3 POW officers were rounded up by a few guards. They were shown a box containing 5 beanies: 3 black, 2 white. They were then blindfolded and taken out into the yard. There they were lined up one behind the other, facing the same direction, so that the POW in back could see the 2 in front of him, the middle POW could see the 1 in front of him, and the POW in front couldn't see either. The guards randomly selected 3 beanies, placed 1 on each of their heads and took off the blindfolds. They were instructed that if any word came out of their mouths that wasn't the color of the beanie on their own head, they would all be shot. Any POW could answer and they were to be left in formation until they got it right. After a while out there the POW in front said with absolute confidence "I am wearing a black beanie", and he was right....how did he know what color beanie was on his head?