« Boris Cannot be Mayor | Main | John Prescott: Fu.....yes, you know what goes in there.... »
July 29, 2007
Niall Ferguson on Malthus
Interesting piece. However, it really doesn't do to use the UN population projections (9 billion by 2050) without discussing what happens then. The best place to see the interplay of policy and population is in fact the SRES, the economic models upon which the whole climate change thing is based. Whether we take these as predictive models, or as future scenarios with a back story to explain them, matters little.
There are a number of different stories told: some that population continues to rise, to 15 billion in 2100. Others that population falls back, to 7 billion at that date. The major difference between these two (A1 and A2 families) in the policy format is, roughly speaking, whether globalization increases or is curbed. For these economic modellers are aware of what all too few in the policy world are: that it is not availability or not of contraception which determines fertility rates. 90% of the changes in fertility come from changes in desired fertility. What changes this appears to be wealth (in its broadest sense). Longer life spans, decreasing child mortality, the education of women and the existence of alternatives, all these things that wealth buys, lead to a reduction in fertility rates. As they have in the industrialised world, to below replacement. As we assume they will, if, as and when other parts of the world become similarly wealthy. As, indeed, the A1 family of scenarios assumes the whole world will be in 2100, thus the drop in population.
Which leaves the neo-Malthusians with an interesting option. Let's say that population really is the biggest problem: we'll agree for the sake of argument. So, what should we do about it? Well, the biggest yet piece of economic modelling of the future says that we should be intensifying globalization. Get everybody rich and population will peak and then fall. We can always add a carbon tax or cap and trade on top if we should so wish.
One alternative is that A2 family, where we turn back, return to regional and smaller markets, where technology does not move swiftly between different societies. That's what gives us the 15 billion people in 2100.
So, Malthusians for globalization?
July 29, 2007 in Economics | Permalink
TrackBack
TrackBack URL for this entry:
https://www.typepad.com/services/trackback/6a00d8341c2d3e53ef00e3933183d58834
Listed below are links to weblogs that reference Niall Ferguson on Malthus:
Comments
Here is Isaac Asimov making a similar point to Ferguson's about the prospect of climate change limiting the scope for the Green Revolution to save us from a Malthusian fate:
"In the course of the last thiry years, when population has risen by 1.5*10^9, the food supply has managed to keep up ... But now weather is taking a turn for the worse ...".
You are ahead of me, I know, but the source is ("Natural History", April 1975, American Museum of Natural History).
Posted by: Alan Peakall | Jul 29, 2007 12:56:10 PM
Again you are pretending the SRES scenarios are predictions of the economic future. Your sole concession to the contrary reality is a disingenuous preface:
Whether we take these as predictive models, or as future scenarios with a back story to explain them, matters little.
If they are not "predictive models" then you cannot claim that
...the biggest yet piece of economic modelling of the future says that we should be intensifying globalization.
The SRES simply doesn't say this. You cannot use the SRES to assert that "intensifying globalization" will "get everybody rich". I have pointed out twice before that the SRES explicitly states the scenarios are not policy prescriptions, and declines to assign probabilities to their occurrence. I realise you might wish this were not so, but I find it baffling that a blog purportedly devoted to rational analysis would simply ignore inconvenient facts in this way.
Tim adds: I've not said they are policy prescriptions, have I? They are descriptions, however, of the outcomes of certain policies: or, if you prefer to work the other way around, explanations of how we got to 7 billion or 15 billion people.
Further, that no probabilities are ascribed to the 40 scenarios makes no difference at all to the underlying stories of the four families. There is still a logical connection between if we do "this" then this will result and if we do "that" then that will result: even if we don't know the probability of our doing either this or that.
Posted by: StuartA | Jul 29, 2007 5:05:05 PM
Tim,
What's 'globalisation'?
I've seen four different definitions of that word.
Tim adds: I take it to mean the increased integration of the world's markets as a result of both technological and political changes.
Posted by: Martin | Jul 29, 2007 5:38:42 PM
Tim,
That's sort of a fifth.
'Political changes' - I don't remember ever being asked to vote for political changes leading to increased integration of the world's markets. Do you know if it's ever been in any party's manifesto?
And wouldn't you agree that if such a policy had been implemented without mandate, then that would be tyranny? Or treason?
