselves are derivative of the quality of the relationship involved and the emotional fit, if you like, that you have with a person

• 21:25Speaker 02

  in one of these layers. And one of the implications of that is if you've got a task, develop a bit of code for some computer program or a figure out some processes and allow you to produce a kit of the kind that you make and sell to the public. And maybe it's a service you run for your government department program for running street lightings or something like that. It's best to have a very small group. They will work much faster and much more efficiently, but they need to know each other in the sense that they all come from the same background. So one of the things you mustn't do here is go, oh, we ought to have somebody from finance and

• 22:08Speaker 02

  maybe somebody from HR because they'll get sort of very upset if they're not included. And the answer is don't resist the temptation like crazy. Because what you want at that problem solving thing is for people that don't have to explain everything to each other. So they just know when I say, right, it's what we want to do here. Everybody goes, sure, absolutely. They're all on the same page. They all understand the background and the mechanisms and everything else. Okay, if it's a financial issue, then you want somebody from finance. Maybe if it's a kind of H R type issue, then you want somebody from human resources. But don't include people, which is the temptation we have in organizations.

• 22:52Speaker 02

  And it's to add people from different departments in as sort of representative as it were. The answer is don't do it. There is a place for that, and that comes further up the scale. And as you go further up the scale in terms of work group size, you go through different functional things. So the fifteen layer really works much better for blue skies banding ideas about. And then it's much better to have a diverse group of people who are coming at the problem with different perspectives. Things that another area has already figured out. They'll be able to sort of look over the parapet and say, oh, because this is what this is how science works.

• 23:32Speaker 02

  There's science, all the big innovations in science have come about by somebody from a completely different discipline. Usually poking their nose over the parapet and going, oh, that looks like an interesting problem. What's it all about? And you explain it to them and they go, oh, that's very like what we have just solved the problem for. But we know how that works. Why don't we just apply the same methods or mathematics or whatever it is to your problem? And it might work. And very often it does break a logjam. And likewise, think about the optimal size of boards. For example, it's going to be one of these numbers. It's probably not going to be below fifteen because you want a really wider representation. But you certainly probably don't want to go above fifty.

• 24:15Speaker 02

  Like looked with horror, the size of the committee for.

• 24:20Speaker 02

  Climate change, one hundred and fifty to two hundred, you think.

• 24:24Patrick O'Shaughnessy?

  Nothing's gonna get done.

• 24:25Speaker 02

  Part of the problem is feeling that you make a commit contribution. There's only so much speaking time that's available. Unless you're gonna sit there for a year, by which time, of course, you've forgotten what the first person said. So you've got to bear in mind that speaking time is very limited. The issue is that if you have too big a group, you end up with people who just sit there and get bored and end up looking at their feeds or their emails on their smartphones. And this is exactly what we found during lockdown. Zoom and Teams and people trying to maintain contact with work group or departmental group, whatever it may be. So you'd end up with lots of people on a Zoom meeting.

• 25:08Speaker 02

  And the problem is, realistically, you can only have four people engaged in a conversation. So it would just get dominated by the four people with the loudest voices. And everybody else would kind of get bored in the background. So they ended up wasting huge amount of time.

• 25:24Patrick O'Shaughnessy?

  You mentioned at the beginning that you were studying primate grooming. And that brings to mind a question about the quality or nature of the time that we spend with the people in these different layers of our social structure. And I'm sure that time is not created equal, like different activities function for different reasons. And I'm really curious what you've learned about the way that we spend time with each other. What's important, what's surprising, what are some implications at the different layers? Like the things we actually do with each other, what have you learned that's most interesting there?

