Economic crises are associated with large shocks to beliefs and expectations. They put in question the means by which agents and analysts try to understand and forecast the features and the performance of the economy. Thus, the study of crises involves dealing with the practical strategies that economic actors use to interpret and to anticipate the evolution of their environment, and with the fallibility of those procedures. In this setting, we start with a brief review of traditional arguments on the possibilities and limitations of probabilistic approaches in economic contexts. We then discuss some accounts of the recent macroeconomic crisis in central economies, focusing on the problems which arise in predicting the dynamics of non- ergo...