The Past is Never Dead

How does the culture in which you live shape the life that you lead? We all know that culture affects the languages we speak and the foods we eat. But anthropologist Joseph Henrich says the impact of culture goes even further, reaching into our bodies and our minds. He takes us on a journey through time to show how human cultures create a "collective brain," and how that shared knowledge profoundly shapes who we are and how we live.

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

• 0:00Shankar Vedantam?

  Hey there, Shankar here with some exciting news. Our live perceptions tour is returning this summer in partnership with public radio stations around the country. This time, we're heading to Northampton, Massachusetts, Burlington, Vermont, Boulder, Colorado, Grand Rapids, Michigan, Blacksburg, Virginia, San Luis Obispo, California, and Oklahoma City, Oklahoma. More information is at hiddenbrain.org/tour. I hope to see you at one of our upcoming stops. Okay, here's today's show. This is Hidden Brain. I'm Shankar Vedantam. Think about a time you flipped through an old family album.

• 0:44Shankar Vedantam?

  Maybe you paused on a photo of your grandparents as young adults. Their clothes look outdated, their expressions too formal. Perhaps you imagined what it was like to live in that time and found it impossible. Or think of a film set in medieval times. You may have thought, wow, these people lived in a completely different universe. I have so little in common with them. It's easy to believe the past is sealed off from us, that those lives, those cultures, those ways of thinking have vanished from the world. But is that true?

• 1:29Shankar Vedantam?

  In ways we don't even notice, the choices, beliefs, and habits of people who lived long before us continue to shape how we see the world today. They influence what we value, the kinds of societies we live in, even how we relate to one another. This week on Hidden Brain, and in a companion story on Hidden Brain Plus, how culture and history shape the way we think.

• 2:08Shankar Vedantam?

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• 2:52Shankar Vedantam?

  That's why Mazda has been named Consumer Reports' safest new car brand. To learn more, visit MazdaUSA.com. Consumer Reports does not endorse products or services. Support for Hidden Brain comes from Southern New Hampshire University. The brain isn't fixed, it's flexible. That means we're always capable of transformation. A master's degree from SNHU can help you build the skills to become whoever you want: a leader, career changer, dream chaser. With no set class times and low online tuition, SNHU makes grad school possible because it's never too late to learn something new. Get started at SNHU.edu/brain.

• 3:37Shankar Vedantam?

  When you woke up this morning, you turned off your alarm and brushed your teeth. You had a bite to eat, said goodbye to your spouse, and commuted to work. You clocked in for the day. All of this seems so routine, so commonplace, that we don't stop to think about it. We don't realize how the patterns of our lives are shaped by the long ago and the far away. As the novelist William Faulkner once said, "The past is never dead. It's not even past." At Harvard University, Joseph Hendrick has studied how people who lived in previous centuries continue to shape our lives today. Joe Hendrick, welcome to Hidden Brain.

• 4:15Speaker 01

  It's great to be with you.

• 4:18Shankar Vedantam?

  Joe, I find myself checking the time constantly. I'm always running from one thing to the other. I sometimes feel like I live my life according to the dictates of my calendar. You've studied what life was like for people before mechanical clocks were invented. Paint me a picture of that world.

• 4:36Speaker 01

  Yeah, that was a world governed by sunrise and sunset, where there were still 12 hours in a day, but the length of those hours varied. There were seasonal rhythms that helped people organize farming. And it was just a very different world than the constant interest in time and saving time and getting more time and thinking of time as money.

• 5:05Shankar Vedantam?

  I'm imagining that, given that people lived in different time zones and in different latitudes, people really started and ended their days at different times in different places of the world.

• 5:18Speaker 01

  Yeah, I mean, everything was organized around sunrise. And of course, that varies if you're not along the equator. That changes throughout the year. There were no electric lights. Candles were expensive, so people had to adapt to the availability of light. And of course, everybody was farmers, or almost everyone. So that meant that the seasons really mattered a lot. The weather mattered a lot, and you had to organize your work around those cycles.

• 5:47Shankar Vedantam?

  I understand the first mechanical clocks appeared around the 13th century?

• 5:52Speaker 01

  That's right. They began spreading in northern Italy, so places like Milan and Parma. But then they were very popular, so they rapidly began spreading amongst urbanizing parts of Europe, so getting to Paris and London. And initially, there wasn't a clock per se. It was just tied to bells. So the cities and towns, everybody was within earshot of the ringing bells. And so it would ring the beginning of the day and breakfast and lunch and whatnot. So the entire city would move in clockwork with the ringing bells. And then eventually, you get a clock face, and things go from there.

• 6:31Shankar Vedantam?

  I understand that various towns began to compete with one another to to install beautiful and magnificent clocks.

• 6:39Speaker 01

  That's right. So clocks were a sign of town wealth and prestige. Famous artisans would construct the clocks and clockmakers became an important occupation. And they wanted clocks that were as good as the clock in Vienna or the clock in Paris, you know, competing.

• 6:58Shankar Vedantam?

  I'm wondering how this invention changed the way people lived. So now, all of a sudden, you know, you're not just going according to the the rhythms and cycles of the sun, you actually have something that tells you it's 11 o'clock in the morning, or 10 o'clock in the morning, or 2 o'clock in the afternoon. How did that change day to day life?

