How Evolution Shaped Our Societies | Professor Nicholas Christakis

1. 0:00 – 5:01

   Intro

   1. NCNicholas Christakis0:00

      You're born today and you inherit all this stuff that everyone before you, all the domesticated animals. Other people domesticated these animals-

   2. CWChris Williamson0:08

      (laughs) Yeah.

   3. NCNicholas Christakis0:08

      ... thousands of years ago. Uh, uh, all the domesticated plants, all the roads which were built in England starting with the Romans-

   4. CWChris Williamson0:15

      Yup.

   5. NCNicholas Christakis0:15

      ... calculus, which was invented by Newton 500 years ago, it's yours for free.

   6. CWChris Williamson0:21

      (laughs)

   7. NCNicholas Christakis0:21

      All of this stuff. How to smelt iron, you know, all the knowledge about iron and fishing, how to ... Fish hooks, I talk about fish hooks in the book, like the invention of fish hooks. The wheel, you g- ... Fire, you go on and on and on. All of this stuff, which was just given to you when you were born, was cumulated by other humans across time, and, um, and it's this that makes us so powerful a species. 'Cause we have, if you think about it, rather pathetic bodies.

   8. CWChris Williamson0:46

      Yeah.

   9. NCNicholas Christakis0:46

      I mean, it's not our bodies that are, are making us powerful on this planet. It's our culture, our brains that are-

   10. CWChris Williamson0:52

       Yeah.

   11. NCNicholas Christakis0:52

       ... making us powerful.

   12. CWChris Williamson0:57

       I am joined by Yale professor, author, and incredibly wise human, Nicholas Christakis. Professor Christakis, welcome to the show.

   13. NCNicholas Christakis1:06

       Thank you so much for having me.

   14. CWChris Williamson1:08

       I'm, uh, I'm very excited to sit down with you. I really enjoyed you on Joe Rogan about six weeks ago. Uh, fell in love with the content that you guys put out, and, uh, yeah, I've been looking forward to speaking with you ever since. So, what are we gonna learn about today?

   15. NCNicholas Christakis1:23

       Well, um, I think the topic that I've been thinking about lately is human nature, and the part of human nature that interests me is not so much that part that we express within ourselves. So for example, you know, you, you could, uh, be spiritual within yourself, or you could be risk-averse within yourself, or you could be, uh, uh, you could have wanderlust within yourself. These are qualities that, uh, human beings the world over might or might not express, and that have been shaped by our evolution and by natural selection. The parts that I'm interested in are the parts that, of our human nature that we express between ourselves. For example, do we love each other? Do we befriend each other? Do we cooperate with each other? Do we teach each other things? These are things that we also are naturally inclined to do, um, and those are parts of our nature that we express between ourselves. And the reason I, I think these are important is that for too long, in my view, scientists and, um, sort of people on the street, the citizen- citizenry, have been overly concerned with what I would regard to be the dark side of our nature, our propensity to, to, to violence and, uh, tribalism and, and lying and, uh, you know, um, selfishness. But the bright side, I think, has been denied the attention it deserves, because equally, we are prone to all those things I mentioned, to love and kindness and friendship and so forth, and in fact, I would argue that those forces were necessarily more powerful than the, uh, than the evil forces. So-

   16. CWChris Williamson2:50

       If they, if they weren't, we wouldn't have made it very far.

   17. NCNicholas Christakis2:53

       Yeah, well, that ... Well, yes, but more to the point, we wouldn't be living socially. If every time I came near you, you killed me-

   18. CWChris Williamson2:59

       (laughs)

   19. NCNicholas Christakis2:59

       ... or, uh, or, or, or gave me false, useless information-

   20. CWChris Williamson3:03

       Yeah.

   21. NCNicholas Christakis3:03

       ... or took advantage of me in some way, I would be better off living as a solitary animal. So, so the, so it must be the case that the benefits of a connected life outweigh the costs. Otherwise, we wouldn't be, we wouldn't be living socially. Um, and so that's what I've been interested or thinking about lately. How and why, how and why did, did our evolution not just shape the structure and function of our bodies, you know, how our kidneys work, or our pancreas works, not j- ... Or our muscles work, not just shape the structure and function of our minds, you know, how we think, uh, how we cope with adversity, uh, how we, um, how we, uh, you know, how we, uh, our personalities, for example, but how, as well, s- uh

   22. NANarrator3:47

       (...)

   23. NCNicholas Christakis3:48

       ... shaped the structure and function of our societies? H- how did we come to live socially the way we do? Is it the case that the way we live, the societies we make, the world over, actually have been guided by our long evolutionary past? And, and I, the answer is yes.

   24. CWChris Williamson4:03

       Thinking to a lot of the conversations that I've been having recently and a lot of the books that I lean towards, and I know that a lot of the audience will do as well, I certainly think that there is, uh, I, I'm discriminating towards the individual on those books. A lot of things to do with-

   25. NCNicholas Christakis4:19

       Uh-huh.

   26. CWChris Williamson4:20

       ... understanding our nature. Recently had Robert Greene on, The Laws of Human Nature. Recently had, uh-

   27. NCNicholas Christakis4:26

       And what qualities, what qualities did he emphasize about human nature, for example?

   28. CWChris Williamson4:30

       Oh, wow. Um, so he talked about the fact that if you have brilliance in the world, you can be as talented as you want, but without the ability to understand others and communicate effectively-

   29. NCNicholas Christakis4:42

       Uh-huh.

   30. CWChris Williamson4:43

       ... you will neutralize your brilliance and live a p- a, a life filled with pain and misery. That was his synopsis.
2. 5:01 – 7:07

   Talking in a Positive Light

   1. CWChris Williamson5:01

      You've also touched on the fact that talking in a positive light is something which appears to be lacking, a little bit. And I would agree, I'd definitely agree on both counts. I think a lot about the fact that social media posts that anger people or agree with what they believe are the two most highly engaged posts on the internet. Presumably, that's going to lead to authors and ... It will trickle either up or down, however (laughs) you wanna call it, to academics, to also think, "Well, if I want to write a book or have a paper or a study which is going to be, uh, highly recognized and, and interesting," at the moment, it would appear that trying to maybe focus towards the darker side of human nature, the things that are bad, the things that maybe anger people, et cetera, maybe that's, uh, a bias. I'm not sure whether you think that's the case.

   2. NCNicholas Christakis5:54

      Well, I mean, okay, so, uh, I mean, we have a number of biases. I mean, thi- this attention to bad news is something which m- many people are thinking about. Like, why ... I- if that's part of what you're talking about is why do we, why do we focus on the nasty things that are around us so much, part of the reason is that...... it is more advantageous to you to pay rapid attention to bad things, people theorize, than to pay rapid attention to good things. So for example, in our ancestral environment, it would have been more beneficial to you to pay attention to the location of a fire, or a flood, or predators, for example, than to... which is all bad news, than to pay attention to the location of food, for example, which would be good news. Because one of them is going to kill you fast, and, uh, the other one, you know, might take a while, the absence of good news, let's say. So, so this is one of the reasons that it is thought that we humans are wired to preferentially attend to bad news. And you know why, why media constantly, you know, fe-feature stories of, you know, misery and destruction, and people click on it and read it. So, um, anyway, so that's part of it, I think, what, what is going on. But there was another part to your question. I, I lost track

3. 7:07 – 11:06

   Focus on the Individual

   1. NCNicholas Christakis7:07

      of the other part.

