This, to me, is one of the most interesting things about dissonance: It's to the extent that a belief is really deeply important to us—that's when we become most tenacious in holding on to it. It's why, for example, it's not just dumb people who feel the need to reduce dissonance; the greatest danger comes from smart people who refuse to accept the evidence that they have done something foolish or stupid or that they were holding on to a belief or a medical practice long past its shelf life.