Yeah here's the thing. I *hate* cities. The noise, the crowding, the traffic, the lights, the endless stretches of asphalt and concrete. I don't even like visiting for more than a few hours. Overnight stay and I am done.
No problem, I can live rurally, right?
Well assume that a sizable portion of the population, say 20%, is like me (I think this is a generously low estimate given how many people choose to live rurally right now in developed countries, despite the "benefits" of cities). That's 20 billion people who want to live at a population density around 400/sqkm on average. You need 50 million sqkm to keep them comfortable and happy. Mind you most don't want to live in deserts or on glaciers.
This isn't going to happen. When it doesn't happen, you're going to get more conflict than you're expecting.
About 80% of people in advanced economies live in urban areas *today*. This goes up to 92% in Japan. These numbers keep growing.
A lot of the environment you like is defined by what you experience as a child, so it's reasonable to expect the number of children raised in cities to increase. My guess that will reach 90-95% That leaves just 5-10B people who want to live in more rural areas.
Today, there are 3.5B people living in rural areas, and most of countries like Russia, Canada, the US, Argentina, and Australia are basically empty. So you can easily get to 5B rural people, and probably 10B.
I think you're being overly optimistic. My view is it comes down to temperament, which isn't entirely environmental.
But either way population growth presumably doesn't stop at 100b in this scenario, so sooner or later you're going to run into this problem.
There is a carrying capacity beyond which it will become infeasible to host more people on earth. I've seen thermodynamic estimates of around 1-2 trillion (the point at which earth could no longer radiate away the waste heat generated by the population, assuming modest energy consumption and perfectly efficient heat loss). But long before we get there we'll have social conflicts.
You can't just say I'm too optimistic. You have to point out specifically the areas where I am being too optimistic, and why your assessment is different!
I agree there is a carrying capacity limit on Earth. My point is that it's orders of magnitude higher than what we think, and for all intents and purposes it's infinite for us. 100B or 1T or 10T is a theoretical debate. It will only become concrete in centuries, so let's let that debate to those people. They will have better tools to have it.
Well I did, I said I think it’s temperament, and that is not environmental, but I didn’t want to derail on a nature vs. nurture debate. Those are tedious. Just: this is why my POV is different.
And I agree with your general premise. Just think you’re being a little flippant about it. It will be a real challenge someday. But one of two things will happen: we will overcome it, or else we will reach the limit and nature will enforce it. Either way, fine.
And have absolutely no space grill food. You don't have to worry about getting to 100 billion people there's no way humans are gonna make it to 2035 hell it'll be a miracle if we make it to 2030. Your prop dribble is so pathetic, It's nothing more than tiny bit of humor. Well boatload of embarrassment and disappointment, from your mom.....
Most of the benefits you cite here in your first section are a result of technologies and some new social practices associated with industrialization. However, those technologies and social practices have now been invented and can be used henceforth -- like vaccines and antibiotics won't become uninvented if the world's population reverts back to the levels where they were originally invented. So the argument you're making is facile and doesn't do enough to disentangle different factors or explain how they may be organized in the future.
Also, there was WAY MORE foundational intellectual innovation in the world before the earth's population hit 2 billion. The intellectual advances of the last hundred years have largely been in engineering disciplines, not fundamental knowledge frameworks.
What is the threshold world population for maintaining a robust industrial base? If you can't give a number or a function based on resource factors (and I suspect nobody really can determine a definitive answer to this question at this time), you're just speculating. Which is fine (nothing wrong with speculating), but you're making these arguments with a level of unreasonable level of certainty.
These are complicated questions that require more than a short Substack post, if you're serious about understanding the reality of your topic.
1. Lots of knowledge lives in people's brains. If you don't have the people, you lose the tech.
2. Anitbiotic resistance is a thing. If we don't keep discovering new ones, we lose.
3. The benefits I mention are not the result of past inventions. They are an ongoing process. All the wealth we've created comes from these systems. We want them to keep going, not stop!
4. The was not more foundational intellectual innovation in the past. This is a common misconception that I will one day tackle. The short is: You're measuring it based on old disciplines. If you look at new ones, innovation is fine and well. AI is a perfect example.
5. The point of 100B is not literal. It's to say "Hey we have ample room between here and there".
6. Your question about maintaining a robust industrial base is off. This number has been calculated based on Mars colonization, and is about 1M people. But very few countries could achieve autarchy today (mybe US, Japan, SK), showing you'd probably need tens or hundreds of millions. Even then, that is assuming "keeping the existing user base". That's not the goal here. The goal is to maximize happiness, and what I'm saying is it's maximized with more people.
7. This is not a short substack post! And I've written 3 other articles about this already.
What does it mean to "maximize happiness"? That's a philosophical question, not something that can adequately be addressed with a few charts and graphs on social trends. What's more, it's largely a matter of values, and why should anyone reading this assume that your implicit values should be universally adopted -- particularly if you're not writing a long exegesis on those values as a focal topic, rather than gesturing at them by writing about population levels?
At what population thresholds do technologies like vaccines, antibiotics, solar panels, etc. start to experience serious attrition? It's okay not to know the answer, but the premise of your article is "anything less than current population levels would be a disaster and anything more than current levels will be amazing" and none of the information you've presented gives a definite answer to such threshold questions. If the Mars calculation you reference is something you believe, then I have trouble understanding why global population couldn't shrink by a half or a quarter and we couldn't still have a prosperous civilization; if it's not, what then? You could express uncertainty about these possibilities, while still raising your hypothesis, rather than hand-waving, you know.
We haven't been developing new antibiotics in recent decades because this work hasn't been economically incentivized. Adding more people to the planet isn't going to automatically change these incentives; it may even make it harder. Also, antibiotics lose their effectiveness the more they are deployed, so we're likely to cycle through medications more quickly when they are more people.
Since the 1920s, we've had one new foundational intellectual program that has received widespread research investment: information theory. All of the other advancements have been playing out stuff that was already conceived before the 1930s or achieving feats of engineering based on principles that were already established. Before this mark, there was the entire rest of the intellectual history of humanity, and, retrospectively, we take much of our inheritance for granted. Information theory has severe limitations as a fundamental framework, and we need a new intellectual revolution. It's the only way out of the reactionary muck that is overtaking our socio-political systems. But population levels alone aren't going to produce such new ideas: individuals have to do this.
