Skip to content
November 30, 2012 / JayMan

Why sub-replacement fertility is not necessarily all that bad

From Tokyo: The World’s Most Uncomfortable Commute:


Previously: Another tale of two maps


Leave a Comment
  1. Curious Observer / Nov 30 2012 2:36 PM

    Add in resource depletion, pollution, and the increasing obsolescence of human workers, and it seems pretty clear that negative population growth is probably a net benefit to society. The only problem is when the sub-replacement fertility folks get replaced by higher fertility folks. The Japanese have gotten around this problem by the simple expedient (which hasn’t occurred to most of our elites in the US), of not letting in a lot of fast-breeding foreigners.

    • JayMan / Nov 30 2012 2:43 PM

      Precisely. Despite calls by outsiders for them to (very much against their own interests) let foreigners in.

    • Toad / Dec 5 2012 3:15 PM

      “The only problem is…get replaced”

      Well, just one minor drawback to a plan that has many benefits.

    • Toad / Dec 5 2012 3:39 PM

      “The only problem is when the sub-replacement fertility folks get replaced by higher fertility folks.”

      So, in the end, the population density doesn’t actually decrease because people flow in from the outside to fill up the empty space created.

      And you are still being ramrodded into the subway, but now with a bunch of immigrants.

    • JayMan / Dec 5 2012 6:45 PM


  2. asdf / Nov 30 2012 4:14 PM

    The Japanese are very strong racists though. They also believe in community values beyond individual good. Ironically all of those things are undercut by the liberal way of life.

    Anyway, I don’t think high TFR is a problem in America where there is tons of land for new people. The case is a lot stronger in Asia.

  3. Handle / Nov 30 2012 11:19 PM

    The Solow model says that the population growth rate and the per-capita productivity rate are inversely related. The faster the population grows, the more the productivity-enhancing capital accumulated in the previous generation has to be spread around. Depreciation, low-savings rates (and/or malinvestment), and high population growth can overwhelm such capital accumulation. It can even overwhelm technological progress, especially in an era of real-productivity-stagnation. It can either keep countries poor or even make them poorer, especially if there is some critical local resource the supply of which is highly inelastic – like arable land and water in the Sahara.

    In fact, I seem to recall reading somewhere about counterfactual impressive growth-rates that the “trapped” countries would have experienced had they adopted more modern fertility rates instead of experiencing exploding populations over the last century. And you can ask the reverse question too – how much growth in some countries was attributable to their declining population rates?

    As a thought experiment – imagine that half the human population – proportionately in every way imaginable, were to disappear, but all the resources and capital left behind? Would the world be a better or worse place to live in for the average person after that (after all the grieving, of course)? I’d argue vastly better. Now, if you kept halving, there’s a point at which things would get worse, but what significant contemporary economies of scale depend on 7 billion humans instead of 3.5 billion? (There are some marginal positive effects, by definition, certain low-frequency niche markets can only survive or flourish at some large critical mass, but the analysis is complex.)

    So the demographics question is really one about immigration and ethnic replacement, idiocracy-like dysgenics, the future of the welfare state – especially with regard to generational transfers from young to old, and relative aggregate economic and military power of nations in competition with each other for resources and influence. But all of those things must be balanced against what are some pretty clear and well understood advantages of a stable or declining population.

  4. Toad / Dec 5 2012 3:52 PM

    “Why sub-replacement fertility is not necessarily all that bad”

    According to the New York times, it’s a “disaster”.
    “Insular Japan Needs, but Resists, Immigration

    its population shrivels and the slow fade of its economy turns into a rout.

    the present population of 120 million will be cut in half

    the only hope for stabilizing the population is large-scale immigration

    a scarcity of workers and falling demand … collapse of the pension system as the tax base shrinks

    To stave off such a disaster, Japan would need 17 million new immigrants”

  5. Toad / Dec 5 2012 4:12 PM

    No, it’s a “population crisis”.