• 7:15Speaker 01

  Yeah, it really changed the economic and political system. So legislatures would begin meeting at certain times of the day, and there were fines if you were late. Contracts began to have exact dates when you had to have things due. Witnesses were told to report at court at a certain hour. So it really just reorganized the society. Not only that, it was seen as a good and orderly life to live by the clock and have regular prayers and regular religious services and show up to work on time. So punctuality began to be tied to probity, and all this was woven in with religion. So of course, monks had long been timing their prayers using candles and hour glasses, and then they began to incorporate the clocks and the bells.

• 8:04Shankar Vedantam?

  I understand that there's fascinating research looking at towns and cities that installed clocks before other towns and cities, and that this had a profound effect on productivity and wealth?

• 8:18Speaker 01

  Yeah, so this is fascinating research coming out of economics. And if you look at the few centuries after these towns throughout Europe adopted clock, you actually see an uptick in economic growth in the centuries after the clock arrives. So it's not an instantaneous effect, because people actually have to adapt their thinking. And it takes a long time to get used to thinking in this time-thrift way in which we all, you know, we're all very tied to the clock. We've internalized it. But that's not something that automatically happens.

• 8:52Shankar Vedantam?

  And do you think this increase in productivity, this increase in wealth was really a result of people harmonizing their schedules? In other words, I can show up somewhere and I know that someone's going to meet me at a certain time and place. I don't have to wait two hours for them to show up because, in fact, they're following some different cycle.

• 9:07Speaker 01

  Yeah, so it increased people's ability to coordinate, but it also began to affect other things like payment schedules. So, once you have clocks, you can pay people by the hour. And then, at the same time, you get the spreading of piece rates. So, people begin manufacturing, markets are spreading across these towns. And then, if you pay a piece rate, so per horseshoe that you're making, then people begin to think about, and if they have a clock, they can figure out, well, how many horseshoes can I make in an hour? Maybe I can make five. Well, what if I can make six? Then, you begin to think about the world like that.

• 9:39Shankar Vedantam?

  So, you're an anthropologist, Joe. I understand that you were once working in Fiji, and you noticed that the way that you think of time was very different from your collaborators in Fiji.

• 9:49Speaker 01

  Yeah, so I was starting a project, and I was hiring some students from the University of the South Pacific, excellent research assistants, were assisting me in this village, and we were doing interviews and observations on daily life. We were doing some behavioral experiments, all kinds of different things. So, I was kind of running the project in the style I was accustomed to, which meant we had morning meetings and certain appointments, and I would give people a certain amount of time to finish things. And initially, I wasn't having much luck. Although the research assistants were excellent in many ways, they didn't seem to be very tied into the clock the way I was. And so, then I bought everyone watches. So, I figured, you know, maybe I can solve this with technology. And of course, I was paying everyone.

• 10:33Speaker 01

  This still didn't seem to change anything at all. Everybody was wearing the watches. And then, on one funny occasion, I was working closely, we were looking at this laptop with our research assistant, and I happened to look down at his watch, and it said something like 11:20. And it turned out, his watch was about 25 minutes off. And so, I think it had been that way for weeks or possibly longer.

• 10:55Shankar Vedantam?

  So, what's striking, of course, is that people like me certainly sort of, you know, bemoan the fact that other people are not punctual or they don't show up. But in some ways, you know, not paying attention to the clock is actually a more natural state of things, if you will.

• 11:09Speaker 01

  Yeah, that's right. In lots of places, it's considered bad to be paying too much attention to the time. When you meet with somebody, you shouldn't be rushing off to your next thing. You should be taking time to connect with them, see how their family is, swap stories, you know, sort of reconnect, focusing on the social. I mean, you know, in some societies, the clock is seen as the kind of the devil, right? Because it's what drives people away from really forming these tight social bonds and nurturing the social bonds through time. Psychologists, Arunorn and Zion and colleagues have actually gone around the world and tried to measure this in different cities. And they found that things like how long it takes to get to a stamp, the rate at which the guy behind the counter is moving, actually varies from city to city.

• 11:54Speaker 01

  And they actually correlated with the measures of individualism for those cities.

• 11:58Shankar Vedantam?

  Meaning that places with higher individualism are more punctual and vice versa?

• 12:03Speaker 01

  That's right. And the person behind the counter is actually moving faster and the clocks in public places are more accurate. So that you can measure the accuracy of the clocks in public places.

• 12:15Shankar Vedantam?

  What's fascinating here is that these conceptions of time have seeped into our lives to the point that we're not thinking about them anymore. It's hard to imagine a time when people didn't keep track of time.

• 12:28Speaker 01

  Yeah, and it restructures our life. One of the amazing things, and you can find this in the work of Ben Franklin, is that he emphasizes the equation between time and money, which is not something you find elsewhere. And of course, this metaphor has now spread globally. And this is one of the things that dominates our life. You know, we're always wasting time, saving time, losing time. You know, there's time is this currency that we're trying to get more of.

• 12:57Shankar Vedantam?

  We like to think our choices, our thoughts and our habits are entirely our own. But in reality, our individual choices are often echoes of centuries of cultural evolution.

