Among economists, discussion of problems involving uncertainty is po­larised between advocates of formal decision theories, who claim that un­certainty can be tamed by careful consideration of information and elicita­tion of preferences, and critics who argue that uncertainty is fundamentally irreducible. Improvements and generalisations of formal decision theory, responding to critical arguments, have generated new counterexamples and anomalies, and new evidence about the limits of our capacity to deal with uncertainty. So, although our understanding of the issues has deepened, the fundamental debate is unresolved.