1. This week's premium article is: Why Is It Moral to Want a Bigger Population
2. You might have thresholds for techs like solar, but then you hit other techs. Like fusion.
3. If you don't understand why a shrinking population would be bad, you should re-read the article! You lose all the reasons why our current system works, and get into a poor and conflict-ridden world!
4. Agreed on antibiotics
5. The Internet, drones, mobile, solar, batteries, X-rays, radar, healthcare, supersonic flight... The list is infinite
Sorry, I'm stingy about subscriptions, so I haven't read the paywalled article. It's another conversation -- but you understand that this is a contestable point, I take from this. I value the wild world as something that should be protected in part from human meddling, and I don't think every inch of the planet should be managed like the Netherlands. So, no, my values would prefer a minimum population that still retains the virtues of industrialization.
I agree that it won't be pleasant to have a shrinking population. But the longer term question isn't about the challenges that the next few generations face. It's about what kind of long term future do we want for humanity where industrialization is fully established as the cultural/civilizational norm? At some point we should want to hit a steady state (your article doesn't make the argument for 100 trillion humans on the earth, or is that where you think we should be headed?). There's a version of that steady state that is 1 billion, 2 billion, 8 billion, 50 billion, 100 billion, etc. What is the optimal number? What are theoretical minimums and maximums whereby the logic of industrialization completely falls apart? It would be more valuable to map out different long-term steady-state outcomes, as a matter of fundamental human values, than worrying about how trends are going to play out in the next century.
Industrialization is very very very new in human history, so I don't think these answers are clear. I suspect it won't be humans that determine this, ultimately. It will be the earth itself.
None of these things you mention are foundational intellectual advances. They're engineering projects. Newton's theory of gravity is a foundational advance. Sending a spaceship to the moon is an engineering feat. There hasn't been a foundational intellectual framework that has a widespread cultural effect since information theory started to congeal in the 1930s and 1940s. Everyone in the industrial world is living in the information theory paradigm right now, and we don't notice it because it sort of functions like intellectual oxygen for people who come up through conventional educational systems. This is why you think that engineering applications of foundational ideas ARE foundational ideas themselves; they're not. Only reactionaries are trying to escape this paradigm, for the most part, and they all suck as intellectuals, so their ideas are stupid and directed exclusively towards base emotions.
To quote Gretta Thunburg " fairytales of eternal economic growth." She's right on this hoping growth never ends is a bit of a fairytale. When you get to 100B you will only need more to support continued growth, exponentially more in fact. We are enjoying the good part of a pyramid scheme.
I've often said we are living in the best time in history and I still believe that. It's easy to demonstrate and I think you have helped my argument without repeating it. Those benefits of living in our time include more equality and freedom for women who are increasingly deciding not to have children. Anywhere in the world if you want to slow population or even create a decline just educate more women. Almost every country is trying to resolve this and the only success is accepting immigration from crowded poor countries they are trying to get out of.
The fairytale will remain a fairytale unless we have massive economic decline. When that happens people have less time for equality and social justice falls backwards, see election of Donald Trump after only a little decline.
I have looked into this data, and serious obstacle to terrestrial growth would only hit us in a few thousand years. So we shouldn't worry about that, because it's far away, and the people who will have to ponder that issue will know much more about the world at that time than we do.
The issue is that many people are trying to solve today a problem ("overpopulation") that we don't have today. We shouldn't do that! We have plenty of room to have more children now.
Hence why we should eliminate concerns that hinder fertility!
The concern that inhibits fertility is free choice for women. We don't want to hinder that. I really don't see anyone trying to slow population growth, much the opposite.
You do agree it's a pyramid scheme, just really far off so it's someone else's problem but there will be 1,000 billion by then? Passing on problems to future generations has been normal since we figured out how to turn fire into motion.
Hey, Tomas! I wanna say I've been following since 2022 and I absolutely adore Uncharted Territories. I've thought about commenting many times, but this is my first: you say a shrinking population would lead to lower GDP per Capita, but that's not what we're seeing in Romania and the Baltic states at all. They have been shrinking since the 90s and not only is everyone richer, the global GDP is higher as well. Now, I reckon that's because the cities themselves are growing while rural areas are becoming deserted, but still. Best wishes!
Romania is richer because of the EU and because it lives in a growing world. It uses catch up GDP growth piggybacking on the innovations and network effects of other places in the world.
Shrink the entire world, and you don’t get that benefit!
First, thanks for writing this, quite an exercise in visualization! It has challenged my outlook in a number of ways, whether I end up agreeing with you or not.
It seems to me that your argument relies on extrapolating a number of positive trends, without factoring in either diminishing returns or negative trends. An example of the former: we thought we were running out of lithium, but we just found a bunch more. That would have to happen times ten for all of the minerals we need to keep things running. And yes I know the trend has been less material per person, but still. An example of the latter: plastics, “forever” chemicals and a host of composites. Their use is trending up, and they seem inseparable from economic growth. You seem to wish their impact away with “technology! We’ll figure it out!” That’s a statement of faith, not based on any current trend. Same thing goes for extinction of species. Yes, species have come and gone, but not at this rate (except for mass extinctions which would likely wipe out humanity.
Great, I struggled for millennia to evolve from apes, making it through pandemics and medievalism, working in industrial sweatshops , surviving world wars and polyester suits in the 70s to what, live in giant apartments with millions of others in big cities? I'm not really into artificial environments, but that's me.
These thought exercises of imagining Earth with 100B or 2B humans are interesting but are very low-probability scenarios at least in the current century. The global population is expected to peak at around 10B at the end of the century and then likely decline. Given this prediction, I would like to read your thoughts about how we could continue progress and development without relying on population growth. I disagree that a declining or stable population will increase theft, corruption, war, inequality, cheating, and conflicts. There are ways of increasing productivity and growth without relying on more people by leveraging better technology including AI, robotics, and renewables, and by increasing average incomes.
It's not just theoretical, as I'll share in 2 days in the premium article. The belief that this isn't possible affects at least 25% of people who want to have children!