• 13:10Shankar Vedantam?

  When we come back, the role of history in shaping our behavior, thoughts and feelings. You're listening to Hidden Brain. I'm Shankar Vedantam.

• 13:31Shankar Vedantam?

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• 14:10Shankar Vedantam?

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• 14:28Shankar Vedantam?

  This is Hidden Brain. I'm Shankar Vedantam. We think that the lives we lead are shaped by the choices we make. But many of the routines we follow were shaped by centuries of history and cultural evolution. Anthropologist Joseph Hendrick looks at the way history and cultural evolution shape what we think, how we see the world, and the decisions we make. He's found that even things we see today as moral and right were often inventions by ancient actors who had specific goals and political aims in mind.

• 15:03Shankar Vedantam?

  I want to talk about the relationships that undergirded most of our lives today, Joe. Marriage, the nuclear family, rules of inheritance. Transport me back to pre-Christian Europe. What were familiar relationships like for most people back then?

• 15:20Speaker 01

  Well, at that point in European history, the kinship systems, the families, the clans, look like large extended families. In Europe, it's patrilineal, and lots of other places in the world, it's matrilineal. People inherit through the family by custom. Their societies are organized by clans. The economic system, the political system, is all very tied into these kin relationships. So, for example, many kin groups have corporate responsibility, which means if someone else in your clan, or including especially your brother, commits a crime, then you can be held responsible. So you're considered synonymous with your close kin. If someone within your kin group does something shameful, then it actually brings shame on you.

• 16:05Speaker 01

  So shame is contagious through these kin networks. Marriages are often arranged. People play bride price or dowry. This forms a bond between groups. And people are also tending to marry endogamously. So with close kin, like cousins, things like that, or other relatives.

• 16:25Shankar Vedantam?

  And kin also provided a kind of social security. They provided a kind of protection, insurance. I mean, so you had these large groups in some ways, and they were all responsible for each other, looking out for each other.

• 16:40Speaker 01

  That's right. So they're not only the core of the economic system, but they provided a social safety net. So if your husband dies, a typical thing would be you would marry his brother. And then you would maintain the bond. And as a woman, you would be taken care of, and your children would still be part of that kin group. So there was all these social norms to kind of take care of things. If both parents were killed, then the children would automatically go to other members of the family, where they'd be raised and taken care of and whatnot.

• 17:13Shankar Vedantam?

  So at one point, the Roman Catholic Church begins to spread across Europe. Pope Gregory dispatches a mission with specific instructions regarding marriage in particular?

• 17:23Speaker 01

  Yeah, this is happening all throughout Europe as missionaries are moving from the Roman Empire and from Rome out to the Celtic tribes and other Anglo-Saxon tribes, other Germanic tribes, to try to spread Christianity to these places. And when this monk named Augustine arrives in Kent, he begins to convert the king and his wife, who was already Christian, she married, and she was a Frankish princess. So Augustine queried the pope to find out what kinds of things he should be conveying as he faces these challenges from the local people in Kent. And so one question he asked the pope is, how distant must a relative be for a Christian marriage to be permissible? So can I marry second cousins? Can I marry third cousins?

• 18:08Speaker 01

  Another question was, can a man marry his stepmother or his brother's wife? And then can two brothers marry two sisters? And can a man receive communion after a sex dream?

• 18:23Shankar Vedantam?

  How did the pope respond to these questions?

• 18:25Speaker 01

  Yeah, so the pope, to the first question, he said, definitely can't marry first cousins. During this period in history, the Church was definitely banning first cousins. They would go on to ban all the way out to six cousins, but at this point, you could marry your second cousins. And you cannot marry your stepmother. So it's not about genetic relatedness, it's about these family relationships that are created. And certainly not your brother's wife. So that would be a kind of leverate marriage. And the Church banned that pretty early on in the history of the Catholic Church. Two brothers can marry two sisters, so that was okay.

• 19:03Shankar Vedantam?

  So another people's commission arrives in England a couple of centuries later. They're checking in on the progress of Christianizing the Anglo-Saxons. What does it find?

• 19:12Speaker 01

  Yes, and in general, there's a lot of progress on people officially accepting Christianity. Lots of people have been baptized, but there's still problems around what they describe as incest, by which they mean cousin marriage of various kinds, and also polygyny. So elite men are taking one primary wife, but they're also marrying other women as secondary wives and concubines.

• 19:35Shankar Vedantam?

  And so I'm imagining the Church might not look kindly on these developments.

• 19:40Speaker 01

  Yeah, so the question was, is how do we put an end to this? You know, we like the idea that the Church is spreading and these people are becoming Christians, but these forms of family weren't acceptable. So one of the things that the Christians really pushed, the Church leadership really pushed, was the notion of illegitimate children. So the lever they used was that unless you were married in an official Christian church, then you're an illegitimate child, which meant secondary wives in this system, like in many places around the world, their children still had some inheritance rights. They were still recognized by the community, but the Church tries to put an end to that to prevent not only inheritance of wealth, but succession. And this is going to affect the royalty a lot because it means the Church controls

• 20:25Speaker 01

  who gets to be the next leader when you have descent of power down the bloodline.

