And that would be a stupid basis for policy, wouldn’t it? After all, there are real costs to population growth that my value judgment ignores.

Ditto, there are real costs to having an ever-rising median age and a shrinking population.

Mileage may vary on one’s estimate of the relative costs and benefits of population growth/population aging, and the corresponding burden that one is willing to bear to avoid them. But those costs are what the debate is about: I don’t immediately see why “a total lower population would be a good thing,” although it may, in fact, be. That’s the debate.

But it would be really useful, I think, if we left personal preferences out of it.

Otherwise I’ll be here yelling, “Build more Brooklyns! It’s a good place! Bring on a billion Americans! And I like teenagers!” while others will kvetch about “Traffic! And, like, ugly buildings! I like trees! Plus screw those goddamn teenagers and their noise!”

Boring as all get-out and intellectually-vacuous.

Kenneth Rogoff’s take avoids the generic bloviation which most of the “productivity miracle” apologists like to indulge in: “…together with a few sister “big box” stores (Target, Best Buy, and Home Depot), Wal-Mart accounts for roughly 50% of America’s much vaunted productivity growth edge over Europe during the last decade. Fifty percent! Similar advances in wholesaling supply chains account for another 25%! The notion that Americans have gotten better at everything while other rich countries have stood still is thus wildly misleading. The US productivity miracle and the emergence of Wal-Mart-style retailing are virtually synonymous…But I do have some reservations about the Wal-Mart model as a blueprint for global growth…Indeed, many Europeans, and others, will view… (the) video simulation of Wal-Mart’s spread as a horror film… The big question for Europeans is whether they can find ways to exploit some of the efficiency gains embodied by the Wal-Mart model without being overrun by it.”

If Rogoff is right, the “productivity miracle” in the US will (be about to) run its course.

Cowen for his part intones the well-known hosannahs: “(m)any stories can be told about why the US is gaining on Europe. Most plausibly they involve greater micro-productivity in R&D, higher education, and the use of information technology.”

But hey, “Europeans have to work harder at shopping”! That’s a way to put it, I guess.

Concerning the main topic of discussion of this thread, I think that the “demographic bears” are not addressing John’s point head on:”there are some big demographic dividends from declining birth rates, which may not have the same salience but are important nonetheless.” The housing issue is indeed important, as are the quite specific demographic trends in cities. It appears that the population of successful cities will in all likelihood remain stable or grow moderately, even if country totals fall. This should have some beneficial effects on productivity.

After all, it makes the strategic placement of those Wal-Marts easier…

One factor that has only been lightly touched upon in the general paean to growth is the environmental cost of that growth. Japan’s 1.29 birth rate has politicians claiming the absurd conclusion that the population will eventually reach zero. The fact is that Japan can feed at most (without crop failures or agricultural pestilence) 50-60 million people. I would argue that suggests an ideal maximum population of about 40 million. Even that figure represents an optimistic outlook, for the largest pre-industrial population of Japan was in the range of 20 million, with periodic famine not unknown. Since the present population is over 120 million, immigration to sustain population growth would only exacerbate the environmental overdraft that Japan’s economy represents (I suppose that would be offset to some degree by the amelioration of overpopulation of the Philippines or China). Some other nations will have to divert resources to feed Japan, which in turn must then overproduce energy-using manufactured goods to purchase these agricultural products, and fuel must be expended to transport the traded goods in both directions. Cheap petroleum-based energy has fueled this world trade growth (including feedstocks for manufactured goods, chemical fertilizers, energy for production and fuel for transportation). When we run out of oil, this trade system will face collapse. Countries that cannot feed themselves will face shortages, perhaps famine.
As much as I love my Bing Cherries from Washington, my avocados from Mexico, my blueberries from Canada and my wine from Australia, Chile, France and California, the system of world trade is tied together by a very slender, very fragile thread.
Since the political will to tackle the world problems of overpopulation and over-use of energy is lacking, extreme measures to curb growth will be needed. Perhaps the sense of foreboding among young people has as much to do with falling birth rates as tax policy. Or perhaps Gaia is telling anyone who will listen that this madness cannot go on.