You disagree but don't point at why. I made my arguments, either break them or accept them. Otherwise, you hold your beliefs as dogma!
I'm not arguing that it isn't possible, I am saying that it is unlikely to happen given current birth rate trends, we are far more likely to peak at 10B than 100B.
GDP per capita does not have to shrink if the population stops growing. Income, spending, and investment can increase from new technology, better capital goods, and increased productivity. Deregulation particularly in areas like real estate and other overregulated industries can create growth. In the long term, extraterrestrial colonies can grow the economy and overall population by increasing trade.
There are countries today that have or will soon have declining populations and are still able to have a functioning society with a good quality of life even if they are growing slower than countries with faster population growth. Correlation is not causation. Just because population growth increased along with life expectancy, and less extreme poverty does not mean it caused these changes.
The point is that GDP per capita has grown at least partially through growth in humans. If you shrink instead of growing, suddenly you transform a tailwind into a headwind. You will be poorer than you would have been regardless. You bring up that maybe we are not poorer in absolute terms. Hopefully you're right. I read something about this. I should find it again.
Agreed that humans elsewhere is a good way to keep growing the economy. My point is not to say "OMG we absolutely need to superpopulate the Earth" but rather "Chill out, we can grow for centuries and still be fine".
The countries you mention (eg Japan) are doing OK (not great!) in part because the rest of the world keeps growing
Factor in global debt / QE and you'll see that GDP growth and human prosperity has been built on economic sand. About 80% of historical healthcare improvement and longevity is down to clean water, sanitation and vaccines. The rest is mainly treating diseases caused by the progress you're touting. You fail to mention the impact of religion on populations. Also, you conflate agricultural land use and the natural environment for feeding a city. City populations don't feed themselves. Finally, you fail to distinguish, contrast (or even mention) the urban sprawl of many major American cities, plus Tokyo and Moscow, with the less developed but high-density cities of Jakarta, Delhi, Manila, Mumbai, Mexico City, Cairo, Sao Paulo, Bangalore, Nairobi etc. The residents of the slums in the latter group could provide a better lesson in the future of any mass population growth or movement to megacities. The American decrease in longevity and Japanese, Russian, Italian, Polish etc decrease in fecundity are also trends that are dominating genuine demographics rather than anthropocentric utopian fantasies that seem born straight out of the late 1960s. We haven't walked on the moon for over half a century. Antibiotic resistance is increasing to lethal levels. The next influenza pandemic will make Covid seem like a picnic ('flu vaccines are typically only 40% effective). Humans don't live in a world disconnected from nature. Pollinator decline alone could starve us as a species. So a dose of realism would be very welcome.
If the population stops at 100 billion, it will have to slow down for a long time before that happens. Otherwise it will blow past that number and in a few decades there will be 200 billion. At some point it has to stop. You can't grow forever in a finite world.
I agree with your main point that humanity is nowhere near the planet’s carrying capacity, and that future declining population could turn out to be a big problem, but…
Would you settle for keeping world population steady at 8-10 billion people?
Given that this is going to be huge challenge in itself, I am not sure that shooting for 10X that level is a realistic or even desirable goal. It is not even clear how to maintain a 8 billion population given declining fertility rates.
It is also not clear the costs required to get to 100 billion population outweigh the benefits that you list.
For example, it is plausible to argue that 100 billion population is better than 10 billion, but the marginal investments required to get from 10 to 100 are more than the benefits of doing so. Many domains have diminishing returns.
Why settle if it’s strictly better to grow? No, I wouldn’t settle at that level.
Fertility is a different topic. Here, I cover whether we should. You ask whether we can. Another (very interesting and important) topic! But it’s a larger one. Here I wanted to narrowly cover this one aspect.
Thanks for the reply. I appreciate your effort to reply to comments. Not many writers do that.
As for your reply:
Fair enough, but I also question whether we should even try your goal when a more limited goal will be extremely difficult to achieve (avoiding declining global population).
Your argument seems to rely on humanity having knobs to turn to fine-tune the global population. I am not sure those knobs exist. And fertility is clearly a key knob.
Yes, my example is quite high level, but so is your goal.
Look, if you are just trying to kick off an interesting debate and get new readers, I have no problem with it, but if you are proposing a real goal then I think that you need to consider the costs and benefits of both the end (100 billion) and the means to get there (which are unknown).
I would suggest that the person making the proposal should do the ROI, not the skeptics.
Doesn’t cost of transportation in cities scale faster than linear? The amount of people to be transported scales linear, but in a bigger city those people will want to travel (1) further away, and (2) faster. Meanwhile land gets more expensive.
Anyway, the big problem we have to solve in this scenario, is will we muster the willpower to create actual *human* habitat in cities? Most cities today aren't habitat for humans, they're habitat for *cars*. I can go out on my street, right now †, and make a 360° panorama without a single human being in view.
Those cars are basically today’s equivalent of the sewerage problem of cast century. Why do people hate cities:
– Cities are loud → it is the cars (including electric cars, it is mostly tyre noise in most places)
– Cities are dangerous → it is the cars.
– Cities are soul-destroyingly ugly → it is the huge roadways and parking.
– Cities are crowded → there is no room because almost all public spaces are occupied with roadways and parking
– Apartments are suffocating → see previous point
– You can’t live there with kids → see previous point
– Cities are polluted → we got the industry out of our inner cities, only to get cars in a few decades later. (even with electric cars there are things like tyre wear and road surface wear)
Of course cars are useful, but there is such thing as overdoing it. Cars also scale up pretty poorly in large cities. In essence most of the above are negative externalities to driving that are currently mostly not priced. So we have way more cars than optimal.
What cities look like if we optimize the number of cars, I don’t know, I never experienced such a city. But chances are we'll find much more volunteers to live in dense cities.
That “essence of Paris” is something that should be normal, and ideally within walking distance of almost everyone in cities. There are not many cars in that picture. Observe how this is possible even with merely our current level of technology.
And keeping within the theme of this series, having people live in big cities, and still having kids is, ahem, uncharted territory in many countries. This will also almost certainly improve if we think more consciously of cities as human habitat.
