[vidarh]

Sub-Saharan Africa is the only part of the world where the fertility rate is still over replacement (~2.1 children per woman), and it's rapidly dropping there too. The first African country has dropped below replacement (Mauritius), with 10 more (of 55) having dropped below 3 already as of 2020.

China is seeing a population decline not caused by famine for the first time in modern history.

India's fertility rate is at or below replacement at this point, and India is a couple of decades from population contraction unless they increase immigration.

Having 3 children at a young age is an outlier in the vast majority of the world at this point.

[somenameforme]

Scroll down the World Bank's fertility numbers on this page [1] to get to data by region. You can add the entire Arab World, Middle East, North Africa, and South Asia as having sustainable fertility rates. And places like Latin America are in decline, but still in the realm of realm of being saved at ~1.9. The only places currently in catastrophic collapse at the EU (1.5), North America (1.6), and East Asia (1.5).

For those who don't understand why 1.5 is so much worse than 1.9, it's because fertility is an exponential system. Every generation's (~20 years) size is (fertility_rate / 2) times as large as the one prior that gave birth to them. So after 5 generations (~1 century), a fertility rate of 1.9 would see the next generation's size go from 100 to 77 (100 * (1.9/2)^5). A fertility rate of 1.5 would go from 100 to 23. South Korea, at 0.78, would go from 100 to 0 - extinct, in a century.

And most people, across the world, do have children at what you'd call "young" ages. Female fertility rates start to decline rapidly as they age, obviously hitting zero at menopause which tends to happen in their 40s. Even when successful, an older parent results faces exponentially increased odds of seeing a variety of issues with the child, such as Down Syndrome.

[1] - https://en.wikipedia.org/wiki/List_of_countries_by_total_fer...

[vidarh]

> Scroll down the World Bank's fertility numbers on this page [1] to get to data by region. You can add the entire Arab World, Middle East, North Africa, and South Asia as having sustainable fertility rates.

You can use metrics from different groups and slice and dice sections and find ways of getting above 2.1 (replacement), sure, but it's not affecting my main point at all, which was that it's not contained to the Western world, and that 3 kids is now an outlier in most of the world.

To your specifics:

South Asia is listed as 2.2. But India has hit 2.1 and is declining, and Bangladesh and Nepal are even further below replacement - the World Bank metric is I presume buoyed by Pakistan, which has hit 3.1 (3.47 in the 2021 numbers on Wiipedia), and is declining, and Afghanistan, which is in even steeper decline - the other countries in the region are mostly rounding errors in terms of population.

It's a difference of whether it's already hit replacement as a region already, or will within 2-3 years at most. I'm perfectly happy to accept the World Bank numbers for the sake of this argument, as it's not relevant to the argument.

With respect to MENA and the Arab World, you're double-counting. The bulk of the countries that are part of the Arab World vs Middle East /North Africa are the same.

The largest non-Arab MENA countries are Iran, which is well below replacement (1.7) and Turkey, at 1.9.

The Arab World also includes several countries considered sub-Sarahan by some or all of other groups (Somalia, Mauritania, Sudan) which pulls it up, and MENA curiously includes Sudan in some statistics, even though it's considered sub-Saharan and/or East Africa by other groupings.

Once you actually exclude the sub-Saharan countries from those groups, the rate lowers significantly. Taking Sudan alone out of MENA brings MENA close to replacement. If you choose to look at the Arab World alone, then, sure, even excluding the sub-Saharan countries they're still above replacement. I'm again, fine with choosing to slice the numbers that way - they do not affect the argument I was making in any meaningful way, because then the remaining MENA countries are below instead.

What we're left with no matter how we slice it, is that roughly half the worlds countries are below replacement, accounting for well above half the worlds current population (but that balance will shift rapidly), and leaving the world average at ~2.3 and declining even by World Bank numbers.

> And places like Latin America are in decline, but still in the realm of realm of being saved at ~1.9.

There's no "being saved" here. Short of economic collapse, we don't know of any reliable measure to drive these numbers back up again, and they've been consistently trending down since the 1960's. China appears to be poised to be the country likely go hardest in trying, now recommending 3 children per family, and given an extremely restrictive immigration policy. That's fine - they don't need to be "saved".

