Opinion: What the future looks like

It would be foolhardy to venture technological predictions for 2050. Even more so to predict social and geopolitical changes. The most important advances, the qualitative leaps, are the least predictable. Not even the best scientists predicted the impact of nuclear physics, and everyday consumer items such as the iPhone would have seemed magic back in the 1950s.

But there are some trends that we can predict with confidence. There will, barring a global catastrophe, be far more people on Earth than today. Fifty years ago the world population was below 3 billion. It has more than doubled since then, to 6.7 billion. The percentage growth rate has slowed, but it is projected to reach 9 billion by 2050. The excess will almost all be in the developing world where the young hugely outnumber the old.

If population growth were to continue beyond 2050, one can’t be other than exceedingly gloomy about the prospects. And the challenge of feeding such a rapidly growing population will be aggravated by climate change...