• 25:53Speaker 02

  This really all goes back to, I mean, there's like intimated several times. The layers are created by essentially the amount of time you spend doing stuff with different people. So obviously, the inner core layer, these layers in your social network have very specific frequencies of interaction you must have to keep the person in that layer. So the people in your inner five shoulders to cry on friends layer, you have to see at least once a week. That's the minimum. The people in the fifteen sympathy group layer next outside it, you have to see at least once a month. If you see them less, those relationships decay inexorably. Takes about three years for somebody to go from being a member of your sympathy group, your fifteen sympathy group,

• 26:38Speaker 02

  to falling out of your hundred and fifty and joining the layer of acquaintances, which includes your favorite barista that you get your. Glace coffee from every morning on the way to work and that kind of thing. So there's some of our ones knew that don't have a meaningful relationship with. But I wouldn't invite them home. And it's very clear that that happens. We can show that actually happening with data from people's networks. So you have to invest time in relationships in proportion to essentially the emotional closeness. And it turns out that emotional closeness of a relationship is highly correlated with the time you invest in it. Question is, what are you doing? Well, we just step back a moment to what monkeys and apes are doing.

• 27:23Speaker 02

  Monkeys and apes spend a lot of time grooming each other. It turns out this is how they bond their relationships, how they create their social bonds, as it were. The intensity of these relationships, which mean they'll stick by each other. They won't allow one person to drift off into the bush where they get lost from the rest of the group and these kind of things. They're keeping it on. What that's involving is an awful lot of time spent grooming. And the amount of time spent grooming correlates with the size of the group in permits. To the extent that some of the most social species who are typically living in group sizes of about 50 individuals. So smaller than us, but it's that second inner layer from the 150.

• 28:06Speaker 02

  They're spending about 20% of their total available daytime engaged in this one activity, social grooming. Partly because of the number of individuals they're grooming with. But actually, as their group size is increasing, they're spending more time grooming as a whole. But actually, what they're doing is devoting more time to each individual. They're not necessarily grooming with more individuals, or at least not proportionally more individual. They're making those relationships more intensive. And the reason that works is grooming triggers the endorphin system via a very specialized. Neural system from the skin, which we all share, we have it too. This system responds to light, slow stroking only, no other action on the skin.

• 28:50Speaker 02

  It doesn't respond to temperature or pain or anything like that. Just responds to light, slow stroking at around about three centimetres a second, which is the rate during grooming where they're stroking the fur part of it, deforming the skin underneath as it went. This is what's triggering the system off. If you try stroking someone slower than that or faster than that, there's no response. But get it right and they get an endorphin hit in the brain. Endorphins are part of the brain's pain management system. They give you a kind of opiate-like high. You feel very relaxed and calm and peace with the world and trusting of the person who's doing this activity. It's highly specialised. We use it all the time. Turns out the inner ear is full of these receptors.

• 29:34Speaker 02

  This is why we nod our heads when we're listening to music or dancing. This is why we rock babies. If you rock them at around about three centimetres a second speed, they calm down and go to sleep nicely. If you try it slower than that, one centimetre a second, or try it faster than that, thirty centimetres a second, it has absolutely no effect. They carry on crying relentlessly. They have to get it absolutely right. So that's the basic mechanism. We've shown that that still works with us, demonstrably still works with us. That system underpins the quality of our friendships. The problem for us is that, and for primates actually, monkeys and snakes, is grooming because it's physical touch.

• 30:16Speaker 02

  The intimacy of that limits its capacity. So there's a limit to the number of individuals that you can engage with and build relationships with through this mechanism. And that sets an upper limit on group size, actually, at about fifty animals. So the problem we had during the course of our more recent evolution, as we're, if you like, trying to increase the size of our groups up to the hundred and fifty we have now, was how to bond these groups, particularly though, okay, you can go around grooming kind of inner core within the fifty layer, but how do you bond the other hundred people that sit in the final hundred and fifty layer? The answer is we found lots of ways that allow us to trigger the endorphin system

• 31:00Speaker 02

  directly without involving physical touch.