• 20:37Shankar Vedantam?

  One of the other things that the Church required was to ask newly married couples to set up independent households. Talk about this idea, Joe.

• 20:47Speaker 01

  Yeah, that's right. So that's called neolocal residence, and it's very rare in a global and historical perspective. So when young couples will marry, typically they would live either with the groom's family or the bride's family, depending on whether they're patrilocal or matrilocal. So that's the anthropological terminology. But what we find in Europe during this period is the Church are encouraging them to marry later and set up an independent residence so that they're independent from either side of the family. And so you have a new couple making their own decisions, independent of the family.

• 21:21Shankar Vedantam?

  Now, I imagine that there must have been some people who looked at these new rules and said, you know, the hell with these rules. I'm just going to go my own way and do my own thing. Were there punishments for people who violated these rules?

• 21:32Speaker 01

  Yeah, there could be quite severe punishments. So the church can always excommunicate you. And then there's something even more severe called an anathema. And excommunication might, in the modern context, not sound very severe. But it meant you couldn't enter into contracts with other Christians. You were ostracized. Those who might associate with an excommunicated individual got some of this spiritual taint on them, and it could affect their relationships. And in some cases, the church's protection of you was withdrawn. So if someone killed you or injured you, it wasn't considered a crime. So being excommunicated had real heft.

• 22:19Shankar Vedantam?

  Did all this change the way people behaved, Joe?

• 22:23Speaker 01

  It took a long time, but it eventually breaks European families in different parts of Europe to differing degrees down into monogamous nuclear families. So you went from large clans and kindreds down to, you know, the husband, wife, and the children. And that was the basic family unit.

• 22:40Shankar Vedantam?

  One of the things that happened as a byproduct of this is that people started to think in terms of individual rights and personal responsibility rather than always prioritizing family loyalty and kin. Talk about this. I find this fascinating, Joe.

• 22:56Speaker 01

  Yeah, because what the church did by having these prohibitions and prescriptions about marriage in the family is you no longer had a big clan or this large extended family that you could rely on. You couldn't build alliances by marriage very easily. So people began to set up voluntary associations where people would join. These were often Christian-based. You'd have to take an oath. And in order to get those organizations interested in you, you'd have to have certain attributes and accomplishments and things you brought to the table. So rather than having a large number of relationships that you inherited by birth and had via all these various kin ties, you had more of these optional relationships where you had, it was kind of a, more of a marketplace for relationships. So this affected finding mates.

• 23:40Speaker 01

  So rather than arranged marriages, you had to find your own mates, friends, business partners, all these sorts of things. And it led to the proliferation of these voluntary associations.

• 23:49Shankar Vedantam?

  You talked earlier about how kin groups would look after one another. So if someone was in trouble, or if someone lost a spouse, or if children lost their parents, the kin, the larger kin, would look after the person who needed help. What happened to those systems as things became more individualized?

• 24:09Speaker 01

  Yeah, a few different things. So the one thing the Church did, it had to step forward almost immediately on this, is to take care of orphans and widows. Because normally, they were sort of just slotted right into the kinship system, and there were norms that took care of them. What the Church did meant that there was really no one to care for orphans and widows. So the Church began to take them in, and they became core members of the Church in that sense. These voluntary associations that people would join were also mutual self-help groups. So you would all mutually agree to help each other out if you were injured, or had a period of unemployment, or in your old age and whatnot. And then eventually, after the beginning of Protestantism, when the Church is not

• 24:53Speaker 01

  doing this in places like England, after Henry VIII gets rid of all the Catholic institutions, Queen Elizabeth initiates the Poor Laws of 1600. And this is the beginning to lay an official, secular, social safety net under people who might need it.

• 25:11Shankar Vedantam?

  So in some ways, the picture that you're painting, of course, shows us how many of the institutions that we're familiar with today actually had a point of origin, that in fact, they arose as a result of choices made by specific actors and specific circumstances, and many of them had specific political and social goals.

• 25:30Speaker 01

  That's right. But a lot of it is also unintended consequences. So the Church, of course, was doing this because they believed that this is how God wanted it. And so when plagues would hit, the Church would explain the plague as a consequence of there being too much incest, by which they meant too much cousin marriage. And the breakdown of these families into monogamous nuclear families inadvertently led to the rise of these voluntary associations. Which gave us the many charter towns of Europe, universities, new kinds of monasteries, and these mutual self-help associations, which eventually become occupational guilds. So many of those things become some of the core institutions of Western society.

• 26:25Shankar Vedantam?

  Talk about the family, the kind of family that we are used to seeing around these days, the nuclear family, you know, husband, wife, kids, living by themselves. Talk about how that's actually quite unusual in the history of the species on the planet.

• 26:40Speaker 01

  Yeah, so when you look at the anthropological data on this, so anthropologists have put together something called the ethnographic atlas, which is over 1,200 diverse societies that have been studied in ethnographic detail. You find that most, 85% of societies, allow elite and high-status men to marry additional wives. You find cousin marriage in most societies is permitted. Neolocal residence is very rare, although common in the West, as we discussed, and just many other kinship practices like leverate marriage, which you don't find in the West, are common around the world. So it's as if these norms evolved to build these dense networks of kin, to organize production and consumption and distribution.

