It looks very much as though we are in total agreement, Olduvai.

>>Pericles, look up "demographic transition"... At some point in time (if you believe that we can't go on growing forever *). We will get a population pyramid like that of stage 4 in the reference I have provided.<<

Which clearly shows that there is a bulge of oldies at the top and a shortage of kiddies at the bottom.

Since we agree, perhaps you would try your hand at completing the equation I offered earlier - "with lots of oldies, no kiddies, and no net immigration, the economy would thrive, because...?"

And Stage 4 depicts contraction, by the way, not...

>>...death rate and birth rate in rough equilibrium.<<

It is of course only a model. A model that in fact freely confesses "the DTM is only a suggestion about the future population levels of a country. It is not a prediction."

One of the obvious reasons for their caution is that "although this model predicts ever decreasing fertility rates, recent data show that beyond a certain level of development fertility rates increase again."

So we should probably expect a variation on the model (Stage 4.5, perhaps?) to appear soon, that will lead you to a position of even greater certainty, I expect.

>>Also why the focus on Japan? Russia's population has sunk since the end of the USSR by 6 million. It would not be my choice of place to live, but they are still a viable entity.<<

From the same source:

"Russia has been undergoing a unique demographic transition since the 1980s; observers call it a "demographic catastrophe": the number of deaths exceeds the number of births, life expectancy is drastically decreasing and the number of suicides has increased."

That would add a subtle new shade of meaning to the concept of a "viable entity" to most people, I suspect.

Russia's economy is doing fine. It is in no way a failed state. As I said no one is starving and they did not revert to the stone age because their population fell. I don't know why this change was called a demographic catastrophe.

A catastrophe to me is defined by systemic failure. I would call the fall in population and the loss of many technologies, culture and knowledge that corresponded to the collapse of the Roman Empire and the beginning of The Dark Ages as a demographic catastrophe. Most Russians went through the transition without too much pain. See the writings of Dmitiri Orlov for detail.

Infinite growth with finite resources is a mathematical impossibility. Anybody to stupid to grasp this fact should be required by law to take a remedial mathematics class; those who still don't get it should be taken out back and shot.

Whether more or less population is the aim or not, it will not matter.
Nature is about to impose her solution.
The green revolution has resulted in the farmers using increased
fertiliser and the soil has become infertile in India, according to a
report this morning.

Increasing food shortages are alarming the UN Food organisation and
the resulting increases in prices will result in malnutrition and
starvation.

Couple all that with energy descent and larger populations are not a
relevant discussion. This discussion should be how to manage a mass
movement of populations together with sudden falls in population.

Will starving populations be able to move more than a few hundred Km ?
Certainly they won't be able to pay people smugglers, but will there
be enough with some money that want to get out asap ?
Should we pull up the drawbridge ?

These are the population questions, not can we have a population of
30 or 50 million.

“These are the population questions, not can we have a population of
30 or 50 million.”
Bazz, if we are going to have the train wreck you describe, it would seem reasonable to stop pushing more people onto that train, as is being done by our Government.

Yes indeed Colinsett.
It seems odd that we continually worry about the wrong problem.
We worry about global warming when the real problem is a fall in energy
availability. The IPCC still has not rerun its projections, as far as I
can tell, with the new available fossil fuel figures.

The real problem is what should we do when the food shortage gets
really severe, the problem will not be how we stop the boats but to
where we tow them back. Of course their ships may be too big to tow so
it would require armed boarding parties.

I wonder if any politicians would be politically courageous enough to
consider these things. Judging by their cowardice to discuss oil
depletion with the public I guess not.