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.
At least in the US, more than twice as many “urban” residents actually live in suburbs and exurbs as live in the actual city. I technically am in an MSA. There are horses, cattle, goats, and sheep living on my road, and the smallest lots are 2 acres - largest are in the hundreds of acres. Your urban 80% includes millions of people living in similar areas.
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.....
Relevantly to growing the world's population to 100B, most young children and parents of young children also hate living in cities.
Kids can't do developmentally important things like playing in dirt or running around outside with light supervision in a city. They'll get lead poisoning or get hit by a car. Most parents realize this and move to the suburbs or country where their kids can have a more human life. Some stay in the city but find raising kids there so difficult/unhappy that they stop after one or two.
Throughout history, cities have typically had a below replacement fertility rate. They're playgrounds for perpetually childfree adults, or networking hubs for young people to get established in their careers before they settle down elsewhere. Cities have always been reliant on a steady infusion of population from more vital areas. One might even argue that urbanization is the primary cause of the fertility collapse.
Whatever percentage of people would be happy living in Paris-like conditions, the number will be lower if they have the needs of a family in mind.
Suburbs and rural areas aren't perfect either, but they're better for families than Paris is. Still, there are many ways suburbs and urban areas like Paris could be made more family friendly. Primarily, there need to be larger (shared when necessary) green spaces that are fenced or in an apartment courtyard. A 4yo should be able to come and go outside without danger of cars while their parent watches them occasionally from the ground floor of their home. And those homes need to be big enough for a family of 5+ and affordable enough to live on a single income, if families are to be able to focus on having the kids and family life that most people want. Probably one of the only ways to get to 100B would be to guarantee families homes at least that appropriate.
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
You have not made your argument. There is no reason to believe that shrinking population would decrease GDP per capita, and powerful arguments that it would not.
What you are describing is a crowded dystopian hellscape, not a paradise.
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.
Your replies in this thread point into other direction - unsubscribe and never come back here. Your lack of willingness to engage with a reasonable arguments and desire to push your content and values without solid backup are pathetic.
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.
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.
Free choice is not the problem. For starters, it doesn't truly exist. Also, it's heavily influenced by external factors, like culture and economics. Finally, the actual number of children is lower than the desired number, as I explain!
Free choice is not a problem! That should be clear but not all the world agrees. There might be too few children for you but you need at least one woman to agree with you.
According to the actual data on growth and overshoot, we peaked already not due to population density but due to the resources ot takes to keep this level of civilization running as it is. Land isn't an issue, farmland is. You can't just say you did research and not back it up.
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.
Interesting as always Tomas. You're taking a very Panglossian view in these articles. I think you overestimate the ability of technology to "fix" problems and underestimate the impact of environmental, economic, and social constraints. Desalination holds much potential, but to do this at a scale sufficient and rapid enough to compensate for the accelerating depletion of fresh water sources will be economically prohibitive for much of the world. Similar consideration applies to global warming. Even assuming the transition to renewable energy imcreases in scale and speed, there is hysteresis in levels of greenhouse gases in the atmosphere and ocean acidification. If the world stopped using fossil fuels tomorrow, these gases would remain at high levels for some years, and the extreme weather impacts we're experiencing would persist. We know that fossil fuel use will continue for years to come, especially if Trump has his way. Parts of the world are approaching temperatures that will make them uninhabitable for much of the year. Another factor is whether economic systems can sustain 100B people. Seems that increasing numbers of economists are concluding that neoliberal capitalism is a failure because it transfers wealth upward and leaves others worse off than they were before Clinton era. The current gross levels of wealth inequality are unsustainable and one could interpret the 2024 election as an expression of widespread anger about the staus quo. I find it hard to envision large increases in population in the absence of radical economic changes. Not going to hold my breath for that. Finally you seem to assume that there is a linear increase in creativity and innovation with population. But I doubt that's true, judging by my 70 years of interaction with people. Sorry to go on so long. You raised so may interesting questions!
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.
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!
I agree that human population growth can allow increasing specialization, all else equal. However, it is a mistake to assume that human knowledge exists in human memory. Scientists and researchers commit information to knowledge bases, external records of knowledge.
Technological development relies on a knowledge base and other elements of a civilization's kernel of resources. This implies only a slower rate of technological progress in a smaller population starting with the same kernel, all else equal.
Furthermore, differences in the kernel of knowledge, tools, education, values, lifestyle, luck, and culture of people beginning a civilization or existing at some point in its technological development could influence the rate and type of its development.
