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Re: New Scientist spreading Malthusian gloom again

Perhaps some of the contributors here can tell me what the maximum tolerable human population is? At what point does the human population's exponential growth have to stop before we do actually run out of food (which is probably well beyond the point at which population increase stops improving our quality of life and starts diminishing it - just go to London if you don't believe this is possible)? The answer is below infinity, so what is it?

It might well be premature of NS to call the "top of the market" now, and they might be calling it for the wrong reasons, but those who think we can have an unlimited population, and think we have unlimited oil, etc, must believe in a flat earth, for only on a flat and infinitely broad and deep earth could this be the tcase.

So, once again, where is the limit?

Re: Re: New Scientist spreading Malthusian gloom again

I did hear on Radio 4 a while ago that to have UK standard of living would require about 3 planet earth's worth of resources. To have US standard about 5. Problem with this is it doesn't take account of technological innovation - without the farming methods used in industrialised countries we would have "topped out" years ago. The US figure is dubious because a lot of people live in utterly awful conditions and making their standard of living worthwhile might not be as hard as you'd think. You can only sail one yacht at a time.

It's one of those questions that can't be answered easily because of technological innovation. I believe, because humans have overcome previous barriers without even realising they were there, that it's a long way off. We could still expand off planet if we can get the technology reliable and cheap enough.

Population is clustered in places like London and it gives you a false perspective. I live in North West England and we don't see the shortages and hassle and broken Victorian infrastructure (not as much anyway). Most of the USA and China etc. are open space.

According to Malthus we are already dead, because his assumptions were that everything else remains in a steady state. Every time there is an economic slowdown or crash there are too many people suddenly - it's code for too many poor people, possibly of the wrong skin colour. Do you remember that the Biafran crisis (late 60's?) was blamed on overpopulation? Nope, it was a dirty war.

Instead of investing in ways that might help the poor and make the world the better place the Malthusian view allows the politicians off the hook while people starve.

This is my opinion. I'm happy for people to prove me wrong.

Re: New Scientist spreading Malthusian gloom again

Well, on creaking Victorian infrastructure, driving down the A6 in Salford last week was the nightmare it has always been. Cities don't necessarily give one a false perspective. London has to have rather a lot of not-London to feed it, provide its water and bury its dead in. Similarly not-London needs London to provide whatever it is that London provides for the world, investment banks or something like that.

My cynicism aside, the shortcomings of the assumptions underlying Malthusianism will still not permit the planet to support an infinite population in even the most abject poverty. At some point we will have a near as dammnit complete maximal sum total of innovation, efficiency in the economy, productivity etcetera. We all know profits (surplus productivity) tend to zero. When that has happened, with a completely developed earth (which none of us really want), you could draw a graph of population (X axis) against wealth per individual. The graph will rise steeply from zero, flatten out, and then fall gradually, I guess linearly at first and then exponentially, until it returns to a point at which there is only just enough wealth per person for mere survival. That defines your maximum population. I don't know if that point is one billon, ten billion, or ten thousand billion, but infinity it ain't. Malthus was ultimately right, even if we take the most optimistic assumption about economic productivity as opposed to the most pessimistic.

Re: Re: New Scientist spreading Malthusian gloom again

I agree - I'm not saying that there is no upper bound, more that the hysterical innumerate article that NS put forward isn't a sensible way to talk about it.

It may be a long way off, or just round the corner, but it needs numerate and thoughtful people to look at it. Not some hysterical articles built around a "hockey-stick" curve with no axes explained.

Re: Re: Re: New Scientist spreading Malthusian gloom again

There is an upper bound, but it varies by the picosecond in response to the carrying capacity of the Earth. For instance, should there be a bumper harvest all over the human carrying capacity will increase. Likewise, should crops fail and stores be destroyed by disaster, the maximum supportable population will fall - probably dramatically. The same goes for all resources.
This is why all living organisms fill their boots in good times so as to have the best chances of a few surviving when things go **** up. This also provides the greatest variety of genetic profiles so that it is most likely that some will be "fitter" to survive, giving the variable rates of evolution we see in the record.
The Left-wing idea as exemplified in New Scientist is akin to that of the soviet planned economies whereby an omniscient government identifies the best sewing machine (for example) and then copies it in one enormous factory to avoid the wasteful duplication inherent in the free market. Since nothing in nature does this, it's a fair bet that it'll never work.
Any living organism grows or dies, it's that simple.

Re: New Scientist spreading Malthusian gloom again

The theory that developed societies tend to reduce population growth and start to decline seems to me to have some validity.

Of the families I can think of in a social sphere only 3 have more than 2 children and in two cases twins are a factor. The road in which I live has mostly mature people (only 2 houses are of evident breeding age and have 3 children between them so far.) No one has more than 2 children and several, including couples, have none. A number of my Wife's long term female friends - people of similar age whom she worked with years ago in her 20s - have never had children.

So it seems to me that the theory is probably correct and that there is eventual potential for improved development of societies to lead to reduced birth rates.

The only problem in reaching that point is the attendant longevity related to better health that goes with the improved development which would suggest a population bubble would be likely.

Of course, thinking darkly, one might observe that if the populations numbers were indeed to become a real and threatening problem then of all the 'issues' that humanity faces it is probably the one that could and would be resolved, though probably rather messily and unpredictably.

Which leads me to wonder how accurate the estimates of world populations are.

Any thoughts on that anyone?


Grant

Re: New Scientist spreading Malthusian gloom again === For Mal-adjusted People!

