Hello, everybody. Welcome back to the show. My guest today is Lyman Stone. He's a demographer, researcher and a writer. It wasn't long ago that everyone was worried about the population bomb. And within a few short decades, global birth rates are now declining. What's going on? What is driving such a rapid change in the number of children people are having? And should we do anything about it? Expect to learn the best explanations for why birth rates are declining. Whether declining birth rates are downstream from declining marriage rates, what winning the lottery does to marriages for both men and women. Lymans controversial perspective on the impact of sperm count and testosterone levels on fertility and much more. You might have heard me say that I took my testosterone level from 495 to 1006 last year. And one of the supplements I used throughout that was Tongkat Ali momentous make the only NSF certified Tongkat Ali on the planet. That means theyre so rigorously tested that even olympic athletes can use it. And that is why I partnered with them, because they make the most carefully tested, highest quality supplements on the planet. Doctor Andrew Hubman is actually the scientific advisor for momentous.

So if you've ever wondered what supplements he would create or what he really uses himself, this is the answer. So if you're not performing in the gym or the bedroom the way that you would like, or you just want to improve your testosterone, naturally, Tongkat Ali is a fantastic research back place to start. There is a 30 day money back guarantee so you can buy it completely risk free. Plus they ship internationally. Right now you can get a 20% discount by going to livemomentous.com modernwisdom and using the code modernwisdom at checkout. That's livemomentous.com, modernwisdom, and modernwisdom, a checkout. I've worn whoop for over four years now, since way before they were a partner on the show. And it is the only wearable I have ever stuck with because it's the best. It's so innocuous, you don't remember that you've got it on, and yet it tracks absolutely everything 24/7 via your wrist. It tracks your heart rate, your sleep, your recovery, all of your workouts, your resting heart rate, heart rate variability, how much you're even breathing throughout the night. Puts all of this into an app and spits out very simple, easy to understand, and fantastically usable data.

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They're going down, as in every country, essentially. So, yeah. I mean, in 2007, the average woman had 2.1 kids per woman. Today it's closer to 1.6. So half a child missing per woman, though it's always a weird thing to say which half of the child is missing. No, realistically, that means every other woman is missing a child that she would have had if birth rates were stable at 2007 approximate levels.

What happens if we go much further back, what was happening with fertility rates in America in the 18 hundreds and the early 19 hundreds?

So pretty much everywhere. It used to be that women had lots more babies. I say pretty much everywhere because there are exception cases. There's sort of unusual ones. Tokugawa era Japan had pretty low fertility. There was low fertility in some parts of the roman empire in the first and second centuries, but pretty much everywhere. I mean, the US had, I think six children per woman in 1800, with the exception of, like, Massachusetts and Connecticut, that were lower, maybe around four. But that number is kind of an optical illusion. We say, oh, they had six children per woman. But the first thing you have to keep in mind is most women didn't survive to the end of their reproductive years. If life expectancy is 30, and we calculate a total fertility rate up to age 50, well, half of women never even make it to the end of their reproductive years.

Oh, so that was a projected rate, not an actual number, right.

Well, it might be true for the women who actually survive, but a lot of women don't survive. I don't know why I'm laughing. That's not funny. That's horrible. But it's a statistical problem, right, that the actual number of children born per woman is going to be much lower because many of them are not going to survive long enough to have six kids. And then, secondly, a lot of those children didn't survive. So surviving fertility per woman in the US was quite high still, probably 2.7 to four ish in that range, depending on the place and the time. But in many societies in Europe, it was much lower, in some places below two, because death rates for children and for women were so high that the average woman hitting puberty really couldn't expect to have that many kids.

It's wild to think that you could get between two and a half and four with all of the hurdles that you need to get over. Risk of mother dying during childbirth, risk of child not making it to maturity, risk of mother just dying outside of childbirth, and still you get close to two and a half or four.

Yeah. I mean, humans have overcome extraordinary adversity. Just before you. Before I got on this podcast, I was writing about the massive population oscillations in the yucatan peninsula over the last several millennia. And, I mean, the result is. I mean, literally, the stories are embedded in our genes, right? Like, you've got subpopulations that they have meaningfully different genes related to how they digest certain foods, or how they interact with certain viruses and bacteria because of horrible things that have happened in their past, and the survivors come out of it fundamentally changed. And so we, as a species, have a variety of adaptations that help us, uh, continue to have children despite all these things. Um, the most important one is that we have very low variation in our reproductive systems. That is to say, pretty much any human can be fertile with almost any other human.

Um, is that common in other animals?

We have a lot of genetic variation, um, that we are still fertile across that in some animals, um, would be more challenging.

What do you mean? Can you be more specific?

Yeah. So, I mean, in some species, you've got groups that are isolated for thousands of years, and when you bring them back to other branches of the species, they basically can no longer produce fertile offspring, whereas human populations that were separated for tens of thousands of years when they get back together, still make babies. What's going on is we have very, so to speak, harmonized reproductive systems. We have very low variation in genetically what's going on with reproduction. We pretty much all do it the same way. There's variation in some of our hormones and a lot of. There's some variation in human body size. But even then, humans have left less variation in body size than most animals. If you look at other species that have wide distributions, they just have more variation than we do. So the upshot of all this is you can survive a lot more things if you're working with a very standardized, or rather, your genes can survive a lot more things if you're all working with a very standardized toolkit. And whoever the survivors are, they can make babies.

Looking at the 19 hundreds, there must be some interesting oscillations and lessons in terms of fertility rate, in terms of desired number of children versus actualized, et cetera, et cetera. As you have people dying, different economic situations, fast crashes and then rebounds, and sex ratio imbalances and stuff like that. What are some of the lessons to take from the 19 hundreds?

So, definitely one of the lessons we've learned is when people are less likely to die, they are in less of a hurry to start having kids, and so they start later. And furthermore, when people believe more of their children are going to survive, they have fewer children, which is to say, people are implicitly targeting surviving fertility. And that explains most of the fertility decline up through, like, 1950 around the world. And even today, a lot of the fertility decline in developing countries is essentially explained by assuming, if you just assume that women are targeting, or families are targeting a stable surviving number of children, that explains most fertility decline. It is the case that surviving fertility rates are actually rising in some african countries, for example, even as overall fertility rates are declining. But in general, surviving fertility is a lot more stable, particularly in that period where you're coming off like early 19 hundreds and things like that, or today for some african countries. But that doesn't explain what's happened in, like, industrialized countries over the last 40, 50 years, because almost all children survive to puberty. It's like 99 point something percent in our societies, so there's not really any leverage there.

And yet fertility keeps falling. So that's not going to be about child survival. We also know it's not about rising standards of living. I have some articles about this coming. They might be out before this podcast. So then people can look them up. But essentially we can see what happens when people suddenly become a lot wealthier but without cultural change. And we can see what happens when whole countries suddenly become much wealthier, but without dramatic cultural change. So for countries, we're often looking at natural resource discoveries, right? Like they find oil and suddenly they're no longer in destitute poverty. They're like wildly wealthy. For individuals, we look at things like lottery winnings or money transfers, and we can see that when you make people richer, they have, they don't have fewer babies, and in fact, typically they have more babies. So what happens is not that societies became richer. We know now that fertility began to fall in many countries long before they were industrialized. In many early industrializing countries, like the UK, fertility did not fall for a very, very long time, and it didn't fall until other conditions were met. So basically, one of the key takeaways that we learned from, particularly the last century, is that fertility decline is not about just becoming a high income society.

We know a lot about fertility, enough now to know that fertility declines largely in response in the long run to cultural factors, not to just becoming a wealthy society.