   2. CWChris Williamson7:08

      So part of it is the anger and the leaning towards negativity, and the other part is the focus on the individual rather than the group. I think we're in-

   3. NCNicholas Christakis7:16

      Yes.

   4. CWChris Williamson7:17

      ... the meritocracy that we're in at the moment, with the Gary V hustle and grind, uh, culture that we have going says that your successes and failures are yours to hold on your own. And I think that that leads people to look inwards towards, "How can I make myself better?"

   5. NCNicholas Christakis7:33

      Yes.

   6. CWChris Williamson7:34

      Um, and not necessarily maybe think about the group.

   7. NCNicholas Christakis7:38

      Yes. Uh, I take your point. I mean, a lot of these qualities th- we have to distinguish between those aspects of the point you just made that relate to... that are culturally specific, you know, that have to do with the society we're raised in, or that are individually specific, the kind of person you are, from those qualities that have been shaped by the long arc of our, our, uh, natural selection. And, um, and so, uh, I, I guess what I would say is, is that while it is the case that there's a lot in our nature that makes us pay attention to our individuality and how we act... In fact, I'm gonna come back to this point in a moment. Uh, much more interesting to me, and much more relevant to our survival, is our capacity to work together. But let me, let me say two things about this. First of all, this notion that we're individuals, which you take for... which many people take for granted, actually is a kind of an interesting aspect of our species. So it is... If you think about it, every, every... you know, we, we humans are capable of being individuals, and not only are we conscious about it, but we, we signal our unique identity. And we humans do that with our faces. So our faces, every human face is, is different. While in principle every pancreas should work the same, every face should not look the same. Every face should look different. And those regions of our genome that are responsible for the faces we're born with, those regions are highly variable and highly recombinable in ways that explain, in large measure, the great variety of human faces. But not only do we signal our individual identity, not only do each of us have the capacity to say, "This is me, not you or not someone else," but each of us is capable of detecting other people's individuality. Our brain has regions that are devoted, a lot of energy and brain space is devoted to the ability to tell the difference between people. You can look out at a sea of 1000 people in a nightclub, for example, and you can tell each person is different, who is who on the dance floor. And this is important, so you go and you dance with your own partner and not some random person on the-

   8. CWChris Williamson9:45

      (laughs) Yeah, that would be-

   9. NCNicholas Christakis9:45

      ... on the partner-

   10. CWChris Williamson9:46

       ... that would be a bad idea.

   11. NCNicholas Christakis9:47

       Yeah, and it would be awkward. And, and you want to reciprocate, you know, like, you know, this person kissed you, and now it's time to kiss them back, not a different person back, for example.

   12. CWChris Williamson9:55

       (laughs)

   13. NCNicholas Christakis9:56

       So but t- to do that, but to do that, you need to be able to tell who is who. And so this, all of this machinery, the face that signals identity, the brain power that detects identity, all of this is an evolutionary luxury. Other animals don't do this. We do this. And one of the deep paradoxes about living socially as a mammal is that first we must be individuals. This, the- there's a lot of, uh, capacity that, uh, that, that we have that makes us capable of si- being individuals and signaling our identity, which actually allows at the... uh, lies at the foundation of our ability to live socially. So, so for example, this relates to our ability to be friends. How, how can you have friends with other people unless you can track who is who? In order to have a sustained relationship with Tom and not Dick or Harry, you have to be able to reliably tell, "This is Tom, not Dick or Harry, and this is Tom yesterday, and now this is still Tom." So, so this, this, this capacity to be individuals is very deeply connected to our capacity, uh, to live socially. So, um... Now I forgot how I went off on this tangent

4. 11:06 – 13:21

   Other Animals

   1. NCNicholas Christakis11:06

      you asked me about, uh-

   2. CWChris Williamson11:06

      Um, I wanted, I wanted to ask there, so you've touched on the fact that other animals don't do this?

   3. NCNicholas Christakis11:10

      Uh, right.

   4. CWChris Williamson11:11

      What do you mean don't do this, and how so?

   5. NCNicholas Christakis11:15

      Well, have you ever, ever looked at a sea of penguins and, or cows? I mean, I guess farmers can sometimes tell their cows apart, but, you know, a cow is a cow. I mean, there's a herd of cattle and-

   6. CWChris Williamson11:25

      Is that-

   7. NCNicholas Christakis11:25

      ... you don't have any sense-

   8. CWChris Williamson11:26

      Is, is that our interpretation of the cow, or is... Presumably the cows must be able to tell each other apart.

   9. NCNicholas Christakis11:33

      Not as unique individuals. They can tell their offspring. So for example, cows can tell, "This is my calf, I should mil- feed milk to this calf, not anyone else," but they don't tell, as far as we know, the difference between strange cows individually. Here are 100 strange cows. Oh, but this is this strange cow, and this is that strange cow.

   10. CWChris Williamson11:51

       Ah.

   11. NCNicholas Christakis11:51

       Elephants do it. Now we're not the, we're not the only animal that does it, to be clear. Other social mammals do this. Uh, so we do it. We have this capacity for individuality. Uh, uh, certain other primates do it. Uh, elephants do it, both African and Asian elephants. Certain cetaceans do it. There's very interesting evidence from dolphins that dolphins have names.... uh, and that they, um, and that they, when they whistle to each other, they have a, a particular, uh, whistling sound they make which identifies themselves like a call sign. Like you might say, you know, "Delta 214, this is Tower, come in."

   12. CWChris Williamson12:26

       (laughs)

   13. NCNicholas Christakis12:27

       And, and, and that means, you know, that's identify- and that's how the dolphins repeatedly say, "I am speaking now. This is me."

   14. CWChris Williamson12:34

       Yeah.

   15. NCNicholas Christakis12:34

       And the other dolphins go, "Oh," you know, that's, you know, that's Chris speaking, not Nicholas. They can tell the difference.

   16. CWChris Williamson12:40

       Yeah.

   17. NCNicholas Christakis12:41

       So, so, um, and now some birds can do it too, incidentally. There's some evidence that, uh, certain, uh, very social birds-

   18. CWChris Williamson12:48

       Can ravens do it? Ravens are badasses.

   19. NCNicholas Christakis12:51

       Yeah, ravens are very bad. I don't know about ravens and individuality. I'm sure it's known, I just don't know the answer.

   20. CWChris Williamson12:56

       Ravens are crazy clever, man. Uh, uh-

   21. NCNicholas Christakis12:57

       Yes. Very, very -

   22. CWChris Williamson12:58

       ... love finding out about ravens and, uh, uh, cephalopods. They're my two little-

   23. NCNicholas Christakis13:03

       Yes.

   24. CWChris Williamson13:04

       ... obsessions at the moment.

   25. NCNicholas Christakis13:05

       Yes. Yes. I think if you come back in, uh, in, um, 20 million years, I think ravens may be the ascendant species on the planet. In 100 million, it may be octopuses.

   26. CWChris Williamson13:17

       Fantastic.

   27. NCNicholas Christakis13:17

       Uh, so it feels like-

   28. CWChris Williamson13:18

       I can't wait for the war between the ravens and the octopuses.

5. 13:21 – 14:21

   Octopuses

   1. CWChris Williamson13:21

   2. NCNicholas Christakis13:21

      No, they'll die out. We'll die out, then the ravens will be ascendant. Then the ravens will die out, the octopuses will be under water.

