FR Columnists' Corner Heads I Win, Tails You LoseBy William McKinley Imagine if people cared about coin flips. I mean, cared deeply and passionately about if heads would come up or if tails would come up. Imagine there being heads partisans, and tails partisans, and imagine there being moderates who can prefer heads one time and tails the next, depending on the coin, or the day, or the way the wind blows. And imagine that our fictitious little land does not know that an everyday coin will come up heads half the time, and tails half the time. Now imagine...