The Philosophy Department Colloquium presents
Timothy Williamson, Yale and Oxford:
“Ideally Rational Agents’ and the Nature of Desire.”
Formal decision theory is often understood as about the decisions of ‘ideally rational agents’. Presumably, such agents are not just free of computational limitations but also capable of explaining the point of their actions. One might assume that they can do so simply by articulating the decision-theoretic calculations (e.g. about maximizing expected utility) to which their actions conform. However, such explanations turn out to be self-obsessed to the point of personality disorder, and far from ideally rational. This result is independent of both the specific decision-theoretic rule in play and the specific contents of their credences and utilities. Instead, it reflects the subjectivist framework of standard decision theory. The decision-theoretic calculations come out as more rationally action-guiding when reinterpreted as a rational agent’s calculations about probabilities and values in a more objective sense. This leads to a cognitivist account of desire, whose implications for the conception of desire as belief will be explored.