    Only immigrants can save Japan

    Hidenori Sakanaka, former head of the ministry’s Tokyo Immigration Bureau [said:]

    Japan, is on the brink of collapse.

    they live in an era of a severe population crisis”

  6. Toad / Dec 5 2012 4:22 PM

    “Why sub-replacement fertility is not necessarily all that bad”

    No, it’s a “demographic time bomb”
    Japan eyes demographic time bomb
    “an issue looming ever larger for Japanese society.

    So what are the implications for Japan?
    …a shortage of workers in the future.
    …companies will soon be struggling to fill jobs
    …fewer taxpayers and so less revenue
    …Schools are closing, buses are running less often.”

  7. Toad / Dec 5 2012 4:30 PM

    “Why sub-replacement fertility is not necessarily all that bad”

    No, its “Demographic Doom”.
    Japan’s Demographic Doom: Tokyo’s Population Will Be Cut In Half Over Next Century
    “Japan’s future demographic crisis has been highlighted by a municipal government report citing that the population of the capital city of Tokyo will be cut by half over the next 90 years.

    [Tokyo] city’s population will plunge
    …Such dire numbers spell doom
    …local governments will face severe financial strains
    …nation’s population will plummet
    …The easiest solution would appear be [for Japan] to allow immigration immediately
    …Japan’s demographic problems
    …paints a grim picture for Japan’s future.

  8. Toad / Dec 5 2012 4:39 PM

    “Why sub-replacement fertility is not necessarily all that bad”

    No, it will “create havoc”

    Bloomburg Business week:
    Shrinking Societies: The Other Population Crisis
    “the number of older persons in the world will exceed the number of young for the first time in history…The imbalance will create havoc in the pension systems”

  9. Toad / Dec 5 2012 4:49 PM

    “Why sub-replacement fertility is not necessarily all that bad”

    No, its a “demographic catastrophe”

    The Washington Post:
    Japan Steadily Becoming a Land Of Few Children
    “For this is the land of disappearing children and a slow-motion demographic catastrophe that is without precedent in the developed world.”

    The economic and social consequences of these trends are difficult to overstate.
    …economic growth will slow to zero”

  10. Toad / Dec 5 2012 5:06 PM

    “Why sub-replacement fertility is not necessarily all that bad”

    No, its a “demographic apocalypse”

    International Business Times
    Japan’s Demographic Doom
    “Japan is facing a demographic nightmare that portends a doomsday scenario for its future.

    Peter H. Liotta PhD is the author of The Real Population Bomb

    [Q] What can Japan do to prevent this demographic apocalypse?
    [A] allow immigration immediately. “

  11. Toad / Dec 5 2012 5:29 PM

    “Population is a central problem confronting Japan.
    …it is simply a matter of time before…the very ability of people to make a living will all collapse under the…pressures of…declines in…population.
    …The only solution is to import more workers.

    Lack of fresh faces makes the country seem increasingly sterile.

    stake its very survival on accepting people elsewhere in the world as its brethren, and transforming itself into a much more multicultural, diverse society.”

  12. Anonymous / Feb 27 2018 5:24 AM

    Sorry to flog a dead horse (old thread), but I just wanted to chime in. I think in such a severe situation as Japan’s they probably should open up to SOME immigration, but it needs to be the right kind of course. IMO America provides a great example of what works, and what doesn’t. There were tensions between different types of Europeans back in the day… But the melting pot worked, because we were otherwise so similar, and after one interbreeding it’s near impossible to tell who is Irish/Italian/German/English etc. Also, if it had gone slower and not in such big waves, even what little tension there was could have been greatly reduced. Obviously other immigrants have been a major pain in the rear and completely useless/counterproductive. What works: Ethnically/culturally similarish people to the main group, but not those completely different that can never fit in and integrate.

    IMO Japan should open themselves up to immigration from other high IQ Asian countries, specifically high education individuals. But perhaps even “working class” folks if their labor demands seem to require it. China, Korea, Taiwan are obvious… But perhaps, since selecting specifically from high education (likely high IQ) people they could also allow in other Asians as well.

