A probability fallacy. At a time when plane hijackers used the threat that they would explode a bomb in their luggage if the pilot did not do as they asked, it was suggested that one should pack a bomb in one’s own luggage, since the probability of there being two bombs on the same aircraft was minimal. The logic fails, since the event of interest is not whether there is a bomb on the plane, but whether one of the other passengers has packed a bomb.