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Joy Hughes's avatar

Falling human fertility is a good thing, given Earth's carrying capacity

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Liface's avatar

I don't know how this misconception keeps coming up in every debate about this:

It's not about if it's good or not, it's about how *fast* we get there.

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Nikita Sokolsky's avatar

I’ve never seen an honest attempt to calculate the “Earth carrying capacity” which resulted in less than ~15B humans as the lower limit. Anything lower always relies on absurd mental gymnastics, such as “sorry nuclear won’t work because we’ll have nowhere to bury the radioactive waste” or “we need to tear down all housing in England to give the land back to the wolves and foxes”.

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Joy Hughes's avatar

It really depends on what those humans are doing - the number we have right now times the average consumption has us in overshoot already, and has been catastrophic for wildlife, earth systems, and more. Natural population decline would allow more space for the ecosystem to function and to sustain all life, including humans.

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John's avatar

Sir have you been to Texas? Or North Dakota? Or like anywhere west of the Mississippi and east of the Rockies?

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Joy Hughes's avatar

All particularly dry areas suited to pastoralism with low local carrying capacity.

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Jeffrey Soreff's avatar

nit: Visible impact isn't the only type of impact. Antarctica is almost completely uninhabited, and _looks_ like the last place on Earth to look for human impact - but global warming is sufficient that e.g. the thwaites glacier is on borrowed time...

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Nikita Sokolsky's avatar

All of Antarctica could melt and we would still have more than enough land/resources for 15 billion people. Same goes for every single glacier and any other natural ice deposits on the planet: we don’t need them thanks to improved desalination technologies and other methods for conserving water.

See: Israel or Las Vegas

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Jeffrey Soreff's avatar

Many Thanks and Happy New Year!

I'm making a different point. It isn't that we actively depend on Antarctica directly. My point is that Joy Hughes is basically right about being in overshoot (as technology stands today), and the fragility of even an area as far removed from direct habitation as Antarctica is a signal of how many earth systems we've put under stress.

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Nikita Sokolsky's avatar

This is exactly the mental gymnastics I’ve talked about. It substitutes the question of “carrying capacity for humans” with “carrying capacity for humans and animals both”. These are not the same questions.

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Joy Hughes's avatar

"Carrying capacity for humans" implies an ecosystem capable of supporting humans, which includes animals, plants, fungi, microbes, the oceans, soil, and atmosphere.

If, per capita, humans impact these systems less, then human carrying capacity is higher.

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Nikita Sokolsky's avatar

We can survive just fine without *any* animals and just a few plants to produce the required nutrients. We don’t need the fish, the fungi, the crustaceans, etc. We obviously need the atmosphere but it needs to get *a lot* more polluted before it represents a non trivial hazard: see Shenzen or Beijing for an example of how dirty the air can get without destroying human civilization.

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Ethics Gradient's avatar

This strikes me as a far more aggressive form of mental gymnastics: when people talk about the Earth’s carrying capacity, they don’t typically implicitly have in mind a hellish existence in a 40k hive city.

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Methos5000's avatar

But only one of them is a viable question. The only things that grow relentlessly without concern for the host are plagues and cancers, which in turn kill the host.

Let's take if we wipe out birds. Insect populations grow spreading diseases. Pollination drops. Carrion feeders aren't cleaning up carcasses another disease spreader. Loss of natural fertilizer. Damage to the forests we're already killing mean less greenhouse gas removal. What you dismiss as mental gymnastics only demonstrates you don't actually understand the ecosystem.

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Nikita Sokolsky's avatar

We don’t need birds to get rid of insects, drones and various other engineered machines can do it instead. Carcasses not getting cleaned up is already happening and hasn’t managed to wipe out a single city anywhere, so it’s a nothingburger.

Forests aren’t necessary for human survival: we could burn every single tree in the world and still sustain our current population.