Tim adds: Err. the collapse of the Soviet Union, the internal changes in China, the political changes in India: these are political changes which have all contributed to globalisation under my definition. No, none of them are tyrrany nor treason: the opposite in fact.
Posted by: Martin | Jul 29, 2007 8:35:31 PM
Er...
"Err. the collapse of the Soviet Union, the internal changes in China, the political changes in India: these are political changes which have all contributed to globalisation under my definition."
Err, all well and good; however, just what do any of these things have to do with us?
I was referring to British policy. Has any mandate for 'globalisation' ever been sought from us? I don't think so, but we're still told it's happening.
That is the tyranny/treason to which I was referring.
Tim adds: I realise that. But none of those other people need our permission now, do they? So it'll happen whether we are asked or not.
Posted by: Martin | Jul 29, 2007 9:33:19 PM
I've not said they are policy prescriptions, have I?
You have taken them to be predictions, which they are not. The SRES was not a prospectus for economic development; it was a collection of possible economic scenarios designed to provide inputs to climate models.
They are descriptions, however, of the outcomes of certain policies
No they are not. Not even when you say it for the tenth time. If the SRES stated that following certain policies guaranteed certain economic outcomes it would be a bizarre document, given its avowed purpose. As it is, the SRES did nothing of the sort.
Posted by: StuartA | Jul 29, 2007 10:40:37 PM
'What are scenarios and what is their purpose?
Future greenhouse gas (GHG) emissions are the product of very complex dynamic systems, determined by driving forces such as demographic development, socio-economic development, and technological change. Their future evolution is highly uncertain. Scenarios are alternative images of how the future might unfold and are an appropriate tool with which to analyze how driving forces may influence future emission outcomes and to assess the associated uncertainties. They assist in climate change analysis, including climate modeling and the assessment of impacts, adaptation, and mitigation. The possibility that any single emissions path will occur as described in scenarios is highly uncertain.'
For StuartA,
From the Summary for Policymakers, of the report, I read it that they are predicting a set of outcomes from a set of actions. They indicate it is all speculative and deeply uncertain, but they are indicating causality. I do not understand what your trying to say ?
I may well be thick though.
Posted by: Gengee | Jul 30, 2007 6:44:48 AM
Tim,
"I realise that. But none of those other people need our permission now, do they? So it'll happen whether we are asked or not."
Hmmm....
Where, then, is the line drawn? I'm as committed an EU-phobe as your goodself. It seems to be the case that further political integration of the Continent will take place 'whether we are asked or not'. We find this outrageous - so what appears to your passivity in the face of unmandated simultaneous economic change (always deeper than political change) is puzzling.
You say that,
"the collapse of the Soviet Union, the internal changes in China, the political changes in India: these are political changes which have all contributed to globalisation under my definition."
Would I be mistaken in thinking that you believe 'globalisation' almost to be like a natural state to which the ends of all affairs point? Just another economic utopianism?
Tim adds: Utopianism, no. Natural state, yes. Once you've accepted the very idea of trade, then the only thing you've got to argue about is the size of the trade area. If there were no rules about it then the natural trade area would indeed be the globe.
Posted by: Martin | Jul 30, 2007 8:51:28 AM
Gengee:
Nothing in the paragraph you quote suggests a causal relation. The final line undercuts the idea that we can invoke one of these scenarios via economic policy:
The possibility that any single emissions path will occur as described in scenarios is highly uncertain.
As I said before:
With A1 they assume average annual growth of 3% until 2100 and assert that "energy and mineral resources are abundant in this scenario family because of rapid technical progress". Does that mean these things will happen? Or that to accept the IPCC's broader conclusions we must assume they would? No. It means they adopted a set of numbers for the purposes of modelling a possible path for the climate. Nowhere do they state that, if adopted, the Worstall plan for economic growth would entail these wonders.
They have not modelled the rate of economic growth, as is implied by Tim Worstall; they have assumed it.
Posted by: StuartA | Jul 30, 2007 10:42:26 AM
Tim,
"Once you've accepted the very idea of trade, then the only thing you've got to argue about is the size of the trade area. If there were no rules about it then the natural trade area would indeed be the globe."
It is perhaps unfortunate that you choose to lump laws, nations, traditions and cultures under the rather sweeping label 'rules'.
For those things are indeed the rules by which the size of "trade areas" are set.
Tim adds: Quite. My point.
Posted by: Martin | Jul 30, 2007 7:52:19 PM