There are other problems too, of course. In many cities it seems barely possible to keep shops open at all because crime is so bad. In others (even huge ones) shops can just display their wares out on the street for passers by to have a look. Why is that. We’ll want cities to become much more like that second one.
But I don't think this a problem of going from 8B to 100B. It's a problem *today*! We could make such better cities—and I argue Europeans and Asians do a better job at this than Americans. Many city centers are car-free, and they're lovely.
This is an issue of urban planning, and how influences like Le Corbusier destroyed it. We need a better urbanism for the 21st century, I'm all for it!
I agree with your point that the drop in fertility in urban areas is probably partially caused by the issues you highlight.
What scales up in big cities is not cars, but public transportation.
Yes. And there are many signs to be optimistic about this. Tokyo already exists. Paris is taking measures to create better spaces for people in ways that were unthinkable 5 years ago. The architecture profession basically self-immolated in the second half of last century (is there even a single person alive who likes International Style?), but it seems to be recovering. And the actual revolution in electric transportation is electric bikes (missed opportunity for Tesla there).
Interesting ! I have one question and one remark :
- Do you think a world with a shrinking population (which is probably what's gonna happen at some point) would call into the question the paradigm of economic growth ? Basically : for now, investing in ETFs betting on the global economy to keep growing long term is a pretty safe bet, but what if population dwindles ? My instinct is we don't know yet if it'll be compensated by other factors, but I'd be curious about your take on this.
- I think it's a bit naive to think city life would be good in those conditions. It's already bad today. It's noisy, traffic is hell, public transportation is only barely okay in very big cities (and not good enough considering the amount of money spent), and most people spend a LOT of time commuting. Big cities today are good only if you have money.
For example, I'd love to live in NYC, but I estimate to have a good quality of life I'd need to have millions in capital.
I don't see how growing the cities bigger is not gonna make that worse.
The thing is : I can imagine cities which are way better to live in, way more efficient, but that requires such changes to society as a whole, and we're obviously struggling so much with less of a challenge now, that I don't think it's realistic to think it'd happen.
That being said, even though I get some of your points, I don't think we're gonna get to 100B anyway.
1. Yes, a shrinking world is one where stocks likely shrink, along with every other investment. No investment is safe! And I think we're going to start feeling this in the West, which is why I wrote this:
2. Traffic noise will disappear thanks to electric cars
Congestion will be reduced thanks to self-driving cars, buses, and probably underground that is much faster thanks to tech like the Boring Company.
Lots of commute becomes unnecessary through remote
There are literally a hundred ways in which all these problems will be resolved by tech, a lot of which is not even in 100 years, but just around the corner! Don't make the mistake to project the problems but not the solutions
3. Fun fact: Did you know the number of homes and people in Manhattan has *shrunk* in the last century? How crazy is that!
There's plenty we could do with Manhattan. But it's pretty dense already. If there were many more Manhattans in the world, you wouldn't need to go to THAT one!
4. We don't need to get to 100B. I just want to convey the point that *we, our children, and our grandchildren can grow as much as we want and that will cause no problem at all!*
A number of the economic benefits you cite rely not just on large population but on growing population. Whether the limit is 100B or somewhere else, there's going to be a point where growth reaches a limit, so future humans have to develop economic and other systems that allow prosperity in steady-state population (likely depending on tech improvements)
Also to note that a balance needs to be found between wealth growth and population growth, as due to current cultural norms and economic incentives, more wealth leads to lower birthrate. For 100B (or anything over 10B really), that relationship has got to be broken
I think that he is saying that it is better to “ develop economic and other systems that allow prosperity in steady-state population” than to try to increase population ten-fold.
Those are two different goals that likely conflict, so diverting resources to one leaves fewer resources for the other goal.
"So historically, the amount of people and happiness have grown together. Therefore, the safest prediction is to assume this will continue: Overall, we will be better off in the future."
You offered me such a laugh, thanks for that.
The issue or crux of the matter is not the number of people, but rather the way they/we inhabit our only planet, whose limits and capabilities to mitigate our impacts are getting smaller and smaller (do us a favour, read the following US version of the "World without end" comic book by Jancovici & Blain).
Someone wiser than me, rightly said: we have divine (tech and fossil-based) powers, but a medieval global governance and still mainly a prehistoric brain...
Please put your article on Earth carrying capacity in the free domain so that it can be properly debated. I cannot bring forward any argument without understanding yours (and debating them with more people...)
In Italy we are currently 60 mio people: in your opinion, if you distribute evenly a 12.5 fold increase in population, we should have 750 million people, with a mean (even on the top of the Alps) density of 2,450 souls per squared km. I'm sorry to tell you that you are completely out of your mind, no offense, but i'm fed up of reading such anti-scientific nonsense. Your article is good only for a distopic sci-fi novel.
I don't think he assumes all Italians stay in Italy or anything like that. I suppose some Italian cities would grow severalfold (they can do that), and people would move around, finding less populated places if they wish, e.g., northern Scandinavia. The bigger problem is the folks who prefer countryside to city life, like the commenter above; if there's a large percentage of those, they won't have enough opportunities.
Yeah here's the thing. I *hate* cities. The noise, the crowding, the traffic, the lights, the endless stretches of asphalt and concrete. I don't even like visiting for more than a few hours. Overnight stay and I am done.
No problem, I can live rurally, right?
Well assume that a sizable portion of the population, say 20%, is like me (I think this is a generously low estimate given how many people choose to live rurally right now in developed countries, despite the "benefits" of cities). That's 20 billion people who want to live at a population density around 400/sqkm on average. You need 50 million sqkm to keep them comfortable and happy. Mind you most don't want to live in deserts or on glaciers.
This isn't going to happen. When it doesn't happen, you're going to get more conflict than you're expecting.
It's not this simple.
OK I hear you. Let's break down this logic.
About 80% of people in advanced economies live in urban areas *today*. This goes up to 92% in Japan. These numbers keep growing.
A lot of the environment you like is defined by what you experience as a child, so it's reasonable to expect the number of children raised in cities to increase. My guess that will reach 90-95% That leaves just 5-10B people who want to live in more rural areas.