• 31:04Speaker 02

  And these are in order with which they appeared in the course of human evolution. We think laughter, singing, dancing, and then once language evolved, which was probably only with the appearance of our, or at least fully modern language with our own species, two hundred, two hundred fifty thousand years ago. Lots of things derivative of language, including the rituals of religion, feasting, eating together, drinking particularly alcohol together. Stringent type things, alcoholic type drinks, trigger the endorphin system big time. And lastly, telling emotional sob stories, great tragedies. And we've shown with all of these that they trigger the endorphin system and they increase the sense of bonding

• 31:49Speaker 02

  with the people you actually do the activity with. So it doesn't change your relationships with people who are your best friends who are not there on the day. But it does affect the quality of the relationship you have with a complete stranger who happens to be there. And we've shown this with neuroimaging experiments, pain threshold tests with blocker experiments where you're giving people drugs that block the receptors for endorphins in the brain. They do the activity, but they don't get the hit. And all these cases, you can show very nicely that these peculiar activities, what I call our social toolkit, work extremely well for bonding large groups and they vary in the size of group that they can bond. Laughter ironically is one of the smallest.

• 32:33Speaker 02

  There is a natural limit on the size of a laughter group at about three, very close to the limit on the size of a conversation group. Still, three is three times, that means you're bonding three people together at the same time. Whereas with grooming and physical touch, if you were just to stroke them physically, you would only be able to bond one person. So already laughter is three times more efficient. Singing is amazing. We call it the icebreaker effect. Community singing around the campfires can turn a group of complete strangers into a group who think they were all at primary school together. They're telling them each other their life stories and great secrets and stuff. It's just amazing.

• 33:14Speaker 02

  Singing works minimally for groups of up to 200 people we've done it with. And it was showing no sign of tailing off. It's still, the bigger the group, the better the effect. So taking, see a lot of these things, kind of a part and parcel of the things we do every day with our friends.

• 33:32Patrick O'Shaughnessy?

  Can I jump to a conclusion that it's an enormous waste of time to just do like a normal run of course Zoom meeting all day for work? That Zoom does not create endorphins in the same way that any of the stuff that you've listed? If relationship drives everything, then this seems like a giant waste of humanity's time.

• 33:50Speaker 02

  Yeah, I think the answer has to be yes. It can be efficient, clearly. Any of the social media, including the telephone after all, can be efficient for processing and dealing with some issues at work, and particularly when people are not present. It is sort of okay for bonding people who already know each other well. So this is why we're pretty sure the reason Facebook was so successful is that it allowed people who had now separated, just remember when it was first set up by Zuckerberg and people that, you know, these were final year kids at college about to disperse all over the United States. Their big buddies for the last three or four years, you know, suddenly they would not be able to see them easily.

• 34:35Speaker 02

  How do you keep in touch? Here's your answer, join Facebook. And we think that worked very well and did because what it's doing was acting like a sticking plaster. It slowed the rate of decay down by allowing you to keep up with the person. But we think that, and the general experience seems to be that if you don't meet up once in a while, face to face, nothing on earth, or Facebook is going to stop. That friendship gradually becoming an acquaintanceship. Yeah, it's just somebody I once knew, haven't seen for years, don't really know what they're doing. Check their feeds now and again, but I don't waste a lot of time. So there's something about face-to-face interactions that's very important.

• 35:18Speaker 02

  And the world of business is a village. Works best if it works like a village where everybody knows each other. So if, as a default, the only way you've got for people to meet up is online, that will kind of do, but it's a bit clunky. And it's difficult to see whether it would, in the long run, work terribly efficiently, because you're not able to do all the kinds of casual things we would do with people, certainly with our friendship circles. But we do with people at work. We laugh with them, we have lunch with them, we go out for a beer with them, we tell them all our troubles of our lives. And there are rituals, as the analog, as it were, of how religion works.

