 It's when you, for no reason other than the fact that it is what most people believe, you reject it. And then you go find some other theory that has no evidence for it. And you passionately defend that instead. I mean, that is when it becomes irrational. And that seems to be what's happened with, for instance, the moon landing stuff. But the point is that they're starting from a rational place. It's skepticism. And they're ending every once in a while.