Today, there are 3.5B people living in rural areas, and most of countries like Russia, Canada, the US, Argentina, and Australia are basically empty. So you can easily get to 5B rural people, and probably 10B.
I think you're being overly optimistic. My view is it comes down to temperament, which isn't entirely environmental.
But either way population growth presumably doesn't stop at 100b in this scenario, so sooner or later you're going to run into this problem.
There is a carrying capacity beyond which it will become infeasible to host more people on earth. I've seen thermodynamic estimates of around 1-2 trillion (the point at which earth could no longer radiate away the waste heat generated by the population, assuming modest energy consumption and perfectly efficient heat loss). But long before we get there we'll have social conflicts.
Fortunately there's a lot of space ... In space.
You can't just say I'm too optimistic. You have to point out specifically the areas where I am being too optimistic, and why your assessment is different!
I agree there is a carrying capacity limit on Earth. My point is that it's orders of magnitude higher than what we think, and for all intents and purposes it's infinite for us. 100B or 1T or 10T is a theoretical debate. It will only become concrete in centuries, so let's let that debate to those people. They will have better tools to have it.
Well I did, I said I think it’s temperament, and that is not environmental, but I didn’t want to derail on a nature vs. nurture debate. Those are tedious. Just: this is why my POV is different.
And I agree with your general premise. Just think you’re being a little flippant about it. It will be a real challenge someday. But one of two things will happen: we will overcome it, or else we will reach the limit and nature will enforce it. Either way, fine.
And have absolutely no space grill food. You don't have to worry about getting to 100 billion people there's no way humans are gonna make it to 2035 hell it'll be a miracle if we make it to 2030. Your prop dribble is so pathetic, It's nothing more than tiny bit of humor. Well boatload of embarrassment and disappointment, from your mom.....
Maybe I miss something here. This is satire, right?
Most of the benefits you cite here in your first section are a result of technologies and some new social practices associated with industrialization. However, those technologies and social practices have now been invented and can be used henceforth -- like vaccines and antibiotics won't become uninvented if the world's population reverts back to the levels where they were originally invented. So the argument you're making is facile and doesn't do enough to disentangle different factors or explain how they may be organized in the future.
Also, there was WAY MORE foundational intellectual innovation in the world before the earth's population hit 2 billion. The intellectual advances of the last hundred years have largely been in engineering disciplines, not fundamental knowledge frameworks.
What is the threshold world population for maintaining a robust industrial base? If you can't give a number or a function based on resource factors (and I suspect nobody really can determine a definitive answer to this question at this time), you're just speculating. Which is fine (nothing wrong with speculating), but you're making these arguments with a level of unreasonable level of certainty.
These are complicated questions that require more than a short Substack post, if you're serious about understanding the reality of your topic.
Yes and no.
1. Lots of knowledge lives in people's brains. If you don't have the people, you lose the tech.
2. Anitbiotic resistance is a thing. If we don't keep discovering new ones, we lose.
3. The benefits I mention are not the result of past inventions. They are an ongoing process. All the wealth we've created comes from these systems. We want them to keep going, not stop!
4. The was not more foundational intellectual innovation in the past. This is a common misconception that I will one day tackle. The short is: You're measuring it based on old disciplines. If you look at new ones, innovation is fine and well. AI is a perfect example.
5. The point of 100B is not literal. It's to say "Hey we have ample room between here and there".
6. Your question about maintaining a robust industrial base is off. This number has been calculated based on Mars colonization, and is about 1M people. But very few countries could achieve autarchy today (mybe US, Japan, SK), showing you'd probably need tens or hundreds of millions. Even then, that is assuming "keeping the existing user base". That's not the goal here. The goal is to maximize happiness, and what I'm saying is it's maximized with more people.
7. This is not a short substack post! And I've written 3 other articles about this already.
What does it mean to "maximize happiness"? That's a philosophical question, not something that can adequately be addressed with a few charts and graphs on social trends. What's more, it's largely a matter of values, and why should anyone reading this assume that your implicit values should be universally adopted -- particularly if you're not writing a long exegesis on those values as a focal topic, rather than gesturing at them by writing about population levels?
At what population thresholds do technologies like vaccines, antibiotics, solar panels, etc. start to experience serious attrition? It's okay not to know the answer, but the premise of your article is "anything less than current population levels would be a disaster and anything more than current levels will be amazing" and none of the information you've presented gives a definite answer to such threshold questions. If the Mars calculation you reference is something you believe, then I have trouble understanding why global population couldn't shrink by a half or a quarter and we couldn't still have a prosperous civilization; if it's not, what then? You could express uncertainty about these possibilities, while still raising your hypothesis, rather than hand-waving, you know.
We haven't been developing new antibiotics in recent decades because this work hasn't been economically incentivized. Adding more people to the planet isn't going to automatically change these incentives; it may even make it harder. Also, antibiotics lose their effectiveness the more they are deployed, so we're likely to cycle through medications more quickly when they are more people.
Since the 1920s, we've had one new foundational intellectual program that has received widespread research investment: information theory. All of the other advancements have been playing out stuff that was already conceived before the 1930s or achieving feats of engineering based on principles that were already established. Before this mark, there was the entire rest of the intellectual history of humanity, and, retrospectively, we take much of our inheritance for granted. Information theory has severe limitations as a fundamental framework, and we need a new intellectual revolution. It's the only way out of the reactionary muck that is overtaking our socio-political systems. But population levels alone aren't going to produce such new ideas: individuals have to do this.
1. This week's premium article is: Why Is It Moral to Want a Bigger Population
2. You might have thresholds for techs like solar, but then you hit other techs. Like fusion.
3. If you don't understand why a shrinking population would be bad, you should re-read the article! You lose all the reasons why our current system works, and get into a poor and conflict-ridden world!
4. Agreed on antibiotics
5. The Internet, drones, mobile, solar, batteries, X-rays, radar, healthcare, supersonic flight... The list is infinite
Sorry, I'm stingy about subscriptions, so I haven't read the paywalled article. It's another conversation -- but you understand that this is a contestable point, I take from this. I value the wild world as something that should be protected in part from human meddling, and I don't think every inch of the planet should be managed like the Netherlands. So, no, my values would prefer a minimum population that still retains the virtues of industrialization.
