A joke from my grandfather Billy walks into the office one day looking very excited. He rounds up all the other guys in the office and says ""I found the greatest horse in the world, and if we all bet on him in the next race, we could all be rich."" ""What makes you think this horse is so great?"" asks a skeptical co-worker. ""Well,"" says Billy, ""this horse has never been ridden."" ""This is ridiculous,"" says the co-worker, ""if this horse has never even been ridden, how can you be so sure it…