As an energy investor I watch this issue. Effects likely beyond my lifetime (though markets discount the future pretty well).
As a Classical Liberal, I worry that the birth rates are collapsing in the “free” or Enlightened world, but maintaining in the backward ones. The Benighted shall inherit the Earth? By default?
Thank you sir. Perhaps it is this development, along with AI and quantum computing achieving scale, that will shake us out of our lingering 20th Century torpor. There is a case for optimism in all of this, especially if we look to the stars.
To bring this closer to climate change policy we need to incorporate the best demographically informed objections of global GDP growth (including the effects of alternative policies ON GDP) in order to estimate the NPV of different policy sets. Presumably -- although this should be done properly not "presumed" -- this means lowering the optimal trafjectory of the tax on net CO2 emissions or equivalent policies
One of my favorite views on this comes from Hans Rosling's 2018 book, Factfulness. In it are two charts showing the same basic information: Children surviving to age 5 and family size (babies per woman). Each chart is divided into two separate groups: Developing countries and Developed Countries. One chart is as of 1965. The other is as of 2017.
In the 1965 chart, there are 125 countries including China and India in the Developing Country group.. In those countries, women have more than 5 children, on average, and more than 5% of children died before their 5th birthday. In the Developed country group, there were 44 countries with family size of fewer than 3.5 children and child survival rates above 90%.
IN 2017, the picture had completely changed. The Developing country box contains only 13 countries (6% of the world's population) and most of the world's population is now in the Developed country box.
As countries have made the shift from Developing to Developed extreme poverty has been vastly reduced and the populations are able to sustain smaller families with a better life style.
Fifty years ago and earlier, we could not imagine a future with these demographic changes and the thought of increasing population was baked in.
As the adage goes, "In theory, theory and practice are the same, in practice they are not." The dynamics of family life have changed and that will drive population growth or decline.
My takeaway, If, by chance or luck, my lifespan is extended another 80 years, and the promise of AI ends up being vaporware, what I have to look forward to in the next 100 years if my retirement is...more and more work...
When I see a lot of decimal places in some government or NGOs reports, my BS detector goes off. I wonder how many people are getting paid by government funded agencies to make double decimal place predictions that can't possibly be accurate.
I sleep better at night thinking that one day the world population will peak and then diminish. Why say more. Hopefully it will drop to a level that will leave a world population of 4 billion or so. And I hope they all have a standard of living above that average person in the world currently.
Think of this as a share buy back. Fewer and more committed and better connected people on Earth. And by default fewer government employees putting too many decimal places in their calculations!!!!
No 4B is way too low. A population of about 10B is optimal. @ 4B much of our technological, industrial, information processing, space & agricultural capabilities will be severely hindered.
In actual fact we need that ability to achieve what should be the overriding goal, space exploration, planetary protection and creating a World industrial civilization that mimics the tropical rainforest, almost total recycling of everything and minimal impact on terrestrial biological systems. That is all quite achievable. But only with plentiful, clean energy. That is nuclear energy.
With low fertility rates in high income countries, these are getting older and less populous with needs that are different from those of low income and high fertility rate countries with young populations.
In this respect, the Occident has a problem...
The change of fertility rate can take place in a relatively brief period: in Spain from 2.8 in 1975 to 1.15 20 years later.
Excellent piece. I have argued before that the UN forecasts are too high. The methodologies of Wolfgang Lutz and colleagues at The Wittgenstein Centre and the IMHE are better:
Rather than overpopulation – a concern that started in the late 1960s just as fertility peaked! – we should be planning for depopulation. Part of that will be looking to AI and robotics. Another part will be research to extend the healthy human lifespan. Policies to increase fertility just have not worked.
Increasing fertility will take a lot more than policies. It will take a major reform of our political structure. The worst thing possible is our current top-down Totalitarian Fascist World Tyranny that is developing right before our eyes. Fertility will continue downward under such a fanatical oppressive governance.
Such a badly-needed reform of our political structures looks increasingly unlikely to me which puts a major dent in my overall optimism. The best hope seems to be to get away from existing states and build new economies and societies in space. However, that's decades away at best. Keep the dream alive!
I am interested in your thoughts on the book "The End of the World is Just the Beginning" by Peter Zeihan. He has a lot to say about population growth/de-growth, globalization and economic outlooks for various parts of the world. He sees deeper and quick reductions in population. He discusses impacts on climate as well (not his strong suit in my opinion).