The ecosystem actually required to feed 8 billion humans is far smaller than Greenpeace wants us to imagine. Anything which isn’t **strictly** required for growing wheat and corn is not a necessity.

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Joy Hughes's avatar

Is this just a thought experiment or is it something you're advocating?

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Edward Scizorhands's avatar

You can fit all of humanity into a 1km by 1km by 1km cube, slightly less if you're willing to squeeze.

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Aaron Bilger's avatar

You've just reminded me of an old Isaac Asimov essay, "The Good Earth is Dying". Written in 1970, and extremely anti-population-growth, it's rather hilarious to read now, in the context of such low fertility rates and concern about population collapse.

However, it also gives a sincere and grounded estimate on upper population capacity of Earth. Based on total plant and animal biomass, and assuming the extinction of all animals except humans and all plants but algae, Asimov calculates we could max out at about 40 trillion people.

https://s3.us-west-1.wasabisys.com/luminist/EB/A/Asimov - The Roving Mind.pdf

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Nikita Sokolsky's avatar

Great link! I don’t know if 40 trillion is accurate but I’m 99.99% confident 15 billion is realistic.

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Nikita Sokolsky's avatar

> Of course, there are creative workarounds, but they are not uniformly available

When I was in 5th grade living in Israel, my parents let me skip going to 6th grade by calling the school and saying we’re moving abroad. Nobody ever bothered to check the story and I’ve had a great school-free year.

IMO the vast majority of parents are simply too conformist to make use of trivial-to-identify workarounds. You could lay out a tried and tested solution for them that doesn’t even technically violate the law - and they’ll still choose to follow the rules, no matter how absurd the rules are.

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Shaked Koplewitz's avatar

This also feels weird about car seats. Do Americans really refuse to let kids in the car without a car seat past the age of ~2?

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Leaf's avatar

Yeah because if you don’t and someone notices you will be charged with child endangerment. The first step in rolling back this insanity is fixing the legal environment.

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5hout's avatar
4dEdited

I've had people criticize me letting my kids ride in my lap while I drive around my backyard because it'll confuse them.

It's hard to understate the ferverent belief in the car seat's power here.

Heck we even had 3 across for a trip with friends and (after the first drive) one elected to drive an extra car so we could keep it to 2 across bc the (installed per instructions) seat didn't 'feel' safe enough.

Edit: ohh, and people guilting my wife because our then 5YO was wearing a winter coat in his booster seat. That's not safe, the coat could mean he flies out from under the strap in an accident. It's 5F before wind right now, the kid is wearing a damn coat.

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Michael Bacarella's avatar

We really can't say enough about how much car seats make everything harder.

If you enjoy traveling, especially the r/onebag life, or not owning a car and just taking Ubers everywhere, having children with onerous car seat requirements will absolutely dash those ambitions.

Want to visit family on the other side of the country? Great. First challenge: getting to the airport. That means meeting the taxi, installing car seats while one parent wrestles with straps and the other tries to keep the kids from wandering off out of boredom. Ride to the airport. Then uninstall the car seats curbside at the airport, while the other parent prevents the kids from completely melting down. Try not to feel anxiety while the Uber driver watches you struggle with the latches.

Now haul the car seats along with your luggage and children through the airport. Check the car seats. Fly. Land. Pick the car seats up at baggage claim. Then do the whole thing in reverse just to get to your rental car. And yes, you will get a rental car because doing this whole dance every time you take an Uber is maddening.

This is exhausting enough with two kids. I’m fairly sure that with three, all of car-seat age, we’d need to bring a nanny simply because we wouldn’t have enough hands.

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avalancheGenesis's avatar

I am actually surprised there isn't a market for "rideshare with pre-installed car-seats". There are other service bands, like luxury rides or women drivers or paratransit...why not parent transit?

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Michael Bacarella's avatar

You can call some taxi services with carseats pre-installed but they can be pretty nasty. Children puke and spill snacks food all over.

