"We plan to put Beauty to sleep by chemical means, and then we’ll flip a fair coin. If the coin lands Heads, we will awaken Beauty on Monday afternoon and interview her. If it lands Tails, we will awaken her Monday afternoon, interview her, put her back to sleep, and then awaken her again on Tuesday afternoon and interview her again. The (each?) interview is to consist of the one question : what is your credence now for the proposition that our coin landed Heads? When awakened (and during the interview) Beauty will not be able to tell which day it is, nor will she remember whether she has been awakened before. She knows about the above details of our experiment. What credence should she state in answer to our question?"
In light of the recent thread on the Monty Hall problem
, here's a probability puzzle that's even more mind-bending: the Sleeping Beauty problem
. Some people say the answer is 1/2
. Some people say the answer is 1/3
. Some people say there is no answer
. Papers have been written
which can't resolve this one.
posted by salmacis
on Jul 21, 2004 -