Original URL: https://www.theregister.com/2008/02/20/optimum_population_report/

Die for Gaia, save the planet?

The Soylent wing of the Green movement examined

By Tim Worstall

Posted in Science, 20th February 2008 13:00 GMT

The enviroloonies seem to have found their way out of the asylum again: this time to tell us that 70 per cent of Britons should die for the sake of Gaia. That's not quite the way they put it, of course. Rather, the Optimum Population Trust (there's a pedantic part of me that wants to tell them it's Optimal) tells us that the maximum sustainable population of the UK is 17 million: given that there are north of 60 million currently, we can only avert the coming End Times if the extra pop their clogs soonest.

It's not bad for a paper on demography, economics, the environment and their interactions written by a physicist, that is, a paper written by someone with no knowledge of any of the three basic disciplines. The argument rests on two fundamental pieces of illogic.

The first is the use of the Commoner-Ehrlich equation which is that ecological Impact is equal to Population times Affluence times Technology or:

I = P x A x T

Paul Ehrlich, you might recall, is the man who in the 60s predicted hundreds of millions starving in India in the 70s and the US in the 80s. Then in the 70s predicted the same in the 80s and 90s and, in his latest book, Real Soon Now. The flaw in this equation is that technology is held to multiply the impact instead of, as is obvious to even the casual observer, divide it.

If you haven't spotted why yet, consider this. Are we using higher technology than hunter gatherers? Yes? Good, now, if there were 6 billion hunter gatherers around, would Gaia simply be, as at present, a bit grumpy, or even worse off? Correct, there wouldn't be any biosphere at all as that many humans with flints and spears alone would have eaten every thing on the planet and then each other. As, indeed, hunter gatherers did with the megafauna of every place they got to outside Africa, the Aborigines, the Clovis culture in North America, the Maori in New Zealand and so on. The equation should thus read:

I = (P x A)/T

For higher technology reduces the environmental impact. The effect of this upon the logic used in the paper is this. As the paper says, higher technology and increased affluence increase the pressure on the environment, and as none of us is prepared to give up the levels of both which we already have, the only thing we can do to save the planet is to have fewer people. But getting the equation the right way around removes this constraint: we can reduce the impact by having better technology and there's no need to go round slaughtering the chavs (well, OK, not this reason then). And most importantly, as we'll see, we can do this by creating technology which has lower carbon emissions.

The Footprint industry

The second conceptual error is that in their calculation of the permissible population level they use the concept of ecological footprints as calculated by Mathis Wackernagel. Now in one way I've got a lot of time for him: it's not everyone who manages to turn their Ph.D thesis into a thriving international business, so hats off, well done sir. On the other hand, that thesis is what is technically known in serious circles as horse manure. For example, when looking at the carbon emissions of nuclear power, the calculation is:

Nuclear power, about 4 per cent of global energy use, does not generate CO2. Its footprint is calculated as the area required to absorb the CO2 emitted by using the equivalent amount of energy from fossil fuels.

Mat bubba: over the cycle nuclear does have CO2 emissions, roughly the same as hydro or wind, less than half solar and a tiny fraction of coal. But our ecological footprint idea gets much worse than that. The essential idea is that we work out how much land a particular activity requires. Then we work out how many activites and how much of such there are and then look at how many hectares of land we need to be able to do all of them. This is what gives us our regular yearly (when Mathis and his boys release their annual update) cycle of we need "three more earths" if we're all going to carry on living like this.

Again there's a conceptual error about technology: thinking that the amount of land we need to do something is static, which it plainly isn't. We get more food off a hectare now than we did last year, as we have every year for at least a century (yields have been going up one per cent a year for at least that long) and so on. But wait, there's yet more.

Each piece of land is only allowed to count once. The land needed to recycle CO2 emissions is somehow different land from that needed to grow the food: that plants eat CO2 to turn it into my food gets missed.

Even given all of this exaggeration the actual end finding of the ecological footprints calculations is that we've got plenty of land to do everything except recycle our CO2 emissions, something which really isn't all that much of a surprise. We've had thousands of scientists labouring away for more than a decade to tell us that, they even wrote a great big report about it. And guess what the result of that report is? If we can invent a few more bright shiny new technologies that don't emit carbon then everything is just hunky dory.

Death cult

In the end this report is just another sad set of scribblings from people who would appear to have some deeper personal problems. Perhaps it's the thought of people having sex without a full body condom that does it, or perhaps they've come over all Fran Liebowitz ("Children don't smoke enough and I find that they're sticky, perhaps as a result of not smoking enough") but something is clearly wrong, when we read:

"It follows that if it is not possible to constrain affluence and technology, then the only parameter left to constrain and reduce is population."

Their sad misunderstanding about the effects of technology blinds them to the truth, that by not constraining technology we don't have to constrain either affluence or population. The late great Julian Simon once calculated that we had the resources for a permanently growing economy and population for the next 7 billion years. That might be a little Panglossian, to be honest, but it's more accurate than the insistence that there should be fewer, poorer people. ®

Tim Worstall knows more about rare metals than most might think wise, and writes for himself at timworstall.com, and for The Business, among others. He is a Fellow of the Adam Smith Institute.