Episode 49: Nicholas Christakis on Humanity, Biology, and What Makes Us Good

0:00:00 Sean Carroll: Hello everyone and welcome to The Mindscape podcast, I'm your host, Sean Carroll. And as you know, if you've been listening to this podcast, I'd like to mention books that I have written or am in the process of writing. My most recent book that has actually appeared is of course called The Big Picture. And it was an attempt to put together the laws of the physical world with the human side of things. And this is an element of a genre, right? There's a kind of book where you try to synthesize some gigantic picture of things. And yeah, there are successes and less successful books in this genre. Our guest today is Nicholas Christakis, who is the author of one of the most recent attempts in this genre. It is called Blueprint. Now, Nicholas unlike me is not a physicist, he's a... Well, it's hard to say what he is.

0:00:45 SC: I almost say he's a social scientist, but one of the things he brings to the table as an author of an incredibly sprawling book like this, is that he seems to be a professor of everything. He was originally a medical doctor, and now I have to read this from the back of his book, he is at Yale University, the Sterling Professor of Social and Natural Science. And particularly, he's appointed in the Departments of Sociology, Medicine, Ecology, Evolutionary Biology, Statistics and Data Science, and Biomedical Engineering, as well as being the co-director of the Yale Institute for Network Science. So he's a sociologist, a medical doctor, he studies ecology, and networks, applied math, a whole bunch of things.

0:01:25 SC: So, in Blueprint he's trying to put this all together, he's trying to write a book about humanity and what makes us special. Not just culturally, but how that relates to our biology, our genetics, how we came to be different than other animals in different ways. And he identifies what he calls the social suite, the list of, that's suite, S-U-I-T-E. So, it's a suite of characteristics that make us human. And some of them are good, things like the capacity for love or cooperation. Some of them might not sound so good, like the existence of ingroup bias, we like people like ourselves, we don't like people not like ourselves, the preference for hierarchies and so forth. But the overall message that he comes away with is an optimistic one, that's what makes this book special in a sense. He's not simply saying how terrible human beings are, he's saying that there's good reason to be optimistic about what we can become.

0:02:22 SC: And it's not a 100%, it's not at all determined. He has examples in the book for example, of societies that were created after shipwrecks so little semi-controlled experiments with small numbers of people. Some of these experiments went terribly wrong, but some of them turned out really, really well. So, Nicholas wants to make the case that what makes us human, is part of what makes us good and we do have reason to be optimistic about the future, of course as long as we don't destroy the planet or anything like that. So let's see how that's gonna happen, and let's go.

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0:03:11 SC: Nicholas Christakis, welcome to The Mindscape podcast.

0:03:13 Nicholas Christakis: Thank you so much for having me Sean.

0:03:15 SC: So I do, I wanna dive right in to the meaty substance, you've written a 500-page book. Very, very good. I've never quite reached the 500-page mark, in any of my books. I've come 400 and some, a couple of times. But you also... I'm equally intrigued by the About the Author section at the end of your book, because you have an MD, a PhD, you've been a hospice doctor, and you're talked about as a Sociologist. Tell us how you think about yourself and how you got to be this.

0:03:45 NC: Oh goodness, well you've said a little bit about the biographical details. I think, to me, one of the most interesting observations about the sciences, or more generally about scholarly inquiry is that innovation and novelty often come at the intersection of disciplines. And there's... This idea is often realized in many ways. I talk to my graduate students, I say, "Yes, you have depth, but also some breadth early on." Go to nearby meetings and conferences and departments and see what they're doing. And you'll never know when you get a good idea, unexpectedly, you might be building a kind of a laser, a laser device, and go to a talk by a biologist about how natural selection has solved a similar problem millions of years ago in the design of an insect eye for instance, or the same principal comes up when you think about civilizations and there's this wonderful lecture about when ideas have sex.

0:04:46 NC: Like innovations come at the intersection of trade routes, where people mix, and ideas mix. And I think the same thing happens in discovery. It's not just a pedagogic tool, it's not just an argument about the emergence of novelty and ideas at the sort of... At the civilization level. I think it happens at the level of a work of a practicing scientist, where if you cultivate some breadth in yourself, you're able to discover new things. So in my own career, I've tried to do that, I've tried to be as broadly educated as I can be, and I have rather enjoyed it.

0:05:25 SC: And so, but, let me play the part of the devil's advocate here.

0:05:30 NC: Yes.

0:05:31 SC: You've just cast this interdisciplinary nature of your work as a sort of rational instrumental good thing to do. So is it mostly that, or is it mostly that you just like it? [laughter]

0:05:45 NC: It's both. I derive a lot of satisfaction... Thing is I first, like most people, I think, again I wanna emphasize that I think it's important to have expertise. I'm not advocating for being a dilettante. I think it's important to have skills, to have depth, but I also think it's important to keep your head up and look around. And people of different disciplines and different people do that at different phases of their career. And in my case, I may have the investments in my 20s in both the natural and the social sciences, the biological and the social sciences, and I, over the course of my career I've tried very hard to keep those parts alive, and to look for opportunities for discovery at the intersection of those fields. So that's why, for instance, a lot of the work I've been doing has been on the evolutionary biology of friendship, for example.

0:06:34 SC: Right.

0:06:35 NC: How and why did we evolved to have friends? That's a question at the overlap of those fields. So it's been sort of deliberate.

0:06:43 SC: Yeah, and so you've come out with this wonderful new book called Blue... Is it Blueprint or The Blueprint? Sorry, I forgot.

0:06:49 NC: Blueprint.

0:06:50 SC: Blueprint.

0:06:51 NC: Right.

0:06:52 SC: As I said, yeah, 500 pages. It has the feeling of a summing up of many years. We're both too young to have anything that is specifically, the culmination of our career quite yet, but it does have this synthetic vibe to it. So of course, what I'm going to ask you to do is to summarize it in 30 seconds or less for our readers. What is the point of the book? What's the elevator pitch?

0:07:14 NC: Well, I think for too long in my view, the social sciences and the biological sciences and the person on the street have been obsessed with the role of our evolution in shaping our propensity for bad things, our propensity for violence and tribalism and selfishness and mendacity. But equally natural selection has shaped us for good, has shaped... Has equipped us with capacities for love and friendship and cooperation and teaching. And I would argue that these qualities, these good qualities over the sweep of our evolution must necessarily have outweighed the bad qualities. If every time I came near you, you killed me or you were mean to me, you were mean to me or you filled me with lies, gave me fake news or information that was false about the world, then there would be no utility in my being near you and we would evolve to be solitary animals but we're not, we're social animals. So the benefits of a connected life must necessarily have outweighed the costs and the subsidiary ideas to that, there are a number of sort of motifs. One of those is that to the extent that these core features are good and to the extent that they have been shaped by natural selection, they give us a kind of a lever or kind of insight into our common humanity.

0:08:37 NC: The fact that humans around the world share these properties, we all do because we're all the same species, they are seen again and again in the of core fundamental universal, cultural, set of cultural universals which are A, universal and B, good. So it gives us a kind of an opportunity to empathize with each other and kind of address in some ways some of the forces that might otherwise divide us. These are modern political forces but that's not my main agenda. So those are some of the themes of the role of natural selection in shaping not just the structure and function of our bodies, not just the structure and function of our minds, but the structure and function of our societies. How have we been shaped across our evolution to manifest particular forms of social order? Why are those forms of social order universal? Why are those forms of social order good and what this is telling... And how do they become to be that way? So those are some of the big ideas in the book.

0:09:39 SC: Yeah, okay. That was more than 30 seconds but that's okay. There's a lot to pack in. That's perfectly...

0:09:42 NC: It's 500 pages, John.

0:09:45 SC: I know, but you gotta work on your... I live in Hollywood. You gotta work on your elevator pitch.

0:09:48 NC: Yes, yes. So it's Guns, Germs, and Steel meets better angels of our nature.

0:09:54 SC: Perfect, there you go. Now, I'm thinking about studio deals. Okay, good. It's a fundamentally optimistic book, right?

0:10:02 NC: Yes.

0:10:02 SC: And was it just because that's how the facts led you or do you think about it as coming into being within a milieu of other discussions going on and you wanna push back against certain trends?

0:10:15 NC: I would say both. I think that is where the facts led me. And there's no doubt that we've also been shaped for all kinds of awfulness. And every century, every millennium, every epoch is replete with horrors, warfare and pogroms and inquisitions and Holocausts and nuclear weapons and every other evil you can imagine, incompetent leadership that... So that's true and in many of those propensities of course, are also part of our nature. So part of it was my desire to focus on the good side, that is to say, I directed my gaze there but part of it as well, was the fact that I think there's so much evidence about this that hasn't been given the due it deserves and that also hasn't been seen to counterbalance those other qualities enough. So that's where I was coming from.

0:11:19 SC: No, I think it makes perfect sense. And just so, if anyone only gets to listen to the first 10 minutes of the podcast, I want them to get the take home message here. I think the central point of the book is what you call the social suite. Is that a fair thing to say?

0:11:36 NC: Yes.

0:11:36 SC: So this is a list of eight things that are both... Well, number one, you say, they're common to human beings in human societies. And number two, we're gonna attribute that commonality to evolution, to our genes.

0:11:50 NC: Yes.

0:11:50 SC: They're not just accidents of history, right?

0:11:52 NC: Correct and also very pertinently, they are specifically social qualities. So for example, I'm not discussing in this book those attributes of our human nature that we might manifest as isolated individuals.

0:12:03 SC: Right.

0:12:03 NC: For example, the way natural selection has shaped you to be risk-averse, or religious for instance, you could do those on your own. You could go through the world on your own. I'm interested in those things that we necessarily must express between ourselves. These things include things like love and friendship, social networks, cooperation, in-group bias, the preference of us versus them, kind of mild hierarchy and the practice of teaching and learning. And the eighth element is this capacity for individual identity, this ability that we have to express our individuality which very paradoxically, also lies at the core of our sociality.

0:12:43 SC: That's very good. You got them all. You didn't get them in the right order that you put them in the book, but you remembered all eight of them and summarized them very, very nicely. So these are characteristics that human beings have that play a role in our social world, as you say. And for the most part, they sound good, love and friendship and cooperation. There's a couple in there that don't, so we'll get to those. Is there a simple way of saying how you came upon this list of eight? Was it a whole bunch of things and narrowed it down or did you keep adding as you studied more things?

0:13:18 NC: Well, I suppose it could be like the standard model. You find... [chuckle] First you find neutrons and electrons and protons.

0:13:25 SC: We should say that you have physicists in your family, so...

0:13:28 NC: Extensive, yes. [chuckle]

0:13:29 SC: We can use the physics analogies all we want.

0:13:31 NC: Yes. Yeah, so we first, we find the electrons and the protons and the neutrons, and then we say, "Wait a minute, they are composed of quarks and subsidiary particles," and eventually we even get to anti-matter, so we got positrons, so we could keep going down and down. And I think, I suppose I would put this at the level of the first cut, so neutrons, protons and electrons. These are a complete set of things that I think can be used to define a social order as a first order approximation. Now, there are constituent elements in these things, which I allude to, but I don't go down and, you might even argue, are more fundamental. For example, I talk about empathy, but I don't include empathy as its own independent quality, and I talk about religion, for instance, but I don't include religious... Which we clearly have... Natural selection has shaped our religious capabilities, for example, but I don't include that because that's something you can express on your own, you could... So again, I narrow my gaze to look at these types of things.

