funny is, i'm pretty sure the lady didn't tell them to assume the hypothetical premise that what's written on the cards is true for all cards on the table (because neither the little boy nor the girl would understand a couple of those words) this means that the girl was wrong, and the boy was right. if you hit a glass with a feather, nothing happens to it, save maybe it would add or blow off some dust or something. unless you sweep it off the table with the feather, that is...