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Jon Simon's avatar

I did some research on this recently, there exist some services like this but they are obscenely expensive and need to be booked well in advance. In some cities you can call an Uber with a car seat pre-installed, but this only works going to the airport, not coming from the airport.

A loophole in some states like NY is that taxis (but not Ubers) are exempt from the car seat requirement.

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Alex's avatar

Uber has this option in Orlando, but it costs ~2x the price of a normal Uber and only includes one car seat. Last time I went I used Tiffany Towncar Service, which offered various vehicles with different numbers of car seats and booster seats. They were great, would highly recommend. There may be similar towncar services in other cities.

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Alex's avatar

Weird, that was a standard option in Moscow 10 years ago, with Uber or its competitors. The waiting time was reasonable (10 vs 5 min for a regular ride if my memory doesn't fail me).

It wasn't pre-installed though, the driver had it in the trunk and installed it before a ride.

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Nikita Sokolsky's avatar

Aren’t taxis (and sometimes Ubers) almost universally exempt from the car seat regulations? Why not just order a taxi and not carry any car seats?

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Michael Bacarella's avatar

Almost universally? No absolutely not.

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bbqturtle's avatar

This is highly illegal and could get cps called on you. My father did this with my sisters 4 year old and she almost disowned him.

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Jon Simon's avatar

The laws differ by location. It's legal in New York.

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Nikita Sokolsky's avatar

Also legal for taxis in Seattle, for example

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Nikita Sokolsky's avatar

This conflates personal reactions with the reality of government enforcement/legislation. People being stupid about it is different from whether it’s actually possible or not.

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John's avatar

Perfect microcosm of rising tide of expectations: "I expect to be able to frequently fly with my children to arbitrary locations around the world, conveniently." Parents with 5 young kids in 1985 just....didn't travel!

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Michael Bacarella's avatar

Sure. If we unlock materialist pleasures our parents never had access to but having children is as hard (if not harder than ever, our parents didn't have this level of child car seat nonsense) we should not be surprised that there's a fertility decline.

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Dan's avatar

My dad and his 4 siblings didn’t fly but they did all pile into one car for cheap road trips from PA to FL in the 70s. I do think we’ve *way* overcorrected on car seat laws.

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MI's avatar

We have three children under 7, and have only taken road trips for 5 years now, because even if we want to buy all the plane tickets and endure the gates and flights, car seats are too much. We're considering flying to Chicago and renting an apartment near a CTA stop as a first attempt at flying with three kids, but are still waiting for the oldest to be car seat free.

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Torches Together's avatar

Having a decent train network makes things a lot easier here. I've travelled a bunch this year, flying and trains, with a baby. Car seats never crossed my mind.

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Alex's avatar

I bought RideSafer vests for my kids and they've been great for travel. They are a crash-tested and certified alternative to car seats. They pack down small enough that I can stuff two of them in a backpack on outings and still have some room for other stuff.

They do have some significant downsides: They are expensive, and they fit a smaller range of sizes than a car seat would, so you would need to buy several as your child grows. They don't provide the side impact protection that you would get from a car seat with sidewalls. It's also just more effort to put the harness on the kid and connect the seatbelt than it would be to buckle the kid into a car seat that is already installed.

All that being said, they are totally worth it and I would recommend them to anyone who is flying somewhere with small kids.

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Shaked Koplewitz's avatar

Re Israel, the underrated second factor is Israelis' willingness to just start doing things and trust in figuring them out as we go along. It's the opposite of Korean culture in that way, and it's also the reason Israel has great startups and lousy infrastructure.