0:14:41 SC: Speaking of empathy, I did have your Yale colleague, Paul Bloom, on the podcast, anti-empathy, and I bravely took on the pro-empathy side. Do you have a dog in that particular fight?

0:14:52 NC: Well, I think Paul is... He's wonderful. And...

0:14:55 SC: Yeah, we had a great talk.

0:14:58 NC: He's... His book is very provocatively titled, which... And ingeniously titled. He's not... He doesn't think empathy is bad.

0:15:07 SC: I know.

0:15:08 NC: I know you know, so it's... But it's very clever, because he does make an argument about the downside of empathy and why we... As you point out. So how did you do in your argument with him, in your debate with him? [laughter]

0:15:19 S21: Well, I clearly won. No, he admitted that I was right about everything. No, I think we had a very productive conversation. In fact, we disagree about very little, it's more a matter of emphasis than anything else. His next book is about cruelty, and I strongly urged him to call it "In Praise of Cruelty" to keep up that contrarian banner, but I think he's not gonna do that. Good. So as you say, you have an interest in both the social sciences and the natural sciences, and through your research and through study, you've come to this, the social suite, this list of common qualities that people have in their social lives, and that we can help to use these explain how cultures evolved, but there's an obstacle to being a good social scientist, which is that you don't have a human being version of the particle accelerator, right? You can't do controlled experiments quite as well.

0:16:09 NC: Or LIGO.

0:16:11 SC: Yes, exactly, or LIGO. You have neither observatories nor colliders. So what do you? You look at societies that exist, but of course, it's hard to find a control group there, but you have a couple of ingenious chapters on ways in which we've had more or less isolated experiments with human societies.

0:16:32 NC: Well, we do a number of things. First of all, in my lab we, and in many labs, of course, we do do experiments, frank experiments, and one of the things we've done is, we've written some software that's integrated with online labor markets, and we can recruit tens... We have recruited tens of thousands of people that come and participate in our experiments, and in a god-like way, we can randomly assign them to different treatments. And actually, this was very much motivated by my own background or education in the natural sciences. We take for granted... Many of us remember from high school physics the inclined plane experiment, where you vary the angle theta, and you put the weight on, and then you track how far it goes, and eventually, you learn about friction, and static and dynamic friction, etcetera, all the classic stuff. Or chemistry, where the teacher would sit in the front and titrate the red and blue, and you to get... Or in biology, you would dissect a frog and get a sciatic nerve preparation and electrical stimulation, see the muscles contract.

0:17:27 NC: And there hasn't really been an analogous way of doing that kind of pedagogy in the social sciences, so partly for research purposes, partly for pedagogic purposes, we have developed a kind of software that allows us to devise an experiment in the morning to... We call it Breadboard, because it's modeled after those other things many of us remember from high school where you would build electrical circuits on a breadboard with interchangeable components, resistors and capacitors and batteries, and flip the switch, the light bulb goes off, it's amazing. So our vision was that there would be interchangeable social components, you might manipulate the topology of the network into which people were placed, or you might manipulate the directionality of the ties, or the payoff matrix, or the information quality. How much noise was there in the communication, or the wealth endowments of the individual.

0:18:19 NC: So all of these social properties could be manipulated and you could create these artificial societies, and then experimentally change them and see what happens, consistent with theoretical predictions. So we've done a lot of that work, and that is in the book, but... But I kinda put the cart before the horse. Let me tell you, before the real experiments, some of the natural experiments, which is, I think, what you're asking about.

0:18:41 SC: I mean, I loved your real experiments, but the natural experiments are even cooler. [laughter]

0:18:44 NC: Yeah, the natural ones are great. Well, this is the thing, this goes back... We could have a bigger conversation about causal inference. I like to invoke physics models because it's often... People say, well, this work is sometimes... A criticism of some work in the social sciences is that it's sort of atheoretical, or it's merely observational. Well, Galileo discovering the moons around Jupiter was merely observational, and... Or they'll say, "This is observational, not experimental, we can't be sure." Well, astrophysics, there's limited experimentation in astrophysics. It's beautiful, complicated work that relies on observation, and theory, and computation, and... So those critiques in and of themselves, I don't think conceptually have much bearing, but I will admit that a lot of the work that's done is not a very high level or quality, but it's...

0:19:41 NC: The proper critique of those works I don't think is that they simply are observational rather than experimental. Anyway, so for experiments... So in an ideal world, at least from my mad scientist point of view, what we would love to do is take a group of babies that were acultural, that is to say, had no cultural upbringing or exposure and abandon them on an island and let them grow up and then come back 30 or 40 years later and see what kind of society did they make.

0:20:11 SC: Now we're talking. Now this is the scientific brain at work. Yeah.

0:20:13 NC: Yes, exactly, exactly. Exactly. This would be exactly the kind of experiment I would do if I could do it, is that, is this type of experiment. Now, of course, this is obviously cruel and unethical, but it hasn't stopped people from thinking about it for thousands of years. It's been called the forbidden experiment. But...

0:20:36 SC: So there's an official title for this. This is something that people fantasize about.

0:20:39 NC: Yes.

0:20:40 SC: At drinks at sociology conferences.

0:20:42 NC: Well, no, it's not drinks or like sociologists, it's monarchs. So Herodotus talks about an Egyptian pharaoh who was very interested in what was the first language that people spoke, what language was in our brains. It's actually an interesting question that a smart, powerful person might have thought of thousands of years ago. And so what he did was he took two babies and gave them to a mute shepherd to be raised up in the mountains to see what language did they make if they were never exposed to any language, obviously an awful, cruel experiment. And many monarchs... Yeah... But...

0:21:18 SC: But we get some data.

0:21:20 NC: Yeah, exactly. But some European monarchs also in the beginning of the 1100s and later also thought about this experiment. They framed it in more religious terms. What language did Adam and Eve speak? So they wanted to take babies and do the same experiment. And so it's been contemplated and sometimes allegedly done, but it's obviously forbidden. So instead what I look for some natural experiments, and one class of natural experiments was unintentional communities that were formed in the wake of shipwrecks. So a group of people who were, didn't choose to be, were just sort of grabbed and dropped on an island and who spent, who were at least 19 people I picked as a threshold and who spent at least two months there, and then what could we learn from what kind of social order they made. Did they cooperate? Did they have hierarchy? Did they befriend each other and did they teach each other things, for example? Were there divisions and what were the implications of the presence or absence of those features for the ability of the group to survive, for example, which is a nice objective function to the group, if you can get?

0:22:35 SC: And eventually some of them had to be rescued so that we could hear the results of these experiments.

0:22:40 NC: Correct. And in fact, there are some famous, very famous cases where... For example, my most favorite case... So yeah. So one further necessary criterion for this is that, yes, there can be a supernova, but the light might never hit the earth, and so we would never see it. So we would need... So we need one, at least one person to survive to tell the tale. Otherwise, we'd never heard of... We would never notice that this thing had happened. So... But one famous example where that didn't happen is there was a shipwreck where a large group of people... I don't remember the details at the moment, except I remember the crucial detail, which is they managed to capture some kind of huge bird, I think a petrel. They were in the South Pacific, and they attached to this bird's leg a message in a bottle, like a little capsule with a note identifying where they were, their coordinates, who they were, that they were the shipwreck crew of such and such a vessel, and they attached it to this bird, which the bird then flew thousands of miles and was found in Australia a few couple of years later, and the message was found in red, and an expedition was sent to actually find these men. And by the time the expedition got there, the men were all gone. They were dead. It was felt that they had somehow sailed to another island because there was no evidence of their bodies.

0:24:03 NC: So, obviously, we don't know what happened with that crew, but it's an amazing attempt to communicate. No, so we need someone to survive, and what I did was is there are about 9,000 shipwrecks between not ships lost at sea, ships that wrecked on a coast, between 1500 and 1900, and I found 20 of them that meet these criteria, at least 19 people living for at least two months, often for a year or more, and often larger groups, 50 or more people. And I got all of the old records through journals that they kept and also any modern archaeological excavations and try to get a sense of what do these people do, how do they organize their societies and... But that wasn't the only kind of evidence. I looked at the settlement of Polynesia, the Polynesian expansion when the ancient Polynesians spread out over the Pacific and populated all these islands. I looked not only at unintentional experiments but also at intentional experiments, at the communes in the 19th century where people set off to make a utopian community, and even since Roman times people have been doing this.

0:25:15 NC: They've been saying, "This society sucks. Let's go make our own society." And off they go. And in the 1960s and '70s there were communal movements in the United States, kibbutzes in Israel, or where I looked at settlements of scientists in Antarctica and the South Pole since the 1950s. The American station in the South Pole has had groups of scientists and technicians that winter over. So again, isolated populations have to organize themselves in some way. What do they do? And then...

0:25:46 SC: These are all made by people who of course come from our actual societies.

0:25:49 NC: Yes.

0:25:49 SC: So it's not the forbidden experiment quite but you're at least gonna ask how they might diverge.

0:25:53 NC: Correct. And they choose to be there. It's volitional. They're in culture. They're adults. There are lots of problems that make it not ideal as an experiment. But here again, I use some of the examples. You know I borrow some again some physics metaphors that the fact. That the... You know, the telescope that Galileo used was really crude, and yet he was able to see a lot with his telescope.

0:26:15 SC: Yeah.

0:26:15 NC: You know the absence of a Hubble doesn't mean that we should look down on a more primitive way of understanding or a preliminary way of understanding the world. So yes, there's light interference, an atmospheric interference and there's noise and our equipment is imperfect but we can still see something when we look at these unintentional and intentional communities. And the last thing which I mentioned earlier was I collected data about artificial communities either online worlds, like World of Warcraft or other massively multi-player online engaged with our own experiments or with the experiments of other scientists that have done these artificial experiments where they create groups and manipulate them. Including incidentally some of our groups where we replaced some people with forms of AI, bots, so we create hybrid systems of humans and machines and replace some people with programmable agents. And then we can really test what's happening 'cause we have complete control over that agent. So anyway, so you look at all of this evidence and then... Should I sum up or?

0:27:17 SC: Yeah, yeah, no, well... Yeah, I think we could...

0:27:19 NC: I have been talking too much.

0:27:20 SC: We could easily spend two hours just telling stories of these ship wrecks. So, let's just encourage everyone to buy the book.

0:27:26 NC: Yes.

0:27:26 SC: There's some great stories about shipwrecks in there. I mean maybe mention just the one island that had two ship wrecks on it at the same time.

0:27:34 NC: Yeah, I'll come back... I'll come back to that. Yeah, that's amazing. But just... But just to sum up...

0:27:37 SC: Just sum up.

0:27:37 NC: So then the challenge becomes so you have all of this data from different sources, but one way to think about this is to imagine a kind of a hyper space. Let's imagine it's three-dimensional space, where you can... You have axes that are defined by, for example, how large is a face-to-face community? That is to say, how much can each... How many unique individuals can each person befriend? And that number could go from zero to 1000. Let's say you can imagine a creature like ours that could have a 1000 real friends. Most of us have three or four or five real close, intimate personal relationships. And then you can imagine a society in which you array how cooperative they are. That is to say, on a one-off game how likely are they to get to cooperate with a stranger and that probability could go from zero to one. And then you can imagine a society in which another axis which defines how unequally is the wealth distributed in that society from again zero to one, all the wealth belongs to one person or all the wealth is equally shared let's say.