Network effects in human systems can include group-think. A larger more interconnected group is not necessarily more curious, intelligent, or insightful. Instead, the group can be the opposite.
The possibility of a larger civilization creates more opportunities for fragmentation of it into ideologically opposed but otherwise stable civilizations, resulting in enduring suffering for both.
People are products of their civilization as it functions for them in their personal context. It is a mistake to have a child before taking into account the context of that particular child's development, others involved, and that child's experience.
People start with the same potential for differing values regardless of their culture's aspirational values. Yes there many influences that can help to guide human values in individual cases to serve civilizational goals but it is not empirically evident that cultural or personal value aspirations can foster a long-term and desirable civilization.
Humans routinely fail to meet their own aspirations and even to recognize their own needs. Human cultures similarly fail. This is evidence that their civilizations inevitably fail.
However, if we see our potential for population growth not as a virtue but as a flaw, then a civilization that successfully maintains its own steady state population size would have desirable characteristics if discovered or developed.
Our own psychological bifurcation of altruism and selfishness would have to cease and the problems of our lack of intellectual integrity and enduring preferences would have to end in order to stop the cognitive manifestations of the human urge to procreate (among other things).
I expect that the problems of maintaining a steady state population would multiply as the population became larger. If I am right, then the question is not how many people the planet could sustain but how few people are needed to sustain a human civilization on the planet long-term or at least a million years.
I guesstimate a few hundred-thousand people but with the caveat that vices are stably absent from the lifestyles of the civilization's people and the problems of vice are known and solved rather than unknown and forgotten.
The problem of vice in human society (for examples, drug use or alcohol use or porn use or gambling) is unsolved. I suspect that it will not be solved. Vice as I mean it is a root cause of numerous human failings and inevitably leads to larger scale failures such as our current overshoot.
I am vulnerable to vices just like everyone else. I have no manifesto about how to deal with them and so no model for what makes a small and technologically advanced civilization stable for even a hundred years, much less a million.
Re this article and the moral argument for 100 billion, your views are virtually the polar opposite of my own Tomas. Which I find perplexing tbh.
For what it’s worth….you seem to associate ‘ happiness’ with prosperity or wealth, and with parenthood, which reflects narratives rather than the underlying reality which is quite different.
In my view one can either see this or they haven’t looked close enough, beneath the personas or presentations.
It isn’t immediately obvious but ‘happiness’, its presence or absence, is actually a taboo subject, like income or toileting habits. This is why we say we are “fine” whether true or false.
Humanity has never been as prosperous as it is today, yet nearly 50% of people in the prosperous world are experiencing depression, anxiety, or an undefined psychological malaise, and most of the rest experience the absence of meaning, purpose or fulfilment.
I’ll finish by saying something preposterous. Happiness is a state of neuropsychological maturation, and the journey towards achieving it. Adaptation to the ‘prosperity’ way of life, and parenthood, make the achievement of such maturation virtually impossible.
It is my view, therefore, that the vision you are describing would be catastrophic for our species.
We do have a fundamental imperative to strive for happiness and wellbeing, but the prosperity/consumption path represents a wrong turn.
I'm glad to hear that our views are polar opposites. There's information to be learned!
I don't quite associate happiness with prosperity. The stronger case I'm making is
that happiness *doesn't shrink with prosperity*, which is the fear of degrowthers. This is enough to make the moral case, because with current levels of happiness, more people is strictly better.
Current data on happiness shows some people are unhappy, but crucially the share of population that is unhappy hasn't increased over time.
Why do you say happiness is taboo? That's not my experience.
Why do you say "Adaptation to the ‘prosperity’ way of life, and parenthood, make the achievement of such maturation virtually impossible."? That's not my experience.
I don't see where in your comment you make the case that more prosperity equals less overall happiness.
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.
Why isn't China the happiest and richest country in the world, then, or India? Isn't it more likely that the technologies that enabled more population are the same that enabled all the other benefits? I don't see the proof that it is population and not scientific development that is important.
I highly recommend “Population Bombed” by Pierre Desrochers and Joanna Szurmak for a great overview of the link between population growth, economic prosperity and environmental health. The authors show that the benefits of population growth have actually been understood by humans for thousands of years, that no one is really making any new arguments today and that while pessimists are always disproven, they never really learn from history.
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.
At least in the US, more than twice as many “urban” residents actually live in suburbs and exurbs as live in the actual city. I technically am in an MSA. There are horses, cattle, goats, and sheep living on my road, and the smallest lots are 2 acres - largest are in the hundreds of acres. Your urban 80% includes millions of people living in similar areas.
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?