• 36:01Speaker 02

  Any organisation has its own internal rituals that it does in some form. And if you were in Japanese industry until about 20 years ago, everybody stood by their desks in the morning and did calisthenics for 10 minutes. And I'm absolutely convinced this is why the Japanese car industry ended up being so successful. They've lost their way a bit. But we used to kind of looking at Japanese car companies, everybody's doing gymnastics and tai chi type things in the car park before they went into work, say, ha, ha, ha, you know. Well, I think laughing was on their side of the face, not our side of the face,

• 36:43Speaker 02

  because that made them feel very bonded and committed to the company. And that was real symptom, if you like, of Japanese industry at that time, when they were peaking in their productivity is, is that every worker, from the big boss at the top to the person who swept the belt, they belonged to the company. They had this expression, I am a company man, meaning this is my life and my commitment. And I think that had a lot to do with these things, because what these exercisers have been doing is triggering the endorphin system, making them feel very cool, calm and collected and at peace with their fellow workers and with the company in general. So these mechanisms kind of play a role, but it's underneath. And I think it's sort of going on below the surface of consciousness.

• 37:27Speaker 02

  And I think in our haste to find efficiencies, we've forgotten the lessons, actually, of the founders, the entrepreneurs who founded the big multinationals of today, back in Victorian Edwardian times, 150 years ago, because they all recognised.

• 37:44Speaker 02

  That a bonded workforce, happy workforce, was highly beneficial in terms of productivity. So they did things like building social clubs on every factory campus. And famously, the famous ones were the railway clubs. They started here in Britain, lots of railways before everybody else did. And every railway station had a railway club and everywhere in the empire that we built railways, there was a railway club. Everybody who worked at the station was automatically a member of the railway club. It's railway club. They would have social events and dancers and there would always be tennis courts because we're talking about the eighteen nineties up through to nineteen thirties maybe.

• 38:27Speaker 02

  Everybody played tennis, it kind of the fashion and everybody loved it. And I'm sure it had a lot to do with why some of these companies just set up. But I think what's happened sort of post the Second World War, the accountants are looking for ways of reducing costs and stuff. Those kind of social things have been thrown out of the window as, well, you can't put them in an income and expenditure ledger very easy. What does it mean? What's your output? How do you measure that? So we're not interested in it. We're just interested in the things that we can show in a an Excel sheet to have a direct effect on profit lines. And I think probably we might just consider taking a leaf out of their book again and going, well,

• 39:09Speaker 02

  what are the things people would like to do now? Because obviously life is different. You've got to sit back and think, well, what would work? What would attract people come in so that you provide them with the opportunity to meet in a casual social context, people from different parts of the company and build those kind of cross departmental links that allow the things to happen efficiently on the bigger scale, rather than just everybody getting into their silos within their own little department or group. And there are a number of cases where this has been done and done very successfully. It's not a case that nobody does it. Modern companies today are doing it very, very effectively. I gather with Facebook has a regular Wednesday

• 39:54Speaker 02

  beer and barbecue event in the sort of space in the centre of their campuses, as it were, where people just turn up and have a beer and burger and stuff and talk to people.

• 40:06Patrick O'Shaughnessy?

  Not that complicated.

• 40:07Speaker 02

  It's not complicated. And heaven forbid, you might even sign some nice person in finance that you get on really well with, instead of thinking of them as ogres. In our book, we give several examples. One was just founding a choir. And it's back to this magic of singing case where a government department set up a choir that they decided amongst themselves to do it. And eventually it changed the atmosphere within the department from a very, very frosty one, which was very fraught because of its history, into a very much bonded and efficient working group. Through, oh, just once a week, they sang in a, in a cell in our room somewhere.