0:28:33 NC: So those like to be three or of course you could have more axes. And when you do that kind of an exercise and what you find is that all human societies that have ever arisen occupied a small fraction of that morphal space. They're all clustered in a little tiny region. And if you look at all the evidence from the unintentional and intentional and artificial societies, they all again and again manifest the same qualities. So there's a kind of universe... There's a kind of way in which we only manifest a small... It seems like a lot of variation, but it's actually not, in the small region of this space. And so then the question become, oh how and why did that come to be? How and why did natural selection constrain us to be just here?

0:29:16 SC: Is it easy to summarize what that space is?

0:29:19 NC: Well, it depends on... It depends on which axes you pick. How many axes you allow. I use some examples from other animals. I used examples... I borrow actually some of Richard Dawkins ideas from even older work in the 1960s on shell shape morphology. So if you're trying to get a set of mathematical equations that define all possible shells that could ever arise, it turns out we can summarize these shells with either three or 11 parameters... It's just... You couldn talk about that. It's too decay.

0:29:45 SC: These are the kinds of shells that snails crawl around in. Right?

0:29:48 NC: Yes, exactly, and you find that only certain shells that could ever potentially have arisen have arisen. And why is that? Is that because for example, it was impossible for natural selection even to give rise to such shells, or is it that there is no shell outside this cluster that is fit in any modern or any environment that has ever existed? And so the argument by analogy is that something similar happens with human societies, that there are no other kinds of societies that would make sense to make. And further evidence of that is in the book in that I look at animal societies like elephants and whales and I find that the social suite that we find in humans also is in elephants for instance. And in the elephants, you know that our last common ancestor with elephants was 85 million years ago. We have by independent evolution converged on the same solution. Just like two species might independently converge on an eye, we have independent... Because there's only certain ways you can make a camera type eye. Then we... To see the light we... There's only certain ways you can live socially if you're a mammal. And we find that again and again. Anyway do you wanna go back and talk about that one ship example or I don't know where...

0:31:09 SC: No, no, no, well, I think that... I just if it's possible, I get that there's this large parameter space of how the societies could have evolved and clearly the evidence is that we don't randomly fill up that parameter space. We stick to certain commonalities, and even the elephants stick to these commonalities. So there's clearly something beneficial and selected about some aspects of the social suite, the love and friendship and social cooperation and so forth. So the actual communities that you talk about though seem to at least on the face of it, turn out very differently from time to time. So is there a simple way of understanding what the commonalities are or it just that there's more than one way to be a society but still far fewer than all the ones we could imagine?

0:31:58 NC: Well, I mean I'm not sure I fully understand your question, but I think I did. So let me give two potentially just responsive answers.

0:32:06 SC: Please.

0:32:07 NC: So, one question you might... One way to restate your question is well sometimes they're mutants. Like your body is programmed to do certain things, to have a certain height or make insulin in a certain way and maybe you have a mutation that makes you not capable of making insulin. So you get diabetes and that's not as fit, let's say, for the environment in which we live. And... But that mutation is no more an illustration of the ordinary structure and function of the human body. That is to say, there's something that pushes you away from, let's say, the ordinary structure and this is a thing that's in your genes. It's biological. And of course there can be environmental things. So for example, if you have a group of children and you starve them, they don't grow up to have bodies... They might be actually more prone to diabetes in adulthood, and they might also have stunted growth, and in both of these cases, either the intrinsic let's say, mutation or the environmental constraint, we would not think of... We would say those have caused a swerving away from what was otherwise predestined to occur, that otherwise would have been let's say "normal".

0:33:20 NC: Now of course, I realize that sometimes these mutations actually are beneficial. In fact, that's how evolution works. But for now, I'm just computating this notion that there's something that could normally would occur, but in intrinsic or an endogenous or an exogenous reason, you've been pushed away from it. Well, the same argument I would make about societies. There's a kind of inborn society, but sometimes we're unable to realize that, for example if in times of scarcity, if there's not enough food in the environment, we might fall upon each other and eat each other. Now, we shouldn't do that. In fact, some evidence in the book suggests that if we cooperate we're more likely to survive. But I would argue that that's... The society that humans make in a moment of scarcity, that is to say when there is no food at all, is no more illustrative of the society humans would actually make if they had adequate resources than the body you make if you have been raised in scarcity is illustrative of the body you would make if there wasn't scarcity. So I'm trying to get at the kind of natural sort of innate thing you would have done without constraint.

0:34:32 SC: So when we talk about the island example, I think this is a good test case for these ideas where you had two different shipwrecks more or less overlapping in time, but they didn't know about each other [chuckle]

0:34:43 NC: Yeah, that was incredible. I got so lucky with that case. I think it's the only such case that I'm aware of, where in about 1846 there were... In the South Auckland Islands, south of New Zealand, slightly north of the Antarctica, there were two shipwrecks at the same time in the same place on this island, and they spent over a year there. One crew was almost two years, one crew was just over a year. And they overlap for about a year, and they did not know about each other's presence. There was some hint in one of the diaries that they saw some smoke in the distance one day, and they went to the smoke and they almost met. I mean, they almost met, I think.

0:35:22 SC: Did you ever watch Lost?

0:35:23 NC: I did. I saw a few episodes of Lost. Yes.

0:35:26 SC: You know it. That's what it is. [chuckle]

0:35:27 NC: Yeah. There was actually... There was Sean Carroll in a bunker underneath. You know, what?

0:35:31 SC: The others. [laughter]

0:35:31 NC: Yes, the others [laughter] engineering this thing. It's an incredible story. And they were different. They were very interesting and different. So, in one wreck, the Grafton. Actually the Grafton I had to relax my standards a little bit. There were only five members of the crew whereas in the Invercauld which wrecked on the northern part the island, the Grafton wrecked on the southern part. The Invercauld had 19 people. So the Grafton, the ship hits the shore in their foundering. And the captain had already been sick, he had a fever and he was in his cabin. And the ship is sinking, and other men make it to shore. And they have to decide what to do about the captain. So they set up a rope pulley system, and at great risk to themselves, they ferry the captain ashore. So this wreck starts with the saving of a life, where the people band together to save someone's life. And there are other...

0:36:29 SC: It's some sacrifice, right? Some altruism, yeah.

0:36:32 NC: With some... Some risk. Yes, some risk and some sacrifice. And there are other shipwrecks, not this one, where similar things happened where, for example, there's another case that I discuss where the captain had a big bag of gold in his cabin and the crew were trying to rescue the gold, and he told them not to rescue the gold, to rescue a girl who was drowning instead. And the gold was lost, but the captain acted this way, and I think that type of activity sets the tone, right, for the group to understand, "We're all in this together, we're gonna cooperate, we're gonna sink or swim." That's what happens on the Grafton. And in the Invercauld, the ship atomizes much more rapidly. There's also a slight difference in salvage and the other details of the two crews, that the Invercauld hits the shore and it's reduced to splinters within an hour, and 19 men make it ashore and they have a pencil, many of them they have no shoes, some of them arrived naked, this is a very common scenario that, the way that the crew would arrive naked literally on the shore. They arrive with a pencil, some matches which eventually dry, and they're able to light a fire a few days later. Although they screw up and they're trying to dry their matches by the camp fire and then they ignite all of them.

0:37:44 SC: Oh no.

0:37:44 NC: Yeah, so no. Total disaster. But they get their first fire going. And a couple of pounds of hardtack and a couple of pounds of salted pork. That's their salvage, plus some clothes. And one of the people was injured. And they're at the base of these cliffs. And they abandon this man. The other 18 climb up and sent an advance party up to find some pigs that had been previously set loose on this island by other people decades earlier, wild pigs. So they could see there's some food up there, and so 18 of them go and they abandon this man to die. And that's the beginning of the Invercauld. And ultimately, all five of the Grafton people survive and make it off. They sail away on their own. And only three of the 19 on the Invercauld survive. And they have cannibalism and they're routinely abandoning their weakest members. It's a totally different destiny.

0:38:36 SC: So, but what does that teach us about the discussion between the sort of determinism of the social sleek pushing societies in a certain direction versus the contingency of some influential event early on leading to later repercussions.

0:38:50 NC: Right. Well, it's again, I will just invoke the analogy of the body, that your body has a set up of... The DNA programs your body could be a certain way. For example, it might program you to be very hairy, but you might shave your hair. So there is an environmental thing that happens that makes you shave your hair. So that's... I'm really mad at myself and that's the best...

[laughter]

0:39:15 NC: That's the best analogy I could come up with on short notice. But... Or there's some cultures for example that bind people's heads like South American cultures, to reshape their heads so that the elites of this society were supposed to have a head that looked like a boat, it's called scaphocephaly. Sometimes babies are born in this way because the sutures of their cranium don't fuse, are prematurely fused and they get a oblong head. They thought it was very beautiful so they would bind children's heads to give them this really kind of alien-looking head shape. Now, that alien head shape is no more illustrative of the natural head shape than anything else, so I would say analogously to what were discussing the... Even though there is an innate type of society we are predestined or pre-wired to make, which resembles other social mammals too, incidentally, there are contingencies that can swerve us away from it, and those can include poor leadership, it can include profound resource constraints, although often we see paradoxically, one of the arguments I make in the book is that we are better able to meet our needs for food and water and shelter.

0:40:26 NC: It used to be thought that you had to meet those primary needs, first before you could manifest these more sublime qualities like love and friendship and self-actualization. But I actually think that in many ways, we have that in the reverse, that actually meeting our needs for friendship and cooperation first is what actually allows us to meet our other more basic needs for food and shelter and so forth, so... And I think there's good evidence for that. So anyway, so there can be contingencies that swerve us away from it, but I don't think those undermine the claim that there is a kind of basic core society that were pre-wired to make.

0:41:05 SC: Okay, that makes sense, and actually you intrigued me now. So what is this evidence that love and friendship need to come before food and water? [chuckle]

0:41:13 NC: Well, so that's again, just a laugh, buy the book.

[laughter]

0:41:19 SC: Buy the book. But we all know that's what's texting, sir.

0:41:22 NC: Yeah, exactly, exactly. So let me...

0:41:24 SC: We're not gonna run out of megabytes here, don't worry, tell us the story.

0:41:27 NC: Yeah, yeah. Okay, well, I'm just mindful, I'm dying to ask you all these questions about your own work and... But I took advantage of this opportunity and I feel like I know it's probably the point I'm being interviewed about the book, but...

0:41:40 SC: Right.

0:41:41 NC: Anyway...

0:41:42 SC: We'll get there.

0:41:43 NC: Oh, okay. So I guess the basic point that I would make is the following point, in a kind of broad high level answer to your question, which is our species, I think has one of the broadest ranges on the planet of any species, maybe even broader than ants, a particular species. And we have what EO Wilson calls the social conquest of the earth Why? Why are we able to live everywhere from the equator to the Arctic, from deserts to rivers? Some people are seafaring, they're people that literally never live on land, they spend their whole lives... I discuss them in the book, the so call sea nomads for example, they always live at sea and they forage for their food at sea.

