Given this, it is likely that world population will peak at nine billion in the 2050’s, a half-century sooner than generally anticipated, followed by a sharp decline. One could argue that this is a good thing, in view of the planet’s limited carrying capacity.
如此看来，世界人口将在21世纪50年代达到90亿的顶峰，比普遍的预测早半个世纪，此后将大幅下降。你可以认为这是件好事，因为地球的承载力是有限的。但是，当人口学动态逆转时，世界将面临一组不同的问题。