There was an interesting study I saw you tweet, I actually looked at it off the back of your twitter about fertility rates from lottery winners and swedish people when they win the lottery.

Yeah, we have several studies that leverage lottery winnings. The findings are not all in perfect harmony, as studies never are. But in general, when men win the lottery, they definitely have more kids. That's true across many different contexts. When women win the lottery, there's a little bit more variety. But even then, it does generally seem like there's a, there's a sort of a pro family effect. In the swedish case, it was one of the bigger gaps. That is, there was definitely a positive effect for men, and I forget if it was a neutral or slightly negative effect.

I think women, women get divorced a little bit more likely.

Yeah, there was definitely a divorce effect. I forget what the fertility effect was for women. I will say in Africa, for example, we have a collection of studies recently that showed that when african women have higher incomes, they have more children. And we also know that from studies of american women and american men. So there's definitely some cultural contextualization there, but just in general, I mean, think about any product. Like, if you have more money, will you consume more hamburgers? Very likely. If you have more money, will you consume more airplane tickets? Very likely. Most goods are kind of, you know, consumption of them is going to be approximately related to income. So kids are not different in that regard. If you give people more money, it does tend to be the case that they have a bit more.

Yeah, I think it's an interesting or difficult circle for me to square with modern living standards at the moment compared with how they would have been in 1900 or in 1800 or whatever. Um, the fact that people a lot of the time feel, or say, anecdotally, I can't afford to have a kid.

Even though they're living in the richest society in the world, so.

And they feel like it's true.

Yeah.

Right. They feel like they do not have the money to be able to raise a child. How could I raise a child? I can barely pay for myself. I can't get on the property ladder. And cost of living going up as ever before. And the cost of fuel, and the cost of housing, and the cost of groceries, inflation through the roof and unemployment and all the rest of it. So that is genuinely how they feel, even if that isn't perhaps accurate quantitatively when you compare it with our ancestors. So where's that? Either estimation of the cost of having children or estimation of the cost of how much life is going to come in as an expense. What's going on here?

So one thing to keep in mind is what I said about mortality, that when you actually look at surviving fertility rates, modern people have more kids than people in the past. I mean, human populations in the past were largely stable for a very long time. Now there was a lot of oscillation for hundreds of years of time. But like, there were long periods where for centuries, humans had below replacement rate fertility, okay, in the past, not below 2.1, they were having six kids, but five of them were dying for certain periods. So it's important to keep in mind that the ancestral, primordial human environment that sort of structures the hardware we're working within our brain was an environment where human population was not growing. It was not a growth environment for human population. The 20th century saw massive human population growth. That's unusual in human history. Not quite. Not totally unique, but it's not the dominant experience. Rapid population growth is not the most common human experience. And what that should tell us is that three or more surviving children is not the usual human experience through most of humanity history. So right off the bat, we just have to get out of our head that people in poor societies were having tons of kids.

Right? They were having tons of babies, but rather few of them became kids. Okay? So we just have to keep in mind that, like, humans are targeting the number of children they're going to raise and so on. That sense. Yeah. Actually, the number of children people were raising did rise over the course of the 20th century as particularly the early 20th century, as global income started to rise.

Right. And that's mortality improved. So just, I really want to dig.

And you get things like the baby boom, right? Like the baby boom. There's this massive increase in standards of living with rapid technological innovation in the mid century that led to dramatic increases in wealth, particularly housing wealth. And that's both size of housing and quality of housing. People are living in way better houses. I mean, you look at the things people lived in. I don't mean rich people, I mean, like normal people, like in the late 18 hundreds, and, like, compare that to what they were living in in 1948, and it's just seismic improvement, and they had way more kids.

So just like I say, I've never heard of this before, but it makes complete sense. Are you saying that there is somewhere sort of internally inside of either men and women or just women?

Men and women alike, you are targeting surviving fertility. So, for example, we know in modern and ancient societies, if kid dies, the odds of having another kid rise. Okay? Demographers, sort of maca, in a macabre way, call this replacement fertility, not replacement rate mortality, replacement fertility. So basically, the idea is that humans are shooting for surviving family size. We don't think about it much in our society because almost all of our kids live. But this was very, very, very present in the past. And you see this in the past. In societies where people had six or seven kids, you routinely. There's a problem in genealogical data. You find a kid, their name is John. They die when they're a month old. The next kid also gets named John. When he dies at two, the next kid is also named John. They just keep reusing names because they're just shooting for a john. You know why they want a John? Because dad's name is John and there needs to be a john after the john. Okay? So, like, name repetition is like a really strong indicator psychologically of what's going on.

Wow, that's such an interesting way. You've got this census data or whatever.

Type you get, tax record data, all kinds of things. You've got genealogical data going back a.

Long way, and you've got four kids all named the same. There's no way that you would name four kids that survived into adulthood the same name. It would be.

This is. Yeah. And again, the names that get repeated are likely to be family names particularly. Right. Because you really want an inheritor for the name. So that's the first thing to keep in mind. Okay. Is that it really is the case that, like, modern people are actually raising bigger families often than people of the past. It's not, they're burying more children, but they're raising more of them often. The second thing that's going on is we have to distinguish between standard of living and standard of living. Okay? There's the standard of living in the sense of what you earn. And like, we have a better standard of living. We are more productive, we earn more, we are richer. And then there's the standard of living. That is the standard that if you don't meet it, you feel bad about your position in life. Okay? So if you raise that first one, you can think of it as like, income level. Fertility doesn't tend to fall, and it often rises. But if you raise that other one, that is your expectations about what you should have or what a child should have. Fertility tends to fall.

And what's happening in modern society is yet income has gone up. But particularly over the last 60, I would say especially the last 40 years, expectations have also dramatically risen, particularly in terms of what you'll provide to children. There's a bit of an arbitrary example of this, but I love it. If you look up the frequency of the word parenting in english language texts over time, it's like non exits. It really is quite rare before, like, 1975. And if you look up like other substitute terms like child rearing and things like that, they're also uncommon. But after 1980, the share of english language texts, and this is true in English, English, American English, english fiction, it's true across all textual categories. Legal. It's true in legal cases, like corpuses of legal texts. Frequency of parenting vocab just explodes. In the eighties, nineties and two thousands, we became way more preoccupied with parenting. This idea of parenting, this notion of, like, all the things you have to provide your kids now, I think this actually arguably may have begun a bit earlier than the linguistic shift, but it is the case that there has never been an era as preoccupied with parenting strategies and the things you have to do to raise your children as our current one.

We are what's an indication of.

I think it's an indication. I think it's two things. One, it's just kind of. It's just a cultural meme. You know, there are some societies that did human sacrifice. There are some societies that tattoo their whole bodies, and there are some societies that are obsessed with parenting. So on some level, it's just societies just do things for reasons that are hard to explain. On the other hand, I do think there's a sense in which as children became rare or as childbearing became rare, and as we all developed the expectation that all children survive to maturity, it kind of raised the question of, like, so what should parents do? Like, what are we supposed to do? And I think for, like, the baby boomer generation, the answer was, like, nothing. Like, I mean, we'll put you in a school, put you in front of a tv when you need to be distracted. But, like, parents didn't have to do much. And a nice little indicator of this, you look at, like, the share of mothers who breastfed their children. It reaches, like, rock bottom lows in, like, the forties, okay, forties and fifties. And it's been rising since then.

