Proceedings of the Annual Meeting of the Cognitive Science Society

Among data implying pessimistic conclusions about human rationality, one might include evidence from the notorious Newcomb's Problem (Nozick 1969), which has hitherto, however, been largely confined to the philosophical literature. After nearly thirty years of inconclusive discussion, Newcomb's Problem is still widely seen as exposing inadequacies of the current standard theory of rational decision since the most plausible principles of choice give conflicting recommendations. Thus, Jeffrey (1983) says that Newcomb's Problem may be seen "as a rock on which...Bayesianism...must founder". Despite a staggeringly vast literature of great technical subtlety and complexity, no solution has emerged. I offer a novel analysis which goes beyond merely giving the right answer to the choice problem by also revealing the source of its persistent intractability. If my solution suggests good news about human capacity for rational choice, it entails bad news about other important problem-solving abilities central to cognitive science.