Many, including my colleague Bryan Caplan, are confident that the widely forecasted world population fall based on fertility trends won’t last long, because: selection.
In the 2019 article that you cite here, we make the point that heritability needs to be taken into account in future population projections. UN predictions are based on the built-in assumption that fertility will move below replacement level and, therefore, that global population will decline. We made the point that the heritability of fertility should be taken into account as a force acting against this decline. Your question about whether fertility will rebound above replacement level or not as a consequence is fair. More research should be conducted on the interplay between the cultural dynamics that may nudge fertility downward and the mechanical effect of the heritability of fertility that pushes in the other direction.
Note that the key challenge for cultural explanations of long term decline is to explain how cultural dynamics can counteract the cumulative effect of heritability of fertility over time. Your argument about past episodes of decline is, in that light, interesting.
I don't have access to your paper. Has anyone tried to estimate the genetic heritability (or not) of a psychological tendency toward high fertility? (Phrasing this way to distinguish from physical causes of infertility such as ovulation problems, low sperm count, etc.) It seems to me this is the wild card in this whole question of population.
Historically a mere enjoyment of sex was enough to ensure that children appeared. That has changed, which brings to the forefront whatever traits might make a person want kids directly. Any such traits (if they exist and are genetically heritable) will be very strongly selected for in the future.
The 2019 paper is interesting, including the many references to studies investigating eventual heritability using historical data.
Concerning cultural-social-political facors that may contribute to reverse the fertility trend, I have tended to relate that to Esping-Andersen & Billari's hypothesis that politicians will sooner or later introduce pro-natalist policies sufficient to reverse the trend. (Population and Development Review 41(1), 1-31 March 2015.) They base this prediction on the empirical observation that when people across high-income countries are asked which fertility level they would personally prefer, the average is above 2.1 almost everywhere (while at the same time actual fertility is below 2.1. everywhere). Implying that there is longer-term vote gain to be had by promoting pronatalist policies. (Alternatively: rulers who do not strengthen such policies are gradually weeded out of office.)
So far, data does not suggest that this effect is strong enough to bring levels back above 2.1 anywhere - since levels are below 2.1 even in the countries that most ardently push pronatalist policies. But the Esping-Andersen/Billari hypothesis is still worth keeping in the back of one's head, as a possible mechanism that might reverse the trend.
The concern might be that the response sensitivity might be higher for those cultures that are already enjoying high fertility. We probably want declining marginal benefits.
So far, no. We agree there. The effect has been limited.
So far, only the first part of the prediction holds out: Pronatalist policies are indeed becoming more widespread in high-income countries. Good data here. (Often under the label family-friendly policies, but it boils down to the same thing.)
It remains to be seen if such policies might have an effect in a longer time perspective. Or, alternatively, if the lack of effect will push rulers to introduce even more dramatic pronatalist policy measures, until an effect eventually materializes.
>I find it suspicious that though we didn’t see such selection effects over the many centuries decline of the Ancient Greek and Roman empires, nor in other ancient empires, nor over the last few centuries of declining fertility, we are just now about to see it kick in strong enough to reverse fertility decline.
Presumably we're in a novel situation in that propensity to make babies is more or less the ONLY psychological characteristic that nature is selecting for in humans at this moment in time. Providing food and shelter for an unlimited number of children is -- uniquely in history -- trivial for us now; if the parents can't do it, the state will.
In the past, many of the personality traits that caused someone to make the largest possible number of babies were negatively correlated to their children's survival. And in a world where most children do NOT survive long enough to reproduce, propensity to keep one's kids alive was frequently more important than the propensity to reproduce maximally. This is no longer the case; those same qualities that caused our ancestors to sensibly worry about having another mouth to feed in the face of an uncertain harvest are, under conditions of modernity, causing many to worry about having any children at all.
The problem is that it's the common interest of many memes to sterilize their human hosts and then use the newly-liberated reproductive resources for meme spreading - preaching, teaching, etc. Cultural evolution is generally much faster than the evolution of human DNA genes. So: I'm pretty sceptical about the population bouncing back due to the Amish or Islam or whatever.
I think the argument is that the Amish would be immune to the low-fertility memes because they have other memes that are incompatible with the low-fertility memes. The low fertility memes would not be able to infect the Amish.
The Amish population is less than 0.1% of the US population. However many kids they are having, it doesn't look as though that many of them stay Amish - so I am sceptical about whether their memetic immune system is all that good at rejecting non-Amish memes over multiple generations. Islam may be a bit of a different story.
