This thesis explores the topic of decision under conditions of complete uncertainty, advocating an interdisciplinary perspective that benefits from the insights of both economists and philosophers. Thus far, most of the results in the field have been the work of economists who have been responsible for important theorems and axiomatic characterizatoins of a variety of decision rules. While proceeding from a different methodology and focus, tantalizingly similar conjectures have been made by philosophical logicians. While the work of the latter has not (yet) become as advanced in deriving important theorems, I suggest that philosophers have something useful to offer in their method of analysis that would be useful in evaluating the different solutions to standard problems in the field. I attempt to provide a new solution motivated by both disciplines.