Refining vague degrees of confidence for decision making

Bayesian principles of indifference imply strict commitment to states of neutrality among alternate possibilities. This strong psychological state does violence to representing complete uncertainty about a proposition, where judgments seem quite vague instead of sharply split. Put in this way, Adam Elga???s principle of indifference for self-locating beliefs is symptomatic of his further commitment to the requirement that perfect rationality requires sharp credences because norms for action require sharp credence. His arguments for this latter commitment suggest that no theory that permits vague probability can provide norms to account for rational action. In the first half of this paper, I first expose that such indifference principles must be constrained by practical interest to do the work Elga proposes. In the next half, I argue for a norm that the vague probability theorist can use to account for rational action