It captures his frustration: arguing with someone, knowing no amount of logic or evidence will change their position.

An atheist might say its like arguing with a christian.

A pc person might say its like arguing with an apple fanboy.

Batman arguing with joker?

This was not a great or balanced blog post by any means, but I didn't think this sentence was the worst part.

Because he can't say arguing with a christian. Are you one of them?