• 27:23Speaker 01

  And by preventing this from happening in parts of Western Europe, the Church actually opened the door to new kinds of institutions and new ways of thinking about the world.

• 27:36Shankar Vedantam?

  Hmm. You coined a term for the kind of modern psychology that animates Western-educated, industrialized, rich, and democratic societies. Tell me about this term, Joe.

• 27:49Speaker 01

  Yeah, so this began in about 2005, when I arrived at the University of British Columbia. And there I was moving out of anthropology into psychology, and I encountered two colleagues, Steve Heine and Aron Noren Zion. And we would go to lunch together and we were each talking about our research and we were studying, all studying cultural differences. And what we had each independently found is that not only was there interest in cultural variation around the world, but that the populations most studied by psychologists and economists were psychologically peculiar when placed in a global and historical perspective. So, we began to think about and try to put together a case trying to convince psychologists

• 28:31Speaker 01

  and economists that they needed to think more broadly about psychological variation and just not generalize to all of humans based on one common culture that they most commonly studied. So, we coined this acronym, or I guess it's a B acronym, WEIRD. It stands for Western, Educated, Industrialized, Rich, and Democratic.

• 28:50Shankar Vedantam?

  You noticed differences between these so-called weird societies and other types of cultures while you were working with a tribe in the Peruvian Amazon. Tell me about this work and what you found.

• 29:01Speaker 01

  Yeah, so this was my very first anthropological fieldwork and I went to the Peruvian Amazon. I flew in on missionary planes and landed on the river and went into the village and then I traveled around, in a dugout canoe, around to the different villages. And at this point in my career, this is kind of the mid 1990s now, I'm studying cooperation. And one of the ideas that we were thinking about was the possibility that the willingness of other people to punish poor behavior, non-cooperative behavior, unfair behavior, might be part of the reason why humans are able to cooperate so much compared to other species. And so, we were thinking about that. And then I heard about this experiment called the ultimatum game.

• 29:45Speaker 01

  And the ultimatum game is a simple bargaining game from economics in which two players are allotted a sum of money and the first player can offer a portion of this money to the second player. The second player can either accept or reject. If they accept, both players get the amounts that were allocated, or if they reject, then both players get zero. So, for example, if the first player offers $10 out of the 100 to the second player and the second player accepts, they get 10 and the first player gets 90. If they reject, both players get zero. So when this had been done by economists in places like the US and Zurich and elsewhere, they had found that most people offer 50/50 and that low offers are frequently rejected.

• 30:29Speaker 01

  That sort of fit my intuitions. So I thought that I could perform this experiment among the Machaganga and they would show similar results. It seemed intuitive and that then this would be an interesting piece of the puzzle in trying to explain human cooperation. But what I found was that they didn't feel inclined to reject at all and people gave pretty low offers. So on average, people gave only 25% of the stake instead of 50% and lots of people gave 15%. So this led to a big project and we did this experiment in many different places and we found a great deal of global variation.

• 31:05Shankar Vedantam?

  What do you think explains this? What's happening in the minds of people in Peru that is different from Los Angeles?

• 31:12Speaker 01

  Well, I think it relates to a larger story that you and I discussed with the spread of the clocks. It has to do with market integration. And so what we found across these communities is that the more market-integrated communities seem to have norms about fair dealing with anonymous others, with impersonal people you would just meet and not know their name or not know anything about their families. So more market-integrated societies have norms that say you should just generally be fair-minded with people who you don't know and won't see again. Whereas the Machaganga lifestyle is small-scale farming. They live scattered throughout the tropical forests of Peru, north of Cusco where Machu Picchu

• 31:55Speaker 01

  is. And, you know, they're just not a lot of trade and exchange, so they don't have these market norms. And so to them, when I would interview them after, they would be like, yeah, why would anyone reject free money in this case? Which is pretty close to the rational thing one might expect based on game theory.

• 32:12Shankar Vedantam?

  Right. The differences between the so-called weird cultures and other cultures also show up in different psychological tests. Some research has been conducted looking at eye-tracking movements between Americans and East Asians. Tell me about this work.

• 32:30Speaker 01

  Yeah, so this is very interesting because it's perceptual. So psychologists have shown there's this tremendous variation in analytic versus holistic thinking. And one of the hallmarks that they found in terms of attention is what people pay attention to when they look at a scene, or a picture, or a video. And Americans, more analytically oriented societies, will tend to focus on the central object. So in this case, imagine it's a scene, an underwater scene with fish swimming around. The Americans tend to focus on the central fish, and they watch what the central fish does. They don't tend to notice very much stuff in the background. The folks from East Asia would remember a lot more about what was going in the background,

• 33:12Speaker 01

  and their eyes would cover more of the scene, and just not kind of glue to the central actor.

• 33:24Shankar Vedantam?

  Do you think this is, again, evidence of the propensity of weird societies to focus on individualism and individual objects?