   3. CWChris Williamson13:26

      Sweet. Go for it.

   4. NCNicholas Christakis13:26

      And then they will evolve. There's actually a lot of debate about whether in other planets submarine animals could evolve into sophisticated civilizations because of the impossibility of having fire-

   5. CWChris Williamson13:41

      Fire.

   6. NCNicholas Christakis13:41

      ... under water.

   7. CWChris Williamson13:42

      Yes.

   8. NCNicholas Christakis13:42

      So some people speculate, ma- most people think this would not be possible just to be a terrestrial mammal, a terrestrial animal to have a civilization. But other people think that's just us being anthropomorphic, that in some alien planet there could be, um, uh, very smart underwater creatures that, for example, develop the capacity to create air bubbles into which they put fire.

   9. CWChris Williamson14:06

      Oh, wow.

   10. NCNicholas Christakis14:07

       Or they have other, other technologies we can't imagine, that they manipulate the natural world in some way. So who knows? But anyway, uh, it'll be octopuses 100 million years. That's my prediction. You can come back and let me know if, if I just didn't (laughs) work out as I predicted.

6. 14:21 – 14:49

   Children of Time

   1. NCNicholas Christakis14:21

   2. CWChris Williamson14:21

      I got you. Um, have you ever read Children of Time by Adrian Tchaikovsky?

   3. NCNicholas Christakis14:27

      No, but I do talk about science fiction utopias and dystopias in my book, because, uh, one of the things that I try to do is I try to imagine sort of counterfactual s- types of social order.

   4. CWChris Williamson14:39

      Mm-hmm.

   5. NCNicholas Christakis14:39

      So I look at science fiction authors to see, you know, what kind of s- what kind of crazy social worlds did they come up with, and to what extent did those resemble or not resemble our own.

7. 14:49 – 17:15

   Young Planets

   1. NCNicholas Christakis14:49

   2. CWChris Williamson14:49

      Yeah. I think if you've got-

   3. NCNicholas Christakis14:50

      What's the last thing you were gonna say?

   4. CWChris Williamson14:51

      If you've got room in the reading schedule over the coming months, I highly recommend Children of Time by Adrian Tchaikovsky, was a, I think Pulitzer Prize award or some, some crazy big prize award. Um, and in that, future civilization of Earth creates a rapidly evolving amendment to the genome, and then throws a bunch of monkeys, primates, onto a planet which is habitable, and they've all got this particular amendment. And the thinking is, "We will go to sleep for a long time, and over a shorter period of time, like a couple of million years, they will go from being normal primates to these highly ascendant beings." What happens is, all of the m- this isn't, this doesn't spoil the story, thankfully. All of the monkeys burn up on entry, and it turns out that the only couple of species that are left to absorb this particular kind of genetic information are spiders and ants.

   5. NCNicholas Christakis15:49

      (laughs)

   6. CWChris Williamson15:49

      And you see what happens over a few million years, and Adrian rolls the clock forward about how they all evolve. And one of the things, really interesting, that he touched on was when you have young planets, you don't have the mineralogy. Mineralogy? You don't have the minerals.

   7. NCNicholas Christakis16:07

      Yeah. Uh, yeah, no, not mineralogy. It's, um, uh, I mean, uh, I th- I can't remember the word right now. Go on.

   8. CWChris Williamson16:12

      (laughs)

   9. NCNicholas Christakis16:12

      Yes, you don't have the right minerals. Yes.

   10. CWChris Williamson16:14

       (laughs)

   11. NCNicholas Christakis16:14

       Yes.

   12. CWChris Williamson16:14

       Um, you don't have the right mineral makeup to be able to create, uh, like smithing and stuff like that, 'cause it's just not n- not existed for long enough to have those fossil fuels, et cetera, et cetera.

   13. NCNicholas Christakis16:24

       Yeah.

   14. CWChris Williamson16:24

       Um, so they create biological technology. It's absolutely fascinating. They make, um, they make a computer, essentially a computer, out of, um, pheromone-controlled ants linked together in a hive. Oh, it's-

   15. NCNicholas Christakis16:39

       Yes. Yes.

   16. CWChris Williamson16:39

       ... it's really, really cool. But I mean, getting out of the realm of science fiction and back to the, back to the real world, um, I totally get what you mean. The, the fact that we are a social species, the fact that we can tell each other apart, it shows that there has to be a degree of collaboration. And also, a lot of what we've been learning about recently, listeners will remember, uh, William Von Hippel's episode, which was fascinating, talking about pair bonding, talking about the fact that you have to spend a lot of time with the partner to protect the child. Um, all of this, I guess, lends credence to the fact that we're an incredibly social species.

8. 17:15 – 20:31

   Pairbonding

   1. CWChris Williamson17:15

   2. NCNicholas Christakis17:15

      Yeah, I talk about pair bonding, and o- one of the things that's b- many people take for granted is that, you know, we could be a species that just had sex with each other, but we don't just have sex with each other, we are attached to each other. We tend to be attached to our partners. This is very rare, uh, in the ma- ma- ma- mammals. It's common in birds, actually, which is another interesting thing again. But, um, in mammals, uh, you can have a one-off kind of reproductive interaction, and you don't stay together f- in a kind of monogamous way for a sustained period of time and multiple, uh, you know, offspring being produced by the same union. But we do do that, and in humans that sense of attachment is expressed or felt as love, that we love our partners. And there's interesting ideas as to why we do that. You already alluded to one of them. One has to do that if you have love between partners, you can have more successful, uh, higher number of surviving offspring. So the, uh, so the male will stick around to help invest in the young...... but, um, but he will only do that if he can be c-... This is the theory. If, uh, if he can be confident that those are his offspring, not another man's offspring. And one of the ways that women will signal that to the male, that females will signal the fema- male, is by, uh, by love, by expressing love for them in a way. So, and, uh, anyway, so there, there's, there's some interesting ideas about the evolution of pair bonding. Why, why we have this, this, this phenomenon that is all around us, that if you stop and think about it, is unnecessary. We could be a sexually reproducing species without having an emotional attachment, and yet we do feel this attachment. And the reason is Y, it's part of our nature, um, what purposes it serve. And one of the purposes is what you alluded to it, it's felt to enhance, uh, reproductive, uh, fitness.

   3. CWChris Williamson19:03

      Yeah. Um, so why are we assos-

   4. NCNicholas Christakis19:05

      And I should say, in the book I talk about this sense of attachment is seen of course in homosexual unions, it's seen in polyandry, which of course not reproductive unions, it's seen in polyandry, it's seen in polygyny, it's seen in monogamous, uh, cultures. So the important thing that's very constant the world over is not how we pa- it's, it's seen in arranged marriages. So, so even though love is seen as a dangerous phenomenon in countries that have arranged marriages, it's dangerous before marriage.

   5. CWChris Williamson19:33

      (laughs)

   6. NCNicholas Christakis19:34

      Even in countries with arranged marriages, love is seen as a very much to, desired outcome of marriage.

   7. CWChris Williamson19:39

      Yeah.