0:42:28 NC: They literally hunt under water and they are the best free divers in the world. Actually, they've evolved in some ways in response to this, this capacity, but anyway, so why are we able to do that? The reason we're able to do that is because of our capacity for culture precisely because we evolve the capacity to accumulate knowledge across time and space and to distribute it across time and space so that, for example, a person born in the United States today in high school learns enough and can learn mathematics that would have made him or her the most sophisticated mathematician on the planet 500 years ago. Actually, as an aside, one thing that amazes me is that Isaac Newton invented the calculus at the speed in which we teach it, which is just mind boggling to me, you know.

0:43:15 SC: We're all amazed by that, yeah.

[laughter]

0:43:18 NC: Just unbelievable, right? The guy invents calculus in a year.

0:43:21 SC: Yeah.

0:43:22 NC: Just incredible. Anyway, so you are the... We are all the beneficiaries of all of this knowledge that has been accumulated. The roads and the smelting of metals and the agriculture, all the domesticated animals that our ancestors domesticated and the knowledge of the stars, and of navigation techniques and mathematics and actually that spreads across the planet. So it's very rare that someone makes a private discovery and no one ever else hears about it. You know its disseminated. And we'd like to disseminate knowledge and to learn from others where we've evolved to do this, so this capacity that we have evolved for culture is in fact what makes it possible for us to live everywhere in the world.

0:44:07 NC: So I guess what I'm saying... What I've gone on this long digression to explain that we are cultural animals, and that this equips us to live in many different environments is that that very variety that we privilege and that we see is actually a quality that we evolve to have that capacity to manifest culture and to be animals that teach and learn, and that's the more primary and fundamental ability that we have.

0:44:33 SC: Yeah, and there's a wonderful example you have in the book of the fact that human faces exhibit a lot more variety than faces of a lot of other animals. And part of that is how we identify each other, right?

0:44:44 NC: Yes. Well that's another kind of paradox. There's some paradoxes, when you think about human social living. The capacity to be individuals is itself lies at the core of our capacity to live socially so we have evolved the ability to signal our individuality, we do it with our faces. Every human face is different and the regions of our genome that are responsible for the shape and appearance of our faces are highly variable from person to person. Whereas the region of your genome that makes insulin is roughly the same. I mean, there are differences, but roughly the same, whereas the region of our genome that makes our faces is very different and gives rise to differently shaped faces in all kinds of ways. Furthermore, each feature of our face is uncorrelated with every other feature.

0:45:36 NC: For example, if you look at your hands, people with longer hands also have wider hands and there's like one parameter that is the hand size. Whereas, if you look at for instance the width of someone's nose, people with wider noses are not necessarily people with taller noses. Those two properties are uncorrelated in our face precisely because we want... There's many combinations possible of all the features of our face to give the most variety in our faces. And not only do we have this capacity, which is actually uncommon in animals and is an evolutionary luxury, we also have the cognitive capacity to tell the difference.

0:46:10 NC: So you can look out at a sea of faces and see that everyone's face is different, and this also is an evolutionary luxury. So both of these qualities, the ability to signal your identity and the ability to detect the identity of others are unusual among animals and are expensive or evolutionarily expensive. All this brain power that needs to be engineered to be able to do this thing. But they're essential for living socially, and the reason they're essential for living socially is you have to first be able to identify specific other individuals if you're to be able to tell who's a friend and who's an enemy or who is my child that I should actually give food to as compared to a stranger's child that I shouldn't necessarily raise or who cooperated with me in the past and I need to reciprocate their kindness. So we've evolved this capacity for individual identity, that is essential for our ability to live socially and we use our faces for that.

0:47:07 SC: For me, that was a little insight, a big insight I got from the book is one of these things you take for granted. Of course, I know different individuals and I have different relationships with different individuals, but may be elsewhere in the animal or the plant kingdoms for that matter, those differentiations are not quite as obvious. The idea of friendship and having a social network, you talk about it a lot in the book. Is it really that different between human beings and other animal species? Friendship?

0:47:35 NC: Well, it's very different. So first of all, many animals evolved to reproduce sexually so it's not uncommon that we form... And many animals also evolved to reproduce sexually with the same mate across time, to have a kind of monogamy. But we don't not just mate with each other, we befriend each other. We form long-term non-reproductive unions to other members of our species, and that's very rare. We have friends and that's rare in the animal kingdom, to have these sustained relations with non-kin, unrelated individuals. We do it, elephants do it, certain cetaceans do it, orcas, dolphins, certain other primates do it, it's very rare. Some people, they say, dogs, wild dogs do it, but that's not, they might, but it's not exactly right because packs of dogs often are genetically related, they're cousins and so forth.

0:48:29 SC: I was thinking when reading that part of the book, I certainly thought about pets, right? I mean, dogs and cats in some sense bond with their owners. Do they bond with their owners more than with other dogs and cats?

0:48:42 NC: Well, that's another whole topic. The domesticated animals and our friendships with those animals, which I actually give some examples in the book of that. And I think in some ways, what's happening there is our innate desire for friendship and sociability is being applied to and met by our relationships to these animals. Now often we domesticate animals that are quite social on their own.

0:49:09 SC: Right.

0:49:10 NC: So, horses live in herds and dogs live in packs and those animals already innately, even birds, flying flocks, those animals innately already have a sense of interacting with others, but not always, some people keep pet lizards for instance. And we do this, as I said, and certain other social mammals do it. It's not the same in the eusocial insects, so ants and termites and you know what, they're all clones, right? They're genetically the same. So it's not so special that one ant will help another ant, its identical twin.

0:49:44 SC: Yeah.

0:49:45 NC: It's much more difficult to provide an account for why we do that and we do. And the evolution of friendship is profound actually, and very interesting and it occurs, as I said, not just in us, but in certain other animals.

0:49:57 SC: And maybe from my extremely anthropocentric point of view, I think I'm surprised that friendship isn't more common in the animal kingdom. We take it so much for granted that we have different kinds of relationships with other different humans. It shocks me that it's not more similar in other, at least in mammalian species, let's say.

0:50:19 NC: Right. Well, it would have to... In order for it to evolve, it would have to meet a need, right? It would have to serve some purpose. And in part, you would have to have the availability of strangers, you would have to live in groups to start with, the first order criterion is that there has to be a group of animals. A solitary animal would be unlikely, let's say to evolve the capacity to befriend another solitary animal he occasionally ran into for instance. So you'd have to have first group living animals and then the further evolution of this capacity to form long-term non-reproductive unions to unrelated individuals. Again, it's not hard to explain, it was challenging, but scientists have done this. Why might you help your cousins? Well, there's kin selection and arguments from evolution why. The evolution of altruism towards your, even life-risking altruism towards your relatives make sense. But why would you willingly give to your friends? And there's a set of arguments about why that might be the case. One argument has to do with the fact that the evolution of the ability to help people in need when it doesn't cost you very much is very valuable.

0:51:38 NC: So if you think about what friends do for each other, we often do each other favors of different kinds or we help each other, we provide emotional support. And we do that in a way that is not strictly reciprocated. It's not like I'll scratch your back now, you'll scratch my back tomorrow, it's done in the sort of unconditional way. And that's an enormously valuable type of relationship to have in a social system, where someone is drowning and it doesn't cost you much to lower a branch to them so that they can be saved. This altruism to an unrelated individual could be extremely useful, if such a thing were to evolve. And so there's a set of ideas that John Tooby and Leda Cosmides have argued, correctly in my view, about the evolution of friendship, and Hruska as well, Donald Hruska also makes these arguments.

0:52:32 SC: Is there some relationship to language? It would seem to me that once individuals became better, more adept at speaking and communicating and agreeing and negotiating in more subtle ways, then it would become more useful to have a higher level of differentiation in our relationships between different people.

0:52:51 NC: I think there's probably a deep relationship between the evolution of language and the evolution of friendship, and actually even group dynamics. Some people have argued, I mean Robin Dunbar has argued, that our capacity for language evolved, in part, to be a kind of efficient oral grooming. So chimpanzees will groom each other. So one will groom the other, maybe they'll take turns or whatever, maybe they'll form a little circle, but it's all dyadic; you can only groom one other animal at a time. But a group of humans can sit in a circle and talk to each other. And I can give five people something of value, not just one person, using language. So it's a kind of... This transmission of information, it's a kind of grooming, a kind of way in which you could talk to multiple people at once.

0:53:53 SC: Okay. That's cool. And to study these... I do wanna let the audience know you have all sorts of little diagrams of networks in your book, The Social Networks. Because we did... I did a podcast with Steven Strogatz, who studies networks from a purely mathematical point of view. And so you've been able to uncover sort of things about the structure of friendship by these network diagrams.

0:54:16 NC: Yeah. Steve is a giant in the field. We use various sort of mathematical tools and analytic tools to map out these networks and trace out the topology of these graphs and summarize them and analyze them in the various sorts of ways. And there are a number of interesting properties that arise when you look at that; one set of ideas has to do with the fact that when you... Well, there's several ideas, let me write them down 'cause I'm worried I'm gonna forget them.

0:54:45 SC: Yeah. Okay, good.

0:54:46 NC: Properties of networks worldwide.

0:54:49 SC: You wrote a very long book.

0:54:51 NC: I know. And then I start... One of things that happens is, is that I get over excited and then I climb up a tree, and then I go out on a branch, and I go out on a twig, and then I fall off, and I don't know where the tree is any more.

0:55:06 SC: I know how it is.

0:55:06 NC: Yeah.

0:55:07 SC: Do you have a deadline for how long we can talk, by the way? 'Cause I have more questions.

0:55:10 NC: No, open-ended. No it's open-ended.

0:55:10 SC: Okay, good. Let's go.

0:55:11 NC: I'm worried that I'm being too loquacious and so...

0:55:14 SC: Not possible.

0:55:15 NC: Alright. Okay. So on the network... So when you begin to use these tools to map networks, you can make a number of discoveries. First of all, you can ask yourself the following question, which I think is still not completely answered, all though I am spending a lot of time in my laboratory trying to answer it, which is: You can imagine, let's say you have 100 people and you have the boundary conditions are a null set where no one is connected to anyone else, or a fully saturated graph where you have N times N-1 divided by two connections. And of course everywhere in between, you can have all these other possible networks, okay?

0:55:49 NC: Well, when you go into... And these these networks can have very interesting properties, mathematical properties. And you can go out into the world and you map networks, and you find again and again that human beings make a particular kind of network. And then you can say, "Well, why do they make this kind of network as compared to any other topology?" For example, human beings manifest something known as degree assortitivity, that is to say that highly-connected nodes are preferentially attached to other highly connected nodes. This is the opposite of an airport network. In an airport network, you have degree dis-assortativity. So, you have hubs, like Denver and Chicago and New York, that are connected to lots of small airports, but the small airports are not connected to each other. You can't fly from Lebanon, New Hampshire to New Haven, Connecticut. You have to go from Lebanon, New Hampshire to Boston and then from Boston to New Haven, or to Philadelphia or whatever.

0:56:39 NC: So degree assortative networks are networks in which highly connected individuals are connected to highly, so very popular people befriend popular people, and unpopular people befriend unpopular people. So you might ask, "Why do we do that?" Well, it's very interesting. It turns out that degree assortative networks confer on a population, a relative immunity to epidemic diseases. So in a degree dis-assortative network, if an epidemic, if a bio-terrorist strikes one city, in the next hop people will go from that city to Denver. And the next day everyone else in the whole country will be affected because people fly out from Denver. In a degree assortative network, if the epidemic begins at random somewhere in the graph, only if it happens to strike one of these few nodes that is high degree, will it spread to everyone. Otherwise, the epidemic will tend to be localized within a particular region of the network; for instance, among unpopular people, just giving the germ to the few other unpopular people, so it takes much longer for the epidemic to spread.

