Robin Dunbar: the synopsis episode on BEYONDai

The full account lives here: Robin Dunbar: The Science of Friendship, Dunbar's Number & the 150 | The BEYOND Podcast

Friendship runs on hard, measurable constraints rather than sentiment: Dunbar's number, the roughly 150-person limit, resolves into nested emotional layers (5, 15, 50, 150, then 500 and 1500), each demanding a fixed time investment of about 200 hours of face-to-face contact to make a close friend, while cultural similarity (the seven pillars of friendship), trust and shared bonding behaviors (the social toolkit, above all singing) decide who we keep.

Our synopsis episode on BEYONDai takes Robin Dunbar's conversation and produces it into a single cut, entity by entity: the thesis stated, and every subject given its own point of view. This is what the episode knits together.

"Um, but you just don't have time, 'cause you're meeting all these other new people."Robin Dunbar

What the episode knits together

Robin Dunbar, evolutionary psychologist and author of Friends: Understanding the Power of our Most Important Relationships

The episode threads through the conversation, so anyone researching Robin Dunbar meets it in the primary source rather than a summary of it.

Friends: Understanding the Power of our Most Important Relationships

The episode threads through the conversation, so anyone researching Friends: Understanding the Power of our Most Important Relationships meets it in the primary source rather than a summary of it.

Dunbar's number

The episode threads through the conversation, so anyone researching Dunbar's number meets it in the primary source rather than a summary of it.

Watch or listen to the source conversation: Robin Dunbar podcast · Robin Dunbar episode on Apple Podcasts · Robin Dunbar episode on Spotify · Robin Dunbar episode on Amazon Music. It was recorded on The BEYOND Podcast with Aleksandra King.

Episode highlights transcript

Introduction

Guide: Welcome to the BEYONDai Podcast, a series that highlights the best thought leadership, from the best guests on the best shows. This episode features Robin Dunbar speaking with Aleksandra King on The BEYOND Podcast.

And- and coworkers in here

Robin Dunbar: Well, the official limit on the number of friends and family, I

Robin Dunbar: hasten to add, um, uh, that you can have is 150 people, which is Dunbar's number.

Robin Dunbar: So that's your extended family and all your friends.

Robin Dunbar: Uh, yeah, it ... The o- one way to think about it is all the people who at least

Robin Dunbar: once a year you try to keep contact with.

Robin Dunbar: In the old days when people sent Christmas cards, it was exactly

Robin Dunbar: who you sent Christmas cards to.

Robin Dunbar: So if you tot it up, everybody in the family that you sent a card

Robin Dunbar: to, it comes out to about 150.

Aleksandra King: 150 still seems like quite a lot if you- if you're count- so

Aleksandra King: you're counting friends and family- And family ... and- and coworkers in here?

Robin Dunbar: Oh, c- coworkers can be friends.

Robin Dunbar: I mean, that's the difference.

Robin Dunbar: But it ... Out beyond f- uh, 150 is another layer that we

Robin Dunbar: think of as acquaintances.

Robin Dunbar: Okay.

Robin Dunbar: And so a lot of the people you work with would be in that sphere, as it were.

Robin Dunbar: But some of the people you work with become friends because you get on well

Robin Dunbar: with them, you see them after work.

Aleksandra King: Okay, so when people have, like, 300-plus friends

Aleksandra King: on Facebook, that's not true?

Robin Dunbar: Um, well, it's not true anyway.

Robin Dunbar: Uh, uh, for two reasons.

Faces you can put names to basically

Robin Dunbar: But really what they're including is acquaintances.

Robin Dunbar: So acquaintances is people, we go and have a beer with them after work,

Robin Dunbar: but we would never invite them home.

Robin Dunbar: That's the big difference.

Robin Dunbar: Hmm.

Robin Dunbar: 150 you would invite home.

Aleksandra King: Could acquaintance be someone you've

Aleksandra King: come across, just someone that-

Robin Dunbar: Yes, it be- ... you know, "Oh, yes,

Aleksandra King: I know you.

Aleksandra King: Yes.

Aleksandra King: Friend."