So in, like, the forties and fifties, I think it's something like 25% of american moms were breastfeeding their children, and the vast majority of kids were formula fed. And it's not. That's bad. Like, full disclosure, I'm a bought and paid for consultant for the formula industry. Like, I'm not saying formula is bad, but I think this testifies to people's views of, like, of parenting as an endeavor, right? That in the middle of the century, it was very outsourced. Right? Outsource the feeding, outsource the education. Just trust whatever the school is offering for your kid. I'm sure it's fine. Whatever's on tv, I'm sure it's fine. Just put the kid in front of the tv. You know, whatever's a church, I'm sure it's fine. They'll do religion. Parent doesn't need to handle religion. That's church's job. Outsource everything, right? So you get this very outsourced model of parenting in the mid 20th century as people just sort of assumed that, like, if you keep the kid alive, everything's fine because that's the goal. Because they could remember a time when kids didn't all live right, and they could see that they were entering a period where if you really tried, you could keep your kid alive.

So they entered a period where it was really possible to keep almost all the kids alive. And they hadn't thought about all the new difficulties that might create. And I think the generation, the baby boomer generation that grew up that way and then also the kind of the gen x generation kind of experienced this very hands off parenting, and it didn't actually go very well for them. That is, they saw that intergenerational cultural transmission was breaking down. Right. That gaps between generations and social values, attitudes and behaviors got much bigger. This is empirically true that this did happen. So we see a much faster pace of social change that caused a lot of people to be like, whoa, whoa, maybe we don't want to do that. And also you get things like rising discourse about fatherlessness, single parents, you obviously get things with drug abuse, whatever.

What was the birth rate during baby boomer generation?

It's a bit over three per woman, I believe, in the US, maybe even almost four at one point.

I wonder whether just adding in another element here, I wonder whether because living standards were rising so much intergenerational competition theory, they were just so much further ahead. So that discussion we had before about expectations versus reality, living standards versus living expectations, let's say the kids are doing great.

We don't need to do any parenting. Like, look how much farther ahead they are than us.

We went on holiday twice this year. I didn't even get to go on holiday at all when my parents were growing up. Because they were growing up during world War two.

Yeah, exactly. So, I mean, that's exactly what's going on is that that generation actually the metrics that they were used to measuring against were met, okay? And then you get, in the eighties, you get the kids who came out of this looking around and being like, okay, that didn't actually go great. Like, we broke pieces of society we did mean to. And also just feeling like their childhood maybe wasn't actually quite what they wanted it to be or that they didn't have a close attachment to their parents. Or like, like, or also as the outsourced, things got more and more expensive. Like, wow, it costs a lot to put your kid in childcare all the time. And also, what happened as a result of this is because children became, in some sense, less similar to the parent generation on average. It meant that there was more heterogeneity in society. Like basically more diversity. And I don't just mean, like, racial ethnic, I just mean, like more diversity in how you think you should fold your laundry. Okay? Like, just, like, it's just more likely that, like, children and their parents or their grandparents just didn't share a view on, you know, what kind of yard maintenance you should do.

Just these little things, like within a family are a little bit irksome. And as a result, you get a generation coming up that's more aware. Wow, the world is really diverse. I can't just trust that whatever's on tv is good. It might not replicate my values. I can't just trust that whatever's in the schools is correct. It might not replicate my values. You get the rise of parenting, the idea that actually we have to protect our children from becoming drug abusers or I.

But parenting is kind of stepping into the natural flow of children just finding it out on their own.

Right, exactly. You're stepping in and you're saying, okay, I can't outsource everything I have to do. I can't just put my kid in school. I have to make sure they get a good education. Now, initially, that means choosing more carefully about outsourcing. Okay? I'm not just going to put my kid in whatever school. I'm going to make sure they get a good school. I'm going to make sure they get good childcare. I'm going to make sure they get good formula for them or whatever. It's this quality idea. But I think what we're seeing now is even more that branded parenting, things like free range parenting, helicopter parenting, gentle parenting, all these, like, types of parenting that people do. Okay, I think what's going on is people realize how diverse society actually is and how they really do want to see certain of their values replicated in the their children. They are looking for parenting strategies that they never learned as a child. Right. Because they just kind of were put in childcare and that was it. They're looking for strategies to replicate their values in the next generation. And the result is that they have a very costly vision of parenting.

Right. Their vision of parenting involves doing all these things. Exactly right. These strategies, these disciplinary modes, like whatever it is, it's like a very long to do list of how to be a good parent. Okay, so I think basically what's going on here is, yes, rising expectations of what your kid is going to have. And then also, as society became more heterogeneous in various ways, more and more parents realized, oh, to make sure to get what I want out of raising a child that is raising someone who's like me in certain valuable ways, I have to do a lot of effort as opposed to cost.

Yes. So that therefore means even if living standards are higher, even if real world money is more available, even if all of the things that economists look at and say, why is it that people think that having children is so much more expensive? They were poorer in the past and they had more children. There is this degree of investment, this sort of expectation, investment expectation going back to what you said before to do with this pivoting in living standards. It was a fascinating study about UBI that just came out recently for the people that didnt get to see that, can you just give a 30,000 foot view?

Yeah. Theres a growing interest in universal basic income, basically just giving people a monthly check for nothing. And some of the big donors interested in it put some money into a pilot project. Okay. Basically, they got a bunch of people, gave them $1,000 a month and survey and kind of did collected follow up data on them. And what they found is for every dollar you gave them, their earnings declined. I think it was like $0.25, so to speak. Their spending rose like 30 or forty cents. Forty five cents maybe. And it rose kind of across categories. It wasn't like it all went to one thing. It rose in like necessaries, like food, and it also rose in like luxury categories, like vacations. Actually, the biggest growth was in gifts. People gave more gifts to other people when they had a UBI. And all the UBI recipients, by the way, were poor. They were all low income to begin with. If you think about it, for every dollar you give, there was a reduction in income, an increase in spending, but not enough to account for that whole dollar. So you would expect that net worth should have gone up.

People should have had more savings then by twenty five cents per dollar or twenty cents per dollar. In fact, their net worth declined by about six cents per. You can think of it as like by six cents per dollar. Kind of net worth is a little more complicated because it's a stock, not a flow. So for every thousand dollars of monthly income, they ended up with about $60 less of net worth at the end. So there's two problems here. One is just like that seems bad. We got success. We got people to work less, spend more, and also not have any wealth building despite higher income. So that's unfortunate. But two, it really raised a question about even the credibility of some of these results. Right. Because you add up, you know, $0.25 less of earnings, $0.40 more of income, a bit less of net worth. And there's a huge residue. There's like a 35 cent residual of like where did that money go? Like, did they just like, did they just light it on fire? Like, did they buy something they didn't want to report, like, something illegal? Did they cut their work by more than they reported?

Did they increase spending on some other category more? So it not only, and they also found, like, there was not a big improvement in housing conditions. There was not, there really were not improvements in. There were not big improvements in almost any category that would, that would be something like, obviously if you give people money, they'll spend more. That's not an improvement. That's just like a thing that happens. So we didn't see improvements in, we didn't see big improvements in, like, objective things that we might all agree are a good thing. And so that should really concern us about Ubi, that it's probably not going to result in great liberation for people. It might just result in, like, more gambling.

Well, a place that people might go to is they might say, well, that's right. Perhaps they haven't got that much to show for it financially at the end of the day. But what happened with regards to an alleviation of stress? And they also looked at that as well. The cash transfer resulted in large but short lived improvements in stress and food security, greater use of hospital and emergency department care, and increased medical spending of about dollar 20 per month in the treatment relative to the control group suggested that the use of other office based care, deep dental care, blah, blah, blah. However, we found no effect of the transfer across several measures of physical health as captured by multiple well validated survey measures and biomarkers we drive from blood drawers can rule out even very small improvements in physical health. And the effect that will be implied by cross sectional correlation between income and health lies well outside of our confidence interval. So people weren't happier, they weren't less stressed, they didn't have improvements.

