Abstract
Utilitarian (U.) theories must be capable of being applied in practical reasoning, or they would have no value as a guide to rational conduct. However, I show that epistemic extensions to U. theories produce logical confusion. Basic questions about what one needs to know in order to apply a U. analysis embroil one in an infinite regress. And attempts to incrementally apply U. either are no help at all (leaving one entirely 'in the dark'), or in general constitute arbitrary gambles which no practical reasoner could defend taking. These problems are serious enough to completely discredit U. theories as having any relevance to practical reasoning.