The Bay Area seems to have 18,000 km² which at 7.1 million people makes is quite dense already.
The bay area average is 868 people/sq mile.
No, the bay area is not dense at all.
If anything I'd argue the steps towards prosperity in an ecologically sustainable way in this scenario are shorter for developing countries, it will protect their ecology (it is the third world who works in the strip mines for the batteries for affluent tesla drivers in California), accelerating digitization is cheaper than traditional infrastructure, it gives them the opportunity to leapfrog over traditional industries, it will drastically reduce the impact of climate change and so on.
This not what I meant.
I mis-read OPs
>> welcome the economic decline that would come with growth reduction
as no growth. If the (slow) growth (magically) only goes to the poor they may indeed eventually catch up.
Or put differently, would you forgo having children and grandchildren so that others can have this future you imagine?
That said, your parent comment probably meant “our” grand children, just a guess.
Even then, this would only work until the population has shrunk to a certain point. Then what?
Maybe a more useful way forward would be to question if we need perpetual growth at all.
If I know I'll be selling 20% less widgets in 5 years as population falls, I wont upgrade my widget making machines. Suddenly the people making widget making machines are all unemployed. They stop buying widgets and my sales fall even further. That's ok when it happens in one sector but what about when it happens in every sector?
There are other examples: researching a cure for a disease might make sense if there are 100,000 sufferers but not 20,000. If x% of the economy is used for scientific research, you can afford a lot more LHCs with 500m people than 50m.
Growth has to fall as we have to cut population or nature will do on it for us. But it will be a difficult project with strange political outcomes.
More likely they are going to retire before they are unemployed. Working age population always declines earlier than population as a whole.
I think it's pretty clear that there is a rate of population decline that is consistent with rising living standards as long as the decline is ultimately limited.
We should indeed focus far more on productivity. If the number of sufferers from a disease falls to a fifth while research productivity increases five times, finding a cure will make just as much sense as before.
Im all for productivity, but we are very very bad at making sure productivity growth doesn't mean shrinking incomes for the majority. So be careful welcoming the closure of the widget machine factory (or it getting more efficient and laying people off).
There is a rate of population decline that's consistent with economic growth. But its very small.
Three things generally grow economies: pop growth, productivity improvement and technological advance. If your pop growth is negative, you need the others to be big positives. Except that productivity growth is hard to achieve, hard to measure, and (as above) needs a lot of political management to achieve without leading to serious social issues. So you're reliant on technology. And technology isn't really moving much at the moment.
Japan and China have both suffered these combined effects for a while. Falling, aging populations. China has been fine because they can increase both the technological and productivity levels of its economy. It can move from doing things manually to semi automation (now basically done) and it can move from doing low productivity work (putting things together) to making entirely new products. Japan can do either.
Thats why China has managed huge growth (maybe not as good as they like to claim but still) over the last 30 years. And Japan has basically languished.
We are turning into Japan, not China.
I didn't say economic growth. I said living standards. The important difference is that living standards can go up while GDP is falling.
>We are turning into Japan, not China.
Japan proves my point. The country isn't exactly impoverished, nor is it getting any poorer. They have very low unemployment and GDP per capita has grown about 10% between 2010 and 2018. That's compared to 12.5% for the US. Not a bad outcome in spite of a steep decline in population.
Isn't it time to switch to plugin making machines then ? Setup a market opportunities study to try and see how to recycle skills, know-hows and professional network?
That's sort of the issue here: too many people, not enough jobs. And an economic/political system that assumes getting a job is possible for everyone.
Which is exactly what is happening. By every metric imaginable the entire population of the planet is gaining in wealth. Some quicker then others. But gains are largely universal. Poverty is at it's lowest point in all of human history. And in a month it'll be even lower.
Also when wealth goes up, overall consumption as measured by actual natural resources consumed goes down. People have this misconception that increased wealth equals increased consumption, which is hardly the case. Wealth represents a increase in well being, which more often then not, is a result of increased efficiency.
