Sometimes I argue with a conservative (I never learn). The point of contention may be quite simple. I can have all my facts impeccably documented, and prove my argument almost mathematically, but it makes no difference: If my position is one that he identifies as "librul", my opponent will never agree. And I am convinced, it's not that he sees that he's wrong and won't admit it: he figures "it's librul, it's wrong".
A recent scientific study suggests that the liberal and conservative brains are actually quite different.
The study finds that:
conservatives tend to be more structured and persistent in their judgments...
(...which I read "closed-minded"),
whereas liberals are more open to new experiences...