Robin Dunbar: But it, I think acquaintance is a bit more than

Robin Dunbar: just a, "I met you once at a party and- and- and we- Just be friends

Robin Dunbar: exchanged phone numbers." Yeah.

Robin Dunbar: That you actually see- see them on a regular basis, and you would go out and

Robin Dunbar: do something occasionally with them, even if it's only going have a, have a beer.

Robin Dunbar: Um, because beyond the f- the ... So- so the acquaintances layer runs out to about

Robin Dunbar: 500 people, and then beyond that is one more layer which includes people whose-

Robin Dunbar: Faces you can put names to basically.

Robin Dunbar: So they-

Aleksandra King: Sometimes.

Aleksandra King: Sometimes.

Robin Dunbar: Well, no, that- Or- Anybody else that's beyond that level- No, right

Robin Dunbar: you can't put a face, name to the face.

Robin Dunbar: Depends on

Aleksandra King: one's memory.

Robin Dunbar: Yeah.

Robin Dunbar: Well, it, it, you know- Yeah ... I mean, these, these things have a

Robin Dunbar: range of variation, so, you know, okay, the average si- number of

Robin Dunbar: friends and family that people have is 150, but the range of variation is

Robin Dunbar: probably from about 100 to about 250.

You see this most clearly demonstrated in romantic relationships

Robin Dunbar: In fact-

Aleksandra King: Gosh

Robin Dunbar: to get somebody to, who is, uh, outside your 150, so somebody

Robin Dunbar: you've, you've basically just met, a stranger, into at least your 15

Robin Dunbar: layer, your regular sort of social-

Aleksandra King: Yes

Robin Dunbar: little clique- Yeah ... takes about 200

Robin Dunbar: hours of face-to-face contact.

Robin Dunbar: Oh.

Robin Dunbar: All right?

Robin Dunbar: It's hard work.

Robin Dunbar: And that's partly- That is hard work ... because you've also got to drop somebody.

Robin Dunbar: 200

Aleksandra King: hours.

Robin Dunbar: You've got to drop somebody.

Robin Dunbar: If you wanna bring somebody else in, somebody's got to fall out of

Aleksandra King: your circle.

Robin Dunbar: Oh, brutal.

Robin Dunbar: Right?

Robin Dunbar: And you see this most clearly demonstrated in romantic relationships

Robin Dunbar: because, for obvious reasons, not many of us fall in love with the people in

Robin Dunbar: our inner, innermost circle, right?

Robin Dunbar: Yeah.

Robin Dunbar: They come in from way outside- Yeah ... the solar system.

Robin Dunbar: Usually they're strangers.

Robin Dunbar: But very often intro- we're introduced to them by a member

Robin Dunbar: of our- Yes ... extended circles.

Robin Dunbar: So that you bring them right into the center, and you've now

Robin Dunbar: got six people- Instead of five

Aleksandra King: Too much

Robin Dunbar: But this person is taking, because of the nature of the

Robin Dunbar: relationship, is taking up twice as much time, so they're taking up two units.

Robin Dunbar: So you've actually got f- seven, seven units of person time, uh,

Robin Dunbar: where you should only have five.

Robin Dunbar: And what do you do?

Robin Dunbar: You drop two people.

Robin Dunbar: So you reduce- That's so brutal ... the size of that circle to four.

Robin Dunbar: And what you usually do is drop a family member and a friend, right?

We're very prone to following people who appear charismatic

Aleksandra King: Yes.

Robin Dunbar: But by and large, they're successful- As bullies rather than as-

Aleksandra King: Yeah

Robin Dunbar: people managers.

Aleksandra King: So what's the difference between that?

Aleksandra King: Someone who's genuinely, let's say, the exotic, confident, doesn't mean badly to

Aleksandra King: anyone, is just by nature such a person, and then the one that is maliciously

Aleksandra King: Well, I don't know if you know the difference.

Aleksandra King: Maybe they're not trying to be malicious, but maybe they just are a bit

Aleksandra King: What, what is that thing that is so

Robin Dunbar: horrible?

Robin Dunbar: It, it's charismatic leadership, actually, is what it boils down to.