0:57:47 NC: So I don't think it's a coincidence that of all the ways we could come to organize our networks, we have organized them to have this property, of degree assortativity. I think natural selection has played a role, and this touches on very contentious issues having to do with multi-level selection and other topics, but the gist is: Of all the possible networks we could arrange, we have networks that have this property, and many other interesting properties. Like for instance, we have highly transitive networks, that is to say your friends are very likely to be friends with each other, much more likely than a random graph with a similar number of ties and a similar number of nodes. And this transitivity also confers certain advantages for group coherence and cooperation and so forth.

0:58:31 NC: So the first thing I'd like to say about these graphs is when you do these graphs and you mathematically summarize these networks you make a number of observations about the types of graphs people make from all imaginable graphs. And then I don't think it's a just so story. You observe that some of those properties that you can characterize have benefits and I think they have those benefits precisely because natural selection has worked on us to give us those benefits. First point.

0:58:58 SC: Yeah, I... Oh, that was your first point. Okay, let me make two little quick sub points. I know this is gonna be an expanding kind of...

0:59:04 NC: I've written down the other points, so I'm not gonna forget 'em.

0:59:07 SC: Okay, good. So here are my two little sub-points, one is I think it makes sense to me that the graphs like this are chosen by natural selection, but on the other hand, it's not obvious because maybe there's a physical making the graphs mechanism that naturally just easily leads to graphs like this and we're just lucky that it's also very useful. I would love to get evidence that points one way or the other.

0:59:28 SC: The second point is that the robustness of this kind of network structure I think is a wonderful lesson for human beings who intelligently design networks in computers or on the internet or in their electrical grids that aren't nearly as robust as the ones that nature builds. And it's often because you know we try to imagine what the threats are ahead of time and we're not very good at that whereas natural selection just sort of has put up with a whole bunch of unpredictable threats and generates therefore, a very generally robust way of dealing with them.

1:00:01 NC: Yes, I would agree with both of those points actually. And so, yes, do you want me to comment on them or just to say I agree?

1:00:09 SC: No if you say, "Yes," that's great then we go to number two.

1:00:13 NC: Yes, I would agree with those points. So that was the first point that I was making was about why we have this particular topology of all the possible topologies. The second point is that when you go out, therefore into the world and you map these networks as we have, and we've sent teams to Uganda, India, Honduras, the United States and various other places around the world, Sudan, when you map these networks you find that these networks, again and again, have a very similar architecture, a very similar topology. And I find that amazing, actually, that you can go all over the planet, and people befriend each other, and each person is exercising their pre-destiny to befriend each other. And then we assemble ourselves into this structure like ant colonies, like ant hills where we reproduce-ably make again and again this type of characteristic structure. So the second thing I would say is that first point is that we make a particular kind of network, second is we always do it.

1:01:09 SC: Yes.

1:01:10 NC: Within... There's some tolerance, but again and again we reproduce these types of networks. And the third thing I would say is that amazingly, other social mammals make networks with very similar topological properties. So earlier, we talk about transitivity the transitivity of elephant networks is very... Or dolphin networks is very similar to our own. Why should it be that the friend of a friend among dolphins is the dolphin's friend and a friend of a friend among elephants is the elephant's friend and a friend of a friend among humans is a human's friend? Well, because it serves a purpose. You know?

[laughter]

1:01:43 SC: Yeah.

1:01:44 NC: And it's clearly evolved independently because again, our last common ancestor was tens of millions of years ago and was a non-social creature. So I think these are all things of the all three of these points relate to the issue of the universality of networks and their function in our lives.

1:02:02 SC: Yeah, no, I think that it's a fascinating feature because it is one of these things where everyone investigating this is a human being, and therefore grows up as a human being and tends to take certain things for granted and it's amazing when we learn that things could've been different or didn't have to be this way. Speaking of which, there's not only friendship, but love which you talk about in the book and love seems different also, is also something that is at least more often human than in other animals. By love we mean sort of romantic attachment to your life long sexual partner, right? And I love the... I'd never heard of the fact that there are some societies that try to do away with it, that try to make reproduction purely about, or make sex purely about reproduction and not let you fall in love. And yet, as in Romeo and Juliet, people always try to get around that.

1:02:54 NC: Yes. Yeah, I mean love is... Again, another thing that's so interesting to me the... It's a uni-cultural universal. We love our partners, even in arranged marriages, so about a billion people live in countries that practice primarily arranged marriages. Many, many tens or hundreds of millions of people meet their... Only met their spouse once or twice before they marry them and go home with them and start having sex with them and raise a family with them and make a life with each other. And amazingly, when you use various metrics like the passionate love scale, or you look at divorce rates, divorce rates are lower in arranged marriages for a number of reasons, including cultural constraints. But...

1:03:34 SC: Yeah.

1:03:35 NC: But the sentiment of love, so even in those societies that have arranged marriages while love before marriage is seen as a threat and not, let's say the best way to organize how people should choose each other, love after marriage is very much seen as a desired property. Everyone thinks you should fall in love with the person I've chosen for you to marry. So this is a cultural universal too, this fact that we love our mates but you have to ask yourself why. We could be a species that reproduces without loving our mates, but we...

1:04:02 SC: Most do, right?

1:04:04 NC: Yeah, mostly just not in all species, so this is what we're discussing here is a kind of attachment that survives a single sexual encounter, a kind of sustained attachment which in our species we experience as love.

1:04:15 SC: Yeah.

1:04:17 NC: It's a kind of sentimental feeling and a emotional bond and a social bond to the people with whom we have sex. Now, not every person has it all the time. Of course, you could have sex about being in love, you could be in love without having sex, it doesn't have to be straight of course, gay couples love each other, and so it's not linked to reproduction in our species which itself is interesting. All of these things are true, but the core is that we love. We have this capacity to love the people that we are having sex with and... Or feel attached to them. And this is this type of social monogamy, this sort of sensibility is seen in certain other... 90% of birds are socially monogamous. They mate for life as it were. They become attached to their partners, and certain other mammals and it's seen universally in humans and I think it's very interesting.

1:05:06 NC: But as you said, there's some exceptions. So there's one... One people, the Na people in the Himalayas who organize their society, they have a strong cultural overlay like we were discussing earlier, the way certain historical contingencies can swerve you away from the innate, they have a very powerful over-language its organized to prevent couples from feeling affection for each other and for example, it's not uncommon for women with a matrilineal society, the men will go trawling for sex in the evenings, the women will stay at home, the young men and older men will knock at fences, and say, "Have sex with me tonight. Have sex with me tonight." The woman will make her choice, she'll say, "Okay I'll have sex with you." And they might have a kind of a fleeting relationship for a number of days, or weeks, or a year, but she could have more than one at a time, if she wanted.

1:05:57 NC: And the boys that are rejected, they are not supposed to feel rejected or jealous their friends will mock them, they'll say, "There's another girl in the other village or down the street," why are you feeling this way? You shouldn't feel attached stop it. Don't feel attached. Just go have sex with someone else."

[laughter]

1:06:13 NC: And there's mockery of people who have sexual jealousy and it's not uncommon for women in these villages to have had sex with every other man in that village or every other village of their cohort for instance. Now in this... But even in this society, some couples, for them the forbidden fruit is to be in love. And they will fall in love and say, "We're running away to be in love to just be together. Just the two of us."

1:06:41 SC: Crazy rebels that they are.

1:06:42 NC: Yes, crazy rebels that they are, exactly. Its like I just don't wanna have sex with you, I wanna be I love with you, I wanna spend my life with you. And they can't help it. So... And this is, to my knowledge, the only society that's organized this way. And Marco Polo writes... Encountered it, and writes about it. The Chinese Communist Party thought that this licentious behavior was sapping productivity and needed to be stamped out these bourgouise values.

1:07:07 SC: Yeah, they would think that yeah.

1:07:09 NC: Yes, and they tried to stamp it out, but they couldn't. Anyway, they still practice. They still have this type of traditional order among the Na.

1:07:17 SC: So is there... Given, the social-suite that you talked about your eight factors one of them is love. Is there a particular explanation? I know there's always a danger of these just-so stories, but can you come up with a theory, at least, as to why love goes along with these other properties that are... Seem not maybe uniquely, but especially human.

1:07:42 NC: Well, we don't know exactly why we evolved the capacity for love. The leading candidate is that attachment of... The attachment females feel to their male partners and males feel to their female partners because most of the evolutionary force was acting on heterosexual unions, that capacity must have served a purpose, and one set of ideas has to do with enhancing the prospects of survival of the offspring.

1:08:12 SC: Yeah.

1:08:12 NC: That children have better likelihood of surviving especially in a highly cultural animal like ours that needs to be taught when the parents stick around, when both parents stick around. Now we're not the only... You know penguins do the same thing by the way. So we're not the only animal that has bi-parental care but attachment seems to be essential for that to happen. The male needs to feel like that any contributions he's making to the rearing of these children are his and one way to do that is by the female of the species telegraphing I'm attached to you. In other words, if you see that I love you, you know these are your children, your offspring.

1:08:52 SC: But as soon as you say penguins do it too, that sort of gives the game away because there's thousands of species out there, and it's not like they mostly do it it's like we have to kind of go pretty far in the evolutionary tree to find others that do it the same way.

1:09:05 NC: Yeah, well 90% of birds mate for life, so it's very common in the birds.

1:09:09 SC: Okay, that's better.

1:09:11 NC: Yeah, but it's very uncommon in mammals, incidentally. And also, I should I be very careful to emphasize that what's important here is the attachment not the number of partners.

1:09:21 SC: Sure.

1:09:21 NC: So for instance, so polygamous and polyandrous societies also have love.

1:09:27 SC: Right.

1:09:28 NC: So it's not about having one partner, it's about the extra feeling you have about the partner you're having sex with.

1:09:36 SC: Yeah, it's not purely reproductive.

1:09:38 NC: Correct.

1:09:38 SC: There's some emotional attachment as well. Yeah. Well, okay, so these are the good aspects, we've talked about friendship and cooperation and love. Now, among your eight factors in the social suite, there's one that is in-group bias, and there's another one that is mild hierarchy. So you say mild hierarchy so you're both... You want your little hierarchy, but you want your cake and eat it too. You're not too much hierarchy, right? How do you fit these two factors in which might seem a little bit less obviously peace and love and understanding in with the other ones?

1:10:14 NC: Well, even these qualities which superficially might seem to be disadvantageous like this in-group bias, for example, this preference we have for us over them, which is a human... Which is innate. It's part of our nature, it's a universal it's actually very depressing to me that we are this way, its part of our nature, even this quality has evolved in order to support our capacity for cooperation, so...

1:10:44 SC: It is one of the most robust psychological findings, right? Like... I think that you mentioned in the book, and there's also a study that came out very recently where you give children completely arbitrary markers of you're in this group and you're in that group and instantly, they favor the people in their group not the other one.

1:11:02 NC: I know, it's really depressing, isn't it. You can randomly assign children to t-shirts, three-year-olds to a blue and a green T-shirt. You can test that they know that it's chance, They recognize that it's not... They didn't do something to deserve this color and nevertheless, with this still called Minimal Group, this is called the Minimal Group paradigm. You can elicit from them, oh those green shirted children they're awful, they should be punished, they shouldn't get any toys. It's awful. It's an awful...