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avalancheGenesis's avatar

The motherhood penalty thing...even outside of greedy careers (the salary structure for bagging groceries is pretty flat, obviously), even with pronatalist inclinations, I find myself sympathetic to the business side. We've had one manager out for over a year(!) on maternity leave at this point, with that position held open all this time at same compensation, hours, etc. Doesn't matter so much when we're at full managerial capacity, others can step up to fill the void. When we're down some though...and can't easily acquire more managers, because "on paper" she still counts as filling a spot, and it'd be awkward to only temporarily promote someone...it's just a headache. Like obviously the solution isn't to force her to come back to work, or demotion, or whatever. But children are a public good, and so having a private company subsidize this ongoing expense-in-absentia simply rankles. That's poor systems design, especially when a company does try hard for parity in hiring and promotion...shouldn't punish for doing the right thing.

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St. Jerome Powell's avatar

How did she get over a year of leave though?

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avalancheGenesis's avatar

It's not unheard of for full-time managers, and especially the Big Boss main store manager, to accrue gobsmacking amounts of PTO just in the normal course of things. Higher max weekly hourly limit sans overtime (45 I think?) plus higher pay plus higher conversion % plus [other benefits they don't make explicit to grunts like me] -> pretty normal to end up with at least a month's worth of PTO each year. You'd think this means people taking constant vacations, but the involved nature of the job and selection effects for who gets promoted (self-recommendingness is a major factor) means managers often have to be encouraged to vacation, because they won't do it enough on their own.

But yeah I don't know how it got to a year+. The official on-paper maternity/paternity leave benefit is definitely not *that* generous. Even unpaid leave for other stuff like family emergencies is supposed to cap out at around 90 days. After that, you're considered an inactive employee and need to go through (graded-on-a-curve) rehiring process, which may or may not result in same wage as previous.

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LesHapablap's avatar

You might find this article from 2021 on South Korea’s “untact” movement: an expansive government program to reduce or eliminate human contact. Absolutely absurd with the context of falling fertility. Did they consider fertility a crisis in 2021?

https://www.theguardian.com/world/2021/dec/10/south-korea-cuts-human-interaction-in-push-to-build-untact-society

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avalancheGenesis's avatar

There's a ribald "Levels of Friction" joke in there somewhere. Lots of confounding due to covid, of course, but that vision for the future is...grim. Even if there were kids to fill it.

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bbqturtle's avatar

I heard the main driver in the USA was couples are having fewer total kids. So average kids per parent was down. Like before people were having 4-5 kids and now it’s 2-3. Only children much more common.

Which in my observation is likely because of having children being opt-in vs opt-out, with the advent of contraception. Something something less Catholics, more contraception, health insurance, it being covered under Obamacare, means less ‘surprises’ as the average American rises out of poverty and can afford and is educated about contraception (And not shamed about it).

Especially IUDs. I would strongly expect total number of IUDs sold and fertility rate to be an exact, and ‘causal’ (as much as anything is) relationship.

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Frre's avatar

Rich societies don't value children enough.

Try giving 250k$ for each newborn without making ANY progress on other childhood related issue and watch fertility rates dramatically increase.

Short of this kind of financial incentives NOTHING will work.

It is saddening that after 150y+ of social experiment we haven't figured out that the right incentives rule everything.

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Victualis's avatar

Giving parents $250k will (I am registering my prediction here) mostly just lead to child-related services and expenses increasing by ~$200k, and a small increase in births. Don't subsidise demand and all that.

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Frre's avatar

This is indeed the major risk. But I'm sure we could find ways to limit it (more competition for one).

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Victualis's avatar

Zvi has certainly proposed lots of potential ways, like rolling back the norms for childcare provision to be more in line with those some decades ago.

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avalancheGenesis's avatar

That tweet from Jakob is excellent. Yeah, it's great that we've moved to "opt-in", not everyone should have kids, it's a sign of wealth and progress that many societies are rich enough to support a sizeable population of DINKs and happily-singles. But then the flip side is having this crisis of meaning, where all these people who should be busily self-actualizing just seem to mostly...sit on their thrones, waiting for life to go by. Which is doubly depressing to see for those of us who do want kids and (physically) can't have them. Many ways to contribute to the commons besides having kids, but those mostly don't happen either.