Relevantly to growing the world's population to 100B, most young children and parents of young children also hate living in cities.
Kids can't do developmentally important things like playing in dirt or running around outside with light supervision in a city. They'll get lead poisoning or get hit by a car. Most parents realize this and move to the suburbs or country where their kids can have a more human life. Some stay in the city but find raising kids there so difficult/unhappy that they stop after one or two.
Throughout history, cities have typically had a below replacement fertility rate. They're playgrounds for perpetually childfree adults, or networking hubs for young people to get established in their careers before they settle down elsewhere. Cities have always been reliant on a steady infusion of population from more vital areas. One might even argue that urbanization is the primary cause of the fertility collapse.
Whatever percentage of people would be happy living in Paris-like conditions, the number will be lower if they have the needs of a family in mind.
Suburbs and rural areas aren't perfect either, but they're better for families than Paris is. Still, there are many ways suburbs and urban areas like Paris could be made more family friendly. Primarily, there need to be larger (shared when necessary) green spaces that are fenced or in an apartment courtyard. A 4yo should be able to come and go outside without danger of cars while their parent watches them occasionally from the ground floor of their home. And those homes need to be big enough for a family of 5+ and affordable enough to live on a single income, if families are to be able to focus on having the kids and family life that most people want. Probably one of the only ways to get to 100B would be to guarantee families homes at least that appropriate.
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
You have not made your argument. There is no reason to believe that shrinking population would decrease GDP per capita, and powerful arguments that it would not.
What you are describing is a crowded dystopian hellscape, not a paradise.
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!
Your replies in this thread point into other direction - unsubscribe and never come back here. Your lack of willingness to engage with a reasonable arguments and desire to push your content and values without solid backup are pathetic.
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…
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.
Free choice is not the problem. For starters, it doesn't truly exist. Also, it's heavily influenced by external factors, like culture and economics. Finally, the actual number of children is lower than the desired number, as I explain!
Free choice is not a problem! That should be clear but not all the world agrees. There might be too few children for you but you need at least one woman to agree with you.
According to the actual data on growth and overshoot, we peaked already not due to population density but due to the resources ot takes to keep this level of civilization running as it is. Land isn't an issue, farmland is. You can't just say you did research and not back it up.
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.
Interesting as always Tomas. You're taking a very Panglossian view in these articles. I think you overestimate the ability of technology to "fix" problems and underestimate the impact of environmental, economic, and social constraints. Desalination holds much potential, but to do this at a scale sufficient and rapid enough to compensate for the accelerating depletion of fresh water sources will be economically prohibitive for much of the world. Similar consideration applies to global warming. Even assuming the transition to renewable energy imcreases in scale and speed, there is hysteresis in levels of greenhouse gases in the atmosphere and ocean acidification. If the world stopped using fossil fuels tomorrow, these gases would remain at high levels for some years, and the extreme weather impacts we're experiencing would persist. We know that fossil fuel use will continue for years to come, especially if Trump has his way. Parts of the world are approaching temperatures that will make them uninhabitable for much of the year. Another factor is whether economic systems can sustain 100B people. Seems that increasing numbers of economists are concluding that neoliberal capitalism is a failure because it transfers wealth upward and leaves others worse off than they were before Clinton era. The current gross levels of wealth inequality are unsustainable and one could interpret the 2024 election as an expression of widespread anger about the staus quo. I find it hard to envision large increases in population in the absence of radical economic changes. Not going to hold my breath for that. Finally you seem to assume that there is a linear increase in creativity and innovation with population. But I doubt that's true, judging by my 70 years of interaction with people. Sorry to go on so long. You raised so may interesting questions!
Thanks!
I think I explain in the article with data why the water depletion you fear is not the case.
Desalination today is cheaper than municipal water in virtually any city in the world.
As discussed, for crops it's already viable in most places.
Not for *all* crops, but for many. And the only thing that stops us from every crop is simply investment in greenhouses, which is happening anyways.
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.
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!
I agree that human population growth can allow increasing specialization, all else equal. However, it is a mistake to assume that human knowledge exists in human memory. Scientists and researchers commit information to knowledge bases, external records of knowledge.
Technological development relies on a knowledge base and other elements of a civilization's kernel of resources. This implies only a slower rate of technological progress in a smaller population starting with the same kernel, all else equal.
Furthermore, differences in the kernel of knowledge, tools, education, values, lifestyle, luck, and culture of people beginning a civilization or existing at some point in its technological development could influence the rate and type of its development.
Network effects in human systems can include group-think. A larger more interconnected group is not necessarily more curious, intelligent, or insightful. Instead, the group can be the opposite.