1:11:31 SC: Screw those guys. Yeah. Exactly.

1:11:32 NC: Yeah, exactly. Its an awful... It's just an awful part of our nature, honestly.

1:11:38 SC: But it's kind of a... I think your argument is that awful-ness is kind of a spandrel, is kind of a side effect of there's a goodness, there's a usefulness to this in-group bias.

1:11:46 NC: Yes, that's exactly right. And that it has evolved to support our capacity for cooperation. It's not the only tool that has evolved to support our capacity for cooperation, but it's important one. So in a way this in-group bias is a tool to reduce the scale. So imagine you have a large population here and then in the middle level you have groups and at the bottom level you have individuals. So top level you have a huge population, middle level you have groups, us and them, in the bottom level you have individuals. The capacity to draw the distinction between us and them is gonna be essential to reduce the scale of the people you need to cooperate with. If I put you in a large group and say, "Cooperate with everyone," it's very hard for cooperation to evolve and for you to practice it. But if I say, "Just cooperate with your group and you don't have to co-operate with everyone else." Actually it makes it easier for cooperation to evolve in that type of a situation.

1:12:43 NC: So one of the theories about the evolution of xenophobia or parochialism or in-group bias, is that it makes it possible for us to cooperate with each other. But I should say that it's not the only thing, the evolution of friendship also meets that need. 'Cause if you think about friendship, what friendship does is it adds structure to a population. So instead of a well mixed population, instead of having everyone is randomly interacting with everyone else, a network imposes structure so each person is interacting only with certain other people but everyone has their own alters. Everyone has someone they're interacting with. And now I just tell you cooperate with your friends. Everyone was co-operating with just their friends. And so it reduces the scale by adding structure to the population.

1:13:26 NC: And so that's another way to get cooperation but in-group bias is one of them. And it is... It is a depressing... I mean it is one of the most depressing things that I have to think about because... Because why... You know why can't we just have indifference to the out-group. Must we hate it? Why can't we just love our own group? Okay, fine, we'll let you love your own group but you don't have to kill the other group. Why should you just let them be or even...

1:13:55 SC: Well, we're recording this podcast in the midst of the NBA playoffs and as a Sixers fan, I can tell you that Celtic fans are just not as morally good as Sixers fans, it's just empirical finding. But is also...

[chuckle]

1:14:09 NC: Yes, but do you think they deserve to die. I mean would you launch a war against them?

1:14:15 SC: No, you know I wouldn't kill them, but if they were in distress, I might not go all out of my way to help. That's all.

1:14:21 NC: I can see that.

1:14:22 SC: But this is also something where maybe this is the time when it is worth mentioning that we can talk about innate tendencies and things that make us human, but we also have the cognitive capacities to overcome them. We can think about how to shift our in-group biases and change the focus as to where we put our locus of care. The expanding circle.

1:14:46 NC: Right. So I think the way I would say it, the way I would argue about that is, yes that's one tool at our disposal is just to use our brains that we have been endowed with to say, "Okay, this is a part of our nature, but I have agency, I don't have to do this thing." Correct, but there's also other tools that we could draw on. So for example, earlier when you imagined the three-level model like the large population, the sub-groups that are defined subset, and then the individuals, one thing we can do is you can go up a level and you can use the capacity that we've been endowed with to draw the boundaries. These are artificial boundaries, in our groups. We say us and them, we said like the T-shirts is an artificial boundary. And instead what you can do is you can... Or language or religion, these are artificial boundaries. You can go up a level and you can re-define the boundary to be the whole group.

1:15:37 NC: And if you think about the American project for example, if you think politically about what ails our society today, there's a kind of over-identification of groups and the kind of suspension of a commitment to the American project. And one of the things that's amazing about our society is that anyone can be an American. We say if you come to this country, it doesn't matter whether your ancestors were Greek or Irish or Indian or whatever, you can be... You are an American. You just have to accept our political principles, the Bill of Rights and our Constitutional Government and you can be an American. Other companies don't necessarily do this by the way, it's very difficult become Swiss citizen for example or a Japanese citizen but you can become an American.

1:16:18 NC: And so this has always been a part of our society, de Tocqueville talks about this extraordinary thing and what it is in essence is E Pluribus Unum, you go up a level and you say, "What really matters is we're all American." I think that one of the reasons we have ascendant tribalism in our society today is in part a side effect of the collapse of the Soviet Union. I think when we had... When we were all united against the common enemy, I think there was a bit more solidarity in our society. Yes, of course, we had political differences, and I'm not saying it was the best of all possible worlds or... But I think it's not a coincidence that this recrudescence of tribalism in our society at this historical moment follows closely on the heels of the lack of another superpower that we're kind of trying to countermand for response.

1:17:09 SC: So what we should be hoping for is an invasion by aliens...

1:17:12 NC: Yes, yes, I think...

1:17:13 SC: So that all of humanity could come together.

1:17:14 NC: Yes, I think that would be terrific. For our common good. The problem is, those aliens, I'm quite convinced... Actually, I'd love your opinion on this. I think those aliens would be just very likely to wipe us out. I don't think they'd be beneficent. What do you think?

1:17:28 SC: Yeah, there's... Well, the way that I would put it is, we have no idea, but if there's a 5% chance that they would wipe us out, is that a risk worth taking? Let's put it this way: We have a very good idea that they could wipe us out.

1:17:40 NC: If they got here, yes.

1:17:41 SC: Yeah, the chances, if we meet any alien civilization, that we would be able to put up a fair fight are negligible, so I would rather see the human race try to figure stuff out for themselves for a few more 100,000 years before we meet the aliens, personally.

1:17:56 NC: Yeah, I'm inclined to agree with you. Leaving out the fantasy that, in a "War of the Worlds" situation, they would be infected by our bacteria and be wiped out, I think, much more likely, a species that could reach our planet would treat us with the same indifference that we might stomp on an anthill if you cross an ocean to go to another continent, or frankly, that we saw with the colonization of South America, right? The indigenous peoples were just wiped out by the Spaniards, and so... With just indifference. So I think...

1:18:31 SC: Well, to be fair, there is a counter-argument to that, which we should put on the table, which is that maybe...

1:18:36 NC: They would evolve to be beneficent?

1:18:39 SC: We don't know, again, but... Well, maybe there's a threshold that species cross into self-awareness, a certain level of cognitive capacity and consciousness, where they can use language and have technology and so forth, and once you reach that, you have a certain empathy and fellow feeling for all the other species that feel likewise. Now, maybe not, right?

1:19:06 NC: How are we treating the elephants on our planet?

1:19:09 SC: Well hopefully, we're getting better. We're terrible, is obviously the answer, but maybe we're getting better. All of these things are happening on such a rapid time scale that if we're trying to ask questions about what we will be doing 1000 years from now, it's almost completely hopeless, right? So I'm not saying we have figured it out, but I'm saying that there is a logical possibility that we are in the process of figuring it out, and by the time the aliens get here, they will have figured it out.

1:19:34 NC: That's what I used to think, and I would be happy to follow your lead in thinking what you're saying, but I... Increasingly, I'm getting more aware... We're on a tangent of a tangent right now, but I get more worried about... I'm sort of buying Stephen Hawking's argument a bit more than I used to about this topic.

1:19:56 SC: And you're the one who just wrote a 500-page book about optimism. [laughter]

1:19:58 NC: Exactly. Okay, but hold on. So we were talking about groupiness and collective identity, but there's another technique that evolution has equipped us with, which often is overlooked, and that's the capacity, not to step up and take advantage of our ability to define groups, but to step down a level to the level of individuals. And so here, the idea is, we have faced the tribalism, not by expanding the the boundary, but by decreasing the boundary down to the individual level. What we say is that you should treat each other person as an individual. Earlier, we talked about how we have the capacity as an animal to uniquely identify every other person, and this too has been a part of our culture and our society. It's actually at the root of what Martin Luther King argues when he says he looks forward to a society where we can... People are judged by the content of their character rather than the color of their skin. He's saying each person should be judged as a person, not as a member of a group, and this also is a tool that evolution has equipped us with, and as it turns out, in my view, provides an avenue out of the tribalism that is afflicting us today.

1:21:02 SC: Yeah, good. That's a whole long... Maybe for the next podcast, when I have you on next year again, we'll discover some of these, 'cause there's so many other things I wanna get to. The hierarchy question. Mild hierarchy is one of your elements of the social suite. So this seems to suggest that, on the one hand, human beings like to have a little bit of hierarchy, but not too much. Is that a fair gloss?

1:21:27 NC: Yes, and again, you have to ask yourself why we evolved this. There's... I need to scribble some notes, so I don't go off the deep end again. So, why do we have mild hierarchy? Again, you can imagine a parameter space of hierarchy, from complete absence of hierarchy, when everyone is absolutely equal with no differential resources or power, let's say, to a complete autocracy, where one person can completely dominate other individuals and kill them at will, let's say. And we are in the middle regime, it turns out, as a primate species, and we have involved this capacity for mild hierarchy. And mild hierarchy is important, because both extremes are bad for us, and they're bad for us in rather specific ways.

1:22:20 NC: First of all, in the absence of any hierarchy, turns out that there's some experiments that have been done by Jessica Flack at Santa Fe and others, where they've taken primate species, they've mapped their networks, they've identified the top dogs, or the top primates, and they have experimentally removed them from the network. What they find is that chaos ensues. There's a tremendous amount of fighting as people jockey for power and position, even among the subordinate, peripheral individuals. So one of the things that a little hierarchy does is, it tamps down on violence, it keeps the peace, it keeps people from fighting with each other. In addition, there's some evidence that a little bit of hierarchy, and here now, I'm meaning when there's popular individuals, when some people are popular, regulates the flow of information through the graph, and optimizes the flow of good things and suppresses the flow of bad things. So...

1:23:16 SC: You're saying that Walter Cronkite was better than Twitter for spreading news around.

1:23:18 NC: Yes, actually. That's a really good example, approximately. But yes, that's right, that if there's some kind of central filter in the information, so for example... That this helps keep the peace. So there's some evidence of this role of mild hierarchy, but in addition, we humans have evolved two different ways of communicating status. There's two different kinds of ways you can think about hierarchies or sort of status in a society and one of them has to do with dominance hierarchies. And many animals have this and this has to do with the ability, typically physical ability, of bigger animals to impose their will on others, the sort of dominance hierarchy.

1:24:01 NC: And you can think about these as costs, the costs that one animal can impose on another animal, so the animal with bigger antlers or bigger tusks, for example, can kill or drive away the other animal. And so, subordinates in those types of hierarchies try to avoid the superordinate state because of the cost the subordinates can impose on them. But we humans have a parallel kind of hierarchy which is based on prestige, and prestige hierarchies have to do with the benefits that superordinates can impose on subordinates, and because the superordinates let's say have knowledge, we are smart. So your graduate students, I'm assuming, want to spend time with you because of the benefits you can confer upon them, I'm assuming.

1:24:43 SC: So they believe. They don't know, don't tell them, but yeah.

