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.

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.

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.

“The only problem is…get replaced”

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

It’s people. Soylent green is made out of people.

“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.

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

According to the New York times, it’s a “disaster”.

http://www.nytimes.com
“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”

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”

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

No, it’s a “demographic time bomb”

news.bbc.co.uk
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.”

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

No, its “Demographic Doom”.

http://www.ibtimes.com
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.

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

No, it will “create havoc”

Bloomburg Business week:
http://www.businessweek.com/lifestyle/content/aug2010/bw20100812_825983.htm
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”

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

No, its a “demographic catastrophe”

The Washington Post:
http://www.washingtonpost.com/wp-dyn/content/article/2008/05/05/AR2008050502224.html
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”

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

No, its a “demographic apocalypse”

International Business Times
http://www.ibtimes.com/japans-demographic-doom-214188
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. “

HIDENORI SAKANAKA:
http://online.wsj.com/article/SB10001424052702303714704576384841676111236.html
“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.”