I agree that it won't be pleasant to have a shrinking population. But the longer term question isn't about the challenges that the next few generations face. It's about what kind of long term future do we want for humanity where industrialization is fully established as the cultural/civilizational norm? At some point we should want to hit a steady state (your article doesn't make the argument for 100 trillion humans on the earth, or is that where you think we should be headed?). There's a version of that steady state that is 1 billion, 2 billion, 8 billion, 50 billion, 100 billion, etc. What is the optimal number? What are theoretical minimums and maximums whereby the logic of industrialization completely falls apart? It would be more valuable to map out different long-term steady-state outcomes, as a matter of fundamental human values, than worrying about how trends are going to play out in the next century.
Industrialization is very very very new in human history, so I don't think these answers are clear. I suspect it won't be humans that determine this, ultimately. It will be the earth itself.
None of these things you mention are foundational intellectual advances. They're engineering projects. Newton's theory of gravity is a foundational advance. Sending a spaceship to the moon is an engineering feat. There hasn't been a foundational intellectual framework that has a widespread cultural effect since information theory started to congeal in the 1930s and 1940s. Everyone in the industrial world is living in the information theory paradigm right now, and we don't notice it because it sort of functions like intellectual oxygen for people who come up through conventional educational systems. This is why you think that engineering applications of foundational ideas ARE foundational ideas themselves; they're not. Only reactionaries are trying to escape this paradigm, for the most part, and they all suck as intellectuals, so their ideas are stupid and directed exclusively towards base emotions.
I guess you'll have to read it!
To quote Gretta Thunburg " fairytales of eternal economic growth." She's right on this hoping growth never ends is a bit of a fairytale. When you get to 100B you will only need more to support continued growth, exponentially more in fact. We are enjoying the good part of a pyramid scheme.
I've often said we are living in the best time in history and I still believe that. It's easy to demonstrate and I think you have helped my argument without repeating it. Those benefits of living in our time include more equality and freedom for women who are increasingly deciding not to have children. Anywhere in the world if you want to slow population or even create a decline just educate more women. Almost every country is trying to resolve this and the only success is accepting immigration from crowded poor countries they are trying to get out of.
The fairytale will remain a fairytale unless we have massive economic decline. When that happens people have less time for equality and social justice falls backwards, see election of Donald Trump after only a little decline.
I have looked into this data, and serious obstacle to terrestrial growth would only hit us in a few thousand years. So we shouldn't worry about that, because it's far away, and the people who will have to ponder that issue will know much more about the world at that time than we do.
The issue is that many people are trying to solve today a problem ("overpopulation") that we don't have today. We shouldn't do that! We have plenty of room to have more children now.
Hence why we should eliminate concerns that hinder fertility!
The concern that inhibits fertility is free choice for women. We don't want to hinder that. I really don't see anyone trying to slow population growth, much the opposite.
You do agree it's a pyramid scheme, just really far off so it's someone else's problem but there will be 1,000 billion by then? Passing on problems to future generations has been normal since we figured out how to turn fire into motion.
Hey, Tomas! I wanna say I've been following since 2022 and I absolutely adore Uncharted Territories. I've thought about commenting many times, but this is my first: you say a shrinking population would lead to lower GDP per Capita, but that's not what we're seeing in Romania and the Baltic states at all. They have been shrinking since the 90s and not only is everyone richer, the global GDP is higher as well. Now, I reckon that's because the cities themselves are growing while rural areas are becoming deserted, but still. Best wishes!
Thanks Pedro! Feel free to comment at will!
Romania is richer because of the EU and because it lives in a growing world. It uses catch up GDP growth piggybacking on the innovations and network effects of other places in the world.
Shrink the entire world, and you don’t get that benefit!
We will need a bigger Santiago Bernabeu Stadium so that all those people can go to enjoy Real Madrid matches 😅.
Congrats for this serial, Tomás, it has been a great pleasure to read the articles and connect growth population with humanism.
Or VR will enable us to feel like we're there!
Or maybe the game will be projected across stadiums around the world in real time so you feel like you're there
Let's not seel technology short!
First, thanks for writing this, quite an exercise in visualization! It has challenged my outlook in a number of ways, whether I end up agreeing with you or not.
It seems to me that your argument relies on extrapolating a number of positive trends, without factoring in either diminishing returns or negative trends. An example of the former: we thought we were running out of lithium, but we just found a bunch more. That would have to happen times ten for all of the minerals we need to keep things running. And yes I know the trend has been less material per person, but still. An example of the latter: plastics, “forever” chemicals and a host of composites. Their use is trending up, and they seem inseparable from economic growth. You seem to wish their impact away with “technology! We’ll figure it out!” That’s a statement of faith, not based on any current trend. Same thing goes for extinction of species. Yes, species have come and gone, but not at this rate (except for mass extinctions which would likely wipe out humanity.
I’d love to have a cup of coffee some time…
This was like a chiropractic adjustment for my mind in that it’s really depressing to think about the world in terms of less humans = good.
People who say they don’t want to have children for the environment always bum me out and make me second guess whether wanting kids is selfish.
It’s really a relief to see the upside of more people!
Time to make babies and feel good about it!
This week’s premium article goes further: it’s actually the ethical thing to want a more populated world!
Great, I struggled for millennia to evolve from apes, making it through pandemics and medievalism, working in industrial sweatshops , surviving world wars and polyester suits in the 70s to what, live in giant apartments with millions of others in big cities? I'm not really into artificial environments, but that's me.
There will be room for you!
These thought exercises of imagining Earth with 100B or 2B humans are interesting but are very low-probability scenarios at least in the current century. The global population is expected to peak at around 10B at the end of the century and then likely decline. Given this prediction, I would like to read your thoughts about how we could continue progress and development without relying on population growth. I disagree that a declining or stable population will increase theft, corruption, war, inequality, cheating, and conflicts. There are ways of increasing productivity and growth without relying on more people by leveraging better technology including AI, robotics, and renewables, and by increasing average incomes.
It's not just theoretical, as I'll share in 2 days in the premium article. The belief that this isn't possible affects at least 25% of people who want to have children!
