Sustainability
We can talk all we like about recycling and sustainable agriculture, but population is the issue that really matters. Yet it is the one on which so many people are silent. We have made the human right to reproduce unchallengeable: to do so is either to be eugenicist or – as with China’s one-child policy – repressively authoritarian. But sooner or later we have to do something. No matter how much recycling we do, how much renewable energy we create and how much better we become at producing food, there has to come a time when the world’s population makes the planet unsustainable. The pressure on resources is being maintained at both ends of the spectrum: not only are more babies being born, people are living longer and longer.