knew seemed to make them more susceptible to bad ideas. How can it be that reinforcing a person’s preexisting opposition to a foreign idea is worse than doing nothing? Let’s say that all your life you’d been told the story of Noah’s ark. In Sunday school you even colored an ark with crayons as you sang about animals going in two by two. But then you got to college and found your professors proposing foreign ideas about Noah’s ark. “There is no evidence of a global flood,” one might have said. “Can