Why do we worry about overpopulation? What’s so bad about it? Well, several things. We could have too many people with respect to the space available on Earth; too many people and not enough jobs for everyone; too many people and not sufficient resources; too many people polluting the environment beyond what it can take.

All these potential problems need to be discussed. Thus, in this article I’m going to play accountant a little bit. You can read the whole article, or jump to the section that concerns you the most.

Space

According to the UN, the minimum floor space needed for a person to live decently is 20 m2. How much space do we have on Earth?

The total dry land on Earth is about 148,939,063.133 km2, and half of that is to be divided among deserts, mountains, and other unsuitable terrain; that means that, in reality, 0.5*148,939,063.133 km2 = 74,468,531.57 km2 are suitable for human use; of that, say we reserve one-tenth for our people grid, and all the rest for farming, forests, factories, and the lot. The area reserved for people is then 7,446,953.157 km2, i.e. about 7,446,953,157,000 m2. Divide that by an extra-luxury estimate of 80 m2 of floor space per person to get about 93,086,914,462. In other words, we can place over 93 billion people (roughly 12.4 times the current population) in one-tenth of the estimated habitable land, with 80 m2 of space each—let alone if we used more habitable land.1

If you take into account that we are able to create structures that range from buildings with several floors each to soaring skyscrapers, you’ll realise quickly that we can actually have a lot more people than the already huge number I gave you above. So, nope, we don’t have a space problem. (If you’re squeamish about Wikipedia being used as a source, here and here you’ll find similar estimates for Earth’s dry land and water surface.)

Of course, we just can’t go on packing more and more people forever on the same planet; at some point, the place will likely be a little crowded. If we had over 90 billion people today, I suppose it would be slightly catastrophic because we don’t have the infrastructure to support that many people at the moment. The point of my reasoning thus far isn’t that we should have 90 billion people around; the point is that if we have the space for that many people, then we have space for a number of people smaller than that but far larger than today’s current population.

However, in practice it would take a really long time to reach a population of several dozens billion people; in fact, with or without rejuvenation, it is unlikely we ever will. I will elaborate more on this in the Population dynamics article, but for now know that, if we are ever going to reach that kind of numbers, in the most catastrophically apocalyptic worst-case doomsday scenario it will take at least a hundred years—and I’m talking about reaching something like 30 billion people; no way we could get to 90 billions in 100 years. Over such huge timescales, worrying about this (potential) problem now is a touch premature, just like worrying today about the Sun’s death would be.

The Sun is scheduled to blow up and engulf the Earth in about 5 billion years. Today, we stand exactly zero chances of solving the problem in any way; however, it is entirely reasonable to think that even just a few hundreds thousand years from now we may have knowledge and technology that could make the problem trivial to solve—for example, we might have interstellar travel technology, or we might even be able to revitalise stars. It’s hard to actually predict what we’ll be able to do then, but you can bet our grasp of the problem will be much more solid than it is today, and we’ll be better equipped to solve it. Similarly, before we get to too many billions of people wandering about the Earth, you can expect the colonisation of suitable nearby celestial objects, such as the Moon or Mars, will either be a thing or about to become one. (Tesla cars and SpaceX‘s entrepreneur Elon Musk is already pushing for this today.)

Bottom line: We’ve got plenty of room on Earth, and assuming we’ll ever run out, it’ll take so long that we’ll likely have found more room elsewhere.

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Environment and resources

Overpopulation is a multifaceted problem. We may well be not overpopulated with respect to available space, but we easily could be in terms of availability of resources, or of environmental impact. Given our present-day technology, a 30-billion population would be absolutely unthinkable under many respects. Speaking of the environment, a population of that size using today’s technology would cause the amount of greenhouse gases (or GHGs) in the atmosphere to skyrocket. In a nutshell, high levels of greenhouse gases in the atmosphere are the cause of global warming, which in turn is the cause of a number of rather annoying phenomena, such as more intense storms, increase of the sea level, and more acidic oceans. The amount of greenhouse gases each one of us produces in a given amount of time is called the carbon footprint. The production of GHGs may occur naturally as well, but we know for a fact that several human activities produce GHGs too and thus have carbon footprints that contribute to the problem: energy production, passenger transport, food and textile production, and others. The bad news is that the amount of GHGs is already high enough that global warming has already begun; the good news is that we’re aware of the problem and have already started to work on several solutions.