• 40:50Speaker 02

  And eventually they ended up, a lot of them, competing in choir competitions and things like that. Or big brewing giants, SAB's, South African breweries, and bought Miller of Miller Lite fame, the American brewers. And they've since combined with A and B, the big Dutch, I think, brewing giants. Something like, I don't know, one in every eight beers poured anywhere in the world is brewed by them. Huge, huge company. But when they first started up, they had the idea of putting a, a little pub in the entrance foyer of all their factory buildings. So people just called in for a beer on their way home from work, you know, at the end of the day. And Sam, my co-author,

• 41:33Speaker 02

  who worked for them, twenty years on, some of the Facebook friendship groups that were set up from those casual beers afterward are still going, even though these people, most of these people no longer work for SAB Miller, are scattered all over the world. The friendships that were built up are still going strong. And of course, what's going to happen, sooner or later, in this big world of ours, you will bump into these same people somewhere else in another company. Or your company will be trying to make some arrangement with the company they work from. And oh, hello, good to see you again. Just makes everything go smoother.

• 42:11Patrick O'Shaughnessy?

  Can you explain the concept of homophily?

• 42:14Speaker 02

  This is the secret ingredient, really, of our friendship. So it was first discovered by sociologists about fifteen, twenty years ago. And they noticed that people tended to hang out with people who had very similar kinds of interests. So friends tended to have same political views, they tend to have same religious views, these kind of things. And since then, there's been more and more evidence, in fact, shed loads of evidence showing this effect is extremely strong. And we asked people to fill in big questionnaires about what they shared with their friends in terms of

• 42:54Speaker 02

  mofily and did some number crunching and it reduced it really to about seven key dimensions, which we called the seven pillars of friendship. So like a sort of supermarket barcode of who you are as a person, the community you essentially belong to. But it's what you speak rather than who you are biologically, if you like. It's the cultural elements that define you. It turns out that these have a very, very strong effect on the people we have in our layers. If you look at, feel closest to the people in your inner five shoulders to cry on friendship group, you will share six or seven of these dimensions with them. So there are things like sharing the same language, because they're rather crucial,

• 43:38Speaker 02

  because it's all about talking to each other. But also, where did you grow up? Where did you learn what it is to be a member of the community? What's your career trajectory been? What are your hobbies and interests? What are your moral and political and religious views? What is your preferred musical taste? What's your sense of humour? So the more of these boxes you tick with somebody, the closer in they will be in your inner circles. And the more intense and the longer those relationships will last. In addition to that, these are what you might think is the cultural component in the end is the much. But we share hermaphy with our friends on a lot of other fixed traits that we can't do anything about. So gender is a very, very strong one.

• 44:20Speaker 02

  Seventy-five percent of men's social circles, that hundred and fifty are males. Seventy-five percent of women's social circles are other women. Other twenty-five percent in each case is family. And I guess you don't have a lot of choice about that. Opposite sex, twenty five percent. But there's this very, very strong gender defect to social networks. Somehow feel more comfortable working around people of our own gender. Age has a very strong effect. All our friends and preferred family members that we give most time to tend to be around our age. Personality, again, introverts tend to prefer being friends with introverts. Extroverts tend to prefer to be friends with extroverts.

• 45:00Speaker 02

  And a lot of these really are about allowing you to come to compromises easily. Because the big problem is, just think of it in terms of extroverts and introverts. Saturday evening, you've got a choice. You can either go clubbing or you can stay in and watch a movie on the TV with a takeaway dinner. Two introverts that both want to stay in and watch it. This is nirvana, right? You've got two extroverts who want to go clubbing. This is another kind of nirvana. But the last option is you've got one of each. An introvert wants to stay and that extrovert who wants to go clubbing. And now you've got a problem. There's a negotiation that has to go on and somebody has to give way.

• 45:42Speaker 02

  Which means you've either got to sort of agree to alternate, in which case half the time you're bored silly. Because you'd rather be doing the other thing. But you're sacrificing yourself on the altar of love. But it's still stressing the relationship, stressing the friendship. So you can see very quickly that that applies to all these things. So this whole problem really, just engineering the smoothness and reducing the friction involved in relationships that are long lasting becomes very important. And you can see why homophily then becomes important. Because the more things you have in common, the fewer occasions you're going to disagree about what to do.