• 33:33Speaker 01

  Yeah, so this is, this seems to be part of a larger package. You know, in an individualistic society, people tend to focus on themselves and their own attributes, and they think about others dispositionally. So what are the attributes of another person, honest or dishonest, without thinking of all the contextual variation. Whereas if you're from a more holistic society, a more collectivistic society, you're thinking about the relationships between individuals. People aren't either honest or dishonest. They're honest in some circumstances with some kinds of people, and not so honest in other kinds of circumstances. So there's this, this interesting, different ways of thinking about the world.

• 34:14Shankar Vedantam?

  One of the things that I find fascinating about all of this is that it highlights just how much we can take culture for granted. So for example, we might live in mostly monogamous societies, and so we assume that humans must be wired for monogamy. That in fact might not be the case.

• 34:31Speaker 01

  Yeah, it's amazing how strong the intuition is, is that however it is where I live is how it is to be human. So yeah, one of the things I've been most interested over my career is trying to figure out what is actually pan-human, and what is just the particular societies that we grow up in.

• 34:51Shankar Vedantam?

  The invention of clerks and religious rules for marriage all profoundly influenced the way modern people think and behave. More about how culture shapes our minds when we come back. You're listening to Hidden Brain. I'm Shankar Vedantam.

• 35:18Shankar Vedantam?

  This is Hidden Brain. I'm Shankar Vedantam. Have you ever given thought to how your daily life might be shaped by events from the distant past or by traditions thousands of miles away? If you have a personal example you'd be willing to share with the Hidden Brain audience about how the past shapes your behavior today, please find a very quiet room and record a voice memo on your phone. Two or three minutes is plenty. Email the file to us at [email protected]. Use the subject line "culture." Again, that's [email protected].

• 35:55Shankar Vedantam?

  Anthropologist Joseph Hendrick is the author of the books "The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter", and "The Weirdest People in the World: How the West Became Psychologically Peculiar and Particularly Prosperous."

• 36:14Shankar Vedantam?

  Joe, in June 1845, two ships set sail from Britain in search of the fabled Northwest Passage. Tell me about this mission and the man who was leading it.

• 36:26Speaker 01

  Yeah, so this mission was led by Sir John Franklin, and it was an effort to find the fabled Northwest Passage with economic goals of energizing trade and connecting Europe and East Asia, and also doing some mapping of that area, understanding the magnetic field. And it was a fascinating expedition because it was kind of the Apollo mission of the 19th century. This was a super well outfitted ship. It had icebreaker technology. It had retractable screw propellers. It was insulated with cork. There were desalinators on board. And it had a new technology, canned food, which was meant to allow the crews to live

• 37:08Speaker 01

  for over a year trapped in the ice in the north. So they were ready to engage in this exploration. And they were led by this experienced guy, John Franklin. And so they headed out and the very beginning of the trip went fine. They were exploring the islands north of Canada. They wintered near an island called Devon Island. The ice came in around the ship as expected. I guess they cracked open the canned food and waited the winter out until the ice retracted. And then they kept exploring. But the next year, they were near King William Island and they were exploring around there. And the ice came in again and froze them in. That was all expected.

• 37:53Speaker 01

  But the next summer, the ice didn't seem to retract. And so they were going to have to winter again. And that seemed like that was going to be a problem. Their leader Franklin promptly died. So the men were trapped in the ice and they were faced with a challenge of living off the land. Because they have to see if they can use their big brains and great intelligence to figure out how to do something very basic, which is surviving in the Arctic.

• 38:19Shankar Vedantam?

  What happened?

• 38:20Speaker 01

  Well, things did not go well. So the men eventually left the ship and they began trying to survive on King William's Island. They left some notes along the way, which were later found and the ships have soon been found. So we're not exactly sure what happened, although we know from tales from the Inuit bands that they encountered, that there was probably some cannibalism going on. One Inuit story has them first encountering them and beginning to exchange some meat. But then they realized the men are carrying frozen limbs. And it turned out frozen limbs of their comrades, probably. And then the men all just disappear and leave no trace of them, other than the stories and the minds of the Inuit. It led to a big rescue expedition.

• 39:03Speaker 01

  So explorers from all around the world converged on the Canadian Arctic to try to find these guys.

• 39:14Shankar Vedantam?

  Now, you pointed out something really interesting in passing here, which is that there were people who were living in this area, presumably successfully, for a long period of time. Why couldn't these men survive?

• 39:26Speaker 01

  Yeah, it's amazing. The group, the Nescalet, that was living there, Inuit, there were, for the island that Franklin was trapped on, his land of fat. Because for them, it was a rich environment that they could live on and winter on the ice and hunt seals and, in other seasons, shoot caribou with their bows. They could render seal blubber or seal fat into oil that they could use for lights, for illumination and heating. They could spear salmon during certain seasons. They made kayaks there. To them, there was just a lot of resources there. But to Franklin's men, you know, it was this barren expanse and it seemed impossible to survive there.

• 40:21Shankar Vedantam?

  I understand that some years before this expedition, another crew had found themselves stranded in the same area. Tell me about this group and what happened to them.

• 40:30Speaker 01

  Yeah, that was led by an explorer named Ross. And I think it's a great example because we can compare the explorers that did well on King William's Island with what happened to the Franklin expedition. And the main difference is in how they interacted with the Inuit. So the Ross expedition begins to open up trade relationships with the Inuit. They're able to get all kinds of clothing and food. And so they're just able to survive much more easily by taking advantage of the vast knowledge of the Inuit. They travel and explore through their new allies and new friends with the Inuit.