Energy production

Our energy production still relies heavily on rather primitive sources that pump more GHGs up into the atmosphere or anyway have negative environmental impact, such a the infamous coal, oil, and to an extent also biofuels. More environmentally friendly alternatives to these sources of energy exist—solar, wind, hydroelectric, and even clean coal, to name a few. Even the so much frowned-up nuclear fission is a better option than traditional energy sources; its environmental impact is lower than coal & co., though it does pose risks in terms of spent fuel and meltdowns, for example.

The energy needs of the world have increased over time, and as more and more of the world become more developed, the trend is likely to continue. On top of that, it goes without saying that more people means more energy to be produced, potentially leading to further negative environmental impact—unless we can come up with cleverer solutions.

Relying more on renewable energy (i.e., the alternatives I mentioned above) is sure a possibility. I’m not sure whether we could run the planet entirely on 100% renewable at the moment; some (not exactly neutral) parties say we can, others say we can’t, and the debate is open. (Want to read more? Try this or this, for example). However, for the purpose of this article, the question is, is there any way we could be able to satisfy the energy requirements of a world population that has hypothetically grown huge because of rejuvenation, possibly without screwing over the planet in the process? The answer is yes, most likely so. Enter nuclear fusion.

While the word ‘nuclear’ has become synonym with apocalyptic scenarios of destruction, radiation poisoning, cancer, and the lot, we really need to stop thinking this way. Nuclear fission does come with a bunch of possible problems, but nuclear fusion is an entirely different story.

Nuclear fission, as intended for energy production, is the process of splitting atomic nuclei into smaller ones by means of neutron bombardment. Put it simply, you throw a neutron at an atom and split it in two, releasing both energy (which you harvest) and more neutrons in the process. The atom you split (usually uranium or plutonium) is surrounded by many others; the neutrons resulting from the first splitting eventually hit other atoms, causing them to split, ultimately leading to a chain reaction. This is why fission is dangerous if containment is lost: The reaction can propagate outside the reactor and wreak havoc.

Nuclear fusion, though, is not a chain reaction. Fusion is the same power that stars use to shine. Basically, stars are so huge that the hydrogen gas they contain is subject to huge pressure. This pressure causes nuclei to fuse together into heavier nuclei, releasing tons of energy in the process. We can’t really put together as much gas as in a star here on Earth, so the enormous pressure required to keep a fusion reaction going has to be obtained through different means—for example, by compressing the fuel target by focusing powerful lasers on it. Containment is a very important part of the fusion process as well, but not so much for safety than for actually keeping the reaction going: If you were to lose containment, the compressed gas would spread around, touching the wall of the reactor and thus cooling down. As the gas cools down and spreads around, its pressure drops dramatically, stopping the reaction altogether. While a fission reaction can propagate outside the reactor, a fusion reaction simply can’t do that because of the very nature of nuclear fusion itself.

Aside from being much safer than fission, fusion comes with many other advantages, such as abundance of easily obtainable fuel, virtually infinite energy almost for free, and zero emission of GHGs. You can learn more about fusion in this very instructive video by Kurzgesagt. (You may also want to check out their other videos on nuclear energy).

We don’t have fusion yet, and some sceptics say that fusion has been 50 years away for the past 50 years; this, however, only shows how thick they can be, and how disrespectful they are not only of the difficulty of the problem, but also of the efforts scientists are putting into cracking it. Fusion has been achieved, numerous times, except that at the moment it is not cost-effective. It takes much more energy to get the reaction going than you get back, but progress has been made. There are several existing prototype reactors that are expected to become functional in 20-30 years, such as ITER, the Wendelstein 7-X stellerator (which has recently made exciting progress), and DEMO; other designs, such as Lockheed Martin’s High-Beta Compact Fusion Reactor and General Fusion’s Magnetised Target Fusion Reactor are in the works. Sooner or later, somebody will crack this nut, and the sceptics will have to look for something else to brainlessly criticise.

Bottom line: There are ways we can meet the energy demands of a much, much, MUCH larger population with much, much, MUCH smaller environmental impact. Patience and hard work are the key.

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Food production

Just like energy production, food production is (at least) a two-faceted problem: Would we be able to produce enough food for a much larger population? Furthermore, would we be able to do so without harming the environment?

Let’s start from the usual suspects: meat, fish, and dairy products. All of these products pose quite some problems, not only in terms of animal suffering and killing, but also in terms of environmental impact. For example, according to Livestock’s long shadow, a report by the Food and Agriculture Organisation (FAO), livestock is responsible for the emission of significant amounts of GHGs; it uses up to 70% of all agricultural land, and represents about 8% of our water use. While we could do with eating a bit less meat and dairy, especially in the industrialised world, if the world population were (let me stress again, very hypothetically) to double or triple because of rejuvenation, the global demand for these products would likely increase as well. Veggies aren’t exempt from creating problems too: If need be, would we have enough land to cultivate much more food than we do now?