You disagree but don't point at why. I made my arguments, either break them or accept them. Otherwise, you hold your beliefs as dogma!
I'm not arguing that it isn't possible, I am saying that it is unlikely to happen given current birth rate trends, we are far more likely to peak at 10B than 100B.
GDP per capita does not have to shrink if the population stops growing. Income, spending, and investment can increase from new technology, better capital goods, and increased productivity. Deregulation particularly in areas like real estate and other overregulated industries can create growth. In the long term, extraterrestrial colonies can grow the economy and overall population by increasing trade.
There are countries today that have or will soon have declining populations and are still able to have a functioning society with a good quality of life even if they are growing slower than countries with faster population growth. Correlation is not causation. Just because population growth increased along with life expectancy, and less extreme poverty does not mean it caused these changes.
The point is that GDP per capita has grown at least partially through growth in humans. If you shrink instead of growing, suddenly you transform a tailwind into a headwind. You will be poorer than you would have been regardless. You bring up that maybe we are not poorer in absolute terms. Hopefully you're right. I read something about this. I should find it again.
Agreed that humans elsewhere is a good way to keep growing the economy. My point is not to say "OMG we absolutely need to superpopulate the Earth" but rather "Chill out, we can grow for centuries and still be fine".
The countries you mention (eg Japan) are doing OK (not great!) in part because the rest of the world keeps growing
Factor in global debt / QE and you'll see that GDP growth and human prosperity has been built on economic sand. About 80% of historical healthcare improvement and longevity is down to clean water, sanitation and vaccines. The rest is mainly treating diseases caused by the progress you're touting. You fail to mention the impact of religion on populations. Also, you conflate agricultural land use and the natural environment for feeding a city. City populations don't feed themselves. Finally, you fail to distinguish, contrast (or even mention) the urban sprawl of many major American cities, plus Tokyo and Moscow, with the less developed but high-density cities of Jakarta, Delhi, Manila, Mumbai, Mexico City, Cairo, Sao Paulo, Bangalore, Nairobi etc. The residents of the slums in the latter group could provide a better lesson in the future of any mass population growth or movement to megacities. The American decrease in longevity and Japanese, Russian, Italian, Polish etc decrease in fecundity are also trends that are dominating genuine demographics rather than anthropocentric utopian fantasies that seem born straight out of the late 1960s. We haven't walked on the moon for over half a century. Antibiotic resistance is increasing to lethal levels. The next influenza pandemic will make Covid seem like a picnic ('flu vaccines are typically only 40% effective). Humans don't live in a world disconnected from nature. Pollinator decline alone could starve us as a species. So a dose of realism would be very welcome.
If the population stops at 100 billion, it will have to slow down for a long time before that happens. Otherwise it will blow past that number and in a few decades there will be 200 billion. At some point it has to stop. You can't grow forever in a finite world.
I agree with your main point that humanity is nowhere near the planet’s carrying capacity, and that future declining population could turn out to be a big problem, but…
Would you settle for keeping world population steady at 8-10 billion people?
Given that this is going to be huge challenge in itself, I am not sure that shooting for 10X that level is a realistic or even desirable goal. It is not even clear how to maintain a 8 billion population given declining fertility rates.
It is also not clear the costs required to get to 100 billion population outweigh the benefits that you list.
For example, it is plausible to argue that 100 billion population is better than 10 billion, but the marginal investments required to get from 10 to 100 are more than the benefits of doing so. Many domains have diminishing returns.
Why settle if it’s strictly better to grow? No, I wouldn’t settle at that level.
Fertility is a different topic. Here, I cover whether we should. You ask whether we can. Another (very interesting and important) topic! But it’s a larger one. Here I wanted to narrowly cover this one aspect.
If you have a different ROI analysis LMK!
Your example is quite high level.
Thanks for the reply. I appreciate your effort to reply to comments. Not many writers do that.
As for your reply:
Fair enough, but I also question whether we should even try your goal when a more limited goal will be extremely difficult to achieve (avoiding declining global population).
Your argument seems to rely on humanity having knobs to turn to fine-tune the global population. I am not sure those knobs exist. And fertility is clearly a key knob.
Yes, my example is quite high level, but so is your goal.
Look, if you are just trying to kick off an interesting debate and get new readers, I have no problem with it, but if you are proposing a real goal then I think that you need to consider the costs and benefits of both the end (100 billion) and the means to get there (which are unknown).
I would suggest that the person making the proposal should do the ROI, not the skeptics.
Doesn’t cost of transportation in cities scale faster than linear? The amount of people to be transported scales linear, but in a bigger city those people will want to travel (1) further away, and (2) faster. Meanwhile land gets more expensive.
Anyway, the big problem we have to solve in this scenario, is will we muster the willpower to create actual *human* habitat in cities? Most cities today aren't habitat for humans, they're habitat for *cars*. I can go out on my street, right now †, and make a 360° panorama without a single human being in view.
Those cars are basically today’s equivalent of the sewerage problem of cast century. Why do people hate cities:
– Cities are loud → it is the cars (including electric cars, it is mostly tyre noise in most places)
– Cities are dangerous → it is the cars.
– Cities are soul-destroyingly ugly → it is the huge roadways and parking.
– Cities are crowded → there is no room because almost all public spaces are occupied with roadways and parking
– Apartments are suffocating → see previous point
– You can’t live there with kids → see previous point
– Cities are polluted → we got the industry out of our inner cities, only to get cars in a few decades later. (even with electric cars there are things like tyre wear and road surface wear)
Of course cars are useful, but there is such thing as overdoing it. Cars also scale up pretty poorly in large cities. In essence most of the above are negative externalities to driving that are currently mostly not priced. So we have way more cars than optimal.
What cities look like if we optimize the number of cars, I don’t know, I never experienced such a city. But chances are we'll find much more volunteers to live in dense cities.
That “essence of Paris” is something that should be normal, and ideally within walking distance of almost everyone in cities. There are not many cars in that picture. Observe how this is possible even with merely our current level of technology.
And keeping within the theme of this series, having people live in big cities, and still having kids is, ahem, uncharted territory in many countries. This will also almost certainly improve if we think more consciously of cities as human habitat.