• 46:22Speaker 02

  The fewer occasions you are going to be left stranded and unable to think of anything to talk about. Which is a problem you have with a stranger. What do I say now? Well, with somebody who you were well gelled with, that's less likely to happen because you've got the same interests. But also you kind of don't mind if there are silent periods. You're happy to sit there together. So facilitating the kind of flow of the relationship becomes important. And at the end of the day, that feeds into the world of work. Because if two people get on. They're much more likely to work efficiently together to do each other favors than favors need to be done rather than saying, oh, come on, you know, we've got enough problems of trying

• 47:05Speaker 02

  to solve at our end of the business, you deal with yours. So homophily plays a very, very important role and it really strongly underpins our friendship. We just do for better or for worse. But at the end of the day, it does mean you end up in silos. So it's what pushes us to be in silos, neck of chambers is the problem. And that's the problem with scale, you know, in a small village, you don't have the freedom to go off and talk with the 50 people who are all interested in shooting ducks. There aren't that many people in the village who actually enjoy shooting ducks, just statistically. So you end up having to talk to people who like doing other activities. So you end up in a small business, a small organization or a small

• 47:49Speaker 02

  village, having a much more integrated, diverse, social life, if you like, social network. And the bigger life becomes, the bigger the city, the bigger the organization, the easier it is for silos to form, which is the big problem that large multinationals have, is they build up these us versus them internal structures. And the problem we have, both in everyday life, I guess, but also in particular in organizational structures in business and so on, is how to break those down. So you have to kind of think of ways of overcoming the homophily effect. Homophily is very good for certain things. Back to what I said earlier, if it's a small

• 48:32Speaker 02

  group with a focus on a specific task that needs to get done, then they all need to be homophylus, think the same way, know the same stuff, come from the same area. But you kind of don't want that probably on your management board, because you want some diversity of input up there. You've got to find ways of breaking down the homophyllous effect at the right level. Don't destroy it at the bottom, or you'll lose everything, right? It's important, it really is important. But at the same time, you need to be able to introduce diversity in the right levels and the right places. But it goes back, I think, to this point I made about the Japanese

• 49:13Speaker 02

  car industry, this sense of I belong to the company, I am a company man. It's creating this sense of Being a member of the village, I may be a very humble member of the village. All I do is sweep the yard outside, but I play my bit. So it's not easy and there are no silver bullets.

• 49:34Patrick O'Shaughnessy?

  I'm so fascinated that I think in your research, you show 60% of people's time they spend with maybe 40% with the closest five and another 20 with the next 10. Time, it just strikes me is the resource. It's the resource that we have to allocate thoughtfully and building those groups. Time is the only way to do it. Conversation and activity.

• 49:53Speaker 02

  Yeah, yeah. This has kind of implications for management because you can't create time. It is fixed. There is a limit and you have to do stuff like sleep. And the problem that most CEOs and the like, senior management get into is they end up trying to do too much and they don't have the time to do it. So they're trying to be engaging with everybody in a large company from the shop floor worker to the chief finance officer and so on. And you can't do it. And certainly you want to engage and be seen to be engaged with your workforce, not stuck away in some C suite at the top of the tower.

• 50:35Speaker 02

  But on the other hand, you've got to find some way of managing your time better. And what you don't want to be doing is wasting time on micromanagement. You have to be able to trust the layers below you, the management layers below you to do their job while you concentrate at the top of the pyramid on the kind of strategic stuff and seem to be the charismatic leader, if you like.

• 50:57Patrick O'Shaughnessy?

  Trust is so important. It's a word we haven't said much about, but so much of this is just establishment and maintenance of trust.

• 51:03Speaker 02

  Trust is what creates and maintains our relationships with each other. And when things fall apart, it's always because trust has broken down.

• 51:12Patrick O'Shaughnessy?