Again, on any of these measures that are like things we would all universally want, like, if we found a transfer that just made everyone happier and healthier, it'd be like, great, cool. Like, on these measures that are, like, clearly good outcomes. Yeah, they found nothing. It didn't help people at all. There was another study, a different study that looked specifically at home that gave a UBI specifically to homeless people. And the goal was, we will give them $1,000 a month to find housing. And they found in the long run, there was no across, I think it was three year follow up. After three years, there was no difference in the homelessness rate of people who got like $0 or $1,000 a month. Simple reality was that giving homeless people money did absolutely nothing to get them in house. And a lot of money a month, you can pay rent for that for one person.

Is that not something to do with the culture or the lifestyle or the substance dependency that these people have kind of being a lingering overhead that doesn't allow them to get the exit velocity to get out of the bottom of homelessness.

Yeah, there's. It would be easy to look at these UBI studies and say, what these tell us is that nothing helps. The poor are permanently poor. That is, in fact, not what they show, because we actually have a lot of interventions we do know. Work focused substance abuse. Substance abuse interventions, like getting people in rehab, getting them support, stuff like that, does cause people to be less poor. High quality therapeutic interventions, like based on cognitive behavioral therapy, not low quality random talk therapy things, but high quality therapeutic interventions can actually boost people's long run income and health. Certain religious interventions are actually known to boost long run income and health. There are a lot of things that we can do that do lift people out of poverty. Education, obviously, handing them cash turns out not to be one. It just isn't. So, yeah, it is the case that if you are a donor and you have $20 million that you want to spend on helping poor people in the US, let's say you would be way better off investing that in focused substance abuse treatments, um, than a UBI. Okay. Giving cash doesn't do a thing for long run outcomes.

It actually does.

Briefly. Briefly, it does. Right. A change in income is a better predictor of happiness than absolute income. Like, eventually everything normalizes until you disequilibriate it again.

Yeah, so, but I mean, the point is, like, if you actually want to alleviate poverty, not just for the next six months, but actually lift people out of poverty, Ubi is just not the way to do it. It just isn't. And at this point, we have decades of experiments and pilot studies and all these things. Looking at this, we know that this doesn't work for long term poverty alleviation. Now, there are things that are somewhat similar to UBIs that do work. So conditional cash transfers. So, for example, child allowances. Sometimes when people really want to argue against child allowances, they will sometimes call them UBIs. They are not Ubis. Not everybody gets them. You don't get them forever. You get them conditional on something that is having custody of a child. And it's important to mention having custody, okay, like, people who are the genetic parent of a child, but not actually, like, in the same tax unit as them don't get a child allowance, right? So when we give people a child allowance that rewards them for actually raising their child co residentially, that's good. Okay. It generates slightly more children and it generates slightly less divorce and it generates a slightly more spousal or co residents of partners.

We know this. We have decades of studies showing this. So Ubi, where you give people money for nothing, not a good policy. Conditional transfers, where you give people money for something can be a decent policy depending on what outcome you're targeting and what you're trying to do. It's still expensive, but its important to distinguish between UBI, which now I think we really should be able to put this to bed, that its not a good idea, and conditional cash transfers, which may in fact be very worthwhile.

So when we get back to the fertility rates and where were at the moment, what are people saying, modern people right now, about the number of kids that they do or dont want and their reasons for wanting or not wanting children?

In surveys like in the US, for example, people report that their ideal number of children is 2.3. If instead of ideal, you ask them to rate how happy they would be with different family outcomes, like 012-3456. Whatever. People's sort of weighted average happiness tends to be about 2.3. If you ask people what the ideal family size for a family is, their average tends to be 2.3. Any way you ask, that's getting it. Desires, wants, ideals. For the US, it's 2.3. If you ask about intentions, how many kids you intend to have? That's a very different question. That's not asking what people want, it's asking, okay, down to brass tacks. Thinking about your life as it really is, it's almost like asking people, how many kids do you think you can afford to have? Okay, all of us would recognize how many kids can you afford to have? Is not the same thing as how many kids do you want? Okay, how many kids do you intend to have? Depending on the population subgroup and the exact survey and all, it ranges from like 1.85 to 2.1 in the US. Actual fertility in the US is 1.6. So people are way short.

They're about 0.7 kids short of what they want, and they are about 0.2 to 0.4 kids, 0.2 to 0.5 kids short of even what they think they're really realistically gonna have. They are. They are. They're not even meeting what they think of as like their realistic goals.

And presumably the number of when you look at actual fertility rates, that's people who've had kids so far. When you ask people what they intend to, that's future focused and given different ways. Yeah, but given. Given that we're on a decline in terms of fertility, we can assume that the number of actual children is going to continue to move away from that number of intended children. So I get that. But that Pew research that came out recently, like, ten percentage point increase in the number of people under 50 saying that they didn't want to have kids, 37% to 47% between 2018 and 2023, what do you make of that? That's nearly 50% of people under the age of 50 saying that they don't want to have kids, unlikely to ever have kids.

So the actual prevalence of young people who say they don't want to have kids was 20 something percent. The 50 something was like the share of. The share of childless young people who say the reason for being childless is because they just don't want kids. So say, okay, among childless people, what share? Just don't want kids? The actual share who say they don't want kids is like, maybe 20 ish 2020, 5%. That sounds high. It's similar to what I find in my surveys that say we do inhabit a society where the average person wants 2.3 kids, and also where 15% to 25% of people say they want zero kids. We are inhabiting a society of increasingly polarized desires, where there's people more and more clustering at zero and at, you know, three or four. Not a lot of people saying, like, six. So, yeah, it is what it is long run for fertility. You know, you can have a society where everybody has two, you can have a society where half the people have zero and half the people have four. They both have a fertility rate of two on average. So what we're seeing is, yeah, there is some rise in intended childlessness.

It's largely offset by rising desires for big families. On average, desires haven't changed a lot. And what we can see is that the fertility decline we've had over the last 15 years, it's bigger for unintended births. That is, unintended births have fallen. I think it's like 40%.

What's unintended births?

Births people were not trying to have. So they were not planning to have a kid, and they did, whereas intended births have fallen, I think, a bit less than 20%. So, yeah, there's been a bigger decline in unintended births. Meaning that. Meaning you can think of that as like people avoiding having kids that they didn't want to have. That would be consistent with the idea that there's more people wanting to avoid have kids and successfully avoiding. But we've also seen a decline in intended births. That is, people who do intend to have kids but are having fewer of them. So I don't worry too much about a growing share that say they want zero, because, okay, that's fine. You can want zero. Other people want four. Other people want two, on average. It doesn't seem to be changing a whole lot.

You seem surprisingly positive, or at least non apocalyptic, given most of the demographers and the people in this world that I'm speaking to have this cataclysmic perspective. It doesn't seem to. The alarm bells don't seem to be going off quite as aggressively. Or maybe you're just holding it together.

Well, you know, falling fertility is a very serious problem. It is. It's a problem. To my view, the biggest problem of falling fertility is I want people to have the lives they want to have. I want to live in a free society where people are free to achieve reasonable, normal, and acceptable life goals. Two kids, that's a totally reasonable life goal. People should be able to achieve that. If they can't achieve it, that's a serious problem in society, in my view. It also happens that low fertility has really bad economic effects in the long run, as bad political effects. It has all sorts of bad effects the long run. Those are less of a concern to me. Um, because first of all, I think it's kind of gross to use babies as, like, your instrumental solution to GDP. Like, have a baby for the. GDP is, like, not a great pitch. Or, like, have a baby so we can recruit them into the army. Like, not a great pitch. So to me, the biggest issue is just people not getting what they want. So if people genuinely want zero, like, that's not my problem. I don't want zero.