1:24:47 NC: Rather than avoid you because of the cost that you can impose on them. These are prestige hierarchies and in our species, these often have to do with cognitive abilities. We can teach each other things. So we have two parallel ways of having hierarchy in our society. Roughly speaking, the costs, which often are physical and the benefits, which often are combinant that we can distribute, and there's evidence for both in our ancestral, in our evolution, but it's because of this connection to prestige that mild hierarchy can be beneficial. The existence of people with special knowledge that can distribute these benefits to others is part of the reason you want some of the mild hierarchy. Now when you get too much, what typically what we feel has happened, what's likely to have happened, we're not sure, is that subordinates probably resented too much power going to some particular individuals and probably banded together and killed them, actually. And so one of the reasons we think in our evolution, we've been shaped for a mild hierarchy is precisely for this reason.

1:25:52 SC: Yeah, so is it seems as if, I'm going to guess and you'll correct me if I'm wrong, that the thing about mild hierarchy is it is the best system for various reasons and therefore maybe it explains why we evolve to like it. Obviously, there are examples in history where we've gone to complete autocracy and stratification or complete anarchy and egalitarianism, but there's some happy middle where you're gonna argue that we tend toward.

1:26:17 NC: Yes, that's what I would argue and that there's evidence from other social mammals that this is optimal including experiments with primates, so that's right. And it often has to do with social animals that have the capacity for teaching and learning that can collect and distribute information, that you get these kind of counter-balancing forces. So basically, instead of having organizing the society around the dominance hierarchy now all of a sudden, you need to reduce the ability of physically very powerful individuals to dominate. And let's see how to put this exactly. It turns out that one of the reasons it is felt that we have mild hierarchy is that there's been a kind of rough justice, a kind of rough calculus between dominance hierarchies and prestige hierarchies and that's why we wind up a little bit in the middle range as I talk about in the book.

1:27:13 SC: That makes sense. All of these features of the social suite from identity, love, friendship, hierarchy and group bias, you wanna say they're not only there, but you wanna say they're genetic, that they're built into our DNA somehow. Is that mostly sort of circumstantial? What else could it be if it's that universal or is there something, is there more directly genetic evidence that we can point to for the origins of these features? That sounds like something that would be very difficult at this point in human history to really establish.

1:27:46 NC: Well, no, for some traits there's quite a lot of evidence. My lab has done a lot of work on the genetics of friendship for example, and we've been able to show that the propensity for friendship, some of the higher order structures we were discussing earlier, are partially genetically encoded. There's no doubt a role for culture also and nurture, but there's clearly a role of nature. We've shown that the way you choose your friends is partly shaped by your genes. You might be able to reason by analogy, and see, for example, many people are capable of love at first sight. It's not an uncommon phenomenon. You should have the intuition that that love at first sight probably has something to do with genes. That is to say that some kind of optimal partner choice should be under selection is not a shocking claim and there's a lot of evidence for that in the animals, for example. We do experiments for that, but I would say friendship choice also is under natural selection for analogous reasons and we have evidence for this, and so there's evidence for that. There's also evidence for a partially genetic basis for attachment, for love.

1:29:00 NC: There is surprisingly little evidence so far that we've been able to adduce, for the genetics of cooperation in our species, but we do have some such evidence in other animals. So it's again, doesn't scream credulity to me. So, we have information on the level of genes using a variety of approaches, that provide evidence for this, plus there's the comparative phylogenetic approach where, for example, we find similar properties seen in other animals or we can trace it out across evolution, so we can say when did social monogamy appear in our species? And we see a very specific historical evolutionary moment when that occurred, and we can trace out the branches, and this type of evidence also is evidence so there's lots of convergent evidence that supports the claim that many of these qualities are shaped by natural selection and partially encoded in our genes.

1:29:53 SC: But we're not at the point yet where we could actually point to a place in the genome where this is a preference for mild hierarchy or something like that, right?

1:30:03 NC: No, and in part because these traits are so complex, we cannot even do that with height or schizophrenia risk. And increasingly we're seeing that many of these complex traits are polygenic. So the kind of thing we all learned in high school biology about sickle cell disease or thalassemia being monogenic mutations that follow Mendelian inheritance, those are the exceptions actually. Most of... Forget most of the behavioral and complex traits we manifest. Even a lot of the physical traits like your schizophrenia risk or your diabetes risk or your height also are polygenic that we barely understand... We know there are hundreds, a couple of hundred genes that are responsible for height. We know height is very heritable, but only 1% or 2% of the variance can be explained by known genes, so something else is going on and that's being worked on very actively.

1:30:56 NC: I think in our lifetimes we're likely to know the answers to some of these questions. I think it has to do with the combinatorial complexity of the genes, that is to say, it's not about which genes you have, it's about how they interact with each other. And furthermore the temporal unfolding. So, you might have five genes, each of which has two variants. The precise sequence at which they turn on and off might determine how tall you are, even if you have the same variance in a given individual and we don't know anything about that yet. We know some about it, but we're learning more about that.

1:31:25 SC: Yeah, I think it's just important to emphasize 'cause lot of people hear that something is genetic and they think, "Oh, there's a gene for it and we'll find the gene and... " We both know and I think probably most of our listeners know it's way more complicated than that. And so that you can have good evidence that something is heritable, as you say, without having any idea where it comes from in the DNA.

1:31:44 NC: Yes. Like the facial... Like for example, I'll give you an interesting thing we're talking about facial morphology, there's one of those famous examples in Evolutionary Biology of something known as an adaptive radiation, which is from an original species, how many other species evolved to fill in various niches is Darwin's finches, right?

1:32:04 SC: Right.

1:32:05 NC: So he looks at all these beaks and he sees that different animals have different beaks depending on what kind of food is available on the island with those finches, from an ancestral population of finches, the finches on this island evolved to eat nuts and the ones on this island to eat flowers and they all have different things. And just recently, I think it was published in Nature like a couple of years ago the genetics of this was worked out so we actually know what are the genes that have variants that affect the shape of the beak in these animals. You know something? That same gene affects our faces [chuckle] and there's evidence that that same gene plays a role in facial morphology in humans. And I think I had the footnotes to that in the book. So I think we will find, for example, increasingly the genetic evidence for some of these qualities, including, for example, the individual expression.

1:32:58 SC: What do you think are some of the... We are winding down here. So what are some of the normative implications of what you're saying? You have a brief section in the book at the end where you talk about morality, for example. And I think this is a place we're gonna disagree because you seem to be more sympathetic than I am to somehow extracting some moral lessons out of the facts about who we are and how we got here.

1:33:24 NC: Right, so moral philosophy is an attempt to provide a kind of building up of moral principles from axioms like Euclidean geometry, we start with seven axioms. I think it is, I can't remember. And you get all of Euclidean geometry from some parallel lines, continue indefinitely and some blah blah. But the moral philosophers have been working for at least 50 years, maybe more. And they have yet to uncover what these universal, you know, what these fundamental axioms that are universally applicable are. And it's clear that Moral Philosophy cannot be... It's not about voting, right? You don't like have everyone vote what's right, we know horrible... Things that we would consider to be grossly immoral like the killing of autistic kids in Nazi Germany. Where everyone thought that was fine and but you and I would look at that and think that's just clearly immoral. So it's not about the majority rule, or might make right, it's not about a majority rule. Otherwise, the Cardinals would have been correct and Galileo would have been wrong. So that's not what determines whether something is right, is how many people believe it.

1:34:43 NC: It's not determined by who... Whether powerful people espouse it. So there's a sense in moral philosophy that there must be some kind of outside of human ways that we could come up with developing these moral principles. Now I am skeptical actually that that project will succeed for a number of reasons. And here I share Churchland's perspective, the philosopher, but I do believe that biology can help guide the way as I argue a little bit in the book and here I borrow some ideas from philosopher Philippa Foot where she very famously says, "In moral philosophy," she said, "I think it's helpful to think about plants."

1:35:25 SC: [laughter] Which makes you think, yes.

1:35:27 NC: Yes, I love philosophers. It's just incredible, you know. You're like, "What the hell does she mean by that, exactly." She goes on to explain that when you think about plants you can think about whether a plant has good roots. And she says that you can speak of this plant has good roots or bad roots. And what are good roots? Good roots are the roots that make it possible to be a plant. And she also uses the example of clocks, she says, "You can speak of a good clock or a bad clock." And she says that a good clock is one that tells time. A bad clock does not tell time. So she makes an argument about how while much of morality is very contingent, eventually slipping and sliding, it meets reality, it meets a kind of foundation and that there are... You can develop moral principles against constraints, you can speak of something that is good or bad given the constraints, condition on the constraints. And so, this is in essence what I argue about human societies. Given the need for us to live together, given that we are social animals, what equips us with that? And that's what makes it good.

1:36:37 NC: So our capacity for love is good in that sense. Our capacity for friendship is good in that sense and I can't help but notice that many of these qualities are good in the every day meaning as well. If you ask people... We don't care if you love yourself, or are kind to yourself, or are just to yourself, we care whether you love others, or are kind to others, or are just to others. Our virtues are social virtues primarily, and so we clearly have a connection between that which we think of as good, a good life, or good practice, or good behavior. Much of that, not all of it, 'cause we also, for example, can think of bravery, facing a violent animal, for example, so it's not social, but we can think of that as a moral virtue. Most of our virtues, many of them are social in nature. So that's sort of the argument that I try to make at the end of the book, and why I think that it is possible to provide at least a partially biological foundation for morality.

1:37:40 SC: Yeah, so I would... I think what you just said is extremely clear and understandable, and I don't quite go, I'm not quite on the train, and the reason why is 'cause I think it's very important to draw a distinction between meta-ethics or meta-morality. I don't know why people don't use the word "meta-morality," but what are the foundations of morality that give its foundation its oomph or whatever, versus morality and ethics themselves. Like, okay, so what are the morals that we pick?

1:38:07 SC: I think that biology and the constraints that get us here and the goals that we have as both individuals and social creatures clearly are going to have a huge impact on how we decide to actually be moral, what counts as being moral, etcetera, but the foundations of morality, that doesn't follow from those constraints or that biology. You can always choose to be very different and no one can say that you're wrong in the same way that they could say you were wrong if you were wrong about something scientific or logical. So I would like to encourage the world to just relax and accept the fact that morality doesn't have an absolute foundation, and nevertheless, we have enough shared concerns and shared desires that we can construct a way to live that seems to us to be moral.

1:38:53 NC: I wouldn't disagree with that, I would sign up for that. I have to understand more about how you were framing the distinction between meta-morality and moral rules because, if anything, initially, when you were expressing it that way, I would have said that the biology could provide a foundation for the meta-morality and the culture or history would fill in the specific rules. So for example, not killing strangers might be something that natural selection might have shaped, but who counts as a stranger might be something that's very culturally specific, or...

1:39:26 SC: Yeah. So to me, both of those are morality. So morality is that Killing strangers is bad, meta-morality is, why do we say that killing strangers is bad?

1:39:35 NC: I see.

1:39:35 SC: Where's the warrant? What is the justification for that?

1:39:38 NC: I see.

1:39:38 SC: And rather than being moral realist, whether it's Kantian or otherwise, I just wanna be a moral constructivist and says, "Well look, we all think that, let's figure out how to live it."