By 'increased efficiency' I mean less human effort is required to produce more with less.
Imagine country A, awesome with very little income inequality. Half it’s citizens earn 9k a year and the other half 10k a year.
Now country B, is very bad. 90% make 50k a year and the other 10% make 500k. That’s terrible, isn’t it? I wouldn’t want to live in country B.
Never in the history of the world have the poor had less than nothing.
“ What Roser’s numbers actually reveal is that the world went from a situation where most of humanity had no need of money at all to one where today most of humanity struggles to survive on extremely small amounts of money. The graph casts this as a decline in poverty, but in reality what was going on was a process of dispossession that bulldozed people into the capitalist labour system, during the enclosure movements in Europe and the colonisation of the global south.” 
(People beating the growth-growth-growth drum are also typically on the rich end of the spectrum btw).
Or, I think I've heard it said better, "If the purpose of life isn't 'maximizing shareholder value', we're fucked".
Of course, economic growth is not sufficient for this, but it is necessary.
Many countries have social security systems that rely on the economy being big enough to pay for it.
Growth cannot go forever due to these factors I observed:
1. More and more wealth seems to be captured and locked away somewhere while the rest of the populace is left to having to cope with globally dwindling redistributable capital.
2. Population isn't even declining everywhere but I've read several times here in HN that white people in first-world countries procreate less and less. Reasons can be a lot and my anecdotal evidence is that the cost of a basic life and some small extra affordances goes up every year. Families get more and more conservative on their spends and/or jobs. Many people here in Eastern Europe just decide to live on welfare and half-day crappy jobs somewhere but at least these jobs aren't stressful and don't require 2-3 hours in traffic every day. When you do the math such a way of life nets them 70-80% of what they would otherwise make so their choice is really quite logical. In these conditions the economy stagnates and companies get desperate for good staff while the government couldn't care less.
3. The population declines at places because people view raising kids as a huge financial and stress investment and not as the life-fulfilling purpose that raising kids is usually viewed as. This is mostly related to how much time is needed for a young person these days to actually start contributing to their raising (or new) family. Many people are just scared if they are going to be able to be financially stable for 25-30 years in the future. Others like myself are just burned out.
4. The economy gradually seems to be taken over by the very classic breed of venture investors that don't give a hoot about organically growing your customer base or actually taking care of your employees. Even in a presumably more conservative market like Europe, I see this more and more. Can we even discuss growth if, even against all odds, your company becomes hugely successful BUT has to return the investments tenfold? Again, this is a captured wealth going to somebody else's pocket (and they don't seem to be interested in redistributing it).
I could be gravely mistaken and be a victim of living in a filter bubble. Of course.
But it's what I am seeing periodically and it worries me. People just don't care that much for making kids or looking for jobs since it all just guarantees suffering and sacrifices and nothing much else.
Many elderly people tell me that they regularly chat with their kids (now 30-45) and are convinced that having a fulfilling life was easier even as back as 20-30 years ago. They might be right.
The world news story is the rest of the world rapidly approaching that, even in many not so rich places.
Within developed countries, I'm only particularly familiar with US data, but what's happening in the US is that the big minority + immigrant groups are what's showing the biggest drops, moving them towards the white birthrate.
Sounds that way to me.
Fertility goes down when women enter the workforce and have access to contraceptives. This is also when countries become prosperous. There's no reason to have five children when childhood mortality is low, pregnancy isn't risky, and you can have sex without getting pregnant.
I don't believe the whole "cost of living is going up" stuff that millennials constantly whine about. It's perfectly affordable to live in most places in the US. Millenials are victims of the college loan scam, i.e. going into debt for a worthless degree because "that's what you're supposed to do". They, their parents, the government, and especially the colleges are complicit in this victimization.
> But it's what I am seeing periodically and it worries me. People just don't care that much for making kids or looking for jobs since it all just guarantees suffering and sacrifices and nothing much else.
