Posers and Puzzles
23 Nov 05
If there is one person on earth who would be willing to go to hell, if therby he could ensure that everyone else on earth would go to heaven, then he will buy the amulet the last time when there are only two people not in heaven yet, and he will always sell it for a more expensive price if he acquires it before that point.
If such a person exists then then you can buy the amulet at any price, you don't need the rest of the population to be stupid.