1:39:48 NC: Okay, so there... I get the point. So there are some arguments that evolutionary biologists have made, like Bret Weinstein and others, that actually, the... What has evolved is not the content of moral rules, but even the capacity for moral deliberation. In fact, the argument is that what matters is that we evolve to argue with each other. That serves a purpose, it binds us together. The fact that we, for example, don't fight, don't kill each other, necessarily, as a first instance, we just argue, and that we might come to different conclusions, different groups of people endowed with the same capacity for argument might argue a lot, and then, at the end, come to different conclusions, but the fact of arguing actually is what's giving an outlet for otherwise bad inclinations, and also binding us together by giving us something to do.

1:40:44 NC: So some people have even argued that the very capacity for moral deliberation is itself an evolved property that we have. So I understand, I think, what you've said, and I don't think it's crazy, but I still think that you could be more charitable. I think you're probably right...

1:41:05 SC: No, I'm in a plucky minority here. I think most people don't agree with me, including most professional philosophers, but it's just a matter of time...

1:41:11 NC: Before they come around.

1:41:13 SC: I do think... Yeah, the words that you're using, it's very similar to communicative rationality, Habermasian way of thinking about how human beings interact and how we come to things. And I think that we have, I even want, in my less charitable moments, to say that this is a relic of our religious upbringings, the fact that we want to find this absolute bedrock, logical geometric derivation of things, rather than just saying, "Hey, let's come together and agree about it."

1:41:44 NC: Yes and no, I would say to that. I would say there's no doubt that modern moral philosophy owes a lot to theology. Religion clearly goes way back. We don't know exactly how far back it is, tens of thousands of years, but I also think that a lot of the stuff we're discussing, these sort of moral sentiments, like tit-for-tat or reciprocity, for example, the evolution of the sense of reciprocity, that you see in elephants. That precedes... That goes way back. It's a pre-religious sensibility that we humans have, or...

1:42:15 SC: Yeah, but they have morality, not meta-ethics... [chuckle] They don't worry about a foundational basis for their actions, that's uniquely human, right?

1:42:24 NC: I would agree with that.

1:42:26 SC: Okay, so when you write a book like this, why do you do it? Who's your audience? Are you reaching for the general public? Is this something that you think of as part of your wider mission as an intellectual, or is this just part of your scholarly CV?

1:42:44 NC: God, that's a good question. I would say that there are many different reasons. One is it's both painful and joyful to write a book.

1:42:53 SC: Oh my goodness.

1:42:54 NC: Yeah.

[chuckle]

1:42:54 NC: Yeah. It exercises a certain part of your mind, it's a kind of discipline. I love the learning that goes into it. You never learn anything as well as when you have to teach it, and you really have to drill down and drill down. I love all the meandering paths, and you stumble on stuff as you look at one paper's references, then another paper's references, then another paper's. Then you find this incredible classic, some forgotten scholar in 1890, who saw things the right way. Nobody understood it, you know. It's incredible how smart those guys were, and we think we're discovering everything. So all of that is very joyful, but it's painful. It's difficult to distill everything down to kill your darlings, to articulate it, to finish the project, to allocate the time, all of that stuff. So first is just personal satisfaction. I like it. This is my third book. My third unedited book. I've also done some edited some clinical textbooks on hospice medicine. So the first one.

1:43:58 NC: Second point, I think the audience is my peers. You're trying to make an argument, you're trying to say to your colleagues, you're trying to defend and advance a certain perspective on the world. You're trying to say, "Look, I think these ideas help us organize our thinking and do you agree with me? Please agree with me that this is a healthy way to think about things." And then I think as you alluded to, I think there's also the broader public. And here I think that as academics we have a... I would even go so far as to say an obligation to serve the needs... No, to advance the public understanding of science. I think universities and academics are the institutions in our society that are supposed to preserve, produce and disseminate knowledge. We're supposed to preserve Sanskrit and preserve shell anatomy and preserve every obscure branch of human knowledge.

1:44:55 NC: And we're supposed to disseminate it. We're supposed to discover new stuff, that's clearly a hugely important mission and we're supposed to do that without reference to its utility, because we... I think it's a mark of our civilization that we do this. We give money to institutions and people that just supposed to sit around and think up stuff. I think it's miraculous and I think it's a source of our wealth. I could make an argument it's a source of our wealth and power. And has been. Ancient kings did the same thing they... Galileo let's not forget was in the pay of the Medici's and you know all of these... You know, Archimedes worked for the king of Syracuse and so forth.

1:45:35 NC: So we're supposed to do that, but we're also supposed to disseminate the knowledge and we're not supposed to just disseminate it to ourselves, we're supposed to do disseminate it back to our pay masters which are the society at large. And so I think in that regard, I think the engagement with the public understanding of science and the effort to increase the way in which people see the utility of science and of knowledge, I think is important. So that's another reason to write books.

1:46:04 SC: Yeah, so I think very quickly before I probably...

1:46:06 NC: Well, you think about those. You do same thing of course.

1:46:08 SC: I do. I was gonna say two things, one, just that this wonderful fact that you are allowed to dive into the literature and the research and the other fields and to be inter-disciplinary and to talk to people outside. This is a wonderful feature of writing books. And I had it when I was writing The Big Picture. My podcast audience here knows this, but this was a major motivation for me starting Mindscape podcast, because when I stopped writing that book my license to knock on people's doors went away. Well, how do I get to talk to Nobel prize winning biologists now? But now I can do it 'cause I have a podcast. So here we are. You might want to start a podcast, if you wanna do this. And the other one was...

1:46:51 NC: I could never catch up with you though Shawn, I think you're doing it. So I'll just... I'll just work it... You're doing it so well. You and Niles.

1:46:57 SC: It's a big ecosystem out there. And the other one is... Yeah, I think that it's very interesting to think about the audience and how we write books, because especially in physics there is a well-established tradition of outreach popularization books. Where you're basically trying to under... To explain something that is perfectly well understood, general relativity or particle physics or whatever. And sort of secretly, it shouldn't be secret, I should be louder about it, but my books aren't mostly that. My books are actually like you said trying to make an argument. And you can disagree with them for the most part. It's not simply saying here is stuff, here is why space-time is curved.

1:47:35 NC: Let me explain to you at large.

1:47:37 SC: Yeah, I'm trying to say, "Let's go beyond a little bit." And partly I do it in the trade book format to reach a broader audience but partly because it is kind of a bigger picture, more interdisciplinary thing that would be less appropriate for a professional journal article.

1:47:54 NC: Yes, I think that's right. And I also think there's a way in which... I mean this is a bit of the craft of being a professor at our stage of life I would say that I like to take intellectual risks both in my own laboratory. I like to say my students will say I'll go to them. I'll say, " This is crazy, but it's gotta be true." And...

1:48:18 SC: Oh, yeah [chuckle]

1:48:19 NC: And 50%... More than 50% of the time I'm right. They take bets on whether I'm right or not, and I have a pretty good nose at this point for stuff that's crazy but it's gotta be true. And it very hard to publish that stuff in peer review journals as you know. And until you get all the right evidence this the path to proving something is unusual... What is it, extraordinary claims require extraordinary evidence. So, but with the books the thing you can do is that they're not peer reviewed.

1:48:47 NC: So one of the things that I find very, very welcoming about writing a book for... Is that while I stand behind everything in the book and I have thought deeply about it and researched it at length and 20% of stuff are experiments I've done in my own personal laboratory. I know it down all the way to the bottom level what's going on there, nevertheless you have more breathing room. You don't have those peer reviewers that are breathing over your neck, and saying, "Well, can you say that or I disagree with that." Because I disagree... R3 says, "Because I disagree with that, cut it out of the paper." You're like, "No no, I wanna see this thing." So just...

1:49:21 SC: Yeah, and it gets worse the more interesting your work gets in some sense. You know I feel myself like 10 or 20 years ago, I was doing pretty darn mainstream cosmology and gravitation theory. And I never even contemplated the possibility that a paper that I wrote would get rejected. It's just like you do the solid work and it'll get accepted. And these days I'm doing infinitely more interesting work but it is more speculative, more interdisciplinary. And now I'm always worried that I'll get... Half the time it sails through fine and other half the referees decided to be obstreperous. But sadly, and it really, it hurts me to admit this, but my opinion of academia has gone down in the last decade because as it affects me personally, the fact that academia is so conservative and traditionalist and hide-bound...

1:50:15 SC: Is just much more obvious, and there's a reason for that. It's just like the evolution of different human capacities, there's sort of selection pressures that push it in that way, but it's too bad that there's not more room in there for encouraging just a little bit of off the beaten path kind of stuff. And the reason why I say I'm reluctant to say it is, 'cause it will give solace to all sorts of complete crackpots who'd say, "Yes, my theory about how the universe is made of pipe cleaners is absolutely being rejected by the establishment, but so be it."

1:50:48 NC: Well, it's more than that, first of all, I would agree 100% with everything you just said in the last two minutes. And I've had a different career than yours in different fields, and I don't know if we've ever overlapped in universities, but mostly different universities. And it's the same thing, and it's really... Sometimes describe my laboratory as the Island of Lost Toys.

[chuckle]

1:51:09 NC: I've gotten to the point where I can provide some cover and protection for my students, but I worry because I have tenure, and I have job security, and I have reached a certain stage where I can take these risks, but I don't know, I want to let them take their risk, I wanna encourage them to, and we all know the famous scientists that swam against the tide, made those major discoveries, but the truth of the matter is, for every one of those we know, they're 999, who either were wrong, or they were right, but they spend their whole life beating their head against the wall and we're never recognized in their lifetime. They were penniless, and had no jobs and so forth, even though they were right. So we only hear about those outliers who were right and successful, and it's very difficult to organize a career or to mentor young people in this regard. So I typically give the advice of, "Belt and suspenders." I say, develop technical expertise, develop detailed knowledge about a narrow, very conventional kind of thing. And even though you are young, still have these crazy ideas that you pursue in parallel and just work harder. Do two careers until you get to the point where you can really give yourself liberty to go off in crazy tangents.

1:52:18 NC: There's all these guys at MIT, these full professors that... You go to talk to them, and you're like, "Well yeah, this is the stuff I'm publishing and sell, but let me show you the really cool stuff."

[chuckle]

1:52:26 NC: That's over here in the back room, and their eyes light up. I think we're talking now about different things, we're talking about just a craft of mentoring young people, and we're also talking about having a good life in science. And for me, I would rather take risks that I might... Here, let me just tell you this, and I'm sure you feel the same way. Once you've tasted at the well of scientific discovery, There's no, no other feeling like it.

1:53:05 SC: Nothing like it, yeah.

1:53:06 NC: Nothing like it. If you're the first to see something, anything, can be the tiniest damn thing, and you have that feel, "Oh my God, look at this thing that I saw."

[laughter]

1:53:16 NC: And nobody has thought of it before, seen it before. It's like a drug, right? You just want it again, and you will invest years for that again. And so that's... I try now that I'm at the stage where I'm at, and to allow myself that pursuit. And a lot of my grants get rejected, a lot of my papers get rejected, and I think more than yours, judging from your hit rate you were describing. But I would rather... At this stage of my life, that's the game I would rather play.

1:53:50 SC: Well, it seems like you've been doing it very successfully, and at the very least, we have our books and podcasts to fall back on.

1:53:55 NC: Yes, Thank you.

1:53:55 SC: So, it's a true, a real intellectual pleasure to be discussing these ideas.

1:54:01 NC: Sean, thank you so much.

1:54:02 SC: Alright, Nicholas Christakis, thanks so much for being on the podcast.

1:54:05 NC: Thank you.

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