@ed hugh, serial catowner: wouldn’t it be nice if the demography and sustainability folk got together? perhaps they would make beautiful music together, and either 2.1 or 1.4 babies, depending on who won the argument!

Further, back in February I remember talking to Ed in Barcelona, when he expounded his theories to me and I mentioned the distinction in evolutionary biology between r-selection and k-selection (r-selected species are generalists and reproduce rapidly; k-selected are specialised to a niche and reproduce slowly). Perhaps we are flipping from r to k? K certainly seems a better choice in the long run. Some of the Worldchanging/Bruce Sterling/Stewart Brand people have been talking about these concepts with regard to buildings for a long time.

To be sure, such a thing might happen, but middle and upper class families typically reckon just the opposite in the modern world- that fewer children optimize the resources for each child.

The falling productivity of the older worker, and their desire to leave the workforce, are myths, especially in an age of “power-everything”. Today, workers are marginalized in their late-40s, when they still have, typically, twenty years of productive ability.

Now, turning to the next error of Cowen, he fails to understand that the America we know has been built for a lifestyle that is soon to disapear. The portion of our GDP derived from commuting is not a strength, but a weakness. Adding a GPS to a car for drivers too dimwitted to find a pizza stand is not an improvement in “productivity”.

In any case, unless we make some changes soon, the world population will be about 10% of what it is today, but the population of Finland, Sweden and Canada will be much larger than they are today. And it won’t be because their condoms burst.

First I have to note that John Quiggin seems to see the problem from the Australian perspective. While in Australia the problems of ageing are not as pressing as in many European countries they still have introduced a number of pronatalistic policies. But, if economic and demographic problems in Australia are overblown then why have they introduced those measures? I wonder why JQ makes no mention of them.

As for Europe, that can be divided into two parts: NW Europe where birthrates recovered after the onset of the babydip in the 70´s to a more acceptable level of around 1.6-1.9 and the rest of Europe with a TFR below 1.5. I should point out that timing also plays a role. In Germany the TFR dropped to 1.4 in the mid 70´s and has since remained around that level, Spain and Italy dropped to even lower levels towards the end of the 80´s and in Eastern Europe in the 90´s. Why the duration of low fertility is important I´ll get to in a minute. Let´s just say that until now (2006) there has been no significant recovery in those countries.

So at what level becomes a low TFR a problem? A country that still has a decent birthrate, like 1.7 or higher (and combined with a population that is open towards immigration) will not have as much to fear from population ageing as a country under the 1.5 threshold. A TFR off 1.7 means that the next generation will be one fifth smaller, a TFR of 1.4 means that the next generation will be one third smaller, a TFR of 1.2 means two fifths smaller and so forth….

…and this is where the potential crisis lies. The dynamics of population decline mirror those of population increase: halving times mirror doubling times and population momentum can press downward as well as upward. At first this will result in population ageing and eventually will come population decline. Although actual decline can be offset by further increases in life expectancy.

Note the emphasis I place on generation. That means it takes a long time (25-30 years) before the first effects become truly apparent. The absolute birthrate can remain stable during that period if earlier cohorts are large enough but once the first cohort of the babydippers reaches maturity and they choose to have the same average number of children as their parents you enter a negative feedback loop. Germany is the country to watch for the moment because it´s the first country to have experienced low fertility for one generation. If current projections hold up Spain, Italy and Eastern Europe will join it towards 2010-2020.

“Tempus omnia revelat”

But my question is, why can’t we be as happy (and if we’re happy, who cares about GDP?) with a stable or declining population, as with an increasing one?

the rather distasteful nationalism and xenophobia often coming from Europe on such matters.

Isn’t there at least some of that going on in the U.S. as well? Especially since 9-11?

And how do the illegal immigrants fit into this picture?

that is my understanding as well. The US is niggardly with benefits, and low-paying jobs are easy to get. The reverse is generally the case in the EU.

What is “full membership”?