Post hoc ergo propter hoc Krugman is not offering up a hypothesis that is better at explaining observations than his opponents. He is making an argument based

Post hoc ergo propter hoc Krugman is not offering up a hypothesis that is better at explaining observations than his opponents. He is making an argument based on an ideological position while ignoring evidence suggesting, at a minimum, that his hypothesis is not supported. This is not science. As Cochrane notes in one of his "minute points", *Pretty much all we have been doing for 30 years is introducing flaws, frictions, and new behaviors, especially new models of attitudes to risk, and comparing the resulting models, qualitatively to data." This set of "we" includes the behaviorists and "complexity economists" (i.e. people who really enjoy massive simulations of simple agents).