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Comment by didip | Hacker News Reader

Will humanity go extinct if our birth rate continues to plummet?

Probably not. Birth rate depends on a lot of variables, including how wealthy a society is. If birth rates dropped to a level that was making us poorer, people would start reproducing more to compensate. Also, wealthy societies can manage the birth rate through tax cuts and other incentives.

The correlation is complex and im not sure its well understood though. You need to be rich to raise kids, but people in poor countries have more children. Also, Japan (and parts of Europe). They don't seem to control birth rate although quite rich.

Japan gives an allowance [1] to families with children under a certain age, in addition to other tax incentives, parental leave policies, and subsidized child care. Similar policies exist in many countries in Europe.

[1] https://en.wikipedia.org/wiki/Kodomo_Teate_Law

Sure, my point being that it does not seem to work very well ; Japanese population is aging.

No, even with lower birth rates there are going to continue to be many, many humans on earth.

If fertility rates remain below replacement levels, then eventually we will go extinct. How far below replacement determines how quickly this will happen.

Human population is still growing faster than we can manage long term, so it's way too early to worry

The low fertility rate is not very uniform across cultures. Some pockets of society have high fertility rates which would keep things going. Also, fertility rate cultural norms can easily reverse a few generations down the line.

I'm speaking of the overall, global fertility rate, which is currently around 2.3.

If there are fewer people, there's less competition and more resources, people get more stuff, people get happier, and have more children.

Happier people with more resources have fewer children.

Poor people who lack resources have more children.

Yes, and at current rates it would take many, many generations for extinction to occur. Do the math with whatever birth rate you want to use. It’s not like birth rate is likely to stay constant over such a long period, either.

The current trend does not determine long-term future behavior, any more previous trend of rapidly rising population did.

There's been at least a couple points in history when the homo sapiens population was <10,000... the current population is 8.1 billion. Seems unlikely, and certainly not something we'll personally have to worry about.

The overall population numbers might drop, but not in our lifetime (it is forecasted to continue to go up until at least 2100). Once you are dead you will cease to exist, so whether humanity goes extinct 1 minute after you die or 1 million years after you die, as far as you are concerned it is the same.

I have children that I hope live far beyond my death, and hopefully grandchildren after that, so I actually do want the future to be there for them, regardless whether I'm around.

> whether humanity goes extinct 1 minute after you die or 1 million years after you die, as far as you are concerned it is the same.

I take it you haven't drafted a will, and don't plan to?

I plan on dying with as close to zero debts and zero assets as possible.

Why zero debts?

Any debts I have are ones I incurred. The moral thing to do is to pay off my own debts. If I don’t want to pay a debt, I shouldn’t have incurred the debt in the first place. Though, when I say debt I am talking about things like loans and credit card debt and not medical debt that might arise through an accident.

But once you are dead you will cease to exist, so whether you have no debt or 1 million dollars of debt, as far as you are concerned it is the same.

I don't see the connection between doing the right thing before I die and not existing after I die.

I don't understand a moral framework that's concerned with the posthumous status of one's financial obligations but is unconcerned with the future continuation of the human race.

I don't see the distinction between paying my debts in advance of my death, versus establishing in my will that my debts will be repaid from my remaining assets.

Nor do I see a major moral distinction between, say, setting off a nuclear bomb timed to explode one microsecond after your death, versus one microsecond before it.

I’m sure Citibank will light a candle for you, once you are gone. Blessed debt repayer!

It won't remain at low levels once population has shrunk a lot. The greater availability of space and the collapse of complex society will likely trigger a population boom before we get to 100 million.

Perhaps if half a generation didn't feel locked out of traditional family things like home ownership they wouldn't feel so adverse to traditional family things like having kids.

Tautologically, yes.

With you as a last man standing maybe.

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