If you model declining birth rate of say 1.1, I believe it goes into an unstable acceleration (of decline) that is virtually impossible to alter. It would be interesting for somebody to do this demographic mathematical modeling.
Peter Zeihan in "The End of the World is Just the Beginning" does this type of modeling for different parts of the World. My understanding of his work is that indeed using sharply declining birth rates predicts unstable acceleration for some parts of the Globe. His conclusions re. China are particularly surprising.
There’s one idea going around that genetic impacts on fertility will overcome other drivers to re-accelerate population ie evolution will favour genetics predisposed to bear more children. Does Zeihan or anyone else you’re familiar with address this? It comes down to a question of biology vs. culture I suppose.
Right, I have seen his work and read his book. I think you have it right and that’s where I learned the concept. The Italians and the Russians are in similar circumstances.
Excellent post! I expect energy consumption per capita is going to continue to increase, esp. in the developing countries. So, too, an increase in total energy consumed. However, once "peak people" is reached, shortly after we should see peak energy consumption, as consumption per capita is overtaken by the decreasing number of "capitas."
Perhaps more important than the world population are the national population projections. Maybe even the sub-national breakdowns of exactly who is having children and who is not.
The climate connection is very vague -- energy use will increase regardless of total population, and may in inversely associated -- less people more energy use.
Burgeoning populations in energy poor countries will rapidly increase energy demand in those areas: Africa, South America -- already doing so in India and as China pushes to increase population.
Your piece on Culling for Climate is the real motivation for the IPCC et al. to focus on total world population.
Excellent work sir. Thank you. A question. You hypothesize that some in the climate community will resist suggestions of demographic change. I agree with that hypothesis, but how does it reconcile with those in the climate community who wish to cull population, which you wrote about last week. That essay, by the way, was downright scary, to me. That we have responsible people who would wish for the collapse of civilization suggests our times are no better than they were in 1935.
As an energy investor I watch this issue. Effects likely beyond my lifetime (though markets discount the future pretty well).
As a Classical Liberal, I worry that the birth rates are collapsing in the “free” or Enlightened world, but maintaining in the backward ones. The Benighted shall inherit the Earth? By default?
Vaclav Smil in his book Grand Transitions explores the eventual population reduction. Highly recommend it.
Thank you sir. Perhaps it is this development, along with AI and quantum computing achieving scale, that will shake us out of our lingering 20th Century torpor. There is a case for optimism in all of this, especially if we look to the stars.
To bring this closer to climate change policy we need to incorporate the best demographically informed objections of global GDP growth (including the effects of alternative policies ON GDP) in order to estimate the NPV of different policy sets. Presumably -- although this should be done properly not "presumed" -- this means lowering the optimal trafjectory of the tax on net CO2 emissions or equivalent policies
One of my favorite views on this comes from Hans Rosling's 2018 book, Factfulness. In it are two charts showing the same basic information: Children surviving to age 5 and family size (babies per woman). Each chart is divided into two separate groups: Developing countries and Developed Countries. One chart is as of 1965. The other is as of 2017.
In the 1965 chart, there are 125 countries including China and India in the Developing Country group.. In those countries, women have more than 5 children, on average, and more than 5% of children died before their 5th birthday. In the Developed country group, there were 44 countries with family size of fewer than 3.5 children and child survival rates above 90%.
IN 2017, the picture had completely changed. The Developing country box contains only 13 countries (6% of the world's population) and most of the world's population is now in the Developed country box.
As countries have made the shift from Developing to Developed extreme poverty has been vastly reduced and the populations are able to sustain smaller families with a better life style.
Fifty years ago and earlier, we could not imagine a future with these demographic changes and the thought of increasing population was baked in.
As the adage goes, "In theory, theory and practice are the same, in practice they are not." The dynamics of family life have changed and that will drive population growth or decline.
My takeaway, If, by chance or luck, my lifespan is extended another 80 years, and the promise of AI ends up being vaporware, what I have to look forward to in the next 100 years if my retirement is...more and more work...
Demographics is destiny.
I don't think demographics is destiny anymore. Or at least not within a few decades, given present progress in robotics:
https://bostondynamics.com/atlas/
https://www.youtube.com/watch?v=cpraXaw7dyc
https://www.youtube.com/watch?v=rTiL9R_Q5PA
When I see a lot of decimal places in some government or NGOs reports, my BS detector goes off. I wonder how many people are getting paid by government funded agencies to make double decimal place predictions that can't possibly be accurate.