This kind of nihilism is related to affluence. It infects most people who go through the college system and never experience any struggle.
> Many elderly people tell me that they regularly chat with their kids (now 30-45) and are convinced that having a fulfilling life was easier even as back as 20-30 years ago. They might be right.
Again, this has to do with affluence and not the "world being worse/more expensive/etc". Happiness is related to struggle. Wearing yourself out, renewing your energy (sleeping), and then doing it all over again is the source of all sustained happiness. Increasingly, many people can opt out of this cycle, and it's making them miserable.
IMO, this is a pretty silly idea.
The fundamental problem with this theory is that there are sub-populations that have been able to maintain high fertility despite the decline in broader society.
For example, the number of Amish doubles every 20 years. Today, there are 1/3 of a million Amish. At the current rate, it'll only be 200 years until there are more than 300 million Amish in the US.
No idea if that will actually happen, but if everyone else dies off, there no reason they wouldn't just take over.
Amish fertility has fallen just as much as overall American fertility has.
"In the modern period, we can see that, from the early 1980s to 2000, Amish fertility had actually fallen way more than U.S. TFR [Total Fertility Rate] on the whole. Then it spiked in the late 2000s, and has fallen since."
There's a reason why religions exist. If they didn't increase the fitness of their adherents, they'd die out rather quickly. We may get caught off guard by shifting demographics and a decline in secular value systems. There are many religions which preach the 'fertility gospel' in one form or another. If the religion is effective in keeping the new generations devout, and that is an important question, we're going to have a population explosion.
The Shakers, a Christian sect that enforced complete celibacy (pretty much the definition of decreased fitness) was founded in 1747 and apparently continues to this day  (although from the looks of it, it probably won't last another 50 years).
That being said, I largely agree with your point. Religions that make up substantial portions of society are probably beneficial for the fitness of their members.
I know very little about the Amish, except that they eschew certain kinds of technology (sort of - Amish tend to be fragmented over this issue) and somewhat insular.
I can confidently say: no one knows what 200 years will do to Amish culture.
Edit: Although, there's also a change that we're just measuring productivity incorrectly right now, and not correctly taking into account the way the online economy works.
1) Our standards for products have grown exponentially. It probably does take more labour-hours to produce, say, a mid-range car today than it did in 1980, but that car does unbelievably more than the 1980 model did. Everything in it is controlled and monitored by software. It has navigation and safety and vehicle control and convenience and entertainment features beyond anything you could get even 5 years ago. It'd be astounding if it didn't take more time to build.
2) Wages in real terms haven't grown significantly in a long time. This translates to labour hours being relatively cheap, so companies can spend more hours on their products for the same R&D budget.
If the population globally is shrinking, that means the likelihood that any given town will increase in size is also shrinking. At first, this might look like the real estate prices across the board will decrease but I don’t think so. I think that when people factor in that the town they are in currently will not increase in size they look at cities that already have good markets and move there instead, driving up the prices of already established cities.
This is basically what is already happening in European countries with falling birth rates.
Being only slightly facetious, but if everyone had no more than one child, that leaves a lot more time in which to invent stuff. And true, over time there will be fewer people doing the inventing, but a world with ~a billion people in it still managed to invent flight, and one with billions fewer than today still got to the Moon.
Previously population growth was essentially a prerequisite for specialization in order to but well that has been broken for a while now.
Education, research funding, trade, cross pollination of ideas and similiar would have more of an influence but population growty does drive some.
If there is no growth even in such hypothetical extremes as a fixed population sustainable everything model then society is fundamentally doing things very wrong. Because you have global workforces working at things and nobody is learning to do anything better. A newbie having the exact same productivity as a veteran. In every field. That is deeply contrary to the state of being of everything and implies truly epic levels of mismanagement.
This paper on the economic consequences is also interesting. It popped up on various economics blogs when it came out.
