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Look after future generations vs Realise human potential

Fears that we are too many are nothing new. As long ago as 1798, the English writer Thomas Malthus warned that a growing population would eat its way through the planet’s finite resources, condemning millions to die of starvation.

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We haven’t exhausted our supplies quite yet, but seven billion people later our planet’s ability to support us all comfortably does appear to be under threat. If we all lived like affluent Americans, say, resource consumption and carbon emissions would be at unsustainable levels. Given the clear and present dangers posed by climate change, how can we look after future generations without keeping half of the world’s population in poverty?

For Travis Rieder, a bioethicist at Johns Hopkins University in Baltimore, the answer is reducing birth rates – and not in the places you might expect. When it comes to climate change, says Rieder, “my American kid is way more problematic than the many children a family might have in poor, high-birth-rate countries”. And should the worst consequences of climate change come to pass, it will be the poorest that suffer most severely. So let’s assume that the West is incapable of slashing carbon emissions or finding a technological silver bullet (see “The ethics issue: Should we geoengineer the planet?“). In this case, we are obliged to explore all options, including the taboo subject of population control. …