• 41:10Shankar Vedantam?

  You described several things that the Inuit were able to teach the visitors, including fairly complex tasks involving hunting and trapping. Can you describe some of these for me, just to show how intricate this knowledge system was?

• 41:24Speaker 01

  Yeah, I mean, the amount of insight and knowledge and skill that the Inuit have to survive in this environment is really incredible. So, one thing that the Inuit routinely did during this period was they would be able to hunt seals. And so, you had to figure out where the seals are going to be, and it had to be an area that was covered with snow, so you couldn't hear your feet. You had to create the hole in the ice, you had to know, or you would find the holes and you would see if they were actively used by seals. And then you would use a spear to wait there until you got a sense that the seal was there. And there had little feather markers that would tell you if the seal was there, and

• 42:06Speaker 01

  then you would plunge your harpoon into the hole. You needed a special bare-bones handle, because you needed some really strong materials for the end of it that you would use to drive into the seal. And then, of course, you had to know what to do with the seal once you got it out. They also made sleds, and they made use of dogs, and they made this special cold-weather clothing. So, just an immense range of cultural knowledge.

• 42:30Shankar Vedantam?

  And, of course, this is not testament to the fact that the Inuit were necessarily smarter than their visitors. They'd had more time, and they'd passed on this knowledge, presumably from generation to generation, each generation adding some new insights.

• 42:44Speaker 01

  Yeah, so that's the key thing, is that the Neskalit benefited from this accumulative cultural evolution. So, over generations, this large body of knowledge had increasingly adapted the Inuit to surviving in this environment. So, it wasn't that they were smarter, it's that they had this large body of cumulative knowledge, which Franklin's men did not have.

• 43:04Shankar Vedantam?

  So, this gets at something that researchers call the cultural intelligence hypothesis. What is this hypothesis, Joe?

• 43:13Speaker 01

  Well, this is the idea that really what our brains have evolved and why they've gotten so much bigger than our primate relatives or than our ancestors 2 million years ago is that our brains evolved to acquire, store, and organize cultural information. So it's not that our brains have evolved to individually solve problems. What we're really good at is taking advantage of all the information stored in the minds around us and the minds of others, and then we acquire that. And we can even create new things by recombining things that we acquire from different people.

• 43:49Shankar Vedantam?

  So this kind of cultural transmission of knowledge and ideas leads to an idea that you call the collective brain. What do you mean by this, Joe?

• 44:00Speaker 01

  Well, the collective brain emerges when people are learning from each other because information is flowing around from different minds. And once you have this view, the ability of a society to generate innovation or creative ideas, this process of cumulative cultural evolution that we referred to before, is going to depend on the size of the population, the social interconnectedness among individuals, because that allows the information to flow, and the cognitive diversity in those minds. So you're actually going to get more creativity and more innovation out of a population when you have a larger population that's more interconnected and more cognitively diverse. And that's the collective brain.

• 44:48Shankar Vedantam?

  And you can see this in places like Silicon Valley, for example, where lots of people are interacting with each other, lots of people are learning from each other, and things are able to progress relatively quickly because people are building very rapidly on top of what other people have built.

• 45:03Speaker 01

  That's right. And you see this all over the place. So for example, when railroads were spreading across the US, or in Sweden, or in Germany, when a town got hooked into the larger collective brain, you begin to get more creative products coming from that town. Just a simple physical link.

• 45:25Shankar Vedantam?

  This touches on something that you call gene-culture co-evolution. What does this mean?

• 45:31Speaker 01

  Well, one of the key elements of human history that is really emerging now is that a lot of the interesting aspects of our physiology, anatomy, and biology were actually driven by selection pressures created by cultural evolution. So, one of the best-studied cases of gene-culture co-evolution is the spread of fire, making a fire and cooking. And so, if you look at our anatomy and physiology, our digestive tract, and you compare it to other species, our fellow apes and stuff, we seem to have stomachs that are too small, colons that are too small, we have these tiny teeth. But these actually make sense, once you realize that we've long been a primate that cooks its food.

• 46:16Speaker 01

  Because cooking acts as a kind of predigestion, food processing more generally. And then this allowed natural selection to reduce the size of our stomachs, shrink our colons, give us these small teeth, because we do the digestion in this cultural way by taking advantage of fire and cooking. But of course, we don't innately know how to make fire or cook. So this is something that is completely culturally transmitted, but then has dramatically shaped our physiology and anatomy.

• 46:43Shankar Vedantam?

  Another example of how our genetic inheritance and cultural practices are intertwined has to do with the practice of monogamy and testosterone levels in men. Tell me about this research, Joe.