"The significant problems we have cannot be solved at the same level of thinking with which we created them" --Einstein
The assumptions made don't even render a world that looks remotely similar to what we have, and that abstracting away of messy complexity actually makes the central characteristics of the problem harder to wrap your head around, even if it does make it easier to reframe into a paper that'd look good in an academic journal.
Case in point:
You don't need higher math to understand that human beings are fundamentally lossy in nature. Perfect replication of the information required to sustain the current cumulative knowledge level doesn't happen because there is no guarantee that any one person that knows a thing can successfully communicate it to someone else in a way that can be understood, and that in the process of doing so, that that information isn't mutated in such a manner that something important isn't lost. Children amuse themselves with this phenomena all the time. It's called a game of "Telephone".
Given an acknowledgement of this, the tendency for population decline to result in problems for a world that has been architected around the guarantee of population and economic growth is immediately intuitive.
As death removes older generations, the knowledge they had and failed to clearly replicate dies with them. Each new member of the population birthed in is a new crank on the slot machine of information propagation. Their life circumstances might allow them to understand that bit of arcane knowledge that no one else was able to do anything with because it didn't make sense to them because the constellation of shared lived experience between communicator and communicated necessary for comprehension wasn't there. New idea formulation, or old idea reformulation and propagation becomes reliable and less likely to snowball out of control to irrevocable loss as long as you keep throwing new blood at it.
If there is no new blood though, the numbers quickly begin to favor the life experiences required to underpin all the minutiae to sustain the corpus of knowledge as is not reoccurring in total across the entire breadth of the population, and you start to find your smaller remaining population further and further isolated from the practical experiences that made the linguistic representations of knowledge written down understandable. The knowledge then becomes useless, a dependency in the infrastructure that enables efficient physical completion of labor is lost, thus your population's output of tasks done per unit time drops, thus more work must be done just to keep things running, and so on and so forth until basic principles are again reformulated, and efficiencies from a chance rediscovery of the necessary experience underpinning a lynchpin technology can be realized again.
Just as information transfer is lossy, so is physical labor. If you have 1 million tasks that must be done in a day to maintain a stable level of output, and you decrease the number of agents available to do the tasks, the math simply works out that more work has to be done per agent to maintain output in a steady state, and we all know that the work output of a human being isn't trivially scaled up without ballooning the prerequisite knowledge required to do the task (I.e. skills at using tools, skills to teach the skills to use the tools, the tools to make the tools, the skills to operate the tools to make the tools, etc...) all of which themselves become tasks added on to the overall workload of your dwindling population who are working harder and harder to maintain the highest level of output possible.
The other issue not even touched on is the desirability of continued high growth regimes in the presence of a near tipping-point constraint violation to which a remediary measure has not been formulated. I.e. Excess carbon footprint. If you stay in your high growth regime in a wager to get that innovation faster from a new member, you're still templating your current footprint of resource use, and accelerating reaching your tipping point, with no guarantee you'll find it in time. Decline is a natural outcome in an organism facing this type of environmental dynamic constraint to buy time for other (in this paper, unrepresented, but which one can represent as decreased demand to output more of the destabilizing factor by your population, or natural processes operating to free up buffer space by things like carbon recapture and sequestration) processes time to shift the dynamics back in favor of supporting a new high growth regime.
I have the utmost respect for those that can trivially converse in the higher maths; I'll admit I had to crack open some books to understand what the heck they were getting at and whether it even made sense. I draw the line though where doing your analysis as they did takes you right out of reality into the atrophied realm of post-facto narrativization.
Those equations are meaningless to most readers, whereas putting things in terms of tasks to be completed, and characterizing overall knowledge level management as what it is, a bunch of overhead tasks draws the same Senate picture that it took them mucking around in control theory to even tangentially articulate. It started a conversation yes, but by constraining it to the realm of finance and economics, and leaving out the rest of the world you run afoul of that great aphorism that "problems cannot be solved with the same level of thinking that created them in the first place", which is exactly what this paper appears to be an example of doing.