7 ms·

My hot take, as we approach the equilibrium population in the world (perhaps the sustainable carrying capacity), fertility rates will naturally decrease. Some

My hot take, as we approach the equilibrium population in the world (perhaps the sustainable carrying capacity), fertility rates will naturally decrease. Some countries have already exceeded their equilibrium populations; therefore, their fertility rates will decrease below replacement rates for some time until they reach equilibrium (which is not 0, which fearmongers may promote). As climate change progresses, it may be the equilibrium population is even lower than we expect right now.

pier25 3y ago
> My hot take, as we approach the equilibrium population in the world (perhaps the sustainable carrying capacity), fertility rates will naturally decrease. We already surpassed that point of equilibrium long ago. Humanity is now consuming 1.7 Earths of resources every year. Some countries like the US consume a lot more than that. https://www.overshootday.org/how-many-earths-or-countries-do-we-need/ https://www.overshootday.org/how-many-earths-or-countries-do...
- LUmBULtERA 3y ago
  Oh, I agree. It's just strange to me that there seem to be more and more alarmists that speculate that populations will go to 0 or something. With greater and greater amounts of automation available to us, I personally don't see a falling population to be a huge problem.
- s1artibartfast 3y ago
  I dont think that is a particularly helpful metric. If you are spending 1.7x your income, how much money you have in the bank becomes extremely relevant. Are you broke tomorrow, or do you have enough savings for 1,000 years
  - pier25 3y ago
    The important part is that you can't just make more natural resources, unlike money. In some cases we've already passed the peak of certain resources. See this paper about peak minerals from 2012. https://www.sciencedirect.com/science/article/abs/pii/S0959378011001361 https://www.sciencedirect.com/science/article/abs/pii/S09593...
    - s1artibartfast 3y ago
      I hear what you're saying and that is an important consideration as well, but it's very different than saying 1.7 Earths. If someone makes a fraction like that the denominator is relevant. The charitable assumption is that it is 1.7 of the replenishment rate for a given resource. If it's a non replenishable resource, the fraction doesn't make any sense. We're not using 170% of a finite resource per year every year. If you have a finite, non-replenishable resource, then you need a budget for how long you want it to last to come up with a consumption Target.
NoMoreNicksLeft 3y ago
Please explain how a population that sees its fertility rate voluntarily drop below replacement will ever have it raise back up to replacement level. No little girl who grows up seeing few, if any women, have children will think to herself "I want 2.1 when I grow up!". But, all must do this, or fertility rates never recover. If not all girls do that, then some must instead say "I want 4.5 when I grow up" or "I want 8.9 when I am a woman"... which seems even less likely. It's an inevitable, inescapable mathematical fact.
- LUmBULtERA 3y ago
  People are responding to incentives. Costs, including opportunity costs, increase substantially when we're beyond the equilibrium population. As population declines and constraints ease, the costs of having children will decrease, and fertility rates will increase. All women will not need to have 2+ children for an equilibrium. Some women and families will want 0 or 1, and some will want more. But in any case, people obviously respond to incentives, and the people who think there is an "inescapable mathematical fact" that population will simply continue trending to 0 ignore this fact entirely.
  - twelve40 3y ago
    this has never been done for any sustained period in any society ever, despite incentives of all kinds that were tried in the past. All human experience so far has been: this trend is irreversible. But, you came up with this random idea that a little economic reshuffling will quickly fix things when needed. How do you know that? You also came up with the idea that it's really no big deal, even though the prime minister of Japan and other authorities publicly say that they are losing their ability to function as a society and this trend is hurting them very much already. So much for "not a huge problem" and "it's just silly fearmongering".
    - NoMoreNicksLeft 3y ago
      He seems to think that the "constraints will ease" as the Japanese economy implodes even further. It might even be true that with the right incentives, they could convince the childless to have children. Unfortunately, he doesn't seem to get that just because there is a theoretical incentive that could work doesn't mean that same theoretical incentive is anything anyone could hope to afford.

pier25 3y ago

> My hot take, as we approach the equilibrium population in the world (perhaps the sustainable carrying capacity), fertility rates will naturally decrease. We already surpassed that point of equilibrium long ago. Humanity is now consuming 1.7 Earths of resources every year. Some countries like the US consume a lot more than that. https://www.overshootday.org/how-many-earths-or-countries-do-we-need/ https://www.overshootday.org/how-many-earths-or-countries-do...

LUmBULtERA 3y ago
Oh, I agree. It's just strange to me that there seem to be more and more alarmists that speculate that populations will go to 0 or something. With greater and greater amounts of automation available to us, I personally don't see a falling population to be a huge problem.
s1artibartfast 3y ago
I dont think that is a particularly helpful metric. If you are spending 1.7x your income, how much money you have in the bank becomes extremely relevant. Are you broke tomorrow, or do you have enough savings for 1,000 years
- pier25 3y ago
  The important part is that you can't just make more natural resources, unlike money. In some cases we've already passed the peak of certain resources. See this paper about peak minerals from 2012. https://www.sciencedirect.com/science/article/abs/pii/S0959378011001361 https://www.sciencedirect.com/science/article/abs/pii/S09593...
  - s1artibartfast 3y ago
    I hear what you're saying and that is an important consideration as well, but it's very different than saying 1.7 Earths. If someone makes a fraction like that the denominator is relevant. The charitable assumption is that it is 1.7 of the replenishment rate for a given resource. If it's a non replenishable resource, the fraction doesn't make any sense. We're not using 170% of a finite resource per year every year. If you have a finite, non-replenishable resource, then you need a budget for how long you want it to last to come up with a consumption Target.

NoMoreNicksLeft 3y ago

Please explain how a population that sees its fertility rate voluntarily drop below replacement will ever have it raise back up to replacement level. No little girl who grows up seeing few, if any women, have children will think to herself "I want 2.1 when I grow up!". But, all must do this, or fertility rates never recover. If not all girls do that, then some must instead say "I want 4.5 when I grow up" or "I want 8.9 when I am a woman"... which seems even less likely. It's an inevitable, inescapable mathematical fact.

LUmBULtERA 3y ago
People are responding to incentives. Costs, including opportunity costs, increase substantially when we're beyond the equilibrium population. As population declines and constraints ease, the costs of having children will decrease, and fertility rates will increase. All women will not need to have 2+ children for an equilibrium. Some women and families will want 0 or 1, and some will want more. But in any case, people obviously respond to incentives, and the people who think there is an "inescapable mathematical fact" that population will simply continue trending to 0 ignore this fact entirely.
- twelve40 3y ago
  this has never been done for any sustained period in any society ever, despite incentives of all kinds that were tried in the past. All human experience so far has been: this trend is irreversible. But, you came up with this random idea that a little economic reshuffling will quickly fix things when needed. How do you know that? You also came up with the idea that it's really no big deal, even though the prime minister of Japan and other authorities publicly say that they are losing their ability to function as a society and this trend is hurting them very much already. So much for "not a huge problem" and "it's just silly fearmongering".
  - NoMoreNicksLeft 3y ago
    He seems to think that the "constraints will ease" as the Japanese economy implodes even further. It might even be true that with the right incentives, they could convince the childless to have children. Unfortunately, he doesn't seem to get that just because there is a theoretical incentive that could work doesn't mean that same theoretical incentive is anything anyone could hope to afford.