Abstract
How should I update my credences when I get de se evidence? And how should I reason when the world might contain more than one individual with all the experiences and apparent memories I have right now? A principled answer to these questions would help us solve several puzzles in confirmation theory, such as Sleeping Beauty, Doomsday, and the question whether finding out that the universe is ‘fine-tuned’ would count as evidence for the existence of many universes. This paper looks at three ways to answer these questions. Each can be thought of as replacing the standard conditioning rule with a new normative principle that constrains credences given evidence (whether de dicto or de se).