"Absolutely nothing!" I said. "You're still the same person you were, and everything goes on like normal."
And that's one way to tell that God's not real. If you stop believing in cars and decide to walk out in the road, reality will soon disconfirm your belief. If you disbelieve in food and water and stop eating and drinking, you die. But if you stop believing in supernatural beings... it's amazing how irrelevant your past belief can seem, so quickly.
It's like Philip K. Dick said:
"Reality is that which, when you stop believing in it, doesn't go away."Youngest Boy thought about all this and said, "But you could not believe in atoms, and nothing would change." He's very smart. You have to watch yourself with this kid.
"That's true," I said, "With atoms, it would take a long time to notice you were wrong. You probably wouldn't know until you tried to do some research involving atoms. Then you'd realise that people who know about atoms could predict things you couldn't."
But what does belief in god help you predict? You can't work out who will be cured of illness when you pray. Most people get better with most diseases, some don't, and some die. Then you say, well, that was god's plan. It lends itself to loads of ex post facto rationalisation, but not prediction.
It's not all true that nothing changes though. You are finally able to embrace reason without having to fear it. Because, post-deconversion, reason has already knocked down your rickety system. There's no more harm it can do you. You are free.