   8. NCNicholas Christakis19:39

      So, so it's seen as a desirable and normal property to love your mate. And if you measure, uh, using some various psychometric scales, sort of, uh, com- the, sort of the passionate love scale is one of them, uh, of partners, you, looking at arranged and, and, uh, marriages and, and non-arranged, or so-called love matches, within a few years of marriage, there's no difference. In fact, there's evidence that the divorce rate, more than a little evidence, that the divorce rate, of course it's complicated to know why, but the divorce rate is also lower in arranged marriages. So anyway, no matter what the marital system, and there are many all over the world, one of the universals is that people love their partners, which is beautiful actually, if you think about it. I mean, one of my arguments is that these qualities that are universal also are good. Um, and, and in fact, that's one of the reasons they're universal, is that they, they were fitness enhancing. They made our world better for us.

9. 20:31 – 24:36

   Polyamory

   1. NCNicholas Christakis20:31

   2. CWChris Williamson20:32

      I recently did a podcast with, uh, Caleb Jones, who is a very big non-monogamy advocate.

   3. NCNicholas Christakis20:39

      Yes.

   4. CWChris Williamson20:39

      And that, I found that incredibly interesting to hear his point of view, and the listeners will at home. I don't want to delve too deeply into that, but I'm thinking an awful lot about what it is that he was talking about, and he also alluded to the, uh, the divorce rate, the increasingly, uh, rapidly increasing

   5. NCNicholas Christakis20:54

      Well, there are some, there are some people, I mean, just as a, as a cer- sort of a, a, a moral matter, I have no issues with polyamory, and, um, uh, and I, I don't think, um... And there's certainly some people who find that very appealing, and I think that's totally fine. I mean, they can find each other, and they're adults, and they can do, in a free society what they want. But there's no, to my knowledge, no successful society or even commune that has endured long, and I discuss this in the book, that's been organirized- organized around polyamory. Um, it's, it's a very unstable, uh, arrangement for a, a large group of people. It's not necessarily unstable for couples. I know many cup- not many, I know a couple of couples that practice polyamory among themselves.

   6. CWChris Williamson21:37

      Mm-hmm.

   7. NCNicholas Christakis21:38

      But I don't, I don't know of any society that's organized that way, or even any commune that has survived more than one or two generations organized around polyamory.

   8. CWChris Williamson21:48

      Interesting.

   9. NCNicholas Christakis21:49

      Many have tried.

   10. CWChris Williamson21:50

       Yeah. (laughs)

   11. NCNicholas Christakis21:50

       You know the reason... Do you know the, do you know the reason? It's very interesting actually. So, um, so if you think about the establishment of Utopian sects or communes, they have a problem, which is that they want the group members to have allegiance to the whole community, to the... You're supposed to feel a member of the whole community.

   12. CWChris Williamson22:11

       Mm-hmm.

   13. NCNicholas Christakis22:12

       And, and this is why, for example, in many communes, not all, and also in certain totalitarian states, the, the family unit is a threat to the loyalty that the individuals, the allegiance they feel to the state-

   14. CWChris Williamson22:25

       Mm-hmm. Mm-hmm.

   15. NCNicholas Christakis22:25

       ... or to the commune. So they try to break down the family. Kibbutzes in Israel tried to do this also, by the way, sort of break down the family unit. Also, they try to break down friendships. For example, in East Germany, everyone was... You, you couldn't have friends. You were, because you, there could be, you know, Stasi agents. Everyone was ratting on everyone else. So this type of so- this type of breaking down intimate connections or friendly connections between people is, is often seen as an, as, as necessary in order to foster allegiance to the total group, the totality. But here's-

   16. CWChris Williamson22:55

       Very Orwellian.

   17. NCNicholas Christakis22:57

       Yes, yes. But here's... It is. But here's the thing about, uh, sexuality and, uh, love of partners. So some communes address the problem that humans naturally love their partners and wish to be in love and wish to be loved. This is a very natural thing that most people feel and all societies manifest. Um, this could be seen as a threat to the, to the maintenance of kind of social cohesion for these Utopian sects, or, or, or, uh, or, for example, we're talking about now, but they have adopted very different practices to address that. Some sects have tried to adopt polyamory. So they say everyone can... There's no, we don't want any sexual jealousy. Everyone can have sex with everyone else.

   18. CWChris Williamson23:41

       Brave New World.

   19. NCNicholas Christakis23:43

       Yes.

   20. CWChris Williamson23:43

       (laughs)

   21. NCNicholas Christakis23:44

       So, uh, so, but again, for the reasons we just discussed, ****** gone to the produ- opposite extreme, nobody can have sex with anyone else, a totally celibate. But both of those extremes are serving the same purpose. If you think about it, both those sects that want you to have sex with everybody and those sects that want you to have sex with nobody, in both of those cases, they're trying to break down a kind of intimate connection to particular people. They're trying to anonymize or, or atomize the experience.... so, so the paradox is that in communes, you could, these very opposite practices actually are in the service of the same end-

   22. CWChris Williamson24:21

       Mm.

   23. NCNicholas Christakis24:21

       ... which is to foster allegiance to the group. The Shakers, for example, famously prohibited sex, which of course makes it very difficult to-

   24. CWChris Williamson24:28

       (laughs)

   25. NCNicholas Christakis24:30

       ... sustain the community-

   26. CWChris Williamson24:31

       (laughs)

   27. NCNicholas Christakis24:31

       ... if you can't reproduce. But, uh, but anyway, I'm sorry, this is a digression within a digression.

   28. CWChris Williamson24:35

       No, I get it.

10. 24:36 – 27:24

    Friendship

    1. CWChris Williamson24:36

    2. NCNicholas Christakis24:36

       So-

    3. CWChris Williamson24:36

       I get it. It's, it's gr- I mean, you've touched on a point that I wanted to go to there, which is the fact that humans naturally seek some sort of companionship, and by removing the ability to, to go deep with either some people or anyone, like either-

    4. NCNicholas Christakis24:55

       Yes.

    5. CWChris Williamson24:55

       ... everyone, everyone or anyone, you force people to look for this connection elsewhere, and that's where the state comes in. So is the reason that humans are a sort of-

    6. NCNicholas Christakis25:05

       Yeah, but the state, the state can't take the place. You see, one of the things that's also true is that in our ancestral environment, being alone was deadly. So we, uh, for reasons I discuss in the book, we ex- I explore the origins of friendship and some theories as to why we developed the capacity to form, why we live in groups, all of this stuff which has to do with coping with the dangers in the environment. Uh, so, uh, so, so feeling, we, we evolved this kind of sense that, uh, being alone, uh, could be dangerous and risky, and we crave intimate friendships that we can all, every human being that w- w- is listening to this, m- almost everyone, knows what I'm talking about when I say you have an intimate friendship, someone you trust, and you, you talk to them, and, uh, and you have a sense that they know you as a person, and they value you as special and unique. You're irreplaceable to them. Each of us is totally replaceable to strangers, but we are irreplaceable to our friends, right? We are unique individuals, and that friendship is special. So, so this, this, all this apparatus that we have, all these emotions and sensibilities and behaviors that sustain friendship, in the modern environment, where you're interacting with, uh, people anonymously, or where you go to bureaucracies and you interact with bureaucrats, so now instead of interacting with people face-to-face as individual people, you interact with them as replaceable cogs in a system. They're just, you know, it's the person at the Department of Motor Vehicles who's... you're interacting with, and they're doing their job. And, uh, we all sense that as awful, and, uh, and the reason we sense it as awful is because on some level, we recognize these are not... our evolved psychology is starting, "Warning, warning, warning, these aren't your real friends."