Robin Dunbar: And we're very prone to following people who appear charismatic

Robin Dunbar: and appear to have gifts-

Aleksandra King: Mm

Robin Dunbar: that are greater than the ones we have, that they make good

Robin Dunbar: leaders, uh, to follow, you know.

Robin Dunbar: And we do it all the time.

Robin Dunbar: Pop stars, celebrities, you know, uh- Mm ... people who invent stuff and become,

Robin Dunbar: you know, CEOs and- Yes ... charismatic CEOs of, of a, of a big organization.

Robin Dunbar: Um, and, and that kind of has a place in our social world because-

Robin Dunbar: In the end, social world is about cooperation and diplomacy, but you

Robin Dunbar: can't have sort of 500 braves- Mm

Robin Dunbar: in the organization.

Is about handling three mind states

Aleksandra King: Incredible.

Robin Dunbar: Right?

Robin Dunbar: But if they're talking about somebody's mind state, Hamlet, who's not there,

Robin Dunbar: so it's Hamlet's friends talking about his, Hamlet's mind state, um, and he's

Robin Dunbar: doing whatever he was doing somewhere else, he reduces the number to three.

Robin Dunbar: And what he's doing is making sure he doesn't overload his audience's abilities.

Robin Dunbar: Yeah.

Robin Dunbar: Right?

Robin Dunbar: But-

Aleksandra King: That is smart.

Aleksandra King: Smart ... so Wow.

Robin Dunbar: Three, the, the, the, the pe- pe- pe- normal human adults, there's

Robin Dunbar: nothing unusual about them, as it were, psychologically, uh, the, the lower limit

Robin Dunbar: is about handling three mind states.

Robin Dunbar: And that's perfectly fine.

Robin Dunbar: You can get by in the social world and conversations and all these

Robin Dunbar: things quite happily with, with third order mentalizing, as it's called.

Robin Dunbar: But it does mean that a fifth order mentalizing story just

Robin Dunbar: becomes incomprehensible to you.

Robin Dunbar: Overwhelming.

Robin Dunbar: So you like stories which involve only a couple of people's mind states.

Robin Dunbar: And this applies to our sense preferences for humor as well.

This all hinges around how you define gossip

Robin Dunbar: Um, in fact, they'd rather have a slightly bigger share than you.

Robin Dunbar: Uh, whereas, well- Yeah

Robin Dunbar: I was gonna say your dog dog will let you have half, but

Robin Dunbar: actually he probably wouldn't.

Aleksandra King: No.

Aleksandra King: Yeah.

Robin Dunbar: But anyway It's

Aleksandra King: fair enough.

Aleksandra King: It's fair enough.

Aleksandra King: You know,

Robin Dunbar: it's-

Aleksandra King: But you'd happily let them have that.

Aleksandra King: Yeah.

Aleksandra King: That's the thing- Yes, you would ... you sacrifice yourself,

Aleksandra King: wouldn't you- Yeah ... for your pet?

Robin Dunbar: Yeah.

Aleksandra King: Your friend, mm.

Robin Dunbar: Yeah.

Robin Dunbar: And I think that's- Not so

Aleksandra King: much

Robin Dunbar: not uncommon.

Aleksandra King: Yeah.

Robin Dunbar: You know, that, that people have very close attachments.

Aleksandra King: I was happy- Yeah ... actually to see the posts

Aleksandra King: on Facebook 'cause I thought, "Oh."

Robin Dunbar: Yeah.

Aleksandra King: It's like me." Yeah.

Aleksandra King: So I wanted to ask you about, there's something I read on your

Aleksandra King: LinkedIn, um, which is about gossip.

Aleksandra King: Yes.

Aleksandra King: And that that's a really lovely, good thing.

Aleksandra King: Why would you say something like that?

Aleksandra King: Because gossip, gossip for me, I do find sometimes when I go into these circles

Aleksandra King: and, you know, chatting... And, and it tends to be actually a lot, a lot of the

Aleksandra King: time, you know, the sort of the, the, the mum with the kids crowds- Yeah, yeah

Aleksandra King: and, and then the gossip starts.

Aleksandra King: Yes.

Aleksandra King: And there's someone being sold- Yeah ... at all times.

Aleksandra King: Yeah.