The possibility of a larger civilization creates more opportunities for fragmentation of it into ideologically opposed but otherwise stable civilizations, resulting in enduring suffering for both.
People are products of their civilization as it functions for them in their personal context. It is a mistake to have a child before taking into account the context of that particular child's development, others involved, and that child's experience.
People start with the same potential for differing values regardless of their culture's aspirational values. Yes there many influences that can help to guide human values in individual cases to serve civilizational goals but it is not empirically evident that cultural or personal value aspirations can foster a long-term and desirable civilization.
Humans routinely fail to meet their own aspirations and even to recognize their own needs. Human cultures similarly fail. This is evidence that their civilizations inevitably fail.
However, if we see our potential for population growth not as a virtue but as a flaw, then a civilization that successfully maintains its own steady state population size would have desirable characteristics if discovered or developed.
Our own psychological bifurcation of altruism and selfishness would have to cease and the problems of our lack of intellectual integrity and enduring preferences would have to end in order to stop the cognitive manifestations of the human urge to procreate (among other things).
I expect that the problems of maintaining a steady state population would multiply as the population became larger. If I am right, then the question is not how many people the planet could sustain but how few people are needed to sustain a human civilization on the planet long-term or at least a million years.
I guesstimate a few hundred-thousand people but with the caveat that vices are stably absent from the lifestyles of the civilization's people and the problems of vice are known and solved rather than unknown and forgotten.
The problem of vice in human society (for examples, drug use or alcohol use or porn use or gambling) is unsolved. I suspect that it will not be solved. Vice as I mean it is a root cause of numerous human failings and inevitably leads to larger scale failures such as our current overshoot.
I am vulnerable to vices just like everyone else. I have no manifesto about how to deal with them and so no model for what makes a small and technologically advanced civilization stable for even a hundred years, much less a million.
Re this article and the moral argument for 100 billion, your views are virtually the polar opposite of my own Tomas. Which I find perplexing tbh.
For what it’s worth….you seem to associate ‘ happiness’ with prosperity or wealth, and with parenthood, which reflects narratives rather than the underlying reality which is quite different.
In my view one can either see this or they haven’t looked close enough, beneath the personas or presentations.
It isn’t immediately obvious but ‘happiness’, its presence or absence, is actually a taboo subject, like income or toileting habits. This is why we say we are “fine” whether true or false.
Humanity has never been as prosperous as it is today, yet nearly 50% of people in the prosperous world are experiencing depression, anxiety, or an undefined psychological malaise, and most of the rest experience the absence of meaning, purpose or fulfilment.
I’ll finish by saying something preposterous. Happiness is a state of neuropsychological maturation, and the journey towards achieving it. Adaptation to the ‘prosperity’ way of life, and parenthood, make the achievement of such maturation virtually impossible.
It is my view, therefore, that the vision you are describing would be catastrophic for our species.
We do have a fundamental imperative to strive for happiness and wellbeing, but the prosperity/consumption path represents a wrong turn.
Food for thought maybe. 😆
I'm glad to hear that our views are polar opposites. There's information to be learned!
I don't quite associate happiness with prosperity. The stronger case I'm making is
that happiness *doesn't shrink with prosperity*, which is the fear of degrowthers. This is enough to make the moral case, because with current levels of happiness, more people is strictly better.
Current data on happiness shows some people are unhappy, but crucially the share of population that is unhappy hasn't increased over time.
Why do you say happiness is taboo? That's not my experience.
Why do you say "Adaptation to the ‘prosperity’ way of life, and parenthood, make the achievement of such maturation virtually impossible."? That's not my experience.
I don't see where in your comment you make the case that more prosperity equals less overall happiness.
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!
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!
Why isn't China the happiest and richest country in the world, then, or India? Isn't it more likely that the technologies that enabled more population are the same that enabled all the other benefits? I don't see the proof that it is population and not scientific development that is important.
Agree 100% and well said, Tomas!
I highly recommend “Population Bombed” by Pierre Desrochers and Joanna Szurmak for a great overview of the link between population growth, economic prosperity and environmental health. The authors show that the benefits of population growth have actually been understood by humans for thousands of years, that no one is really making any new arguments today and that while pessimists are always disproven, they never really learn from history.
This has given me a lot to think about, thanks.
I think you could include the Simons-Ehrlich debate about overpopulation here, it is quite relevant.
https://en.wikipedia.org/wiki/Simon%E2%80%93Ehrlich_wager
True! I left it out but it's an obvious one to add. After that, I would have become a bit humbler than Ehrlich!