Most who are raised Amish stay Amish. Why don’t you just look it up before assuming things? The number of children they have who stay Amish is much higher than the number of children mainstream people are having. They are doubling their population every 22 years.
Sorry - thanks for the correction. Am still having a hard time picturing old time religions winning against the industrial complex due to human fertility. I think it is not going to happen.
There is an interesting book about this. I find it compelling. You can find talks about it if you don’t want to listen to the whole book. Shall the Religious Inherit the Earth?: Demography and Politics in the Twenty-first Century https://a.co/d/hYG4C6v
Thanks. The whole argument seems based on only counting human heads. Whereas the actual competition for resources also involves machines and robots. Primitive superstitions seem unlikely to me to win out against the whole train of technology and progress. I don't know exactly how it will go down - but I know which side to bet on.
ChatGPT 4o: Adaptive refers to the ability or tendency of an organism, system, or process to adjust and modify itself to changing conditions or environments. It involves being flexible, responsive, and capable of evolving or transforming in response to new challenges, opportunities, or information. In a broader sense, adaptive characteristics enable better survival, efficiency, or effectiveness in dynamic and varied situations.
What does fertility inheritability have to do with abortion?
In the US, the ratio of reported abortions to live births was 1 to 3 every year from 1973 to 1998, based on numbers from the CDC.
That's a 25% kill rate, we killed a quarter of a generation in the womb.
~1998 - chemically induced abortion was introduced.
~2000- Plan B was introduced.
The ratio in 2020, again based on numbers from the CDC, was 1 reported abortion to every 5 live births.
That's a 16.7% kill rate, but some areas no longer report abortions but do report births, it doesn't account for Plan B and some chemically induced abortions. So, we know the actual kill rate is definitely higher than 16.7%
Our fertility problem is that we no longer value human life, we don't just deem it worthless, we hold it as a negative value, a burden to be extinguished at one's convenience.
Uh.... cross-cultural researcher here. Regarding "Here are some cultural dimensions where the world will likely get worse."
The list you provide is a list of the major dimensions of cross-cultural variations noted by researchers, beginning with Hofstede's well-known dimensions of cultural variation. Most of these dimensions have advantages and disadvantages. These dimensions were formulated by experts because there is not supposed to be a worse pole. Cultures evolve a specific place (or range) on the dimension to solve the unique problems facing that culture, as defined by its subsistence method, ecology and history of cultural practices (all three of these subsume technology).
So, the world can not get 'worse' at these cultural dimensions without specifying which pole you feel is worse (and that needs to be substantiated) and the conditions (the three variables listed above) which are the reason why one pole is worse than the other. Because cultural practices develop to solve fitness-related (survivability) problems (including signaling status, reputation, etc).
By worse you may mean "not the type of culture where I prefer to embed." But that is independent of terms like better/worse.
But... I don't want to alienate you, Prof. Hanson. I'm still reading The Elephant in the Brain and find it one of the best books I've read in a long time.
By "worse" I just mean less adaptive. Yes, these dimensions were designed to be ones where we could less say which direction is good. But in each context, I'm confident there are in fact better directions, but that cultural drift means we'll have mostly random change, moving on net away from whatever is adaptively optimal.
The test by which cultures can be ranked as better or worse is in their ability to produce preferred outcomes for members. Survival tends to be preferred over extinction, so any culture that produces lower rates survival for its members is worse. Material welfare tends to be preferred over poverty so any culture that produces poverty for many of its members is worse. A meaningful life tends to be preferred to one devoid of meaning, so any culture that fails to produce a sense of meaning for many members is worse.
But all extant cultures have survived, so we can't use survival to measure the value of cultural attributes in extant cultures. Once cultures have gone extinct one can analyze their norms, values and behaviors, as Jarad Diamond did in his book Collapse. In examining extant cultures, one sees a variety of cultural patterns operating to enhance survival, because different problems need to be solved depending on the ecosystem. People who are living under slavery need to have different values from those who ended up in a position where they can exploit slaves. The values that enhance fitness in one culture may depress it in another.
I think we can do some extrapolation rather than waiting until each culture has gone extinct. Shakers, for example, aren't completely gone, but I think we can go ahead and say that they will be.
It is only future survival that matters and it can be predicted, indeed it must. Also, I was referring to member survival rates, not culture survival probability. Of course, you can’t do science around predictions alone.
...if we investigate changes in "boring" outcome-indicators like the Human Development Index (HDI), under-five mortality and population-adjusted GDP per capita (in particular in total life-cycle GDP per capita), the long-term global trends are still toward improvements.