  I'd love to ask about a couple of big secular trends like inhumanity and how it affects all this. So the ones that come to mind are technology, the rise of all sorts of technology. We're talking not long after the Apple Vision Pro comes out, or there's always something new that seems important for how we spend our time. The second is the secular decline in religious beliefs. Maybe that's changing a little bit very recently, but over the long term, it's been in decline. And then the last one is the rise of psychological mental health problems, you know, unhappiness, mental disorders, et cetera. These seem like three important trends related to your ideas. You can pick one or all of them. And I'm just really curious to hear your reaction to those three big trends.

• 51:56Speaker 02

  They're all important and maybe they're all interrelated actually. But the last one that you mentioned in some ways is perhaps the most worrying one. And this is this tsunami of loneliness that sort of seems to have hit us. It was first noticed way back in the 90s, 30 years ago, started to show up. And a lot of this is basically young graduates going away to their first job in the big city. So up till then, your social world has been made for you by home, by university, college, halls of residence, these kinds of things. You don't have to sort of do much in the way of going out, finding. Then you go off your first job, the big city in New York or somewhere. And you don't know anybody, you don't know where to get to meet people.

• 52:40Speaker 02

  And especially you don't know where to go that's safe to meet people and to meet people with similar interests of yours to narrow it down even further. The only people you know are the people at work. And of course, five o'clock, they've all got things to do because they've already got social life. They've got families, you're stuck on your own. And this seems to have just got worse and worse and worse and triggered collapse into depression and indeed physical illness in the end. Because this is all related to the thing that I mentioned right at the beginning, the best predictor of your mental health and wellbeing and your physical health and wellbeing. Is the number of close friends you have and those close friends need to be there. It's no good having them at the end of a telephone line or a computer screen the other side of the country.

• 53:23Speaker 02

  They've got to be on the block with you so you can at least walk around, knock on the door and say, I feel like rubbish. Can you come out and at least have a coffee or something? Let's go for a walk in the park or something. You have to have that kind of physical contact. So this has been a big problem and I think the issue sort of in the process of overwhelming most organisations of businesses. They're losing huge quantities of time off work with people taking time off work. It's becoming more inefficient. It's putting much bigger loads on everybody else in the office, whatever it is, because they're now having to do not only their share of the work, but the share of the work that you're not able to do because you're all sick. So they're all getting very worried and investing huge quantities of money in sort of wellbeing.

• 54:08Speaker 02

  And the answer is it's expensive stuff. All you need to do is to find friends for people and you find friends for people by providing them with the opportunity, the place to go to meet. Because friendships are organic, you can't force people to be friends. All you can do is provide the opportunity and the space and hope that they they do it. But we're so intensely social, given the opportunity, we will do it. And you can do that very nearly for free. Just put on a choir for people to go and sing, they'll come. You don't need any money. You could even just put out some biscuits and coffee, a negligible amount compared to what you'd be paying for a sort of wellbeing trainer or something. So those sort of things are things we really have to look at.

• 54:53Speaker 02

  Now, in the past, I think a lot of those support networks would have been provided by religion. There's no question in my mind that that's really what the key benefit of religion has been for most societies. It doesn't really matter whether you believe it or not, it's the activities they do and the kind of context they provide. Because all the activities are just the sort of thing that kick in the endorphins system and make you feel good. And make you feel very bonded to the community, you know, hymn singing, lots of painful stories in the form of sermons and stuff that rouse your emotions. Kneeling and standing and occasionally stretching yourself out on the ground and all these kind of things that are part of this social toolkit. And of course, you don't have that.

• 55:37Speaker 02

  You're losing somewhat of the skeleton that has kept communities together in the past. The problem is, religion is strange stuff. So you might well think that the world is better off without religions because they have this dreadful tendency to end up fighting each other. The great problem is, nothing comes for free in life or biology. And the thing is, there's no such place as Nirvana. There's a downside to everything. So you have to balance the upsides and the downsides of these things. And in some sense, I suppose, the internet then has become a little bit of a substitute in a way. And it is very weird stuff, but it is compelling. Go online to look something up. You just want a tiny bit of information for something you're doing.

