I’ve always liked Churchill’s definition of a fanatic. “A fanatic is one who can’t change his mind and won’t change the subject.” Once you get past the witty aspect of the definition, there’s a deep truth in it too. They simply can’t change their mind.

I’ve seen a lot of debates in the blogosphere, where earnest attempts to show a fanatic not just a line of reasoning but the publicly documented facts about something, have failed utterly. They were never going to listen or be persuaded; they can’t change their minds. It’s as simple as that. Rational dialogue with them aimed at somehow converting them to your viewpoint is a losing strategy because it’s a waste of your time and does absolutely nothing to stop them anyway

There is also an insidious danger to this sort of interaction with them; you start to get imprinted by them. If you’re not…