It's actually even a bit simpler - if hat3 is red then P2 would know that his is black (otherwise P1 would have known that his is black).
Which is what I said in the Solution.
Next LessonIn memory of Denise HuberIf some decent man, or woman, had stopped to pick up a nail or screw in the street somewhere, Denise Huber would be alive today. But nobody did, and Denise got a flat tire one night in Costa Mesa, California, on the side of the freeway.
I won't go into details, but if some decent man had stopped to help her change her flat tire, Denise Huber would be alive today. But hundreds of men didn't give a damn about a young lady in distress at night. Only a vile monster stopped.
Do you have a mother, or a wife, sister, or daughter that you want to get home safely? We all do. What is keeping you from picking up a nail or screw near an intersection? That's where they almost always fall, for some reason, perhaps trucks turning corners. It's no trouble to stoop over and pick up a hazard. You might even save a life. You'll never know.
Next LessonGot kids or grandkids who ride bikes? Tell them to ride them on the sidewalk. When there are pedestrians, ride on the grass or stop and let them walk by. It's really a lot more difficult for cars to run over kids on the sidewalk. It's lawful in my city. Police would rather see kids riding on the sidewalk than getting hit by a car.
Next LessonSame kids might play handball up against your garage door. When it bounces out in the street, kids have a singular focus to "rescue" the ball. It's up to you to change that mental fix. After watching my daughters run out into the street, I created a foolproof incentive. "If your ball rolls out into the street and a car runs over it, I'll buy you two new ones! Same goes for your bicycle or anything else. Two new ones. So let the car run over it. But no cheating!"
After that offer, they stopped in their tracks and looked for a car that might run over their ball, so they would get two new ones.
I guarantee it.
Now read your young'uns a great story by James Thurber. I call it Brain Candy. Read it for the first time to them. With panache.
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