When it comes to meat and dairy, the solution may be resorting to lab-grown products. By now, you’re probably already aware that lab-grown meat is coming: The first lab hamburger (should we call it a lab-burger?) was created in 2013 with a staggering cost of 325.000$, but now the cost has gone down to 11$ per burger. Startups like Super Meat and Memphis Meats have joined the field and are working on cheap ways to create safe and delicious meat (including poultry). It goes without saying that lab-grown meat would have a range of advantages: no animal suffering; drastically reduced land use (you know, labs are smaller than your average pasture); increased production at a lower cost (you don’t need to grow and feed entire animals—you only grow the meat you need); elimination of GHGs due to animal digestion (yeah, that’s right, too many cow farts are bad for the environment); no risk of pathogens and no need to use antibiotics (real animals out in the fields can contract all kinds of diseases; lab-grown meat is created in a sterile environment and doesn’t have this problem); enhanced nutritional value (engineered meat can be designed to contain less fats, or more specific proteins, for example). Meat isn’t the only thing that we could grow in a lab: seafood, egg whites, and dairy are possible too. Heck, even leather (which you probably don’t eat, but anyway). I don’t want to jump to conclusions, but more sustainable, efficient, cheaper, eco- and animal-friendly food production seems to be possible and will probably happen in the foreseeable future, well before any huge population increase can happen.

Similarly, the use of genetically modified organisms (GMOs) may be the key to yield better and more abundant crops. GMOs are a bit in the middle of a shitstorm, but not for any valid reason. You’ll forgive my bluntness, but the controversy can be summarised as follows: People don’t understand science, freak out when they hear big words like ‘genetic’, or ‘lab-grown’, and have a thing for conspiracy theories where the big faceless corporations always and only play the villain, while your average Joe with no scientific training whatsoever somehow has figured it all out and unmasked their evil plan to destroy the world. The truth is, we’ve been creating GMOs since the dawn of times with selective breeding—simply a slower and factually much less precise way of deciding which genes you put into an organism—and both the World Health Organisation and the Food and Drugs Administration have assessed that GMOs presently on the market are just as safe and nutritious as traditional food. Not only are GMOs just as safe and good as the old stuff, but they can be made more resistant to parasites, they can be engineered to yield larger crops, and have a range of environmental and economical benefits. Those claiming that GMOs are default-bad for you have little-to-no idea what they’re talking about, and studies that ‘prove’ GMOs are bad have been debunked time and again. You can find more about this topic here and here.

Techniques such as aquaponics, hydroponics, and aeroponics may also prove useful; you can read more about this and other resource-related concerns on LEAF’s relevant article.

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Other

There are certainly many more things that might go apeshit if we had too many people around, and I’d be a fool to think I can address or even just cover them all. As a last example, let’s consider transportation. We release tons of GHGs with cars, ships, planes, and the lot. Sure, one fine day oil will finally be over, but before then we will have polluted the atmosphere much more, and anyway we need to think about a substitute for oil before we run out of it. Electric cars, such as Tesla cars, are part of the solution, and it might be possible to have electric planes too. Especially if we hit bullseye with nuclear fusion, we might be able to create smaller reactors to power planes and ships. (Nuclear fission propulsion is already a thing; if fusion works, it isn’t too far-fetched to think we can do the same with it.)

The bottom line is that, as our technology grows more sophisticated and efficient, we increase the human carrying capacity of the planet—i.e. the ability of the planet to sustain us. It’s a friend we’ll meet again the the Population dynamics article. The number of people we can have on Earth isn’t fixed at all, and it depends largely on how clever we will be in the future, in terms of maximising the efficiency of our technology while minimising its environmental impact as well as that of our lifestyle.

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Jobs

Lack of jobs is already quite the problem today, even though we age, get sick, retire, and die; let alone if we never aged to begin with and we had more and more people in need of a job. Sounds obvious, right? It sure does, and that’s exactly why you should be suspicious. Always be sceptical of that which sounds obvious.

This topic is a bit of a worm can, and I’ll need to open it at least a little bit. However, the ramifications of the topic are too many and only very tangentially related to the scope of this article (or website!), so you’ll forgive me if I won’t deal with each and every of the finer points. There may be different reasons why job scarcity is a thing, but I’ll focus only on one that is presently all the rage: automation.