• 56:22Speaker 02

  If something else turns up in the feed, you know, that looks interesting. Oh, there's a video there, my favorite pop song from forty years ago. I just must look at that. And you end up spending the whole evening online. It's very, very engaging. And it probably does trigger a certain sort of bonding. My worry with it, though, is that you're bonding with something in your head, not with something in the real world. And the problem here is precisely that in real life, you might start off in real life by being introduced to somebody by a friend or a relative or something. Which is how we used to meet most people. But you would be able to get to know them face to face.

• 57:04Speaker 02

  And so you'd have a kind of ground truthing that went on where you would kind of evaluate, despite all the things they say, is it really true? Does it mean it? We get a lot of cues from people's facial expressions on how honest they're being. Of course, what happens on dating scams or any other financial scams, any of these things, is they're very careful not to meet up. They're very careful not to meet up online visually and video. So you can't see what they actually look like. You can't see what the cues of trustworthiness on their faces like when they're talking to you. So what you're doing is you're building a kind of avatar in your mind. Now, this is what we do anyway, when we create a friendship, when we create a romantic relationship.

• 57:48Speaker 02

  What we initially do is build an avatar in our heads as to who this wonderful person is. But meeting them face to face allows you to sort of knock the rough edges off a little bit and get to know their inner core better. And that's the danger of the internet, I think, is that it just lacks this capacity to be able to sit across the table in a pub or a cafe or a restaurant and stare into the whites of the other person's eyes and reach across the table and pat them on the shoulder or something that gives you this sense of who they really are and how honest they really are. So I've often said, you want to know how much somebody actually feels about you, friend or romantic partner, whatever it may be, a family member, doesn't matter,

• 58:33Speaker 02

  how they really feel about you. Ignore everything they say because words are weasely things and we can misuse them and misunderstand them. Just check how they touch you because that is actually the best. A touch is worth a thousand words any day in this context. You can't lie about how you touch somebody and we're very, very good at recognizing when a touch is meaningful and when it's false.

• 59:00Patrick O'Shaughnessy?

  If you think about everything you've studied across your life so much, you've been a prolific writer and researcher. If you set aside the social brain research and homophily and things like that, what idea or ideas do you find the most energizing or interesting across your whole career of study?

• 59:19Speaker 02

  It's actually time. In many ways, time was the beginning of all this stuff. Having worked on monkeys and antelope in Africa and Europe in the wild, you begin to realize that what's limiting for animals is not necessarily food. In fact, ecologists tend to look at the way the world works in terms of food availability. So population die out because there isn't enough food. In the extreme case, that's probably true, but we're talking about the demise of the dinosaurs when everybody dies because everything's been destroyed by some comet coming in or everything's got polluted. So there's no oxygen in the seas,

• 1:00:02Speaker 02

  whatever it may be. In the normal course of things, it's not food that really limits them. No matter how bad your quality of your food is, the vegetation order may be, if you had infinite time, you could get all the food you needed. What you don't have is infinite time. You have to get the food you need to keep yourself alive. In within a certain period of time, that's usually a day, obviously. So you've got to keep eating. Small birds and mammals literally keel over and die if they don't eat their body weight in food a day, particularly in cold climates in the winter. So it's really time that's the problem they have. And that got expanded from the world of animals. There's all sorts of implications for things like conservation and stuff as well.

• 1:00:47Speaker 02

  It was the starting point of looking at humans and going, actually, we don't have infinite time. A lot of the things we do are attempts to cut through time constraints.

• 1:00:58Patrick O'Shaughnessy?

  Fascinating application of the ideas. Robin, thanks for doing this. I've so appreciated everything you've written and sharing so much with us today. I learned so much. Thank you so much for your time.

• 1:01:09Patrick O'Shaughnessy?

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