Newcomb’s Problem

Abstract

The first three paradoxes revolved around questions of what would be factually true, given certain assumptions. The rest concern questions of what someone called the player should do given certain situations, thereby entering the realm of decision theory. To guard the claim that these paradoxes depend on probability concepts, the possible meanings of “should” must be severely curtailed. This can be accomplished by stipulating a few intuitively obvious rules such as that given a choice between two options, the player should take the one of greater value, and also by stipulating the values assigned to relevant elements in the problem.