True. On the other hand, the rapid fertility decline in East Asia is a major reason why GDP per capita (and likely also HDI) has risen so fast in this part of the world.
(..and the lack of a similar rapid fertility decline in Sub-Saharan Africa is a major reason for the less impressive GDP per capita rise in this part of the world.)
All the more reason to think that without fertility in your measure of welfare you will see systemic measurement biases arising from the redistribution of resources over a smaller population.
To call it "bias" is a rather strange way to frame this change, since there are cause-effect relationships between fewer children and GDP per capita growth. (In addition to the obvious point that when fewer family members share the same household income, this increases household income per capita.)
Examples of cause-effect relationship: Fewer children per family makes it more manageable for parents to invest in their children, leading to better nutrition, better health and a rise in education levels, which in due time creates a healthier and more efficient labor force, plus a better utilisation of the comparative advantages of each child. And so on.
...sort-of moving from an r towards a K reproduction strategy, if you want to give the argument an evolutionary twist.
You won't admit it, but here you have finally discovered the existence of the Great Replacement and of the fact that it is problematic, in some ways at least. Like it or not, fundamentalist religious views such as the Muslims do cause their followers to both reproduce more reliably and often, and to preserve and spread their religious beliefs, than either "wokism" or modern Christianity; thus we either have to learn to live with cultural replacement, or to impart and the same evolutionary strengths through our own belief-communities before it is too late.
I don't see us winning this race, but I don't expect "wokism" to win it either. The future is most likely either Islamic or Chinese, at least for the next two or three centuries.
The consensus is that Africa will become a much larger fraction of world population over the next 50 years. Just because they'll have higher fertility. I'm less concerned now about relative fractions than about the total numbers.
The chinese birthrates are now among the worst in the world, so the future is definitely not chinese.
Also, birthrates are falling across the islamic world too. They are still high because of how recently the islamic world has urbanized, because its urbanization, fundamentally, which has precipitated declines in birthrates everywhere that theyve happened.
The great replacement, in the form that most people use that term, just isnt nusnced enough. People who have kids will replace those who dont, everywhere at once.
Europe will fall further than the middle east because it is more urbanized, just like east asia will, in turn, collapse even more than europe for the same reason. But europe (and the US) also has things going for it that other places dont, like good land and climate, which can support a relatively high standard of living from few inputs, and a rural population which is culturally and politically at odds with the urbanites, rather than culturally homogeneous with them.
The problem with most of the islamic world is that most of it is in geography that has never supported large populations until they could start importing fertilizer and electricity, so if anything goes wrong for them, they have very little, if anything, to fall back on. And due to rapid urbanization, which occuring in the social media era, their rural population is more culturally integrated with the urban population, and may be more susceptible to value shift from the urbanites than the rural populations in the West have been.
"...a rural population which is culturally and politically at odds with the urbanites, rather than culturally homogeneous with them."
If you refer to fertility, the data I have seen suggests that this is a leaders-laggards development sequence, not stable urban-rural differences.
At least in the European countries where I have seen data, the differences in fertility between urban and rural areas were much larger in earlier decades. They have practically disappeared in many countries by now.
If you know of data across time that show stable fertility differences across the urban-rural divide in the US or anywhere else, I would be very interested in the references (since I collect material for a book related to these issues).
Pentecostalism is very strong in sub-Saharan Africa. Pentecostalism is under the radar for many, but in absolute numbers it is the fastest-growing religion in the history of mankind.
Pentecostalism is going to be massively strengthened in the next century due to sub-Saharan Africa being just about the only place left with high birth rates. In comparison, the much more Muslim-dominated countries in the Middle East have experienced steep fertility declines the last decades. Iran has long been under 2.1 children per woman. Turkey is also there now, and the others are closing in fast (if we can trust national statistics).
Whilst any dates for a turnaround are highly speculative, the key message for people to take away is that there is that two particular outcomes that are widely believed are almost certainly impossible:
1) That the human population will stabilise at some number that is "in harmony with the planet".
2) That the human population will reduce to 0 due to declining birth rates.
With regard to 1, there is just no proposed mechanism, other than totalitarian control, that could make this happen.
With regards to 2, Culture cannot achieve this because the required culture will inevitably break down long before the population falls to critical levels - Our culture is dependent on the existence of, at least millions, if not billions of people.