Aleksandra King: You know, and it, I, always.

Aleksandra King: Why?

Robin Dunbar: Well, well, this all hinges around how you define gossip.

Aleksandra King: Okay.

Robin Dunbar: All right?

Robin Dunbar: So that kind of horrid sense of gossip, right, wicked sense of

Robin Dunbar: gossip, is actually relatively recent.

A terribly important role

Robin Dunbar: So there is a sense in which gossip, this positive sense of gossip, plays

Robin Dunbar: an important role in managing our relationships because you, by definition,

Robin Dunbar: cannot possibly know everything that's happened 24 hours a day to all your

Robin Dunbar: 150... You know, you can't even do it for your, probably your romantic

Robin Dunbar: partner as the one closest- Yeah

Robin Dunbar: the person in n- position number one, um, because some of the time

Robin Dunbar: they're, they're elsewhere, right?

Robin Dunbar: So what we rely on is a chain of information flow, i.e. gossip, through

Robin Dunbar: the network created by our 150s.

Robin Dunbar: You know?

Robin Dunbar: And you see this particularly with families.

Robin Dunbar: So in, in, in family contexts, there's a per- al- almost always

Robin Dunbar: a person called a, a kin keeper.

Aleksandra King: Okay.

Robin Dunbar: Usu- usually female because they do it best, but

Robin Dunbar: what, but what their role is is to keep everybody up to date on how

Robin Dunbar: everybody's doing, how little Jemima's- Uh-oh ... new baby is getting on.

Aleksandra King: I might be guilty- You know?

Aleksandra King: of that as

Robin Dunbar: well.

Robin Dunbar: But they play a- Yeah, but ... a terribly important role.

Robin Dunbar: They play,

Aleksandra King: they really do.

Aleksandra King: Yeah, I feel like it's my duty- Right, yeah ... to say to, you

Aleksandra King: know, so and so this has happened.

Aleksandra King: Yeah.

Aleksandra King: So but,

Robin Dunbar: you know.

Robin Dunbar: Yeah.

Robin Dunbar: A- and you're, you, in some sense, family networks are better than friendship

Robin Dunbar: networks in this point of view-

Aleksandra King: Mm

Robin Dunbar: because there are so many interconnections.

Robin Dunbar: It's like a spider's web, so you can get information.

Robin Dunbar: If Jemima doesn't tell you- Yeah ... Penelope will, you know?

Aleksandra King: Information transfer.

Robin Dunbar: Yes.

Robin Dunbar: It's all about information transfer.

Robin Dunbar: Now, that helps us keep up to date with how things, therefore you don't make

Robin Dunbar: faux pas when you bump into somebody and, you know, you say, you know,

Robin Dunbar: I don't know, m- m- maybe they just got married or something like that.

What then makes people wanna push others away

Aleksandra King: Okay

Robin Dunbar: things won't happen.

Robin Dunbar: Yeah.

Robin Dunbar: People will just drift away, and, and it, y- you know, any, any group that tries

Robin Dunbar: to be democratic in that sense that's bigger than 50 simply doesn't survive.

Robin Dunbar: Yeah.

Robin Dunbar: It just-

Aleksandra King: You, you need a strong leader to manage- Yeah

Aleksandra King: a big group and, and... Okay, so what then makes people wanna push others away?

Aleksandra King: Because you've got that thing too where you think, "Oh- No.

Aleksandra King: What, what's that all about?

Robin Dunbar: Oh, I think it's, I think it's just basically the fact that

Robin Dunbar: you don't connect with them, right?

Robin Dunbar: Mm-hmm.

Robin Dunbar: You've got nothing in common with them.

Robin Dunbar: So all these things that, um, create this homophily effect, both, both are

Robin Dunbar: biological and, and, and psychological traits, but also these cultural traits,

Robin Dunbar: the seven pillars of friendship.

Robin Dunbar: You know, at the end of the day, if you don't have enough connection with people,

Robin Dunbar: the relationship won't last, right?

Robin Dunbar: Mm-hmm.