    From what happened in America I would feel 99% confident that inside of 2ish generations all the Japanese/Chinese hybrids would slide right into adopting Japanese social norms, nobody would even be able to spot who was who in a crowd (which IMO is important due to human affinity for people that look like themselves), and they would of course avert the worst of their demographic issues. Clearly they should also try to change the society to encourage more children with policies Jay discusses in other posts on here as well. But 10-15 million immigrants over 20-30 years could keep them stable, but probably allow for a pretty smooth integration.

    China of course is the country that’s REALLY screwed, because their population is so huge there simply isn’t anywhere to poach people from. But most high value/wealth nations could surely keep their populations stable with the right kind of immigrants that can actually integrate.

    • JayMan / Feb 27 2018 5:42 AM

      Japan has 127 million people in a country the size of California. How are they in a “severe situation”?

    • Anonymous / Feb 27 2018 10:15 AM

      Well, I know you already know all this, but for any future readers who don’t know some of this stuff: More or less to cushion the glide down to a lower population.

      The problem isn’t the total number of people, but the unbalanced nature of too large a number of retired people to working age people. They have ponzi scheme social programs like most 1st world countries, but even without that it would be a huge financial burden, and have other social consequences. Adding in some properly qualified people in the prime of their working lives can help with most of the related issues.

      On the “overpopulated for an island of its size” thing, that’s kind of a yes and no situation… I actually read a very interesting article about how the suburbs of Tokyo are in fact clearing out. They got built up during their baby boom, and now there are many houses just sitting there rotting because there is nobody to live in them. In the countryside proper it is quite wide open still.

      It’s like people who say the USA is overpopulated… We’re not really, we’ve just crammed into fewer and fewer areas. Places like the Southwest in the US have water issues, and maybe the heart of Tokyo is still too packed too, but most of the rest of the country is not overly so from what I have read.

      I’m not saying Japan should shoot for bumping up their population to 200 million or anything crazy. Even if they added a more modest 5 million high education East Asian immigrants over 20 years, they would likely integrate well, and it would really soften the financial blow they’re taking as a nation with their lopsided demographics. I also don’t think it would damage their culture much/at all if it was slow and steady and full integration was expected.

      I’m totally cool with peaceful ethno-nationalism, but when there are practical solutions that probably won’t have any real big downsides, immigration is fine. If Sweden was taking in German immigrants instead of Muslims, I don’t think they’d have much in the way of integration problems, even if there are some minute genetic/cultural differences between the two. Ya know?

    • JayMan / Feb 27 2018 10:39 AM

      Or maybe they should let fertility rise on its own as the country depopulates.

    • Anonymous / Feb 28 2018 11:32 AM

      Perhaps they should! But softening the blow with a small, and easily made to be eugenic, immigration policy wouldn’t exactly be horrible.

      From the reading I have done over the years their birthrate issue is far more severe than saaay the one we have in the USA. Some European countries have comparably large issues, but Japan is about the worst. In the USA I think our situation may well sort itself out because it is so much less severe to begin with, but I’m still not against the right kind of high skilled immigration even here.

      In Japan it is a lot more acute of an issue. It won’t be the end of the world if they never do decide to allow immigrants, BUT it equally wouldn’t be the end of the world if they did allow in good immigrants in reasonable numbers.

      I do still have my doubts that birth rates will bounce back anytime in the near future. I think the legal and social issues between the sexes are every bit as big a part of the problem as finances, if not in fact far bigger.

      There is a 99.9% chance I would have been married with children 50 or 75 years ago by my age, but I am not now. This is mostly because I am smart enough to know I need to find a 1 in a million type of woman to marry nowadays (okay, maybe only 1 in a thousand when considering personal compatibility and looks!) to avoid the many problems most men end up facing, such as divorce, having your financial life ruined, your kids barred from seeing you, etc.