In terms of us not seeing fertility heritability effects in past declines: I don't find this all that suspicious. In the past, 1) there was already much higher non-cultural selection pressure favoring biological factors affecting fertility, since there needed to be many more babies even to maintain (let alone grow) population, so variation in these factors probably got wiped out faster, and 2) fertility was much less of a choice before the advent of modern birth control. If you got married, and you were able to have kids, then you were going to end up with kids. This is even more true when you think about, as one example, how it was only in the late 1970s that the US began to recognize that marital rape was a thing. In the past, there would have been much less room for effects from the heritable *psychological* factors that today affect fertility.
I don't think this changes your conclusion significantly, though.
"I find it suspicious that though we didn’t see such selection effects over the many centuries decline of the Ancient Greek and Roman empires, nor in other ancient empires"
What are you talking about here? Ancient empires were generally either at their Malthusian limits or growing towards them, not held back by fertility rates.
Ah just as I thought - Roman elites did indeed have a bit of a moral panic at times about their own fertility, but there was never any indication that the Roman Empire's population as a whole ever declined due to low fertility. That's even the conclusion of the Rome-related article you link to in that post:
>Classical literary sources, tombstone inscriptions and skeletal remains have been used by classicists to show that there was probably a decline in the population of the Roman Empire caused by the deliberate control of family numbers through contraception, infanticide and child exposure. This finding is important as it appears to demonstrate that the fertility transition associated with the modern Industrial Revolution is not unique and may have had predecessors. Although few new classical demographic data have become available, there has been a vast increase in interest in classical demography, reflecting the late twentieth-century focus on population change, especially fertility control, and the associated development of demographic analytical techniques and models. This new classical demography has largely strengthened previous findings on mortality and marriage, but it has suggested that the Roman Empire's population was near-stationary, rather than declining, and exhibited natural fertility. Nevertheless, the literary tradition may be correct in suggesting that the elite faced great problems in preventing the family patrimony from being dispersed by partible inheritance and so resorted to restricting their legitimate family size, largely by child exposure. The parallel may not be the modern fertility transition but the lower sectional fertility achieved by the bourgeoisie of Geneva in the eighteenth century.
ChatGPT: The Romans used a variety of plants and herbal concoctions believed to have contraceptive properties. One of the most famous was Silphium, a plant that was so highly valued for its supposed contraceptive effects that it was harvested to extinction.
What about it? We definitely know that at least some segments of the Roman population practiced a variety of forms of contraception, it's just that we also know they didn't end up with a lower overall population because of it.
By the way, is the implication of the "ChatGPT" at the start of your comment that you got your information about silphium from ChatGPT? Please don't use LLMs as an information source, or at least make sure to go find a real source for anything they give you.
"What about it?" I just thought you might appreciate a piece of the puzzle that you seemed to be missing. The view of the Romans as using child exposure as their main form of family size control may be gravely mistaken.
"you got your information about silphium from ChatGPT?" Not really. I knew there was a herbal contraception that went extinct, but didn't recall its name. I then verified the name against Wikipedia. At any rate, I can't see why you would trust me more than ChatGPT. I'm just an internet rando to you, and you still need to verify for yourself everything.
In what sense was I missing that piece of the puzzle? My own post already mentioned contraception as one of the methods of Roman era family planning.
It's not that I trust you more than ChatGPT, it's that ChatGPT is not a source you should be citing to me. It's like if instead of "ChatGPT" you wrote "My friend Bob says"
Low fertility will increase the dependency ratio and mean a larger portion of voters are dependent. Taxes will be raised on fertility age producers who will respond by having fewer children to maintain their living standards. This will cycle upon itself and just get worse and worse.
"...we should expect to see a continued decline in the quality of our cultural norms, values, and status markers."
Well, but on the other hand, if we investigate changes in "boring" outcome-indicators like the Human Development Index (HDI), under-five mortality and population-adjusted GDP per capita (in particular in total life-cycle GDP per capita), the long-term global trends are still toward improvements. (Plus converging outcomes between the West and the Rest.)
Admittedly, it may be a case of what Bertrand Russell labelled "the turkey's illusion". No improvement can go on forever. The fall may be hard and fast. But so far, qua turkeys, we observe global improvements.
In the 2019 article that you cite here, we make the point that heritability needs to be taken into account in future population projections. UN predictions are based on the built-in assumption that fertility will move below replacement level and, therefore, that global population will decline. We made the point that the heritability of fertility should be taken into account as a force acting against this decline. Your question about whether fertility will rebound above replacement level or not as a consequence is fair. More research should be conducted on the interplay between the cultural dynamics that may nudge fertility downward and the mechanical effect of the heritability of fertility that pushes in the other direction.
