I remember having a debate on another forum with one of those "I'm smarter than everyone because" type of morons. Real inflated sense of self-worth.

A discussion on global warming basically ended up at:

Me: So you think that man is causing the earth to warm to catastrophic levels.

Him: Yes

Me: So what is your baseline? What are acceptable levels?

Him: Don't know

Me: So how do you know the actions you are taking are actually affecting anything?

Him: I don't.

That was the gist of it, no logical thinking involved, just feels. Of course, I should probably be given some blame for arguing with an idiot on the internet.