• 46:56Speaker 01

  Yeah, so, this is one of these things where the assumption that everybody was monogamous, people began to make generalizations. And one of the things that they generalized is that testosterone declines over men's lives. But then anthropologists began to study other societies and looking and comparing what happens to men's testosterone in polygynous versus monogamous societies. So the standard result from monogamous societies is that men's testosterone declines after they marry, and then it declines again after they have their first child. And this makes good sense in... Comparisons with other species because declines in testosterone are associated with fatherhood in other species. You're beginning to engage in the nest, you've stopped your

• 47:40Speaker 01

  pursuit of mates, and you're not engaging in much competition with other males at this point because you're moving into a fatherhood phase. But in polygynous societies, we don't see the decline, which fits the theory really well, but it just shows how institutions, whether you're going to have polygamy or anogamy, affects the endocrinology of human bodies. And so you need to think of cultural endocrinology. So the institutions affect the hormonal life cycle patterns.

• 48:16Shankar Vedantam?

  So we've talked about all the ways in which history influences our culture, culture that influences not just our psychology, but also our biology. That feeds back into the whole cycle and can influence history again. Talk about sort of the role that this is playing in transforming our understanding of our minds and our societies, because I think when most of us think about human psychology, you know, we tend to think of it in terms of what's happening inside the individual brain, what's happening inside this one person's head. And really, what you're painting is a picture that is far, far larger.

• 48:49Speaker 01

  Yes, that's right. So in the picture that I'm painting, our institutions, our languages and our technologies feed back and they shape our psychology. Now, of course, what we just talked about was gene, culture, co-evolution. So in the long run, they might affect our genetic evolution. But what's underappreciated is how much these things shape our psychology in the short term, because our minds have evolved through this gene, culture, co-evolutionary process to adapt developmentally as we're growing up in these different environments. So something like our cell phones, you know, are going to affect things like our memory and our attention. So they're actually changing how things are processed in our minds. One of my favorite examples of this is, you know, for most of human history, people didn't read.

• 49:31Speaker 01

  It was really not until the 16th century that large segments of the population began to read. But when you learn to read as a child, it actually reshapes the wiring in your brain so that you get thicker corpus callosum, that's the information highway that connects the right and left hemispheres. You get specialized circuitry in your left ventral hemisphere, and you get more whole brain activation even when you hear spoken language. So it doesn't just affect the reading, it actually affects how we process spoken language. So it's just a case where a cultural practice, learning to read, actually changes a bunch of things about our brains and about how we take in information.

• 50:15Shankar Vedantam?

  I'm wondering if this can also explain things like the Industrial Revolution, Joe. When you think about a sudden explosion of technological innovation, creativity, et cetera, do you think that's driven in part by this kind of cultural learning?

• 50:31Speaker 01

  Yeah, I really think that that is a core idea, and I bring that out in The Weirdest People in the World in my book. So when these monogamous nuclear families formed and these impersonal institutions became created, people were released from the bonds of their kinship. And we know from historical data that they began moving around Europe. And the nature of the institutions also changed, so monasteries became these transnational franchises. And artisans would have a journeyman phase in which they would go out to work with other masters after they finished training with this. All this led to greater movement of ideas around Europe, which led to more rapid innovation. Urbanization, of course, you know, was rising during this whole period for the same reason.

• 51:13Speaker 01

  Universities were one of the institutions, the voluntary associations that spread. And eventually Protestant gives rise to literacy. All of these things come together to just create a much larger collective brain in Europe that eventually results in the Industrial Revolution and really gives birth to the modern world.

• 51:40Shankar Vedantam?

  Culture doesn't just make us smarter. It can also make us more vulnerable to sickness and to death. In our companion episode exclusively for our subscribers to Hidden Brain Plus, we look at how cultural beliefs can produce higher rates of illness, homicide, and suicide. If you're already a subscriber, that episode is available to you right now in this podcast feed. It's titled "How Culture Can Harm You." If you're not yet a subscriber, please consider signing up. Go to support.hiddenbrain.org. If you're using an Apple device, go to apple.co/hiddenbrain. You can get a free trial in both places, and you'll instantly have access to all our subscriber-only content.

• 52:25Shankar Vedantam?

  Again, that's support.hiddenbrain.org or apple.co/hiddenbrain. Joseph Hendrick is an anthropologist at Harvard University. He's the author of "The Weirdest People in the World: How the West Became Psychologically Peculiar and Particularly Prosperous," and "The Secret of Our Success: How Culture Is Driving Human Evolution, Domesticating Our Species, and Making Us Smarter." Joseph Hendrick, thank you so much for joining me today on Hidden Brain.

• 52:56Speaker 01

  It was great to be with you.

• 53:04Shankar Vedantam?

  Have you ever given thought to how your daily life might be shaped by events in the distant past, or by traditions thousands of miles away? If you have a personal example you'd be willing to share with the Hidden Brain audience about how the past may be shaping your behavior today, or a question or comment about this episode, please find a very quiet room and record a voice memo on your phone. Two or three minutes is plenty. Email the file to us at [email protected]. Use the subject line "culture." Again, that's [email protected].

• 53:43Shankar Vedantam?

  Hidden Brain is produced by Hidden Brain Media. Our audio production team includes Annie Murphy-Powell, Kristin Wong, Laura Kurell, Ryan Katz, Autumn Barnes, Andrew Chadwick, and Nick Woodbury. Tara Boyle is our executive producer. I'm Hidden Brain's executive editor.

• 54:02Shankar Vedantam?

  I'm Shankar Vedantam. See you soon.