… the fact that economists did not foresee the Great Recession with any precision and have failed to model accurately the recovery does not mean that economics or even macroeconomics is worthless. My claim is simply that we should recognize the limits of reason in analyzing complex systems with millions of decision-makers, numerous feedback loops, institutional features (synthetic CDOs, the repo market, the willingness of the Fed to bail out bondholders) that are difficult to model in tandem with the outcomes we care about. Finally, there are important variables that we cannot observe directly such as expectations, anxiety, confidence, overconfidence and so on.
So what is economics good for? It’s good for organizing your thinking.