> The only places currently in catastrophic collapse at the EU (1.5), North America (1.6), and East Asia (1.5).

I was not, and is not, and will not be, arguing any "catastrophic collapse" - to me at least that notion is meaningless to most people other than "great replacement" type people.

The world as a whole is headed for a relatively gentle flattening of population growth, and a period of decline, but no "catastrophic collapse" in population. But we are headed for a fairly dramatic shift in politics and economic development as this happens and the countries facing the steepest drops become more dependent on actually courting immigration as a consequence. There will still be enough growth to do that for decades to come.

[somenameforme]

> "The world as a whole is headed for a relatively gentle flattening of population growth"

You know something that's really weird to think about? In 1950 Africa's population was 227m! [1] The US at the time had about 160m, nearly as many people as the entire African continent! Fertility rates are hard to intuit because they're not only exponential, but systems where the effect is delayed from the cause by several decades, but then once it starts - it starts rocketing off uncontrollably, be that in loss or gain of population.

The world's population may start to level off at some point, but sub-replacement rates will cause Western nations to start losing population at an exponential rate. It will be the equal but opposite of what happened to Africa over the past century. And this doesn't level out or even slow down, except when people start having children again. So for instance many people know Japan now has > 10% of its population over 80, but I think a lot of us have this sort of concept that 'Well sure, but as they start to die off - then things will probably start to look a bit more sane.'

In reality, it's the exact opposite. As this group dies off, they're going to be replaced by an even larger group of 80+ year olds, leaving Japan in an even worse state, as one can immediately see just glancing at Japan's population pyramid. [2] Right now Japan's losing about 1 in 200 people per year, and this will never stop until either they go extinct or they start having children again. And it will actually get substantially worse until they hit their 'fertility equilibrium point' where all living generations have/had comparable fertility rates (picture the sides of the population pyramid having a constant slope). And that's what's waiting for the entirety of the Western world, if we don't turn things around.

And this is also likely a vicious cycle because as age ratios and demographics get all screwed up, economies will start to collapse, which will make it even more uncomfortable to have children.

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[1] - https://www.worldometers.info/world-population/africa-popula...

[2] - https://en.wikipedia.org/wiki/Demographics_of_Japan#/media/F...

[vidarh]

Fertility rates do indeed have that effect, but it's buffeted most places by immigration that will continue to soften the effect for decades to come, so I think it'll be hard to predict how that exactly will play out.

We can already see some differences quite starkly.

E.g. Italy's fertility rate hasn't been above replacement since ca. 1975, and started seeing population decline a few years ago and is already back at the population level it was at around 2007, because it struggles to attract (and want to attract) enough immigration.

Meanwhile, the UK dropped below replacement in 1972, and yet UN projections suggest the population is unlikely to decline until the 2050's at the earliest, and isn't projected to drop down to present-day levels at any point this century, largely buffeted by a far more aggressive immigration policy (including by politicians claiming to want the opposite - neither of the major party in the UK believes in reducing immigration, but some of their voters do, and that is likely to become a rising conflict).

So while I agree some nations probably will see rapid falls, it really comes down to in part to what extent they are able to open their doors and find means of becoming attractive to immigrants fast enough while finding ways of integrating them in a working way.

And this will reshape the political and cultural landscapes both within countries, and international influence.

(one minor example, since we've discussed the UK and Africa: The UK is likely to soon drop from the 2nd to 3rd largest native English-speaking population worldwide - both India and Nigeria already have far more people speaking English as their 2nd or 3rd language, but Nigeria seems to be more rapidly closing the gap to have more people who speak English as their 1st...)

> And this is also likely a vicious cycle because as age ratios and demographics get all screwed up, economies will start to collapse, which will make it even more uncomfortable to have children.

Well, we may unfortunately in that case get to test whether fertility is inexorably linked to poverty or whether once it's declined it won't rise again.

The other option is that as fertility becomes even more of an issue, we'll see a significant escalation in measures like the Hungarian (ramping up grants and subsidised house loans for families that get more children), but of course we don't yet know whether - or at what level - that will work... But I suspect many desperate attempts.

Also, expect reproductive rights to become an issue, with more countries seeming movements to push back on abortion rights etc. using fertility rates as a reason.