There are other problems too, of course. In many cities it seems barely possible to keep shops open at all because crime is so bad. In others (even huge ones) shops can just display their wares out on the street for passers by to have a look. Why is that. We’ll want cities to become much more like that second one.
—
† it is daytime
I agree!
But I don't think this a problem of going from 8B to 100B. It's a problem *today*! We could make such better cities—and I argue Europeans and Asians do a better job at this than Americans. Many city centers are car-free, and they're lovely.
This is an issue of urban planning, and how influences like Le Corbusier destroyed it. We need a better urbanism for the 21st century, I'm all for it!
I agree with your point that the drop in fertility in urban areas is probably partially caused by the issues you highlight.
What scales up in big cities is not cars, but public transportation.
Yes. And there are many signs to be optimistic about this. Tokyo already exists. Paris is taking measures to create better spaces for people in ways that were unthinkable 5 years ago. The architecture profession basically self-immolated in the second half of last century (is there even a single person alive who likes International Style?), but it seems to be recovering. And the actual revolution in electric transportation is electric bikes (missed opportunity for Tesla there).
Interesting ! I have one question and one remark :
- Do you think a world with a shrinking population (which is probably what's gonna happen at some point) would call into the question the paradigm of economic growth ? Basically : for now, investing in ETFs betting on the global economy to keep growing long term is a pretty safe bet, but what if population dwindles ? My instinct is we don't know yet if it'll be compensated by other factors, but I'd be curious about your take on this.
- I think it's a bit naive to think city life would be good in those conditions. It's already bad today. It's noisy, traffic is hell, public transportation is only barely okay in very big cities (and not good enough considering the amount of money spent), and most people spend a LOT of time commuting. Big cities today are good only if you have money.
For example, I'd love to live in NYC, but I estimate to have a good quality of life I'd need to have millions in capital.
I don't see how growing the cities bigger is not gonna make that worse.
The thing is : I can imagine cities which are way better to live in, way more efficient, but that requires such changes to society as a whole, and we're obviously struggling so much with less of a challenge now, that I don't think it's realistic to think it'd happen.
That being said, even though I get some of your points, I don't think we're gonna get to 100B anyway.
1. Yes, a shrinking world is one where stocks likely shrink, along with every other investment. No investment is safe! And I think we're going to start feeling this in the West, which is why I wrote this:
https://unchartedterritories.tomaspueyo.com/p/why-i-dont-invest-in-real-estate
2. Traffic noise will disappear thanks to electric cars
Congestion will be reduced thanks to self-driving cars, buses, and probably underground that is much faster thanks to tech like the Boring Company.
Lots of commute becomes unnecessary through remote
There are literally a hundred ways in which all these problems will be resolved by tech, a lot of which is not even in 100 years, but just around the corner! Don't make the mistake to project the problems but not the solutions
3. Fun fact: Did you know the number of homes and people in Manhattan has *shrunk* in the last century? How crazy is that!
https://urbanomnibus.net/2014/10/the-rise-and-fall-of-manhattans-density/
There's plenty we could do with Manhattan. But it's pretty dense already. If there were many more Manhattans in the world, you wouldn't need to go to THAT one!
4. We don't need to get to 100B. I just want to convey the point that *we, our children, and our grandchildren can grow as much as we want and that will cause no problem at all!*
Most traffic noise comes from tyres, so it will be roughly the same with electric cars.
Not at the speeds we're talking about! Listen!
https://www.tiktok.com/@fcohen/video/7312417846120697130?lang=en
A number of the economic benefits you cite rely not just on large population but on growing population. Whether the limit is 100B or somewhere else, there's going to be a point where growth reaches a limit, so future humans have to develop economic and other systems that allow prosperity in steady-state population (likely depending on tech improvements)
Also to note that a balance needs to be found between wealth growth and population growth, as due to current cultural norms and economic incentives, more wealth leads to lower birthrate. For 100B (or anything over 10B really), that relationship has got to be broken
Yes indeed! I don't believe in infinite growth. But that's a problem for the 24th century. We should not worry about this now! We have ample margin!
Wealth is not the primary driver of fertility! As of today, in many developed countries, the wealthier strata have more children!
I think that he is saying that it is better to “ develop economic and other systems that allow prosperity in steady-state population” than to try to increase population ten-fold.
Those are two different goals that likely conflict, so diverting resources to one leaves fewer resources for the other goal.
Tomas, are you energy blind?
"So historically, the amount of people and happiness have grown together. Therefore, the safest prediction is to assume this will continue: Overall, we will be better off in the future."
You offered me such a laugh, thanks for that.
The issue or crux of the matter is not the number of people, but rather the way they/we inhabit our only planet, whose limits and capabilities to mitigate our impacts are getting smaller and smaller (do us a favour, read the following US version of the "World without end" comic book by Jancovici & Blain).
Someone wiser than me, rightly said: we have divine (tech and fossil-based) powers, but a medieval global governance and still mainly a prehistoric brain...
I'm not sure what your argument is. I have Jancovici's book but haven't read it, so I will.
Agreed on the governance issue.
Energy is not a problem!
https://unchartedterritories.tomaspueyo.com/p/100-billion-humans
Please put your article on Earth carrying capacity in the free domain so that it can be properly debated. I cannot bring forward any argument without understanding yours (and debating them with more people...)
In Italy we are currently 60 mio people: in your opinion, if you distribute evenly a 12.5 fold increase in population, we should have 750 million people, with a mean (even on the top of the Alps) density of 2,450 souls per squared km. I'm sorry to tell you that you are completely out of your mind, no offense, but i'm fed up of reading such anti-scientific nonsense. Your article is good only for a distopic sci-fi novel.
I don't think he assumes all Italians stay in Italy or anything like that. I suppose some Italian cities would grow severalfold (they can do that), and people would move around, finding less populated places if they wish, e.g., northern Scandinavia. The bigger problem is the folks who prefer countryside to city life, like the commenter above; if there's a large percentage of those, they won't have enough opportunities.
Italy has a high population density. It would not 12x its population!
Back of the envelope, you need 700-1000 ppl/km2. That would mean multiplying Italy's pop density by ~4.
That can be achieved simply by doubling the current cities' radius, that's it.