I want five. So I want to be able to hit five. I want society to not put obstacles in front of that because we are below desires on average. I'm very, very strongly in support of pronatal policy. I think we should be doing a lot more to help families hit their goals and offset some of that standard of living issue. But, and this is what I think is really important. You're right. There are a lot of people who, like me, are pronatalists. That is, they want to see more kids born, and they do adopt this really apocalyptic tone. It's a fertility crisis demographic winter Koreans are going extinct. And I think that that tone is just a massive mistake. The best predictor of people not wanting kids is depression and anxiety. Okay? If you want to know if someone wants to have kids, ask them to rate one to ten how happy they are. The number they give you is going to be wildly correlated with the number of kids they want to have. The strongest predictors of low birth rates at the individual level are fertility preferences and measures of mental health. People who are depressed, anxious, uncertain, sad, worried about the future, they don't have kids.

Why? Because the reason you have kids is to raise them and watch them become fruitful adults. And if you think that the future is scary and bad and awful, then you're not anticipating the joy of children. You're anticipating watching your children suffer in a bad world. Okay? So my view is that if you actually want people to have kids, shut up about a crisis, okay? The only way to get more kids is to convince people that the future isn't awful.

The birth rate decline is downstream from a mental health crisis.

It's definitely related to it. So, I mean, yeah, this is, you know, there's these like, broad structural things about, like the standard of living people expect, the standard of care they expect for kids, all these things. But there is also very concretely, yes, a mental health crisis. I mean, pick your condition. I mean, depression, anxiety, autism, schizophrenia. I mean, these are very different conditions. Or just like survey reports of sadness, survey reports of uncertainty, survey reports of beliefs about if the future is going to get better or worse, negative affect across all of these indicators associated with lower fertility preferences and lower fertility behaviors. Categorically. My concern is that some very well intentioned people talk a lot about the fertility crisis, and they are sabotaging efforts to address the problem of low fertility and the problem of people's fertility not meeting what they want. Because by talking crisis, crisis, crisis, crisis, we're telling people, look, if there aren't more babies, the future will be very bad. Okay, but think about what that says. Somebody says, okay, so then I shouldn't have a baby.

You should bring your children into this world. That's reliably.

And also, there's no way I can guarantee other people will have babies, don't have a change the social fertility rate. I can only change my own fertility rate. So if I see that other people aren't having babies, I'm not gonna have babies, because a world of low fertility is a world of bad outcomes, and I don't want to bring my baby. It's like, it's this like vicious cycle where like, because people are so convinced that like of doomerism they don't have kids and then the pronatal people come out and tell even more doomery stories when what we should say is like, look, look, if you individually have kids like desired children, this isn't as true for like unintended children, okay? But people who want kids, when they have kids, it's associated with very positive outcomes. They have higher happiness in the short run. They have higher happiness in the long run. Ten years out, they're happier than otherwise similar people who wanted kids and didn't have them. People who want kids and don't have them have higher rates of prescription of antipsychotics, anti anxiety, antidepressants, they are more likely to have adverse, quite adverse mental health outcomes.

People who want kids and have them report just a whole range of better life outcomes and people who want kids and don't have them report considerably worse subjective well being in the long run. Now for people who don't want kids, it's a different thing. Okay. Not, I'm not, you know, I'm not trying to bully anybody to having kids that they don't want to have, but there are so many people that want kids and they're not having them because they're worried about this, that and the other. And we just need to say, look, first of all, we know in longitudinal surveys that when people have kids, they increase the number of kids they think is ideal. So think about what that says. Once you have the experience of having kids, you decide you want more of them on average. Okay? So like, my, my encouragement to people is like, kids are going to be way more fun than you think. Like, they're going to be way more interesting than you think, they're going to be full of way more value than you think. And once you have them, you're way more likely to be like, I kind of like to have more of these than being like, dang, I would have preferred fewer.

That latter response, it does happen. People do say that in surveys. There are people who say, you know, I love my kids, but if I had it to do over, you know, I might have one less. There are people who say that it's not, it's not never, I'm not going to say that never happens. It does. But on average, people who say, you know what, I had these kids and wow, yeah, I'm totally raising my number now. Way more numerous.

Have you had a look at retrospective regret of childless people? What is there to learn from that. How common is it?

So actually, the, the Pew survey you mentioned has some surveys on, has some stuff about this. They didn't ask it exactly, but, yeah, I mean, childless people do report various difficulties arising from childlessness. Crucially, the Pew survey asked young people, do you expect such and such a thing to be a challenge with childlessness? And then they asked older childless people, was such and such thing a challenge? And they found that across numerous categories, the challenges were more common than the young people expected. What.

What sort of challenges?

Um, you know, feeling disconnected from the next generation. Feeling like you lost friends because you didn't keep up, you didn't have kids. Um, feeling like, um, you were lonely, feeling like. I forget the list they had. They had a bunch of these different things. And across the vast majority of them, current people who don't want kids were underestimating just how big the difficulties, challenges and regrets can be. That doesn't mean that childless people all regretted it. Many of them didn't. But, but it is the case that young people are greatly overestimating the benefits of childlessness, so to speak, or the costs of having children. Or maybe they're underestimating the benefits of having children, however you want to put it. It is the case that when people get to retirement, that free solo life is just not going to be as good as they think it is.

What is the relationship that you see between marriage rates? Desire to get married, mating crisis, desire to get into a relationship, and desire for children and stuff. Does this piece together in a nice, neat fashion? Does it make a cohesive narrative or is it individual things going on?

So fertility of married people has not declined nearly as much as the fertility of unmarried people. And crucially, the main thing that's happening in fertility is just that people are not getting married as much. Okay, they're getting married later or not at all.

But are people not getting married because they don't want kids before they get into a relationship?

No, because we know that desire for children is approximately stable. Right? So we know that. We know desire for children is approximately stable. We also know desire for marriage is approximately stable. About 90% of people say they want to get married, most of them in their mid to late twenties. That's the typical age, which is a bit younger than actual marriage ages right now. So we know that that's what people want. And yet marriage ages are rising and rising, and a growing share of people will never marry. So we're actually seeing a shortfall in marriage versus desires. Okay. People who get married, their fertility rates are not declining that much. Not declining as much. And if everyone got married at the same rates they did in 2007, fertility would not have declined nearly as much. Most of the decline is just because of less marriage. Okay, so yeah, a mating problem is a huge part of the story. And there are so many reasons people are not marrying as much as they used to. I mean, one of the biggest ones is just an economic change. It is the case that if you look at data from dating apps, women swipe on men's incomes at the same rate that men swipe on women's conventional physical attractiveness.

I'm not sure you can say that says something bad about us as a species, if you like. It's facts. It hasn't changed in, you know, 2000 years. Actually, let me take that back. It hasn't changed in 600,000 years. So status will always, men's status has always been fertility correlated. It just always has been. It's always been the case. There's virtually no exceptions that high status men, high income men in money societies have more kids than low status men. That being the case, you have to ask what not. What has happened to men's income generally? You have to ask what happened to men's income at the marriage ages, that if you get married in those ages, it's easy to have two or three kids. So that's going to be marriages in your twenties. If you're not married in your twenties, odds of getting to two and especially three kids decline. So what has happened to the income of men in their twenties? In the US at least, it has actually declined over the last 20 years, 30 years, men in their twenties are actually getting poorer, inflation adjusted terms. This is not true for men generally.

