The Evil Pleasure
Robin Hanson on what he terms the evil pleasure:
We feel a deep pleasure from realizing that we believe something in common with our friends, and different from most people. We feel an even deeper pleasure letting everyone know of this fact. This feeling is EVIL. Learn to see it in yourself, and then learn to be horrified by how thoroughly it can poison your mind. Yes evidence may at times force you to disagree with a majority, and your friends may have correlated exposure to that evidence, but take no pleasure when you and your associates disagree with others; that is the road to rationality ruin.
He was spurred to this thought by an article by Pascal Boyer in Nature, unfortunately barricaded behind a pay wall. However, you can search for Pascal Boyer articles in Google Scholar. Many are available there for the reading if you click on the "All # versions" link at the bottom of each listing.
Hanson's blog is titled Overcoming Bias, and he's ruthless in that goal. I find his advice stern yet inspiring.