By definition, we believe that each of our beliefs is true. And yet, simultaneously, we must admit that some of our beliefs must be wrong. We can't possibly have gotten absolutely everything right. This becomes especially obvious when we consider the huge number of beliefs we have, the complexity of the world we live in, and the number of people who disagree with us. The trouble though is that we don't know which of our many beliefs are wrong. If we knew that, we should have stopped believing th...