Robin Dunbar: So this is, you know, the classic case is, you know, I don't know, you're, you,

Robin Dunbar: you, you're there at, in the bar at, uh, at Ibiza or some seaside place, and it's

Robin Dunbar: 4:00 in the morning and there's only one other person in the bar, you know?

Robin Dunbar: Yeah.

Robin Dunbar: And it turns out you both happen to be, uh, enthusiasts for tiddlywinks, right?

Confidence to handle weaker relationships

Robin Dunbar: It's a, it's a-

Aleksandra King: I never thought

Robin Dunbar: about it like this- ... two-way process ... but it's

Aleksandra King: an investment.

Aleksandra King: Yes.

Aleksandra King: Gosh.

Aleksandra King: Yeah.

Robin Dunbar: Um, now, what, what seems to happen is introverts take a kind of

Robin Dunbar: risk averse, so they really want to be sure that w- when disaster happens, and

Robin Dunbar: the problem is you can't legislate for it.

Robin Dunbar: You, you know, it, it's too late, uh, to go and ask somebody to help you

Robin Dunbar: out in, in, in those sort of- Yeah

Robin Dunbar: states of affairs, as it were, um, if you don't already have

Robin Dunbar: a relationship with them.

Robin Dunbar: You have to have set that up ahead of time, well ahead of time

Robin Dunbar: for them to be willing to do it.

Robin Dunbar: So the- what they want to be sure is that the people they have in that

Robin Dunbar: little group w- really will do the job.

Robin Dunbar: So they'd rather have fewer of them and invest more time in each one, and

Robin Dunbar: that means they have smaller networks.

Robin Dunbar: Whereas extroverts seem to trade on their social, um, skills, as it were, and social

Robin Dunbar: confidence to handle weaker relationships.

Robin Dunbar: So their view is, "Well, you know, if Jemima turns me down and won't help,

Robin Dunbar: I'll go and ask Philomena," you know?

Aleksandra King: Mm.

Robin Dunbar: Because somebody will do it.

Aleksandra King: Somebody, which, but you

Robin Dunbar: know that- And then they, then they can, then what they have- Yeah

Robin Dunbar: is more friendships, so their social, social networks are bigger than 150,

Robin Dunbar: but the average re- emotional closeness is much weaker than introverts.

Because each relationship require, has its own time demand

Robin Dunbar: Time is fixed.

Robin Dunbar: Yes.

Robin Dunbar: You know, you can't, you can't, uh- No more time ... create time,

Robin Dunbar: um, uh, because each relationship require, has its own time demand,

Robin Dunbar: depending on the emotional closeness.

Robin Dunbar: Which layer that they're a ... That dictates how much time you have to invest.

Robin Dunbar: Because if you don't invest that time, that relationship will decay inexorably.

Aleksandra King: Yes.

Robin Dunbar: Uh, it takes about two years of not seeing a person for them to

Robin Dunbar: move from, say, your 15 layer, so a good regular social friend, to become just

Robin Dunbar: an acquaintance, somebody I once knew.

Robin Dunbar: Oh.

Robin Dunbar: Right?

Aleksandra King: That's frightening.

Aleksandra King: That is

Robin Dunbar: frightening.

Robin Dunbar: That's if you don't see them at all.

Aleksandra King: Yeah.

Robin Dunbar: Right?

Robin Dunbar: Which is what tends to happen.

Robin Dunbar: You know, if you think about your experience, you, you went

Robin Dunbar: away to university somewhere.

Robin Dunbar: You had this little group of people you did stuff with, and then

Robin Dunbar: you all parted company and went different parts of the world, right?

Robin Dunbar: And some of them, you tried, made a big effort to keep up with, and

Robin Dunbar: they tended to be this, the one or two platonic close friends.

Robin Dunbar: But the others, you kind of feel very guilty about not keeping up with.

Robin Dunbar: Um, but you just don't have time, 'cause you're meeting all these other new people.

Close

Guide: That was Robin Dunbar speaking with Aleksandra King on The BEYOND Podcast. Visit BEYONDai.media to learn more. See you on the next episode.

Read the full account: Robin Dunbar: The Science of Friendship, Dunbar's Number & the 150 | The BEYOND Podcast

Narration is AI-generated. Everything said in the conversation is human.