Everettian Illusion of Probability and its Implications for Doomsday and Sleeping Beauty
Examensarbete för masterexamen
An attempt at a satisfying compromise for the resolution to the Sleeping Beauty problem is presented. It is satisfying in virtue of explaining why the solution has eluded us for so long. The proposed reason for that the solution has eluded us is that the correct analysis of the Sleeping Beauty problem hinges on the consequences of the Many-Worlds interpretation of quantum mechanics being correct, consequences that have not been considered in the literature on the Sleeping Beauty problem. The premise that the Many-Worlds interpretation is correct makes the argument speculative. If the speculation is correct though, this account avoids problems of automatic confirmation of hypotheses postulating a greater number of observers (e.g., the Presumptuous Philosopher problem) and avoids problems of credence about future chance events differing from objective chance (e.g., if the coin is tossed on Monday evening in the Sleeping Beauty problem), two problems that usually can’t both be avoided. The cost of accepting this account is that a distinction is made between credence in events with objective chance and credence from ignorance about deterministic facts. Beauty is a Thirder if both possibilities that she is uncertain between correspond to actually existent world-branches (i.e., resulting from a chance event) and a Halfer if they don’t (i.e., ignorance about which possibility is actually existent). This distinction was proposed in this context by Wilson (2014) and is criticized in Bradley (2015). This account challenges the criticism by justifying the distinction from considerations about the physical nature of reality.
Bayesian reasoning, Decision-theoretic rationality, Sleeping Beauty problem, Doomsday Argument, Everett, Many-Worlds interpretation