Suppose you have a machine that can switch two people's souls with each other's bodies, but can only do it once between any pair. What is the minimum number of people you'd need to return people back to their bodies?
As well, question. Is there a set of numbers that you could put on two 6 sided dice in such a way that you would get the same probabilities of a normal pair of 6 sided dice? If so, what are they? Are they the only variant?