The opposite of open-minded (DUH-uh!).
Many people are under the mistaken impression that the first
person who says "You're just being closed-minded" in a debate is automatically the winner; frequently, the first
person who says this has simply run out of facts.
Contrary to popular belief, it's also not
always bad to be closed-minded, especially towards ideas which are easily demonstrated to be false or foolish.
I'm very open-minded about
space exploration, but I'm very
closed-minded about doing a space
walk without a spacesuit.