The nation’s falling fertility rate underlies many of our most difficult problems. Once a country’s fertility rate falls consistently below replacement, its age profile begins to shift. You get more old people than young people. And eventually, as the bloated cohort of old people dies off, population begins to contract. This dual problem—a population that is disproportionately old and shrinking overall—has enormous economic, political and cultural consequences.
For two generations we’ve been lectured about the dangers of overpopulation. But the conventional wisdom on this issue is wrong, twice. First, global population growth is slowing to a halt and will begin to shrink within 60 years. Second, as the work of economists Esther Boserups and Julian Simon demonstrated, growing populations lead to increased innovation and conservation.