The lament at overpopulation is a mask for misanthropy. It is sustainable if the rich world consumes less.

On one day — one minute — in the next month, the world's seven billionth human resident will be born. The United Nations is marking the occasion on the last day of October with what it describes it as an “opportunity” to promote “seven billion actions” for environmental sustainability and women's education, estimating that the world's population will top out at nine or 10 billion mid-century before declining as economic development matures in countries with higher birth rates.

They appear to be right. Worldwide, fertility rates in countries such as Mexico and Bangladesh have fallen vastly in a single generation — thanks, in large part, to what economist Amartya Sen terms “development as freedom”. Yet Thomas Malthus, who at the turn of the 19th century predicted that population growth would inevitably lead to famine, still has his fans among those inclined to believe that humans mean little but bad news.

In Britain Population Matters, the Green party and the naturalist David Attenborough are united in agreeing that the U.K. population is too big and needs to be “encouraged” to bring about the conditions for its managed decline. Rather than place their focus on the waste and overconsumption endemic to rich nations such as ours, their solution to environmental pressure is to make sure there are fewer of us around in the future to mess things up.

The Greens have had a discrete population policy for more than 20 years and encourage the promotion of “informed debate on a sustainable population for the U.K.”, coyly refraining from suggesting its own preferred figure. That's not to say the party's leaders haven't in the past: two years ago its former leader, Jonathon Porritt, described our over-fecundity as “the ghost at the table”.

For its part, Population Matters reveals the moral crusade beneath its rational concern in a summary of its U.K. policy. First, it advocates reducing the rate of immigration so that it matches the rate of emigration — leaving us with a reduced population of ageing people. Second, it plans to “reduce the number of teenage pregnancies”: an interesting target for attention, considering the age of the average first-time mother is now very close to 30. Third, it proposes that families “stop at two” children, which is what the overwhelming majority of households do already.

At 62.3 million, Britain's population in 2010 was about 10 million short of mid-1960s estimates for the year 2000. Back in 1965, the Central Statistical Office projected that 1,527,000 live births would take place in the first year of the new millennium, based entirely on trends at the time. The actual figure, when that year came around, was 604,441, suggesting that greater equality and opportunities for women had led them to “stop at two” without having to be told to.

Around the world, policies to promote family planning only work when people of child-bearing age are able to factor in the prospect of stability and choice in other areas of their lives. We have found ways of making it possible to sustain ourselves at a time when the world population has increased exponentially. What prevents the world being fed equitably and healthily is the fact that rich-world governments can't bear the thought of doing two unpopular things.

First, they won't encourage individuals to reduce their own consumption; and second, they won't facilitate moving that consumption away from petrol, meat, imported fruit and other adoptive “necessities” of the world middle class. Stuffed and Starved, the incisive 2008 book by Raj Patel, shows the symbiosis between obesity in rich nations and undernourishment in poor ones, caused by the hogging of food markets by those best placed to profit from them.

Even Population Matters admits that “managing population decline is like trying to hit a moving target”. The question is, then, why even try? Nevertheless, let's assume that the world's population could be engineered to decline significantly from seven billion. For there to be any significant impact on the environment, that decline would have to take place in countries that already consume a far more than sustainable share of the world's resources.

Looked at from any angle, advocates of population control put across subjective moral arguments that masquerade as practical concerns. We now have the grotesque spectacle of the government of Australia, a continent-sized country with a minuscule population, simultaneously inviting people from other rich countries to live and work there while producing YouTube videos intended to deter people from poor countries from trying to enter.

To paint humans in their struggle for healthier, more prosperous, lives as somehow grabbing and greedy is as miserly and unimaginative as it gets. So let's see this apparent rationalism about population for what it is: fear and misanthropy wearing a mask of concern. — © Guardian Newspapers Limited, 2011

(Lynsey Hanley is the author of Estates.)

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