    7. CWChris Williamson26:53

       (laughs)

    8. NCNicholas Christakis26:53

       You know, these are, these are, these are not real relationships. And so we sense that kind of anomie. And this is why, incidentally, I also think that a lot of online interactions make people so miserable, because our evolved psychology wants real, intimate, face-to-face, deep, sustained social relationships, and instead what we get is, you know, acquaintances. And, uh, and, and that's immiserating, I think. So anyway, so it's kinda, all of this stuff is, is connected,

11. 27:24 – 28:34

    Online Connections

    1. NCNicholas Christakis27:24

       actually.

    2. CWChris Williamson27:24

       Absolutely. Uh, it's interesting that you touch on, um, the online connections, because, you know, it's a trope to say, "We're more connected than ever whilst feeling more alone," et cetera, et cetera-

    3. NCNicholas Christakis27:35

       Yes.

    4. CWChris Williamson27:35

       ... all that sort of stuff. Um-

    5. NCNicholas Christakis27:36

       That's correct.

    6. CWChris Williamson27:37

       Do you think it is, there's something specific about the face-to-face interaction, about the fact that, um, the, uh, I think it's more than half of communication cues are non-verbal, and a WhatsApp chat doesn't quite fulfill that need?

    7. NCNicholas Christakis27:52

       Yes. I mean, for example, uh, in promoting the book or supporting the book, I've done a whole bunch of interviews, and I've noticed that quite a few of the, like you, quite a few of the more sophisticated podcasters, even if there's gonna be an audio-only file-

    8. CWChris Williamson28:04

       Mm-hmm.

    9. NCNicholas Christakis28:05

       ... they want to do video. That's, in fact, I asked you at the beginning, I said-

    10. CWChris Williamson28:08

        Yeah.

    11. NCNicholas Christakis28:08

        ... "Are you gonna, we're gonna, we're gonna do this video, are you gonna record the video, or are you just-"

    12. CWChris Williamson28:12

        Yes.

    13. NCNicholas Christakis28:12

        "... we're just seeing each other?" Well, why is that? It's because the conversation is more natural, more fluid. I can see are you laughing at my joke or not.

    14. CWChris Williamson28:18

        Mm-hmm. Mm-hmm.

    15. NCNicholas Christakis28:19

        You know, I can see you're getting bored by what I'm saying, and I should move on.

    16. CWChris Williamson28:22

        Never. Never. (laughs)

    17. NCNicholas Christakis28:23

        You know, all of those things. (laughs) Yeah. All of those things, you know? So, um, you know, those are fundamental parts of how we communicate.

    18. CWChris Williamson28:33

        Got

12. 28:34 – 31:41

    Human Evolution

    1. CWChris Williamson28:34

       you. So going back to the real beginning, the evolutionary, um, uh, uh, I guess, prerogative for why we are a social species, is it simply that a human on its own is a human that's dead, and our main, uh, advantage as evolving humans was that we could coordinate well as a group? Does that appear to be it?

    2. NCNicholas Christakis28:56

       There are many, there are many, there are many things that have made us one of the most ascendant species on the Earth. Humans, I think, have the broadest, or one of the broad, the... Humans have the broadest, I think ants also have an equally broad, but let's side, set that aside for a moment.

    3. CWChris Williamson29:11

       Yep.

    4. NCNicholas Christakis29:11

       One of the broadest geographic ranges of any animal species. So everyone knows that some animals live in some places, but not in other places.

    5. CWChris Williamson29:18

       Yeah.

    6. NCNicholas Christakis29:19

       But there's no place humans don't live.

    7. CWChris Williamson29:21

       Mm-hmm.

    8. NCNicholas Christakis29:21

       We live all over the world.

    9. CWChris Williamson29:22

       Mm-hmm. Mm-hmm.

    10. NCNicholas Christakis29:22

        From the Arctic to the Equator, in deserts, in, in snow-covered plains. We live everywhere. And the reason we do that is not because of our, our bodies. We haven't adapted physically, although we have also, in some cases, done, adapted physically.

    11. CWChris Williamson29:36

        Yep.

    12. NCNicholas Christakis29:36

        It's because of our culture. It's because of what we can teach each other. It's because of our ability to accumulate knowledge. So slowly over generations, people invent kayaks, or they invent parkas. Or slowly over generations, people invent technologies to f- uh, to find water in the desert. And, uh, and because of those innovations, we are able to, uh, to transmit that knowledge from person to person. And so in order to survive, we have to be part of a community that has this type of knowledge. A teenager, we, we do a lot of work with the Hadza, well, actually, we don't anymore, but we used to, which is, uh, one of the last, uh, forager groups on the planet. They live around Lake Eyasi in Tanzania.... there are only about a thousand of them left. These people hunt and gather for their food, just like every human did until about 10,000 years ago.

    13. CWChris Williamson30:21

        Just to interject there, what, um, period of history do they align with?

    14. NCNicholas Christakis30:26

        The Hadza are still alive.

    15. CWChris Williamson30:28

        No, no, what, what, what-

    16. NCNicholas Christakis30:29

        But the Ha-

    17. CWChris Williamson30:29

        ... would they be representative of in our past?

    18. NCNicholas Christakis30:31

        Oh. Uh, the way we lived until about before the Agricultural Revolution, till about 10,000 years ago.

    19. CWChris Williamson30:37

        Wow.

    20. NCNicholas Christakis30:37

        So the Hadza, the Hadza hunt and gather for their food, they have no material possessions to speak of, they sleep out under the stars. Uh, and, um, and they live in this envi- environment in, in, in Tanzania, around Lake Eyasi, and, um, and if, if I dropped you there, or me there, we would, we would be killed in an environment, we would die in an environment that a Hadza, you know, seven-year-old could survive.

    21. CWChris Williamson31:04

        Flourishes in, yeah.

    22. NCNicholas Christakis31:05

        Yes. Yes. And it's not because of the differences in our bodies, it's because we have none of the knowledge. And so the knowledge is of course transmitted socially. It lives, the knowledge lives in the interstices between people. That's where the knowledge lives and survives across time. Then it comes into my brain, and then it goes into your brain, and so forth. So it spreads across these connections, this knowledge, and is produced by groups of people, this, this knowledge. And so this is what makes it possible for us to survive, uh, this, this, this living socially.

13. 31:41 – 34:30

    Compounding Interest

    1. NCNicholas Christakis31:42

    2. CWChris Williamson31:42

       I think one of my favorite quotes from Warren Buffett is that compounding interest is the, uh-

    3. NCNicholas Christakis31:46

       Yes.

    4. CWChris Williamson31:47

       ... eighth w- eighth wonder of the world, and it's occurring as we see in front of us with knowledge, right? I can put my hand in a-

    5. NCNicholas Christakis31:53

       Yes.

    6. CWChris Williamson31:53

       I can put my hand in a fire, burn my hand, and then tell you, and you know not to put your hand in a fire without having to go through it. That fact alone-

    7. NCNicholas Christakis32:02

       Correct.

    8. CWChris Williamson32:02

       ... cumulating over however many generations-

    9. NCNicholas Christakis32:06

       Yes.

    10. CWChris Williamson32:06

        ... leads to me and you talking over Skype.

    11. NCNicholas Christakis32:09

        Correct.

