1. Suppose, finally, that all parents tried to teach their children never to let anyone in to see their apartments if they were over 80 on the messiness scale. If such a rule of thumb were widely observed, what would be your best estimate of the messiness index of someone who said, “You can’t come in now, my place is a pit”? In a world in which everyone makes use of all available information, would you expect this rule of thumb to be stable?

What do you conclude from the fact that people really do sometimes refuse admission on the grounds that their apartments are too messy?