And what about society? What will happen to the world over the next twenty, fifty, or a hundred years if scientists and doctors create a way to keep a severed head alive for months or even years? Will the operation be done to good and humane people who want to help society? Or would it be done to ruthless dictators like Hitler and Stalin?

I don't know the answers, but those questions won't go away. And they're not just coming at me. They're coming at everybody, like a high-speed train roaring through the night.