    12. CWChris Williamson32:10

        (laughs)

    13. NCNicholas Christakis32:10

        And in fact, in fact, you could take, you could take, you could take the average British, uh, you know, uh, uh, high school student that, uh, studied calculus, let say, in, uh, when they were 17, and if you move them back 500 years, they'd be the smartest mathematician on the planet.

    14. CWChris Williamson32:26

        Mm-hmm.

    15. NCNicholas Christakis32:27

        I mean, this, you know, this, th- th- the, and w- and, and we get calculus, which, you know, Isaac Newton and, and Leibniz invented, actually just as an aside, we learn calculus, we are taught calculus at the speed at which Newton invented it.

    16. CWChris Williamson32:42

        (laughs)

    17. NCNicholas Christakis32:43

        It's- it's astonishing. Isaac Newton (laughs) takes a year to invent calculus. I mean, it's just, the man is just unbelievable.

    18. CWChris Williamson32:52

        Forces of nature.

    19. NCNicholas Christakis32:53

        Ah. Anyway, so and now, but the point is, you're born today, and you inherit all this stuff that everyone before you, all the domesticated animals. Other people domesticated these animals thousands of years ago.

    20. CWChris Williamson33:06

        (laughs) Yeah.

    21. NCNicholas Christakis33:07

        A- a- all the domesticated plants. All the roads which were built in England starting with the Romans.

    22. CWChris Williamson33:11

        Yeah.

    23. NCNicholas Christakis33:12

        Calculus, which was invented by Newton 500 years ago. It's yours for free.

    24. CWChris Williamson33:17

        (laughs)

    25. NCNicholas Christakis33:17

        All of this stuff. How to smelt iron, you know, all the knowledge about iron and fishing. How to fish hooks. I talk about fish hooks in the book, like the invention of fish hooks. The wheel. You g- fire. You go on and on and on. All of this stuff, which was just given to you when you were born, was cumulated by other humans across time. And, um, and it's this that makes us so powerful a species, 'cause we have, if you think about it, rather pathetic bodies. I mean, there are very few animals our size. I don't think there's any animal our size that we could take in a one-on-one battle. Uh, I mean, we-

    26. CWChris Williamson33:52

        You probably about-

    27. NCNicholas Christakis33:53

        ... I mean, even a- a- a doe.

    28. CWChris Williamson33:55

        Yeah, yeah, yeah.

    29. NCNicholas Christakis33:55

        A doe would kill us.

    30. CWChris Williamson33:57

        Yeah.
14. 34:30 – 36:02

    Duck or Horse

    1. NCNicholas Christakis34:30

       that are-

    2. CWChris Williamson34:30

       Yep.

    3. NCNicholas Christakis34:30

       ... making us powerful.

    4. CWChris Williamson34:31

       I've got, I've got one of the most important questions to ask you right now, uh, Professor-

    5. NCNicholas Christakis34:35

       Okay.

    6. CWChris Williamson34:35

       ... Christakis, and it's, would you rather fight one horse-sized duck or 20 duck-sized horses?

    7. NCNicholas Christakis34:46

       20 duck-sized horses.

    8. CWChris Williamson34:47

       What's your, what's your strategy gonna be?

    9. NCNicholas Christakis34:50

       You kick and, kick one and move, kick and move, kick and move.

    10. CWChris Williamson34:53

        Yeah.

    11. NCNicholas Christakis34:53

        Really...

    12. CWChris Williamson34:53

        Got you.

    13. NCNicholas Christakis34:54

        Yeah, and, and, I mean, you, actually you move to the place where you fell the first opponent.

    14. CWChris Williamson35:00

        Got you. And you pile these bodies up like 300.

    15. NCNicholas Christakis35:04

        Well, you said 20 horse-sized-

    16. CWChris Williamson35:05

        Like in, like in 300, the movie.

    17. NCNicholas Christakis35:08

        Ah, right.

    18. CWChris Williamson35:09

        Yeah.

    19. NCNicholas Christakis35:09

        Yes.

    20. CWChris Williamson35:09

        And you just got mounds of, mounds of these dead duck-sized horses everywhere. Well, cool. I think, so I asked one of the fittest men on the planet, Dan Bailey, this question as well, and he gave the exact same answer. So you are, you're on a level with elite athletes-

    21. NCNicholas Christakis35:23

        (laughs)

    22. CWChris Williamson35:23

        ... with regards to your answer. (laughs)

    23. NCNicholas Christakis35:26

        Well, I, I spent years, I spent years training in the martial arts, but that's another story.

    24. CWChris Williamson35:31

        Practicing duck-sized horse kicking.

    25. NCNicholas Christakis35:34

        No. Practicing...

    26. CWChris Williamson35:35

        (laughs)

    27. NCNicholas Christakis35:36

        To get your black belt, they put you in a ring with four guys, and, uh, and, um, y- you have to learn how to fight against multiple opponents, and, uh, you know, it's not easy, it's, for various reasons. Anyway, there are basic techniques you can use, so.

    28. CWChris Williamson35:49

        If I, if I, if this sit- situation occurs, I'm gonna call on you. So, um-

    29. NCNicholas Christakis35:53

        No, no.

    30. CWChris Williamson35:53

        (laughs)
15. 36:02 – 38:59

    Advantages and Disadvantages of Modern Society

    1. CWChris Williamson36:02

       talked about-

    2. NCNicholas Christakis36:02

       Yes.

    3. CWChris Williamson36:02

       ... we've, we've talked about kind of our evolutionary past. Moving into where we are now, did you reflect in the book on what, uh, what the advantages and disadvantages of modern society are doing to our desire for social cohesion?

    4. NCNicholas Christakis36:20

       Um, yes and no. I mean, I'm interested in, I'm interested in the long arc of our prehistorical past, you know? So we've evolved over hundreds of thousands of years, and it's only in the last 10,000 years that we've even had history at all. That we've had historical or political or cultural, uh, well, not c- cultural, we've had a long time, but specific kinds of cultural forces acting on us. Um, so I'm interested in the ways in which our capacity for social interaction and, and, and living togeth- living together were shaped at a time that preceded the invention of cities or the invention of the internet or anything like that. Now, these cultural products, the cities and internet and everything else, are also shaping our evolutionary trajectory, but that's not the main driver of the way we live socially, uh, today. For example, my, uh, Greek grandmother was born in a, in a, in a little village in, uh, in Southern Greece, and, um, if she's not alive anymore, she was born over 100 years ago, but if you, you could, if you had asked her when she was alive what, um, you know, when she was a 10-year-old girl, how many friends did she have? And she would have said, "I have one or two best friends, and there are four or five of us girls, we hang out together." In this little village in Southern Greece, you know, 100 years ago. And if you could ask my daughter, Lena, uh, who's now 21, but back, let's say when she was 10, you know, 10 years ago, you ask her the same question and she has an iPhone in her pocket, she would give you the same answer.

    5. CWChris Williamson37:53

       Yep.

    6. NCNicholas Christakis37:54

       So it's something deep and fundamental about our nature, about this desire for one or two best friends, most people, not everyone, about, about, uh, 90%, 92% of people in developed countries have, uh, one, at least one best friend, or one intimate, very intimate social contact. 8% of people-

    7. CWChris Williamson38:13

       That's interesting.

    8. NCNicholas Christakis38:14

       8% have no one, which is very sad. Some of these people are elderly widowers, their spouse has died, everyone they know has died.