      Finances are a small part of why I have put off getting more serious about finding “the one,” but I’ve always made far more than the national average, so would have gladly done it if I’d actually met a worthy woman. For the guy who actually thinks things through, instead of going with his emotions telling him it’s a great idea to marry the hot crazy chick, there are almost no marriageable women out there nowadays. 100 years ago most women were acceptable, because of the rules society had in place to bind both men and women and force them to “do the right thing.”

      I’ve only ever dated one woman that even possibly would have been a sane choice for me to make. Unfortunately she had a quirk or two I realized would be issues long term, wasn’t quite pretty enough (she was pretty, but not my type), and was too short/maybe not quite bright enough for breeding purposes. Nowadays if you have any real standards it’s tough even for guys that do relatively well with women like me. Alternatively I’ve known tons of women who met all the criteria IF I didn’t have to worry about getting divorced and having my life ruined by them, as it would have been back in the day. Until that stuff changes, those issues will always impact birth rates IMO.

      So if birthrates don’t ever bounce back, I wouldn’t be surprised. The above is less of an issue in the east as I understand it, because they’re still more traditional than the west, but they have a bit of all of our modern western issues as well.

    • JayMan / Feb 28 2018 11:38 AM

      But the thing you haven’t made clear: for what reason is the current low fertility rate such a pressing issue that they need to increase immigration?

    • Anonymous / Feb 28 2018 12:37 PM

      Well I did mention some bits briefly above, but the often mentioned economic issues mainly. An abrupt economic shrinking (potentially in absolute as well as per capita terms when the fullest effects come into play) brings a lot of problems. Also the ponzi scheme nature of most 1st world governments entitlement programs. I am of course for changing such entitlement programs to be eliminated, or at least made more sustainable, but either of those things is far harder with fewer productive workers and more elderly. For instance, Social Security would still be solvent if we still had the same demographic mix and TFR as we did in decades past. As it stands now we’re going to have to slash the hell out of payments, or increase taxes, which of course economically drags down all the current payers further. Probably both will need to happen.

      To be clear, I DO NOT think the issues are as severe as many mainstream politicians make it out to be. The whole “We HAVE TO import millions of immigrants, no matter their skills, to keep things from collapsing!!!” argument is overblown. But there is truth to the general idea, in that there will be pains if the absolute population shrinks too abruptly.

      I don’t think shrinking population is all bad for reasons you mention in other posts on this site, but if it happens too sharply it will be more painful. Hence a slow glide down is preferable. In the USA our TFR is close enough to replacement, even for many economically productive groups, that we could probably go through the transition without much pain. But places with 1.6-1.7 or so and lower… That’s a fast shrinking of the population. Some countries are set to nearly halve their populations more or less in a single generation, that’s a SEVERE issue in a way that a 1.9 or 2.0 TFR is not.

      And I suppose there is the whole “being replaced” and/or outgunned thing. If some countries keep up their populations more than others (without destroying their cultures, because I think you can do both if done right), and others don’t, the ones that don’t will become relatively weaker and easier to push around etc. Japan is one of the major players in the world today in almost all arenas. If they have a population of 60 something million in a few decades, they will lose stature in the world compared to others that don’t. Being big for biggnesses sake isn’t everything, but having some weight to throw around to make sure you don’t get bullied is not a bad thing either in the real world.

    • JayMan / Feb 28 2018 2:00 PM

      I seriously doubt their population will decline that much. The Japanese are all right.


  1. Finland & Japan « JayMan's Blog
  2. Me… « JayMan's Blog
  3. A Tale of Three Maps | JayMan's Blog
  4. Fertility and Happiness: A Global Perspetive | JayMan's Blog
  5. 100 Blog Posts – A Reflection on HBD Blogging And What Lies Ahead | JayMan's Blog

Comments are welcome and encouraged. Comments DO NOT require name or email. Your very first comment must be approved by me. Be civil and respectful. NO personal attacks against myself or another commenter. Also, NO sock puppetry. If you assert a claim, please be prepared to support it with evidence upon request. Thank you!

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: