Hacker News Reader

I think there a few flaws with your thoughts

> A stabilizing population on an island with limited space seems like a good thing. A little more space opens up for living and real-estate prices might become more favorable. Maybe there's room for more parks and other things that make life good. When conditions become more favorable, people will be able to reproduce more.

Population density is not homogenous. Excluding pandemic era, the trend has been decreasing population density in the countryside and smaller cities, while more population moves to the big cities. In general, population size need not correlate for the average persons lived population density.

> I'd say that the human desire for reproduction might work in the same way, only instead of prey, maybe real-estate prices and quality of life is the cyclical variable to note.

This is likely true on the extremes to some degree, but I haven’t seen much evidence that this is a driving force of population dynamics.

> I've never understood why there was such an extreme panic by some about Japan's lower birth rates to the point that they urged mass immigration there.

This is generally because the population is not stabilizing, it’s on the verge of collapsing. If fertility rate rises “naturally” in the future, as you suggest, then it’s obviously not an issue. But maintaining a 1.3 or lower fertility rate indefinitely will result in an exponential decay of population which could itself result in a decline of living standards. For example, if the population decreases too much to support a high speed rail system so these are abandoned as unprofitable.

>> I'd say that the human desire for reproduction might work in the same way, only instead of prey, maybe real-estate prices and quality of life is the cyclical variable to note.

>This is likely true on the extremes to some degree, but I haven’t seen much evidence that this is a driving force of population dynamics.

In South Korea, young people are struggling to find affordable places to live, to the extent that many people live with their parents well into their 30ies. Coincidently, they also have one of the lowest birth rates in the world.

In my city, I see a lot of people who first build a house or buy an appartement, and then have kids, in their 30ies, because they can't afford a big enough place before that.

As housing prices rise everywhere, it takes longer and longer for people to be able to afford a place big enough for a family. Of course people then delay having kids, and many end up not having kids at all.

GDP can’t go up without strong reproduction and/or immigration. The economy stagnates and government debt becomes massive, which is what you see with Japan.

The scary thing is that this is something the USA and lots of other countries are headed towards as well.

https://dailyinfographic.com/government-debt-by-country

GDP can grow with a stable population if your Real gross domestic product per capita is growing which it has been for the USA [0]. Japans has barely grown for the past 30 years which is their big problem [1].

[0]: https://fred.stlouisfed.org/series/A939RX0Q048SBEA

[1]: https://fred.stlouisfed.org/series/NYGDPPCAPKDJPN

What do you think the cause is for the differences? I strongly feel that a lot of that latter “strength” for the USA chart after 2009 was made up of money printing.

https://fred.stlouisfed.org/series/M2SL

https://inflationchart.com/gdp-in-m3

I guess we will see if USA can continue up only. I have my doubts. Fertility rate needs to be 2.1 to remain stable and we dipped below 2.0 around 2010 and are at 1.64 now (Japan is 1.34). The previous US administration clown show also drastically cut immigration.

https://www.weforum.org/agenda/2022/06/global-decline-of-fer...

> The previous US administration clown show also drastically cut immigration.

What if restricting immigration for a time is what is needed to start to stabilize the birth rate which ultimately takes care of the economy?

Many Americans aren't focusing on making babies because they're hopeless about their future and ever having a home so they put off thinking about having a family until as late as possible. What if a more modest amount of immigration (lowering demand for housing) helps put home ownership and hope for the future into more peoples' reach? A little reduction in real-estate prices might piss off some boomers who have a lot of wealth locked into their home, but these aren't the people who are going to be reproducing.

Cause and effect are sometimes related in unexpected ways, but this chain of thinking about this problem seems entirely simple and rational.

I suspect that home prices and ownership rates don't explain birth rates. Who says you can't rent and have children? A large part of the world already does it.

Birth rates go down with economic development, and the growth of freedoms and opportunities for women. It's a tale seen everywhere. And all the other fun stuff and distractions available for young people today - dating apps, video games, pop culture, avocado toast, too many hobbies to name - competes with child-rearing for time, attention, and money. Even as a parent, I sometimes long for a more carefree life. I'm sure a lot of people see their peers with children and decide, rationally, to not pursue parenthood.

(This is without even getting into the climate crisis).

The birth rate is so low around the world that we may see peak population by 2060 (worst case) and then an exponential decline. Quality of life will decrease as the number of old people drastically out numbers the young people.