[somenameforme]

Earlier you expressed skepticism about the ability of nations to carry out actions to get their fertility numbers back up. And I agree with you. There's quite a lot of evidence, historical and present, that it's really not so easy. And especially for nations that only act once a problem becomes catastrophic, or politically convenient, we'll probably be well into a death spiral before we start acting. So the most probable outcomes aren't looking very hot.

But I'd say here that you're not carrying forward that same reasoned skepticism when offering immigration as a solution. Because the exact same holds true. There are countless examples of mass migration throughout history, and they generally don't come with a happy ending. Rome, over the centuries, became an empire of immigrants, in some ways akin to the United States. Yet it was also ultimately destroyed by immigration. The Goths, fleeing the Huns, were take in as refugees by the Roman Empire. Those same refugees would ultimately go on to destroy the Roman Empire.

In the present day, mass migration doesn't seem to be fairing much better. Prior to the migrant crisis throughout Europe, many expected that the migrants would integrate, become part of the normal mass of people, and it'd ultimately be a win-win situation for everybody. That belief was not well supported by history, and ultimately proved to be false. And in the US today, cities that express an extremely positive attitude towards immigration tend to rapidly express a different view once faced with large numbers of immigrants.

And immigration on the scale we're talking about would be absolutely massive, and never-ending. And I'm not even getting into the countless social/cultural/political problems this would all entail. I'm merely focusing on the most extreme - would this destroy the countries engaging in such? And it seems to me that the most probable answer is simply yes. Well actually in modern times I don't think it'd destroy them. The most likely outcome is what we're seeing happen in much of Europe - parties that oppose the immigration would rapidly come to power, and end up working to mitigate the damage, and end such a population strategy.

[vidarh]

The destruction of the Roman Empire isn't something I lament, and yet if present nation-states survive as long as the Roman Empire they will have done exceptionally well. At the same time I don't buy the narrative. It's a bizarre thing to compare modern migration with fleeing armed groups seeking conquest to replace the places they were fleeing.

It's like comparing the average migrant or refugee with ISIS.

> Prior to the migrant crisis throughout Europe, many expected that the migrants would integrate, become part of the normal mass of people, and it'd ultimately be a win-win situation for everybody. That belief was not well supported by history, and ultimately proved to be false.

I've seen nothing to "prove it false", but there's also a very significant difference a rushed an chaotic acceptance of refugees vs. planned migration programs, and either takes time to shake out.

> And in the US today, cities that express an extremely positive attitude towards immigration tend to rapidly express a different view once faced with large numbers of immigrants.

And yet the US managed to successfully do it before. Several of my own ancestors families lived in Brooklyn at a time where it was so full of Scandinavian migrants that it had several Norwegian language newspapers, and my great grandmother lived there a decade without ever learning English because all her neighbours and shopkeepers etc. spoke Norwegian. I've spent a lot of time looking at US censuses because for the sake of genealogy, and the US censuses of that era are astounding for the way whole streets were nothing but immigrants.

Somehow the US is still there, as much as one might joke about the state it is in.

> The most likely outcome is what we're seeing happen in much of Europe - parties that oppose the immigration would rapidly come to power, and end up working to mitigate the damage, and end such a population strategy.

Then they will crater their economies, and soon enough get thrown out of office. People are quick to support anti-immigran rhetoric until it starts hitting their wallet when eg. employers struggle to hire. These anti-immigration parties fortunes tends to be tightly linked to unemployment levels.

Compare Italy to e.g. the UK, where despite the anti refugee rhetoric and historically high immigration, people fleeing the Tory party are not going to the anti-immigrant right-wing parties but to Labour - the UK, unlike Italy, has low unemployment and regular newspaper stories about employers struggling to find workers. Once Italy's population decline bites a bit more, this will change rapidly.

[Rapzid]

South Korea has entered the chat..

Seriously, it's wild visiting South Korea and having a tour guide jokingly beg people to immigrate and make babies.

#JokingNotJoking

[vidarh]

Part of this is that South Korea was practically closed to immigration until around 2004 outside of the "usual" workarounds (marrying a local, or significant investment), and so it's become increasingly urgent.

They've liberalised a lot since, but it'll take a long time for them to develop a reputation as somewhere people will think of as a destination to migrate to.