Malthusian Gloom --- For Mal-adjusted People!

Francis,

I do heartily agree with you about world population sustainability. Malthusian gloom is for maladjusted people. Arrhenius gets a 'bee in his bonnet' and gets ignored by his contemporaries, but AGW's dig around in ancient history to find some well known name to plagiarise, thus lending support (in the ill-educated mind) to their crazy notions about CO2, and enviro nuts do the same with Malthus. Of course, these ancients can't answer back or have their notions scientifically tested, so they think they are on safe ground?

JamesV is obviously a supporter of these notions, otherwise, how could he have the nerve to demand of the Forum that we have any responsibility to respond to his cynicism and rhetoric? Discussing limits to population growth and sustainability of food resource are non-questions, and about as useful as trying to out-guess the forces of evolution. Anyone who persists with this stupid haranguing is obviously maladjusted and should be 'put in the stocks'! Or maybe we should treat them with pity: notice that it only comes from 'educated' people, which does lend credence to the observation that some people have been educated beyond their intelligence quotient.

I have an abiding faith in humanity, simply because we possess the unique asset of an abstract brain which gives us the power of visualisation, enabling anyone to contemplate what may be; and to act on that contemplation: thus creativity is born. ---
It is because we have this power of contemplation that we can react to, and amend our personal environment to suit our best chances of survival, and the Survival Instinct is paramount, it is 'hard wired' through our genetic structure.

Where this survival instinct is most manifest, is in the business of pro-creation, and for every species on this planet there is a norm which is built in to its bio-chemistry. And this norm is sustained by the simplest of mechanisms: pain. For every species, giving birth is a very painful, exhausting, traumatic process; not to be repeated unless species survival is threatened. --- For these reasons, it is scientifically absurd to apply an exponential factor to population growth, simply because we do not have the power to override the forces of evolution and our 'species survival instinct', which must and does determine birth rates.

Notice the fact that much of the western world's birth rates are below replacement norms, and the norm for humans is 2 to 3 at this point in time. To me, it is apparent that nature is at work here; our females, to whom giving birth is a painful and sometimes life threatening process are sensing that our population is a little too high. Their instincts tell them that they do not need to take unnecessary risks, so birth rates will stay low until death rates balance the equation. Or, if over-much immigration continues, indigenous birth rates could fall further to compensate.

Bring the standard of life in the undeveloped countries up to our levels, and the females of those countries will be able to take a much needed rest from the strife of child bearing. --- Malthus needed an education, not privilege!

David

Re: New Scientist spreading Malthusian gloom again

JamesV is obviously a supporter of these notions, otherwise, how could he have the nerve to demand of the Forum that we have any responsibility to respond to his cynicism and rhetoric? Discussing limits to population growth and sustainability of food resource are non-questions, and about as useful as trying to out-guess the forces of evolution.
=======

Feel free to tell me what the absolute maximum sustainable human population is. Any time will do. You may assume that future humanity has the capacity to harvest every single kilowatt-hour that falls on the planet from the sun, and the capacity to use this at 100% efficiency to provide for the minimal basic living standard for all humans and no more.

===
I have an abiding faith in humanity, simply because we possess the unique asset of an abstract brain which gives us the power of visualisation, enabling anyone to contemplate what may be; and to act on that contemplation: thus creativity is born. ---
It is because we have this power of contemplation that we can react to, and amend our personal environment to suit our best chances of survival, and the Survival Instinct is paramount, it is 'hard wired' through our genetic structure.
===

Humanity is indeed underrated, but it is also capable of overestimating its own ability to provide. People in poor parts of the world have lots of kids so that those kids can provide for them in their old age. Other people are religious and engaged in breeding wars with people of other religions or atheists. The evolutionary survival instinct always says "reproduce exponentially", the fittest will survive. The fittest in the case of humanity being the ones with the biggest sticks. There is an ugly counterbalance to our instinctive compassion for others, and it finds its most horrific expression at times of shortage of resources.

===
For every species, giving birth is a very painful, exhausting, traumatic process; not to be repeated unless species survival is threatened.
===

Most species aren't sentient enough to know where babies really come from. Come on, a lot of humans behave as if they don't! Clasically, all animal behaviour is driven by the "four F's", Feed, Fight, Flee, and Reproduce. Animals are not interested in their own survival - their genes are interested in their survival for as long as it takes to make as many copies as possible. Humans are little different in this regard, and are certainly unique in their ability to use contraception. Animals have sex because, like humans, they enjoy it. Anyone who thinks otherwise should take a walk in the country.


===
Notice the fact that much of the western world's birth rates are below replacement norms, and the norm for humans is 2 to 3 at this point in time. To me, it is apparent that nature is at work here; our females, to whom giving birth is a painful and sometimes life threatening process are sensing that our population is a little too high. Their instincts tell them that they do not need to take unnecessary risks, so birth rates will stay low until death rates balance the equation. Or, if over-much immigration continues, indigenous birth rates could fall further to compensate.

Bring the standard of life in the undeveloped countries up to our levels, and the females of those countries will be able to take a much needed rest from the strife of child bearing. --- Malthus needed an education, not privilege!
====

I think this is over analytical but it's clear that economic development goes hand-in-hand with a drastic reduction in the rate of population growth - the USA being something of an exception (I suspect that has something to do with the fact that it's the only seriously religious country in the developed world and making new souls for God to send to hell or fill his heaven with is a sacred duty, even to protestants.)

Let's try to bring on the economic development of the rest of the world before its population becomes truly unsustainable.