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ost_uid0]Q. What breed of dog does Janeway wish Molly (her pet, not the O'Briens' daughter) were?
A. Microsoft.
The Pop Quiz Paradox is as follows:
A professor of philosophy tells his students that he will give them a pop quiz next week, and it will occur on a day when they are not expecting it (though I first saw this in the form of a judge telling a convict that he will receive the death penalty next week, and that it will occur on a surprising day). One of the students immediately draws the obvious conclusion that the quiz will not be given on a Friday. If it were, the class would know when Thursday had passed without any pop quiz that the quiz would have to be on Friday in order to get it in before the week ended. Therefore, they would hardly be surprised when on Friday the professor passed out the quizzes. However, she continues this line of thought. Given that she knows that the quiz cannot be given on Friday, what can she conclude? If Monday, Tuesday, and Wednesday pass without any pop quiz, then she will know that the professor must give the quiz on Thursday or face an unsurprised class the next day. With this knowledge, and given that the quiz would not have been administered through Wednesday, the students will come to class Thursday certain that the professor must give the quiz that day if he is to avoid unsurprise on Friday. That leaves Wednesday as the latest that the professor can give the quiz. But she can eliminate Wednesday as a possibility by a similar thought process, then eliminate Tuesday and then Monday also. Thus, the professor cannot give a surprise quiz at all the next week. Satisfied with this conclusion, which does not require her to study, the student conveys her conclusions to her friends. Next week, the entire class is confident that they are safe from surprise quizzes.
But on Tuesday, the professor gives them a pop quiz anyway! The whole class is surprised, because they thought they were safe from any such thing. And so the professor's statement that the class would be surprised on the day of the quiz is proven true. :smile:
Let's see how many headaches *that* induces...
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