Readers discuss a guest essay about birthrates and the world’s population. Also: A citizens’ celebration for America’s 250th ...

Elon Musk said the notion that humans once managed an economy will seem quaint in the future, like “cavemen throwing sticks into a fire” in retrospect. The remarks came during a demonstration of his ...

What if the challenge for humanity’s future is not too many people on a crowded planet, but too few people to sustain the ...

But as much as AI’s potential can cause harm, blaming it alone misses the point and likely makes these problems worse. Humans ...