Have your eyes ever played tricks on you? Have you ever seen a mirage? Have you or anyone you know ever been asked to serve as a witness in a criminal trial? If you answered yes to any of these questions, then you know what it is like to doubt what you've seen. Have you ever felt like you "heard" things others did not? Have you "known" things without knowing? Have you puzzled at the ability to discern what is going on in the hearts and minds...