Note that the key challenge for cultural explanations of long term decline is to explain how cultural dynamics can counteract the cumulative effect of heritability of fertility over time. Your argument about past episodes of decline is, in that light, interesting.
I don't have access to your paper. Has anyone tried to estimate the genetic heritability (or not) of a psychological tendency toward high fertility? (Phrasing this way to distinguish from physical causes of infertility such as ovulation problems, low sperm count, etc.) It seems to me this is the wild card in this whole question of population.
Historically a mere enjoyment of sex was enough to ensure that children appeared. That has changed, which brings to the forefront whatever traits might make a person want kids directly. Any such traits (if they exist and are genetically heritable) will be very strongly selected for in the future.
The 2019 paper is interesting, including the many references to studies investigating eventual heritability using historical data.
Concerning cultural-social-political facors that may contribute to reverse the fertility trend, I have tended to relate that to Esping-Andersen & Billari's hypothesis that politicians will sooner or later introduce pro-natalist policies sufficient to reverse the trend. (Population and Development Review 41(1), 1-31 March 2015.) They base this prediction on the empirical observation that when people across high-income countries are asked which fertility level they would personally prefer, the average is above 2.1 almost everywhere (while at the same time actual fertility is below 2.1. everywhere). Implying that there is longer-term vote gain to be had by promoting pronatalist policies. (Alternatively: rulers who do not strengthen such policies are gradually weeded out of office.)
So far, data does not suggest that this effect is strong enough to bring levels back above 2.1 anywhere - since levels are below 2.1 even in the countries that most ardently push pronatalist policies. But the Esping-Andersen/Billari hypothesis is still worth keeping in the back of one's head, as a possible mechanism that might reverse the trend.
I see. My impression, though, is that there is not much evidence that pro-natalist policies have a significant effect.
We economists are confident that there is a high enough price to have a substantial effect.
As an economist, I share this view. The amounts usually involved in pro-natalist policies seem relatively small.
The concern might be that the response sensitivity might be higher for those cultures that are already enjoying high fertility. We probably want declining marginal benefits.
So far, no. We agree there. The effect has been limited.
So far, only the first part of the prediction holds out: Pronatalist policies are indeed becoming more widespread in high-income countries. Good data here. (Often under the label family-friendly policies, but it boils down to the same thing.)
It remains to be seen if such policies might have an effect in a longer time perspective. Or, alternatively, if the lack of effect will push rulers to introduce even more dramatic pronatalist policy measures, until an effect eventually materializes.
An important element of fixing fertility falls: https://ishayirashashem.substack.com/p/look-at-cute-babies
>I find it suspicious that though we didn’t see such selection effects over the many centuries decline of the Ancient Greek and Roman empires, nor in other ancient empires, nor over the last few centuries of declining fertility, we are just now about to see it kick in strong enough to reverse fertility decline.
Presumably we're in a novel situation in that propensity to make babies is more or less the ONLY psychological characteristic that nature is selecting for in humans at this moment in time. Providing food and shelter for an unlimited number of children is -- uniquely in history -- trivial for us now; if the parents can't do it, the state will.
In the past, many of the personality traits that caused someone to make the largest possible number of babies were negatively correlated to their children's survival. And in a world where most children do NOT survive long enough to reproduce, propensity to keep one's kids alive was frequently more important than the propensity to reproduce maximally. This is no longer the case; those same qualities that caused our ancestors to sensibly worry about having another mouth to feed in the face of an uncertain harvest are, under conditions of modernity, causing many to worry about having any children at all.
The problem is that it's the common interest of many memes to sterilize their human hosts and then use the newly-liberated reproductive resources for meme spreading - preaching, teaching, etc. Cultural evolution is generally much faster than the evolution of human DNA genes. So: I'm pretty sceptical about the population bouncing back due to the Amish or Islam or whatever.
I think the argument is that the Amish would be immune to the low-fertility memes because they have other memes that are incompatible with the low-fertility memes. The low fertility memes would not be able to infect the Amish.
The Amish population is less than 0.1% of the US population. However many kids they are having, it doesn't look as though that many of them stay Amish - so I am sceptical about whether their memetic immune system is all that good at rejecting non-Amish memes over multiple generations. Islam may be a bit of a different story.
They Amish have a 93% retention rate; almost all of them stay Amish.
Most who are raised Amish stay Amish. Why don’t you just look it up before assuming things? The number of children they have who stay Amish is much higher than the number of children mainstream people are having. They are doubling their population every 22 years.
Sorry - thanks for the correction. Am still having a hard time picturing old time religions winning against the industrial complex due to human fertility. I think it is not going to happen.