It's also funny how often reactionaries like Pollnow or Helen Andrews do the Mark Rosewater thing: good at noticing and articulating there's a problem, terrible at offering solutions. Many Such Cases besides natalism.

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Ethics Gradient's avatar

Are we sure the crisis of meaning isn’t an essentially a characteristic of the universe rather than an incorrect projection thereon? Consider the AI situation: probably around 2,000-10,000 people out of all of human civilization are actually dictating the future of human technology and of (human or otherwise) civilization. “You have to be in the top 0.000001% of genetic and circumstantial luck to have a chance of exercising enough agency not to have your life’s legacy washed away like a sandcastle by the tide of history and your work comprise the essentially fungible historical equivalent of filing TPS reports” isn’t exactly false.

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avalancheGenesis's avatar

But it has always been thus. "Human scaling laws" always meant that only a tiny percentage of the cream of the crop of the upper crust had any meaningful impact on the future of human technology and of (human or otherwise) civilization. It's true, the fruits used to be lower, and when civilization is just a bunch of mud huts it's easy to break off and found a new paleosuburb or whatever. But - I like having those fruits experiencing gravity! I like living in a developed country! And my life and my work have meaning to me and the people around me. Every day is a chance to do a bit of good, enjoy the hard-won bounty of the past, and support those brave souls trying to carry the torch into the future. This is enough; I don't need to be a torchbearer myself, or a queen, or a capabilities researcher. (Although I am all those things, at the local scale. Scale is all you need.)

Humanity has struggled with finding its place in the cosmos for thousands of years, and has come up with myriad different ways to address the problem. If philosophy isn't enough - if religion isn't enough - if having kids isn't enough - if hedonism isn't enough - if fighting for a cause isn't enough (God knows there's plenty that will still be very important in "AI fizzle" timeline) - if doing tractable good via service and altruism isn't enough - then I'm not sure what to tell you. Even accelerationists like Robin Hanson would say that poor folks do smile. Yes, defeating death would mean never losing another von Neumann ever again - but it also means saving a thousand thousand thousand TPS cover sheets of Peter Gibbons, Michael Bolton, Samir Notgonnaworkhere, Bill Lumberg, even Milton. Did you get the memo? Fuckin' A, those lives have value too, both in the past tense and in the future. The lightcone would be a very lonely place indeed if we only had the 0.000001%.

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John's avatar

One unanswered question I have, relevant to the "culture is fixed, biology is mutable" perspective: what would the fertility rate in the United States be if all couples with (medical) fertility problems were immediately able to conceive? As in, suppose tomorrow Pfizer debuts a miracle fertility drug that can make any woman up to age 50 naturally conceive a child with the same health profile as a 25-year-old mother, and no negative side effects. And suppose the government immediately provides this drug for free. How much would fertility go up? Is making better IVF / preventing declining (medical) fertility with age a viable solution here?

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Daniel Sosebee's avatar

> 100 people today → 25 children → 6 grandchildren → 4 great-grandchildren.

That’s it. Game over for an entire nation by ~2125 if fertility stays where it is (0.68–0.72)

Am I missing something?

100*0.7^3=34.3 in three generations… not even close to “4 great grandchildren”?

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Jeffrey Soreff's avatar

0.7 per woman, not per person (male or female), so 0.7 TFR is (roughly) 0.35 per person.

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Daniel Sosebee's avatar

Oh wow thank you for clarifying. That is really low

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Miston's avatar

It says safe multiple kid car seats are widely used in Europe but the fertility rates in Europe are abysmal, so that seems to point to the car seats not making a difference?

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St. Jerome Powell's avatar

Uh, Europe vs US is not exactly holding everything equal except car seat policies? Europeans don’t even drive, in lots of cases.

