What if there is no human-caused global warming?

A long time ago, someone wrote to me and asked me what I would do if I was wrong about climate change? I answered him like this.

Just the other day someone else wrote to me. He went on about liberals and how they complain and a bunch of other things he doesn't like about them. Then he said:

"But you're right about one thing. We need to take care of our planet. I don't even know if I believe in global warming. But the thing is, if it doesn't exist, it's even more important that we take care of t...