I sleep better at night thinking that one day the world population will peak and then diminish. Why say more. Hopefully it will drop to a level that will leave a world population of 4 billion or so. And I hope they all have a standard of living above that average person in the world currently.
Think of this as a share buy back. Fewer and more committed and better connected people on Earth. And by default fewer government employees putting too many decimal places in their calculations!!!!
No 4B is way too low. A population of about 10B is optimal. @ 4B much of our technological, industrial, information processing, space & agricultural capabilities will be severely hindered.
In actual fact we need that ability to achieve what should be the overriding goal, space exploration, planetary protection and creating a World industrial civilization that mimics the tropical rainforest, almost total recycling of everything and minimal impact on terrestrial biological systems. That is all quite achievable. But only with plentiful, clean energy. That is nuclear energy.
With low fertility rates in high income countries, these are getting older and less populous with needs that are different from those of low income and high fertility rate countries with young populations.
In this respect, the Occident has a problem...
The change of fertility rate can take place in a relatively brief period: in Spain from 2.8 in 1975 to 1.15 20 years later.
Excellent piece. I have argued before that the UN forecasts are too high. The methodologies of Wolfgang Lutz and colleagues at The Wittgenstein Centre and the IMHE are better:
https://maxmore.substack.com/p/overcoming-population-arguments-to
Rather than overpopulation – a concern that started in the late 1960s just as fertility peaked! – we should be planning for depopulation. Part of that will be looking to AI and robotics. Another part will be research to extend the healthy human lifespan. Policies to increase fertility just have not worked.
Increasing fertility will take a lot more than policies. It will take a major reform of our political structure. The worst thing possible is our current top-down Totalitarian Fascist World Tyranny that is developing right before our eyes. Fertility will continue downward under such a fanatical oppressive governance.
Such a badly-needed reform of our political structures looks increasingly unlikely to me which puts a major dent in my overall optimism. The best hope seems to be to get away from existing states and build new economies and societies in space. However, that's decades away at best. Keep the dream alive!
I am interested in your thoughts on the book "The End of the World is Just the Beginning" by Peter Zeihan. He has a lot to say about population growth/de-growth, globalization and economic outlooks for various parts of the world. He sees deeper and quick reductions in population. He discusses impacts on climate as well (not his strong suit in my opinion).
If you model declining birth rate of say 1.1, I believe it goes into an unstable acceleration (of decline) that is virtually impossible to alter. It would be interesting for somebody to do this demographic mathematical modeling.
Peter Zeihan in "The End of the World is Just the Beginning" does this type of modeling for different parts of the World. My understanding of his work is that indeed using sharply declining birth rates predicts unstable acceleration for some parts of the Globe. His conclusions re. China are particularly surprising.
There’s one idea going around that genetic impacts on fertility will overcome other drivers to re-accelerate population ie evolution will favour genetics predisposed to bear more children. Does Zeihan or anyone else you’re familiar with address this? It comes down to a question of biology vs. culture I suppose.
Right, I have seen his work and read his book. I think you have it right and that’s where I learned the concept. The Italians and the Russians are in similar circumstances.
Great summary, analysis, and update, thanks Professor!
Excellent post! I expect energy consumption per capita is going to continue to increase, esp. in the developing countries. So, too, an increase in total energy consumed. However, once "peak people" is reached, shortly after we should see peak energy consumption, as consumption per capita is overtaken by the decreasing number of "capitas."
Perhaps more important than the world population are the national population projections. Maybe even the sub-national breakdowns of exactly who is having children and who is not.
The climate connection is very vague -- energy use will increase regardless of total population, and may in inversely associated -- less people more energy use.
Burgeoning populations in energy poor countries will rapidly increase energy demand in those areas: Africa, South America -- already doing so in India and as China pushes to increase population.
Your piece on Culling for Climate is the real motivation for the IPCC et al. to focus on total world population.
Excellent work sir. Thank you. A question. You hypothesize that some in the climate community will resist suggestions of demographic change. I agree with that hypothesis, but how does it reconcile with those in the climate community who wish to cull population, which you wrote about last week. That essay, by the way, was downright scary, to me. That we have responsible people who would wish for the collapse of civilization suggests our times are no better than they were in 1935.