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Squiffy's avatar

I think these type of seats are a red herring. The seats liked to are a 'multimac' - which is basically a bench you install that gives you 3 or 4 across. But, they are very expensive ($2-3k to buy) plus hard to install (you have to rip out your back seats, and bolt it in I think - i think the install is usually another $1.5k). So this does not fix the 'you have to expensively change/fix your car if you want another kid' problem.

The car seat thing is a real problem. I have a 3rd baby on the way, and have a Tesla Model Y - a big car. It's a major headache finding how to fit 3 seats across, took much research and I had to buy a new expensive super slim car seat to make it work, and then only just. All the seat are just too wide and bulbous, and the car's seatbelt sockets are inset and too hard to access. And this is a big car! My sister in law, who now has 3 kids and a Model Y, is gunning to get a 7 seater - which all cost $$$

I'm not sure changing the laws here will help that much. It's the whole 'rising expectations' thing. People want their kids to be safe, and that means using car seats. Even when allowed you don't feel good taking your kid in a car without out, and would only do so on short journeys.

What would help is slimmer seats being available (this might be a testing standards thing) and standard family cars better designed around 3 across seats (more width in the back seat area, isofix parts shunted more to the side, isofix in the middle seat, more accessible seat belt sockets that aren't inset etc).

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bbqturtle's avatar

I have enough issue with 1 car seat in my MY. It is such a hassle it does make you kind of think about how hard more kids would be. Good luck with 3 back there! Why are those stupid clips so far in? Haha

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Edward Scizorhands's avatar

We need foldable netting so the kids are basically flat against the back seat. Packs up easy.

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Neural Foundry's avatar

Brilliant piece tracing how safety culture metastasizes into anti-natalism. The car seat testing fixture thing is wild in particular because it shows regulatry intertia at its most absurd. We can't even test safer multi-kid seats bcause the testing equipment itself is outdated, yet families are the ones making the tradeoff between having another kid or keeping their sedan. I watched my brother deliberate over this exact calculus last year, car replacement vs third child, which felt dystopian in real time.

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Jeffrey Soreff's avatar

Re "Robots, AI and automation might mitigate the effects along the way and prevent total societal collapse for a while, but there would soon be no one left to constitute the society. It would cease to exist."

A couple of possible scenarios (in the class of we-manage-to-control-AI set of scenarios, which I guess at being something like 50% likely):

a) If we fully automate the economy, and have enough productivity that UBI can maintain or improve the standard of living that we (in the 1st world) have now:

- parents who no longer need to work have time available for child care

- the career progression penalty for women goes away

- the scramble for positional educational goods no longer makes sense, so e.g. hagwon goes away

b) even if all that fails, and human population goes into around 2X shrinkage per generation - well, humans won't be the only entities that can constitute the society. I'd expect AGIs to continue at least our technological achievements, and quite probably our scientific (and _maybe_ cultural) ones as well. This is the softest version of a biological to machine civilization transition.

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Antipopulist's avatar

You should look at this article, which explains both the Baby Boom in the USA and the recovery of fertility in Kazakhstan: https://www.aporiamagazine.com/p/the-baby-boom

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Arbituram's avatar

I'm not convinced. This doesn't explain the even worse fertility in East Asian countries, which don't have many of the things you mention like robust welfare states, and much worse women's rights.

Within Europe, social conservatism is negatively correlated with fertility. France and Sweden, although sub replacement, are doing better than everyone else even excluding immigrants.

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Antipopulist's avatar

This helps explain East Asian fertility a bit: https://www.richardhanania.com/p/the-east-asian-package

The basic idea for East Asia is that the people there are ultra-conformist, and babymaking fell out of being the standard pathway, so you saw colossal fertility declines as the preference cascaded.

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Matthias U's avatar

"The first explanation is that wives are treated rather horribly by their in-laws and new family, which I can totally see being a huge impact but also isn’t at all new?"

Women now have options, or at least more information -- being able to watch heaps of videos that show women in other areas of the globe who don't need to kowtow to their husbands, or even get along just fine without one, has a huge impact.

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