This is not true for older men, this is not true for the population generally, people are getting richer, incomes are going up. But for men in their twenties, and that's the group for whom income is sort of setting the bar for marriage because I'm assuming that women in their twenties are not getting less attractive or something. Okay. And again, these are not the only things that guide marriage. Obviously, what really guides individual marriage is like love and like shared values and shared life orientation. But funny enough, people tend to fall in love with people who are within a certain socioeconomic band of their expectations and within a certain range of. It sounds so callous to say, but like physical attractiveness, yes. Individually, people marry for love. Collectively, humans don't. They marry for other things. So it is the case that men's marriage ability in the key marriage ages for supporting fertility has declined really, really sharply. That is, their incomes have fallen, particularly compared to women. That being the case, there's less marriage. And in fact, marriage rates and particularly fertility rates have declined at exactly the ages where men's incomes are declining so early in mid twenties.

And at the ages where men's income is rising in the thirties and forties, fertility rates have actually risen. There actually has been an increase in fertility at those ages. Not enough to offset the decline in earlier ages, but a little bit. So basically whats going on with the marriage market on a deep level is that young men are poor. They cannot support a family, particularly a family whose consumption expectations are set by, by like the joint incomes of two single people with no kids. So if you spend your whole twenties setting your consumption expectations based on zero care responsibilities, your parents are still young enough that you're not having to take care of them in old age. You don't have kids, you don't have a spouse or something like that, and then you come into marriage and that's how your consumption expectations have been set. Well, it's really hard to have kids.

You mentioned before about this decline in unintended kids. I know that you've looked recently, and I've been doing quite a bit of research into this too, about the attitudes toward contraception in the US. I think if I was to put a couple of bets on a roulette table for upcoming public health furor things that people are going to be really, really concerned about. I think we're already sort of starting to see a lot of women talk about the psychological challenges that come from hormonal birth control, physiological changes, things that you can lock in for the rest of your life if you take it during puberty and periods where the brain is in development. I also think microplastics in water, I think toxic environments, molds, etcetera, is also going to be another one. But it's surprising to me that it seems to be this. It seems to be two things at the same time. It seems to be both a very pro contraception and a very anti contraception culture. I don't know whether that's just two different cohorts. And I get to like hear the most vociferous of one and the most vociferous of the other, but do you know what I mean?

There's this sort of superposition I'm in.

Yeah, everything natural except reproduction. Right? That's, that's the vibe, right? All natural except reproduction. So I think that's a real thing on the fertility front, you sometimes hear things about falling sperm counts or falling testosterone counts. This is basically fake. Sperm counts are not falling in scientifically studied cohorts. And anyways, the actual effect of the kinds of variation in sperm, sperm counts we observe, the implication would just be you need to have sex for an extra two or three months to have a child, not that you would become infertile. Testosterone changes are a bit more complicated because there's just measurement of testosterone is extremely problematic. Problematic instance like, it's very difficult and it changes over the course of the day, and it changes in different parts of your different types of tissue samples or cell samples. But either way, these kinds of things don't appear to be affecting fertility. Microplastics. There are some plastics that could impact fecundability. So far a couple studies have gone looking and have not found anything, or at least not anything significant. But it could be. I mean these things last a long time, so it could be that it takes us a few generations for them to build up in sufficient levels to do damage.

Um, uh, in general, and in contraception, um, the best evidence suggests that hormonal contraception can increase time to pregnancy after cessation, um, by a few months. That is, it can take a few months longer to become pregnant, um, and for some methods it can be a lot longer. I think long acting reversible contraceptions, like implants, can increase time to conception bye. By quite a few months. There doesn't appear to be long term identifiable damage to fecundability. The problem with all these studies is that people who choose to use more intense contraception are also people who want fewer children. So even when they go off contraception, they have fewer children because the reason they were using contraception is because they're people who want fewer children.

Have you, have you found any research looking at how what women's desire for children, desired number of children, intended children, changes when they're on or off birth control?

I haven't. I know that there's some stuff that's, I don't know the state of the research on this, but I've seen headlines saying that like, when women are on certain forms of hormonal birth control, that like the type of like body type that they will swipe on on dating apps is different or something. I dont know how credible that is. In general, Im skeptical of most of these types of findings for a variety of reasons. One, we have really good controlled studies that look at time to pregnancy, and we can see that for couples who are not using contraception of a given age and actively trying to conceive. Time to pregnancy hasnt changed in decades. As far back as we can study. It just isn't the case. The time to pregnancy has changed. People's ability to conceive hasn't changed a bit. So in time to life, birth hasn't either. That is implied. Miscarriage rate has not changed. So that tells me that whatever's going on under the surface, it's not dramatically altering fertility. There could be things on mate selection. I would totally believe that the rise in. But honestly, contraception wouldn't be the main thing I'd point to.

I would point to the rise of SSRI's and other antidepressants, anti anxiety, antipsychotics.

Because they more directly impact the brain.

The share of the population, or I mean, frankly also just drugs like pot and opioids. There are so many other substances that would be my go to on if something is messing with mate preferences. Preferences. What could it be? Maybe the really, like quite powerful drugs that are designed to alter your neurochemistry. Like, let's not say those things are bad. Like, I don't know if anyone's ever studied what they do to mate preference. They do alter libido, obviously, but I don't know what they do to mate preference and things like that, or views of commitment. And also, like I said earlier, that like, depression is itself, um, sort of anti natal. So like you could find that like antidepressants are antinatal, but they're less antenatal than the depression.

Depression is.

Oh my God.

So funny, right?

So like, you, you could get these kinds of really interesting challenges.

Yeah.

And so I just, in general, my view is like, we live in a chemical soup. We just do. We always have. In ancient times, they weren't chemical soup, it was just that humans were so hungry. They were just, I mean, you look at old cookbooks and they were eating stuff that today, you know, 20% of the population is allergic to and it smells like death and like, it's awful. But they were eating it like twice a month. Or like, I mean, you look at the, there's something called the eastern agricultural complex, which is pre corn agriculture among native american tribes in the eastern us. And like, you can look it up, there's all these crops that you're like, what is this crop? And I kept telling my wife, like, I really wish, I really wish there was like a restaurant that would like, like a hipster restaurant that would like use only pre columbian crops and animals, like have a whole menu on it. I was like, this would be a cool idea. And then I looked up the crops, and I was like, okay, so, like, this one has, like, an aroma that can be smelled down the street when it's cooked.

Like, this one has great proteins. It's, like, better than quinoa. Also, like, everybody's allergic to it. Like, so many people are allergic to it. Like, they're. They're awful plants. Like. Like, there's a reason that as soon as Native Americans got corn, they were like, yeah, I want corn. Corn's amazing. So, like, one of the things we don't talk about with, like, the great diversity of crops that people used to eat is that, like, so many of them were really bad and, like, bad for you and unpleasant. Or maybe they're good for you, but they're unpleasant, or they're pleasant, but they're bad for you. That's not to say declining crop diversity isn't a bad thing. It is, like, we should preserve rare.

Varietals, not the ones that stink the street out, though.

Yeah, exactly. Like, I would be okay if Durkheze. Do you know about dairy? Are you familiar with Durian?

Yes. Yeah, that stinky fruit.