The days when technological unemployment belonged to the realm of fiction are long gone. People have been worrying for quite a while now that robots will take their jobs and force them to look for another way to support themselves. If you don’t believe me, you probably haven’t been browsing the Internet too much in the past few years, and in case you’re wondering what’s the matter with this sentence, every word in it is linked to a different article about technological unemployment and how robots will take your job.

So, yes, there’s cause for concern. Or not.

People are right to be worried, because they need a job to live. On an individual level, it sucks big time to be fired because an algorithm made you redundant. The difficulties and sometimes social stigma tied to being unemployed are not something I’d wish to anyone. However, from a global perspective, this panicking and sometimes raging against automation is quite amusing. Machines aren’t building themselves. We are, and the reasons we do it haven’t changed much throughout history: We build machines to do work which we either can’t or don’t want to do. That’s why I say this is amusing. We’re building machines to do more and more work for us, and then we complain there’s no work for us to do.

For a long part of history, machines weren’t quite as sophisticated as they are today, and they could only ease work that you still needed to do yourself to at least some extent. Until machines are like that, there probably isn’t much choice for an economic system: Most if not all jobs (especially indispensable ones) can only be done by people, and if the system is set up so that people need to have a job to live, these jobs will get done and everyone will (in principle) be (more or less) happy. We’ve had this system in place and running since time immemorial, so it’s no surprise if everyone thinks you need a job to live. The truth is, you don’t. Not strictly speaking. Mainly, you need food, water, sleep, and shelter. You don’t eat jobs, and you don’t drink money. This is exactly why this paradigm is becoming problematic now that machines are getting smarter. Machines keep doing what they were designed for—relieving us from the burden of work—and are getting better and better at it, to the point that they could soon relieve us from most if not all work; yet, we still have a system where if you don’t work, you can’t get what you need to live. If we were dumb enough, we could end up in a situation where machines do all the work and produce tons of things, but nobody’s getting those things because, well, nobody’s working and getting the necessary money to buy stuff… Luckily, we aren’t that dumb.

It’s clear that growing automation and the way we think about work are incompatible. Giving up automation would be like shooting ourselves in the foot with a hydrogen bomb, so what we need to give up is this old-fashioned idea that individuals need work to live. I think that’s completely flawed. Presently, the system seems to be set up so that we work to ensure our individual survival, and the thriving of society is only a consequence of it. In my opinion, we’d be better off if we looked at the problem from a different perspective. Society needs work to exist; the existence of society, in turn, will grant individual survival. We should work to keep society going, knowing that this will allow each of us to live. Individual survival should be uncoupled from work.

I’m hardly the first one talking about this problem. For several years now, the idea of a universal basic income (UBI) has been gaining traction. In a nutshell, a basic income is a flat monthly sum of money the State pays to every citizen/resident, no strings attached. The details of UBI are far too off-topic, but suffice it to say that a lot of academic research has been done on UBI, several experiments have been run, and the results were overwhelmingly that UBI did not exacerbate social problems and actually reduced them, it reduced poverty, improved the rate of school attendance among children, boosted the economy and helped creating new businesses. More data about UBI pilots can be found here; other examples of pilots are Finland’s and Netherlands’.

UBI is not intended to allow everyone not to work, but rather to allow you to live decently despite being unemployed. After all, the problem of unemployment is not one of not enough work getting done; it is a problem of people being unable to live despite more than enough work is constantly being done. The ultimate reason why we do work is to stay alive, and it’s ridiculous that, when more than sufficient work to keep everyone alive is already being done, we still need to ‘create new jobs’ whose only purpose is to allow people to earn a living—a rather sugarcoated way to say that people don’t deserve living by default and that their existence must be justified to others somehow. In the words of Buckminster Fuller,

“We must do away with the absolutely specious notion that everybody has to earn a living. It is a fact today that one in ten thousand of us can make a technological breakthrough capable of supporting all the rest. The youth of today are absolutely right in recognising this nonsense of earning a living. We keep inventing jobs because of this false idea that everybody has to be employed at some kind of drudgery because, according to Malthusian-Darwinian theory, he must justify his right to exist. So we have inspectors of inspectors and people making instruments for inspectors to inspect inspectors. The true business of people should be to go back to school and think about whatever it was they were thinking about before somebody came along and told them they had to earn a living.”—(New York Magazine, March 30, 1970, page 30.)

This concept was expressed much more succinctly by Federico Pistono in 2014:

“Maybe the problem isn’t that jobs are going away. Maybe the problem is that the economic system requires jobs in the first place for people to live.”

