When I was about six, my dad took me to see an old dentist who worked in the Williamsburgh Savings Bank. Once I was in the chair, the dentist pointed up at the ceiling, to a discolored spot that had probably been left by a water leak. "You see that spot? Your friend Adam was in here last week-- and that's where he hit the ceiling." Adam was the kind of kid who would hit the ceiling if someone tried to drill his teeth, and at that age, I had no sense of sarcasm, so I took him seriously. Obviously, after that it was a pretty unpleasant visit, and I never went back.