Rational Crank

My friend who is participating in the dowsing test emailed me. Here is part of the email: Please bear in mind that we are testing a specific and limited form of dowsing - I have never made any claims regarding dowsing for water, underground cavities, or anything other than ferrous metals - in fact, I am very skeptical about these other types of dowsing. We could also test the subterranean flowing water type of dowsing in another experiment, but it would require a different, and more complicated, test setup. I'd also like to build a dowsing machine to totally remove human subjectivity from the process, but this too is for later. Do you have a date or place in mind? We need to make this into a fun interesting event! My response: You are correct. First priority is that the test must be fun. I propose that all the guests at the party state which result they think will prevail, Skepticism or Dowsing. They are each given something to identify their position (preferably a silly hat). Each...