As machines become smarter and smarter and more able to replace us pretty much in every context, the idea of creating new jobs becomes increasingly retarded. As machines do more and more of the useful and hard stuff, we’ll be left with no option but to create idiotic, pointless jobs that have no real utility whatsoever. At that point, we may just as well let the machines do all the stuff that is necessary to our survival but too tedious or dangerous for us to do, or simply anything we don’t really fancy doing, and dedicate ourselves to the work we like doing. The idea that people are fundamentally lazy and would not work unless forced is bogus, and we all know that. I agree that nobody would do monotonous, repetitive, and soul-crushing jobs—like flipping burgers, mopping floors, cleaning toilets, and picking tomatoes—unless forced; but I have a hard time believing that engineers, physicists, surgeons, archaeologists, philosophers, astronauts, musicians, and painters, for example, do the work they do because they have to ‘earn a living’. Machines don’t have to do everything, and they won’t unless we order them to. We can make them do only what it takes to allow us to live and take care of the rest ourselves, but not to make ends meet; rather, because we’re passionate about it. As Frances Coppola put it in The changing nature of work,

“I fundamentally disagree with those who think that people must be “forced” to work, or that government should “guarantee” a job. […] If people are intrinsically of value, then they have the right to survive with or without working. I therefore think we should guarantee basic income, rather than jobs. […] If people don’t have to work to survive, most will find or create work that fulfils themselves and benefits others, and we will all be the richer for it. There will be some who will opt to do nothing, but in my view they will be a small minority and we will be rich enough – and I hope generous enough – to tolerate their laziness.”

I bet you turned up your nose at the last bit of Coppola’s quote. ‘If I have to work,’ you probably thought, ‘then everyone else should too!’ Right? Doesn’t this show that, deep inside, we think work is an unpleasant activity which we wouldn’t do unless forced? We do, but this isn’t so much about our attitude towards work. Rather, it’s because as long as our living depends directly on a job, a lot of us will end up doing something they hate out of necessity. If you have to do something you dislike to support yourself, the thought that other people can just do nothing and yet be allowed a living feels unjust. This, however, only happens when you’re forced by circumstances to do a job you don’t like.

Imagine a system like what I was talking about some paragraphs above. Dull, dangerous, repetitive jobs are either fully automated or made unnecessary through technology; we have UBI or some other system that guarantees everyone’s survival. You don’t have to take up jobs you don’t like any more (which thus far has been something of an issue). You can take all the time you want to find out what you want to do. You can come up with your own business, or go back to studying, or you can keep applying for other jobs you love, knowing that even if you fail your living is not jeopardised. Once you are doing the job you love, what do you care if other people are doing nothing instead? We don’t need everyone to work to keep the world going, and you’re doing what you do out of passion. If anything, you’ll probably feel sorry for those lazy arses who, in a world of infinite possibilities, chose to practise their thumb-twiddling skills over all of that there is to explore and experience.

In the system I described above, the first requirement isn’t strictly necessary. We don’t need to have a very large degree of automation before we implement UBI and uncouple survival from work. We’re already getting there. If we had such a high level of automation (and we’ll probably have it relatively soon), we might even be able to finally get rid of money altogether, something I’ve been dreaming of for ages. As the cost of living becomes more and more demonetised, a price tag for things becomes more and more pointless. Some people think this will never happen because of scarcity; however, scarcity can be reduced as our means of production become more efficient, and I’m not at all convinced that a moneyless system would necessarily require zero scarcity. But I digress.

Let’s finally go back to the main question. If rejuvenation caused the population to skyrocket, would we have enough jobs for everyone? Probably not, given that unemployment is already a thing, but what matters is that the premise of this question—that everyone needs a job to live—has been cracking for a while and it’s likely to eventually fall apart. By the time rejuvenation might (might! I’ll never stress this enough!) cause a huge increase in the population, odds are that the current paradigm will have been replaced by one where unemployment has been made irrelevant.

You might think I’m just playing the trump cards of the huge timescales and technology and not really answering the question, but the fact is, you can’t apply possible far-future scenarios to present-day situations. If we had 15 billion people on the planet today it would likely be an unemployment catastrophe; but does it make sense to assume this would be equally catastrophic 100 years from now, especially when we’re already seeing the signs of change taking place? Would it have been a good idea to not develop vaccines and introduce simple hygienic practices in the early 1800’s because they would reduce the death toll and thus might cause sufficient population growth to produce an unemployment crisis in a century or so? I’ll leave it up to you to decide. (Hint: No, it’d have been mental.)

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