There is an interesting book about this. I find it compelling. You can find talks about it if you don’t want to listen to the whole book. Shall the Religious Inherit the Earth?: Demography and Politics in the Twenty-first Century https://a.co/d/hYG4C6v
Thanks. The whole argument seems based on only counting human heads. Whereas the actual competition for resources also involves machines and robots. Primitive superstitions seem unlikely to me to win out against the whole train of technology and progress. I don't know exactly how it will go down - but I know which side to bet on.
When you say these cultural dimensions will get worse, what does worse mean?
Less adaptive.
Less adaptive == less chance of survival?
"adaptive" is a widely used concept; I don't need to define it anew.
ChatGPT 4o: Adaptive refers to the ability or tendency of an organism, system, or process to adjust and modify itself to changing conditions or environments. It involves being flexible, responsive, and capable of evolving or transforming in response to new challenges, opportunities, or information. In a broader sense, adaptive characteristics enable better survival, efficiency, or effectiveness in dynamic and varied situations.
Me: this ChatGPT is such a smart ass.
I've written an FAQs page explaining why declining fertility won't last long: https://zerocontradictions.net/FAQs/overpopulation-FAQs.
What does fertility inheritability have to do with abortion?
In the US, the ratio of reported abortions to live births was 1 to 3 every year from 1973 to 1998, based on numbers from the CDC.
That's a 25% kill rate, we killed a quarter of a generation in the womb.
~1998 - chemically induced abortion was introduced.
~2000- Plan B was introduced.
The ratio in 2020, again based on numbers from the CDC, was 1 reported abortion to every 5 live births.
That's a 16.7% kill rate, but some areas no longer report abortions but do report births, it doesn't account for Plan B and some chemically induced abortions. So, we know the actual kill rate is definitely higher than 16.7%
Our fertility problem is that we no longer value human life, we don't just deem it worthless, we hold it as a negative value, a burden to be extinguished at one's convenience.
At look at all these unfertilized eggs too. So much potential! (I'm being sarcastic)
Uh.... cross-cultural researcher here. Regarding "Here are some cultural dimensions where the world will likely get worse."
The list you provide is a list of the major dimensions of cross-cultural variations noted by researchers, beginning with Hofstede's well-known dimensions of cultural variation. Most of these dimensions have advantages and disadvantages. These dimensions were formulated by experts because there is not supposed to be a worse pole. Cultures evolve a specific place (or range) on the dimension to solve the unique problems facing that culture, as defined by its subsistence method, ecology and history of cultural practices (all three of these subsume technology).
So, the world can not get 'worse' at these cultural dimensions without specifying which pole you feel is worse (and that needs to be substantiated) and the conditions (the three variables listed above) which are the reason why one pole is worse than the other. Because cultural practices develop to solve fitness-related (survivability) problems (including signaling status, reputation, etc).
By worse you may mean "not the type of culture where I prefer to embed." But that is independent of terms like better/worse.
But... I don't want to alienate you, Prof. Hanson. I'm still reading The Elephant in the Brain and find it one of the best books I've read in a long time.
By "worse" I just mean less adaptive. Yes, these dimensions were designed to be ones where we could less say which direction is good. But in each context, I'm confident there are in fact better directions, but that cultural drift means we'll have mostly random change, moving on net away from whatever is adaptively optimal.
The test by which cultures can be ranked as better or worse is in their ability to produce preferred outcomes for members. Survival tends to be preferred over extinction, so any culture that produces lower rates survival for its members is worse. Material welfare tends to be preferred over poverty so any culture that produces poverty for many of its members is worse. A meaningful life tends to be preferred to one devoid of meaning, so any culture that fails to produce a sense of meaning for many members is worse.
But all extant cultures have survived, so we can't use survival to measure the value of cultural attributes in extant cultures. Once cultures have gone extinct one can analyze their norms, values and behaviors, as Jarad Diamond did in his book Collapse. In examining extant cultures, one sees a variety of cultural patterns operating to enhance survival, because different problems need to be solved depending on the ecosystem. People who are living under slavery need to have different values from those who ended up in a position where they can exploit slaves. The values that enhance fitness in one culture may depress it in another.
I think we can do some extrapolation rather than waiting until each culture has gone extinct. Shakers, for example, aren't completely gone, but I think we can go ahead and say that they will be.
It is only future survival that matters and it can be predicted, indeed it must. Also, I was referring to member survival rates, not culture survival probability. Of course, you can’t do science around predictions alone.
