Hacker News Reader

Comment by riffic | Hacker News Reader

> go extinct

Wouldn't this be more of a Ship of Theseus scenario than outright extinction?

Only if they allow immigration.

I just don't have the imaginative capabilities of seeing the entire archipelago depopulated but I suppose it's possible.

Yeah, actual extinction seems impossible, if for no other reason that at some point above "0" the population will no longer be able to sustain a functioning government, and a non-functioning government isn't going to be able to regulate immigration.

If current rates continue, which is a big assumption, then Japan will have 106M people by 2050 and 75M by 2100, which was roughly the population before WW2. Japan is already one of the most densely populated areas in the world, so further population growth may not be the greatest idea. They already have good standards of living, great infrastructure, high societal trust, low crime, a competent government, etc. Europe's strategy of importing millions of low skill foreigners who are mostly dependent on welfare and have destabilized their societies is also probably not a great idea either.

These population projections also ignore the many factors that may change. As the population declines, more opportunities may open for young people, leading to increased family formation. The culture may evolve in response the lopsided demographic pyramid, causing increases in the fertility rate. People are already predicting AGI in the next couple decades, which will render most people unnecessary anyway. These classical analyses around demographics will probably become increasingly obsolete.

> 106M people by 2050 and 75M by 2100

of those, most will be old. Population before WW2 was a much healthier mix of old, working age and children.

Who will cater to all the old? Who will pay for the social safety net programs?

This isn't quite accurate. The population projection graphs you see [1] are based on UN numbers which have the Japanese fertility rate skyrocketing [2] relative to past trends, presumably based on the assumption of some sort of successful social policy. That's why the collapse starts to smooth out in the graph, which is not what you see from a constant rate. Fertility rates, at a constant level, are brutally exponential systems which do not 'slow down'.

As for predictions, I remember about 10 years ago making fun of somebody who wanted to get a class C (commercial trucking) license. It seemed like the most idiotic idea imaginable at the time. Self driving vehicles had already been proven viable and surely it was imminent that nobody would be driving themselves around, let alone truckers where companies would love to ditch those relatively hefty labor fees. Relevant link: https://en.wikipedia.org/wiki/Sigmoid_function

---

[1] - https://www.macrotrends.net/countries/JPN/japan/population-g...

[2] - https://www.macrotrends.net/countries/JPN/japan/fertility-ra...

> Fertility rates, at a constant level, are brutally exponential systems which do not 'slow down'.

If fertility rates are correlated to your ancestor's fertility rates, then a decline can "slow down" just because the remaining people of fertile age will be disproportionately from families with higher fertility rates.

Reply on news.ycombinator.com