Yeah, I'd be okay if it went extinct. Like, I know, like, all of Asia cries out in horror at what I just said, but, like, that one, I wouldn't mourn. But. But by and large, like, humans have always been putting just weird stuff into their bodies. And so I think we are less fragile than we think we are. And we talked at the beginning about how humans lived in environments where so many people were dying, and yet they still carried on. And I think we're less fragile than we think we are. And to be honest, this is actually part of what I think is part of the cultural change we need to promote. Fertility is like, kids are not as fragile as you think they are. That standard you think they have to have, they might not need that standard. They might be tougher than you think they are. They might. Can just be okay playing outside some. You might not need to intensively do every little thing. And beyond that, you are less fragile than you think you are. Children are not going to break you. You're going to be okay. Some people won't be.

Most people will be. You are going to be okay. You are less fragile than you think you are. You can do it. You can raise kids. You can parent. You will pull it off.

Does political polarization play a role here? We recently came out of the DNC, where they were offering free vasectomies and abortions outside, I think. But what about the role of polarization in political beliefs, parents wanting their kids to date somebody from within their own political class, the increasing importance of politics in mate selection and in people's lives than perhaps it used to previously.

Yeah. So politics plays a role in a couple of ways. One, political cultures are sets of ideas and values and memes and norms and behaviors and social ties. The fact that one side of politics, in the US at least, has adopted particularly antenatal social values, that is, I mean, if you. A great example of this is like the average fertility rate of republican elected officials at the federal level is something like 2.6 kids, and the average fertility rate of democratic ones is like 1.4. So, like, there's like microcosm right there. Right? I. Interestingly, that means that democrats are closer to the societal average. So republicans are the weirdos, but they're like the weirdos continuing humanity. So I do think this is unfortunate that we kind of have this perpetuating political culture on one side that promotes norms of anxiety, fear, and uncertainty about children and presents children as burdens, primarily. Let's not say Republicans are innocent. There's a lot of ideas and values on the republican side that I think are antenatal in a little bit more of an oblique way, particularly norms around work. For republicans, everything is about jobs. If it makes jobs, it's good.

But I'm like, if you employed a moment earning minimum wage, like in her alternative was staying home with kids or a dad, it could be a dad as well, though in practice, statistically, it's usually mom and she has two kids. It's probably more socially valuable for her to invest in her kids than flip burgers. I'm actually not interested in creating make work jobs just to pull people away from their families because I want to buff labor force participation. That's just not what I value in general, just the super work focus that republicans tend to have, I think is a cultural mistake. Work is rivalrous with family on some level. So at the same time, I do think it's worth remembering that political culture comes from somewhere, right? We know that depression is not equally distributed across the parties. We know that certain types of fears about the future are not equally distributed across parties. And as a result, I don't know how much we can blame partisanship for what might actually be a difference in religiosity or family background or mental health or a million other variables. Right? Is partisanship causing this, or is partisanship just reflecting that this is the kind of divided society we live in.

Wow. Yeah. Well, I mean, increasingly fewer people are disbelieving about the heritability of sort of psychological dispositions, whether that be introversion or extroversion or conscientiousness or willpower or fucking hunger or political ideology. Some things that are more complex, which are an entire sort of suite of dispositions that all come together. But this is the. Every time that I see it, every single time that I see an antenatalist movement that intends on continuing, it blows my mind. It's like what you. This is mating, seppuku.

Do you know how things work?

I just do the thing outside of the DNC. I'm just going to make this plain. For the people that haven't seen the previous episodes, your political affiliation is heritable. That means that if you are a card carrying, dyed in the wool Democrat, it is more likely that your children will be Democrats as well, because there is a particular suite of traits, personality types and dispositions that have led you toward that. You can take personality tests for both Republicans and for Democrats, left leaning, right leaning, labor, conservative, whatever it is, and people will veer in that kind of a direction given that your children are made up of the raw genetic material that you're about to give to them. If you are someone who wants your particular political ideology to keep moving forward and you do not have children, that is you basically ceding ground to the side that decides to have children. And it just, every single time that I see this, I'm like, is it, do they not know that this is the case? Do they know and not care? Are they so short, short term minded that they think, yeah, but we're going to buff Kamala's votes by 0.1% in a key battleground state by doing the vasectomy outside of the DNC truck.

I don't know.

I think there's a couple of things going on. One is they're betting on the power of conversion, right? Because most people, you think about the dynamic here because more socially conservative people have more children. A disproportionate share of children are raised in conservative environments, and yet we end up with relatively even politics. How? Because conversion favors Democrats. Okay, so the democratic party is disproportionately made up of converts, so to speak. People raised Republican and became Democrat. And as a result, it's going to be people who selectively believe in the cultural power of conversion. Right. And I would say they're not actually entirely wrong. So I've done a fair amount of writing about this recently that heritability of fertility turns out to be very complicated. It's true. If you have a norm that leads to zero fertility, okay, that weeds itself out relatively quickly unless it has a reason for people to select it for fitness in the time being. If there's a norm that gives you zero fertility, but also it just hacks the part of your brain that handles dopamine, you'll choose it every time, and eventually the species will just go extinct. Like, species can just go extinct.

Like, it's not inevitable that, like, fertility is 2.1. We could just stop having babies and go extinct. And there are pieces of your brain that can be hacked through, you know, drugs, through medicine, through, you know, congenital defects, through whatever. Like, yes, dopamine receptors can get fried. People can become addicted to things that kill them. People can. It is possible that we could just stop breeding. There's no reason that fertility has to return to two. And I've actually run a lot of simulation models on this that, like, let's say you have, like, the Amish, okay? Are the Amish ever going to become a majority of the population? The answer is absolutely not. They never will. If all you do is you take actual real world amish fertility over the last 50 years and trend it forward and use real world rates of conversion in and out of the Amish, you find that the Amish are going to peak at a maximum of like 7% of american population, and they're never actually going to get there. The simple reality is conversion is really powerful and assimilation is really powerful. There is not for simple monogenetic traits that do, that have certain types of fitness profiles.

Genetic drift can be really powerful, but most traits aren't like that, particularly if they're polygenic. For example, politics, I mean, height is quite heritable, okay? Like heights, very heritable. Like, it's like 80% heritability. And some behavioral traits are quite heritable. There's debate about schizophrenia, but it appears to be relatively heritable. Okay? And it has behavioral implications and stuff like that. Social values as a family set, which includes both politics and religion, is like one of the least heritable trait sets that we know of, along with reproduction, ironically, I mean, religion is actually highly environmentally sensitive, right? The reason kids born in Saudi Arabia become Muslim is not because they have a muslim gene, right? It's because they're in a context that encourages Islam, okay? And we know this because kids get adopted across countries and they're astronomically more likely to end up in their adoptive parents religion than their birth country's religion. Like, korean kids adopted in America don't become buddhist, by and large. They become like, you know, Presbyterian, although there's a lot of korean Presbyterians, too. So in general, social values, they do have a heritable. I'm not gonna say they don't have a heritable component.

They absolutely do, depending on kind of how you define heredity, because that's complicated. And. And what social value you're talking about, it ranges from, like, 3% heritable to, like, 40% heritable. That's kind of the range you're talking about. There aren't a lot of social values that are over 40% heritable, whereas there's a lot of physical traits that are considerably over 40% heritable. And then you get traits that are kind of like a medley of the two. So you think about things like sexuality, the super controversial one, intelligence. There's huge debates about heritability of these, sexuality is highly non heritable. For example, there's some genes that do relate to it, um, but probably through gene environment interactions, not directly gene. Um, the upshot of all this, I'm kind of meandering the upshot of all this is that, like, conservative fertility advantage does drive some electoral advantage, but way less than you would think. Way less than you would think from just like a naive sort of breeder's equation type of population genetic model. Um, it really is the case that the heritability rates are sufficiently low and conversion rates sufficiently high that they're. That conservatives don't get nearly as much electoral bang as you would expect from their fertility buck.