...if we investigate changes in "boring" outcome-indicators like the Human Development Index (HDI), under-five mortality and population-adjusted GDP per capita (in particular in total life-cycle GDP per capita), the long-term global trends are still toward improvements.
Good point: They did forgot to put fertility in the HDI.
True. On the other hand, the rapid fertility decline in East Asia is a major reason why GDP per capita (and likely also HDI) has risen so fast in this part of the world.
(..and the lack of a similar rapid fertility decline in Sub-Saharan Africa is a major reason for the less impressive GDP per capita rise in this part of the world.)
All the more reason to think that without fertility in your measure of welfare you will see systemic measurement biases arising from the redistribution of resources over a smaller population.
To call it "bias" is a rather strange way to frame this change, since there are cause-effect relationships between fewer children and GDP per capita growth. (In addition to the obvious point that when fewer family members share the same household income, this increases household income per capita.)
Examples of cause-effect relationship: Fewer children per family makes it more manageable for parents to invest in their children, leading to better nutrition, better health and a rise in education levels, which in due time creates a healthier and more efficient labor force, plus a better utilisation of the comparative advantages of each child. And so on.
...sort-of moving from an r towards a K reproduction strategy, if you want to give the argument an evolutionary twist.
You won't admit it, but here you have finally discovered the existence of the Great Replacement and of the fact that it is problematic, in some ways at least. Like it or not, fundamentalist religious views such as the Muslims do cause their followers to both reproduce more reliably and often, and to preserve and spread their religious beliefs, than either "wokism" or modern Christianity; thus we either have to learn to live with cultural replacement, or to impart and the same evolutionary strengths through our own belief-communities before it is too late.
I don't see us winning this race, but I don't expect "wokism" to win it either. The future is most likely either Islamic or Chinese, at least for the next two or three centuries.
The consensus is that Africa will become a much larger fraction of world population over the next 50 years. Just because they'll have higher fertility. I'm less concerned now about relative fractions than about the total numbers.
The chinese birthrates are now among the worst in the world, so the future is definitely not chinese.
Also, birthrates are falling across the islamic world too. They are still high because of how recently the islamic world has urbanized, because its urbanization, fundamentally, which has precipitated declines in birthrates everywhere that theyve happened.
The great replacement, in the form that most people use that term, just isnt nusnced enough. People who have kids will replace those who dont, everywhere at once.
Europe will fall further than the middle east because it is more urbanized, just like east asia will, in turn, collapse even more than europe for the same reason. But europe (and the US) also has things going for it that other places dont, like good land and climate, which can support a relatively high standard of living from few inputs, and a rural population which is culturally and politically at odds with the urbanites, rather than culturally homogeneous with them.
The problem with most of the islamic world is that most of it is in geography that has never supported large populations until they could start importing fertilizer and electricity, so if anything goes wrong for them, they have very little, if anything, to fall back on. And due to rapid urbanization, which occuring in the social media era, their rural population is more culturally integrated with the urban population, and may be more susceptible to value shift from the urbanites than the rural populations in the West have been.
Food for thought
"...a rural population which is culturally and politically at odds with the urbanites, rather than culturally homogeneous with them."
If you refer to fertility, the data I have seen suggests that this is a leaders-laggards development sequence, not stable urban-rural differences.
At least in the European countries where I have seen data, the differences in fertility between urban and rural areas were much larger in earlier decades. They have practically disappeared in many countries by now.
If you know of data across time that show stable fertility differences across the urban-rural divide in the US or anywhere else, I would be very interested in the references (since I collect material for a book related to these issues).
Pentecostalism is very strong in sub-Saharan Africa. Pentecostalism is under the radar for many, but in absolute numbers it is the fastest-growing religion in the history of mankind.
Pentecostalism is going to be massively strengthened in the next century due to sub-Saharan Africa being just about the only place left with high birth rates. In comparison, the much more Muslim-dominated countries in the Middle East have experienced steep fertility declines the last decades. Iran has long been under 2.1 children per woman. Turkey is also there now, and the others are closing in fast (if we can trust national statistics).
Whilst any dates for a turnaround are highly speculative, the key message for people to take away is that there is that two particular outcomes that are widely believed are almost certainly impossible:
1) That the human population will stabilise at some number that is "in harmony with the planet".
2) That the human population will reduce to 0 due to declining birth rates.
With regard to 1, there is just no proposed mechanism, other than totalitarian control, that could make this happen.
With regards to 2, Culture cannot achieve this because the required culture will inevitably break down long before the population falls to critical levels - Our culture is dependent on the existence of, at least millions, if not billions of people.