    9. CWChris Williamson38:20

       Yeah.

    10. NCNicholas Christakis38:20

        Others of them, others of them have other sort of, um, uh, disabilities that make it difficult for them. But anyway, so most people have this sense of they have one or two best friends, and there are four or five of, uh, you know, your intimate friends that you hang out with.

    11. CWChris Williamson38:34

        Okay.

    12. NCNicholas Christakis38:34

        And then there are broader circles. The point is, that technology didn't change that, right? I mean, Chris, this is a cultural constant. In fact, we've done this. We've looked around the world. In my laboratory, we've mapped networks in, in, uh, in Uganda and in, and in Tanzania and in, and in India and in Honduras and in the United States, and wherever you go, you find the same thing. People organize themselves in the same way. So it's not to do with the technology.

16. 38:59 – 43:02

    Maximizing Fitness

    1. NCNicholas Christakis38:59

    2. CWChris Williamson38:59

       Does that specifically maximize fitness, do you think, or did it over the years? Like, the likelihood of surviving?

    3. NCNicholas Christakis39:05

       Yes. Yes. I think that the specific mathematical structure of the social networks that we make, and we've done some other evidence on this using a variety of tools from genomics and also some actual f- anthropological tools, uh, that the, the mathematical structure of networks that we make, I believe, have been shaped by natural selection.

    4. CWChris Williamson39:27

       How so?

    5. NCNicholas Christakis39:28

       And, um, we... Okay, well, this is a little hard to explain, so it's a bit of a tangent, but-

    6. CWChris Williamson39:33

       Let's do it.

    7. NCNicholas Christakis39:33

       ... do you want me to...

    8. CWChris Williamson39:34

       We've got it, we've got it.

    9. NCNicholas Christakis39:35

       Okay.

    10. CWChris Williamson39:35

        The listeners, the listeners are rubbing their hands together. They're ready to go. Come on.

    11. NCNicholas Christakis39:38

        Okay, so here we go. So, um, there's a very fundamental property about human social networks, which is that we have this thing called degree assortativity. Degree is the number of connections that each person has. So it's, it's how many friends you have. You have, you have a degree five, you've got five friends. I have degree 10, I've got 10 friends. Someone else has degree two, they've got two friends. And degree assortativity means people with similar numbers of friends are preferentially connected. So popular people befriend popular people and unpopular people befriend unpopular people, okay?

    12. CWChris Williamson40:10

        Mm-hmm.

    13. NCNicholas Christakis40:11

        This property of degree assortativity is the opposite of a property known as degree disassortativity, which is the way the airport network is organized. So unlike human social networks which have degree assortativity, popular people are connected to popular people and unpopular people are connected to unpopular people, in the airport network, it's the opposite, right? We have a hub and spoke system. So the unpopular airports with few connections aren't connected to other small airports with few connections, they're all connected to London and Gatwick and Chicago and Denver.

    14. CWChris Williamson40:41

        Yes.

    15. NCNicholas Christakis40:41

        And if you want to get from one place to another place in an airport network, you've got to go from, uh, you know, New Haven, Connecticut to Chicago, and then from Chicago, you can go anywhere.

    16. CWChris Williamson40:53

        Yeah.

    17. NCNicholas Christakis40:53

        Right? You can fly to any city. So in two hops you get there because the network is organized in this degree disassortative way, okay?

    18. CWChris Williamson41:01

        Yes.

    19. NCNicholas Christakis41:01

        Now, if you think about it, in which of those two kinds of networks, if an, if an epidemic, if you infected a random person in, in these two networks, a degree assortative and a degree disassortative network, in which of those two kinds of networks would you get a bigger epidemic?

    20. CWChris Williamson41:20

        Uh, yes. Of course.

    21. NCNicholas Christakis41:22

        You should have the, you should have the intuition that you'll get a bigger epidemic in the degree disassortative network because in the degree disassortative network, the first person that gets infected, the next step, they are, uh, they are connected to the most popular person, and then that person spreads it to everybody. So, so in a degree disassortative network, epidemics will spread very rapidly. Whereas in a degree assortative network, like humans make, epidemics can be contained within one part of the network. So one unpopular person gets an infection and they infect their unpopular friends and they are all infected over there.

    22. CWChris Williamson42:01

        Yeah.

    23. NCNicholas Christakis42:01

        The rest of us are okay-

    24. CWChris Williamson42:02

        Yeah.

    25. NCNicholas Christakis42:02

        ... because they're not connected to the popular person, let's say. The story is more complicated than this, but this is the gist. So what's very interesting to me is that of all the kinds of ways that we could f- form social networks, we form them to have this property of resistance to epidemics.... because we form a degree assortative networks. And amazingly, elephants do the same thing, this is discussed in the book-

    26. CWChris Williamson42:29

        Yep.

    27. NCNicholas Christakis42:29

        ... and so do whales, so do orcas. And so other social mammals, when they go about making their friendship networks, even though w- our last common ancestor with those, with elephants was 85 million years ago, they independently have converged on the same way of social, socially organizing themselves that gives them this sort of epidemic resistance property at the population level.

    28. CWChris Williamson42:55

        That's so fascinating.

    29. NCNicholas Christakis42:57

        So these are ... So yeah, so these are some ideas about, you know, uh, uh, in response to what you asked.

17. 43:02 – 45:52

    Dunbars Number

    1. NCNicholas Christakis43:03

    2. CWChris Williamson43:03

       That's really fascinating, and it makes complete sense. Um ...

    3. NCNicholas Christakis43:06

       Yeah.

    4. CWChris Williamson43:06

       I, I, I totally understand. I think, um, one of the things that's come to mind, Dunbar's number, which is the-

    5. NCNicholas Christakis43:15

       Yeah.

    6. CWChris Williamson43:15

       ... supposed upper limit, upper bound that a human can have in terms of friends. Did you look at that? And I've never delved into this. Is there, is that like a gospel or is there some, uh, some criticism of that?

    7. NCNicholas Christakis43:29

       Yeah, so Robin Dunbar is a very famous, uh, physical anthropologist at Magdalen College at Oxford. He, um, he, uh, is well known for this finding, which is c- is a correct finding, uh, which is that, uh, human beings, it's not the upper limit. It's that on average our capacity to, uh, track social relationships is at about 150. And he made this prediction based on a comparative analysis of different primate species and the size of their groups. And there's been abundant evidence sort of confirming his ideas in this regard. And the notion is that, is that you are able to ... Our brains are endowed with the ability to ... And, and he uses as a kind of approximation of what he means by knowing someone is, knowing someone is w- if you can pick up your conversation where you left off, where you left it off before.

    8. CWChris Williamson44:19

       Uh-huh.

    9. NCNicholas Christakis44:19

       So you, uh, remember enough of who they are and what kinds of things you're discussing so that if you meet them again after an absence, you can pick up the conversation. And so he, the number of people we can do this with is about 150. We can, uh, we, we can know if these people are friends or enemies. We can also know something about the relationships of all the pairs of people. So you know, if you have 100 friends, you know does this person like that person or not get along? And, for example, many of the listeners will have this experience. Some listeners will have gone to high schools that had small, uh, I, I know the word is different in Eng- in British English and American English, so when I say class, I mean-

    10. CWChris Williamson44:55

        Yep.

    11. NCNicholas Christakis44:55

        ... the group of people that are in, you know-

    12. CWChris Williamson44:57

        Your year.

