It is almost as difficult to make a man unlearn his errors as his knowledge.

A wrong belief sits in your head exactly like a right one. It has the same feel of obviousness, the same supporting memories, the same sense of being simply how things are, which is why being shown the evidence rarely dislodges it on the spot. Removing it takes the same work as learning something new, and rather more discomfort. That is why arguments so seldom change anyone in the room.

Pick one thing you are confident about and go looking for the strongest case against it, made by someone who holds it seriously. Expect the exercise to be unpleasant. Unpleasantness is what it feels like when something is actually moving.