And their fertility buck is large. It's a very large fertility gap between Republicans and Democrats. And in a pure hereditary environment like this would be the last generation of Democrats to have an electoral shot. But we all know that's not what's going to happen. We all know that politics are going to remain highly competitive, and Democrats have the same thing where they're like, look at how conservative young people are, or look how liberal young people are. This is the last time conservatives will have a shot. And yet here we are. They think that every generation, and it's still the case that politics are competitive on the same issues that they always have been. So I would strongly caution against trusting to fertility. To give your cultural group a long term majority, you really do need to persuade other people.

You meaning that you can't shag your way out of some ideological cul de sac?

Probably not. You actually need to make persuasive arguments.

God damn.

So, so you know, I think, you know, vasectomizing everybody who walks into the DNC, whatever its net social benefits or costs, it probably doesnt have a huge effect on long run political equilibriums.

Okay, what are your predictions for the sort of future of western fertility rates and stuff at the moment down. Its going to continue. I mean does it bottom out? It has to. Presumably at some point it's going to be carried by certain small subgroups that.

Would maintain it could bottom out at zero. If you think about, let's imagine, okay, let's just do doomsday scenario. And it turns out that microplastics totally sterilize people. Okay. Microplastics are also totally inescapable. They're literally in the air. Unless you are wearing a hazmat suit, you are getting microplastics in considerable volumes. So if microplastics cause sterility, then western fertility will bottom out at zero. Okay. On the other hand, if low fertility is caused by, if falling fertility is being caused primarily. Bye. I don't know, pick your pet theory. If it's caused by like particular parenting norms. Parenting norms are something that probably could weed out fairly quickly in just a few generations. Okay? They're going to be highly volatile. They're not. We know that they can be broken across generations because that's what has happened recently. And we know that people with parenting, specifically parenting normally, that encourage more children, that seems of values that seems more likely to have high heritability like 0.3 or something than low like 0.1. Okay, so like if parenting norms are what's driving low fertility, then maybe in 150 years we're like back up to.

Two people's expectations about the amount of investment that's required in a child.

Yeah. And people who are raised in like lower expectation environments will, will, will make up a larger share of the generation. And I don't think there's a compelling reason to think that like super high expectations parenting is necessarily always going to be super persuasive as a conversion prospect. So on the other hand, you can get things like, if it's really just that like young men's incomes are crap, that's not likely to go away because skills, biased technical change in the economy is what it is. You need skills, it takes a while to get them. It is what it is. So that might not necessarily go away, but that also wouldn't cause us to flatline at zero. That might cause us to flatline at one or 1.2 or something. So I tend to think that stuff like skills bias, technical change is a decent explanation for those types of structural economic factors and also things like parenting or decent explanations for what's going on with fertility. And I don't think the more apocalyptic explanations are reasonable. And so I think that we're likely to see continuing decline for quite a while. I think we'll bottom out somewhere between 0.4 and 1.3, and then maybe there will be social subgroups that find ways to achieve higher fertility.

Whether that will be heritable will remain to be seen. Fertility heredity requires stable transmission of the same traits across lots of generations to do the work. There's only one gene that's known to have long run positive selection across a long time span. So I'm a little. I'm just skeptical that we're going to suddenly find a new gene that, like, drives super strong positive selection. Maybe we will. Right now, we can see that positive selection for fertility across cultures is happening across 50 or so gene. Gene, genetic loci. But it's not the same ones in different cultures. It's not, like, all western. And this is just among. Just among european societies. Among western european and american societies, there's 50 or so genetic loci that are among active selection, but there's only one genetic loci that's under active selection among, like, all groups, and it's been under active selection for 30,000 years, and it's still only 66% of the population. So, like, give it another 500 years, it's still going to be, like 66% of the population. So other than that, like, there is genetic. There is selection on fertility happening in different societies, but, like, dutch people are breeding for or, like, selecting on different genes than american people and different than estonian people and different than swedish people.

It's different. We're not gravitating towards, like, it's not like we're finding a gene that, across populations, is, like, predicting higher fertility. So I'm skeptical we're going to find a new one.

What is a medium term future with an upside down demographic table look like? What will it be like to exist over the next, going from wherever we're at now, 1.6 to somewhere between 0.4 and 1.3?

Yeah, it's going to be a lot of disappointment and a whole lot of cope. So disappointment. There's going to be a lot of people not having the families they wanted to have. That will lead to various coping mechanisms, trying to encourage the younger generation not to make the same mistakes, which might be an endogenous method of fertility increase, or just being angry at the next generation because you feel no attachment to them, which could be an endogenous mechanism for continued fertility decrease, disconnection between generations, sadness, insisting that you're not actually sad. You never really wanted those kids anyway. People have different coping strategies, but it's going to be a sadder and more disappointed society. There will be reduced entrepreneurship, reduced pace of technological innovation. There will be reduced economic growth rates. I mean, we've lived in societies with zero population growth before they were called feudalism. So we will see more inequality, greater concentration of wealth across generations because estates will be divided among fewer people. I mean, it's unpleasant. This is why people talk about a fertility crisis, as we've already discussed. I really dislike that language, and I think humans have survived unpleasant environments before, for life in a low fertility future will be worth living.

It will be so worth living as human life has been for hundreds of thousands of years. So. And crucially, the main obstacles to having kids are likely to be psychological. That is, if you can get over the burden of, like, being, like, married, younger than your friends, not going on quite as many international trips as your friends, and, you know, adopting strategies conducive for mental well being, you'll probably have plenty of kids.

It's going to be an interesting period. The cope thing, I think, is going to occur on an individual level, but it's also going to occur on a macro level as well. It's so. I don't know, because I live in this weird, degenerate Internet subculture niche world as opposed to normie world. But people still talk about an overpopulation problem. They talk about population boom, about limited resources, about us running out of space, about us running out of energy, about all of this stuff. And there are going to be all of these things that come along for the ride. Population decrease is going to result. Unless we have some unbelievable automation and AI robotics stuff that comes in to save the economy, you're going to have to have a reduction in economic growth. Okay, so what's that going to cause? There's going to be a lot of people that are very unhappy and start pointing fingers all over the place. And you go, well, the policies that you were putting in place only not so long ago are the. These are the fruits of those exact suggestions. And now it's something else. It's something else is going on for you to complain about.

So, yeah, I'm concerned, quietly concerned. I'm not as equanimous as you are. Although I'm actually feeling a little bit better after today's conversation. What's next when it comes to studies? Where is your focus going to be over the next year or two?

So, right now, I'm the director of the pronatalism initiative at the Institute for Family Studies. And what we're focusing on right now is housing. Housing is a major milestone for young people. It's one of those. One of those things that people tend to think like, you shouldn't have kids until your housing situation is kind of sorted out. And young people are getting less and less likely. They're living in smaller and smaller houses, and they're less likely, less and less likely to own their houses. And so we are exploring what can be done about that. How can we make housing more affordable? How can we make it a more useful method of long term planning for young people? How can we make it more accessible to them? And what types of housing are most supportive of transition to family life? So we're doing a lot of original research there and hoping to release some of that over the next few months.

Dude, that's cool. That's cool. I'm a big fan of the institute for Family Studies. Brad's a fascinating writer. And so, where should people go? They want to keep up to date with all of the work that you're doing.

So ifs is a great place to look for a lot of the population work. If you want all my truly unfiltered opinions on this stuff, you can follow me on Twitter. I'm Stone Ky, and you can get all my opinions there on all the sorts of topics that sometimes I should actually shut up up about.

Hell, yeah. Lyman, I appreciate you. Thank you, man.

Good talking. Death away.

Death.