    13. NCNicholas Christakis44:58

        Your year.

    14. CWChris Williamson44:59

        Yeah.

    15. NCNicholas Christakis44:59

        Exactly. So there might be in, in, in your school, let's say it's a, it's a, it's a, it's a private school, and there are a small year of, let's say, 100 students.

    16. CWChris Williamson45:09

        Yep.

    17. NCNicholas Christakis45:10

        If you went to such a school, you know that you knew every other student, and you knew something about the relationships of every other student. And if you contrast that, for example, with a, um, with a municipal school that's run by the state, which is bigger, and there might be 1,000 people in your year or 500 people in your year, you know, you didn't know all those 1,000 people, uh, and you didn't know the relationships of all those people, and that's a limitation of your, of your brain, of our brains. So, um, so this is what Robin Dunbar's, uh, arguments are about.

    18. CWChris Williamson45:41

        Do you think that that was maximizing evolutionary fitness as well? I do remember when I spoke to-

    19. NCNicholas Christakis45:46

        No, I think in our ancestral environment, we didn't need two k- brains that could track larger numbers of people, because

18. 45:52 – 46:47

    Group Size

    1. NCNicholas Christakis45:52

       there weren't bigger groups.

    2. CWChris Williamson45:53

       Ah-huh. I see. Apparently, I was, again, uh, William Von Hippel is the closest, um, uh, podcast that I've done to what we're discussing at the moment. I think he alluded to the fact, or at least posited that groups over, he said, around about 50, he thought would tend to disband. He thought that groups, at least when we're talking, uh, Australopithecus, that kind of era-

    3. NCNicholas Christakis46:16

       Uh-huh.

    4. CWChris Williamson46:16

       ... that those groups would disband into groups of 50 because the larger groups end up being, I think it was ... I, I, I can't remember the reason why, but he, I think he thought that was the case.

    5. NCNicholas Christakis46:29

       Uh, yes, and, and he may be right. I don't know the answer to that question. There's a l- there's a lot of, um, suggestive evidence about the group sizes of ancestral hominids. Um, we can certainly study living primates and do comparisons, and that's what, what Robin Dunbar did for his, uh, analysis.

19. 46:47 – 52:11

    Future Predictions

    1. NCNicholas Christakis46:47

    2. CWChris Williamson46:47

       Mm-hmm. I got you. So moving forwards, as we, as we go on, obviously you have looked at the past. Do you have any predictions about the future? Do you have any sort of suggestions for the future, for ...

    3. NCNicholas Christakis46:58

       Well, I mean, one kind of speculative set of ideas that interest me right now is, um, what I call hybrid systems of humans and machines. So increasingly, you know, the, the relationship between human beings and technology is an ancient topic. You know, Homer talks about this in the Iliad, you know, what's the role of bronze spears in warfare? You know, we invent a new, a new, uh, technology and it has, uh, you know, certain, um, implications, for example. Uh, or, or, you know, Odysseus uses the Trojan horse to get into the city, you know, that's a technology. Um, and, and, uh, you know, you had the Luddites, you know, breaking the, the looms, you know, in England, and so there's lots of ... You know, our relation to technology is complicated and longstanding. But what's different now is that we are beginning to endow these machines with, uh, a kind of volition of their own. I mean, th- they're not obviously human, they don't really have their own desires, but they're able to act independently, and they're living amongst us. So we have digital assistants like Alexa, for example, or we have autonomous vehicles on the car, on the road, so you're driving down the road, and there are mostly human drivers, but there are also some autonomous vehicles that are driving down the road and doing their thing. Um, or online, you know, we ... you have your Twitter friends and, you know, I'm on Twitter and some of the people that follow me, I think, are bots, you know, and so there they are. They're in the system. They're humans and some bots that are interacting. I call this a hybrid system, uh, because it's hybrid between humans and machines. But what's interesting to me ...... is not the interactions between a human and a machine, it's the ways in which the presence of those machines, acting as if they were human, modifies how we interact with each other. Let me give you an example. So you, uh, bring an Alexa into your home and the people who designed the Alexa make it, want to make it very obedient. They're not interested in you having to do, you could just say, you know, uh, you know, "Play Little Richard." You know? Or, "Play Beethoven." And the machine does what you ask. Or you know, "Order milk." Um, it doesn't, you don't have to say, "Please, could you order some milk?" Or, "Would you please, you know, do this?" Or whatever. You, you don't have to be polite to the machine.

    4. CWChris Williamson49:07

       Yeah.

    5. NCNicholas Christakis49:08

       So, but think about how the addition of this machine into a home might train a child to be rude, and it's not a problem if the child is rude to the Alexa, but then the child goes to the schoolyard and is rude to his or her friends.

    6. CWChris Williamson49:21

       Mm-hmm.

    7. NCNicholas Christakis49:22

       And so now we have a rude group of children that has arisen because of the introduction of this machine into the social system. Or you think about driverless cars. In a world in which we have only human drivers, they're all human, and eventually we'll have a world in which there are only autonomous vehicles. None of us will drive cars anymore, you'll go to racetracks to drive cars. That's like 30 years from now if not sooner. So, uh, and those cars will be, will be Bluetooth enabled and they will communicate with each other and they'll move in a kind of laminar flow down the highway or they'll entrain with each other and they'll be fine. There'll be no collisions, it'll be all fine. But between now and then, we're gonna have a hybrid system of humans and machines, and the question is, how should we program those autonomous vehicles so that as they move among us, they improve rather than degrade our behavior? So for example, the car maker might want to design the car to move very smoothly so that the occupant of the autonomous vehicle has a nice pleasant ride. But now the human drivers behind this vehicle might be lulled into a false sense of security and become inattentive, and so when they veer off to go and go to the part of the highway that has just human vehicles, these inattentive drivers might cause more collisions.

    8. CWChris Williamson50:32

       Mm-hmm.

    9. NCNicholas Christakis50:33

       Now, the person who bought the vehicle, the autonomous vehicle, and the designer of the auton- autonomous vehicle doesn't care at all about those people who are, you know, killing themselves over there because of the new bad driving practices. But we should care. So, so one of the things I'm concerned about is the ways in which these new technologies in the future are going to reshape our social interactions, are going to modify how we live together and might potentially threaten some of these fundamentally good qualities about how we have evolved to live together that you and I have been talking about.

    10. CWChris Williamson51:07

        Moving on, where can the listeners find you online if they want to find out a little bit more?

    11. NCNicholas Christakis51:12

        Uh, well, my laboratory is, uh, www.humannaturelab.net and, um, of course we've been talking about my book Blueprint: The Evolutionary Origin of a Good Society, which is available everywhere. Uh, and on my lab we have videos and paper, scientific papers and all kinds of other information.

    12. CWChris Williamson51:30

        If people want to delve deep, it will be in the show notes below along with the links to Blueprint and your Twitter. Uh ...

    13. NCNicholas Christakis51:37

        Yes, I'm on Twitter, of course.

    14. CWChris Williamson51:38

        You are incredibly interesting on Twitter. I'm looking forward to reading through some of your stuff I've got saved for this evening. Uh, Professor Christakis, I really appreciate your time. Thank you so much for coming on.

    15. NCNicholas Christakis51:47

        Thank you for having very much, Chris. I'm very grateful.

Episode duration: 52:07