In terms of us not seeing fertility heritability effects in past declines: I don't find this all that suspicious. In the past, 1) there was already much higher non-cultural selection pressure favoring biological factors affecting fertility, since there needed to be many more babies even to maintain (let alone grow) population, so variation in these factors probably got wiped out faster, and 2) fertility was much less of a choice before the advent of modern birth control. If you got married, and you were able to have kids, then you were going to end up with kids. This is even more true when you think about, as one example, how it was only in the late 1970s that the US began to recognize that marital rape was a thing. In the past, there would have been much less room for effects from the heritable *psychological* factors that today affect fertility.
I don't think this changes your conclusion significantly, though.
Does Overcoming Bias have an associated discord server? In case it doesn't I've set up one. Here's the invite link: https://discord.gg/wqSAuw2tx6
"I find it suspicious that though we didn’t see such selection effects over the many centuries decline of the Ancient Greek and Roman empires, nor in other ancient empires"
What are you talking about here? Ancient empires were generally either at their Malthusian limits or growing towards them, not held back by fertility rates.
https://www.overcomingbias.com/p/ancient-fertility-quotes
Ah just as I thought - Roman elites did indeed have a bit of a moral panic at times about their own fertility, but there was never any indication that the Roman Empire's population as a whole ever declined due to low fertility. That's even the conclusion of the Rome-related article you link to in that post:
>Classical literary sources, tombstone inscriptions and skeletal remains have been used by classicists to show that there was probably a decline in the population of the Roman Empire caused by the deliberate control of family numbers through contraception, infanticide and child exposure. This finding is important as it appears to demonstrate that the fertility transition associated with the modern Industrial Revolution is not unique and may have had predecessors. Although few new classical demographic data have become available, there has been a vast increase in interest in classical demography, reflecting the late twentieth-century focus on population change, especially fertility control, and the associated development of demographic analytical techniques and models. This new classical demography has largely strengthened previous findings on mortality and marriage, but it has suggested that the Roman Empire's population was near-stationary, rather than declining, and exhibited natural fertility. Nevertheless, the literary tradition may be correct in suggesting that the elite faced great problems in preventing the family patrimony from being dispersed by partible inheritance and so resorted to restricting their legitimate family size, largely by child exposure. The parallel may not be the modern fertility transition but the lower sectional fertility achieved by the bourgeoisie of Geneva in the eighteenth century.
ChatGPT: The Romans used a variety of plants and herbal concoctions believed to have contraceptive properties. One of the most famous was Silphium, a plant that was so highly valued for its supposed contraceptive effects that it was harvested to extinction.
What about it? We definitely know that at least some segments of the Roman population practiced a variety of forms of contraception, it's just that we also know they didn't end up with a lower overall population because of it.
By the way, is the implication of the "ChatGPT" at the start of your comment that you got your information about silphium from ChatGPT? Please don't use LLMs as an information source, or at least make sure to go find a real source for anything they give you.
"What about it?" I just thought you might appreciate a piece of the puzzle that you seemed to be missing. The view of the Romans as using child exposure as their main form of family size control may be gravely mistaken.
"you got your information about silphium from ChatGPT?" Not really. I knew there was a herbal contraception that went extinct, but didn't recall its name. I then verified the name against Wikipedia. At any rate, I can't see why you would trust me more than ChatGPT. I'm just an internet rando to you, and you still need to verify for yourself everything.
In what sense was I missing that piece of the puzzle? My own post already mentioned contraception as one of the methods of Roman era family planning.
It's not that I trust you more than ChatGPT, it's that ChatGPT is not a source you should be citing to me. It's like if instead of "ChatGPT" you wrote "My friend Bob says"
Low fertility will increase the dependency ratio and mean a larger portion of voters are dependent. Taxes will be raised on fertility age producers who will respond by having fewer children to maintain their living standards. This will cycle upon itself and just get worse and worse.
"...we should expect to see a continued decline in the quality of our cultural norms, values, and status markers."
Well, but on the other hand, if we investigate changes in "boring" outcome-indicators like the Human Development Index (HDI), under-five mortality and population-adjusted GDP per capita (in particular in total life-cycle GDP per capita), the long-term global trends are still toward improvements. (Plus converging outcomes between the West and the Rest.)
Admittedly, it may be a case of what Bertrand Russell labelled "the turkey's illusion". No improvement can go on forever. The fall may be hard and fast. But so far, qua turkeys, we observe global improvements.
Have you looked at all into whether the decline is significantly impacted by some toxin (e.g. environmental, medicinal, etc.)?