EXCERPTS:
"So 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. It helps you know where to look for causal elements even if we cannot measure their precise contribution or how to relative weights of factors that pull in opposite directions. Economics helps us understand the relationship between the money supply and a general rise in the price level, between inflationary expectations and nominal interest rates, between expectations of the future and the willingness to invest, between policies that reduce prudence and a rise in imprudent investing. These are all things we understand better than we did 100 years ago partly because we have thought about them a lot, partly because of correlations in the data that we might view as sufficiently close to natural experiments, partly from armchair reasoning and partly from theoretical models of varying degrees of complexity.
We can’t measure any of these relationships with great precision, but we understand something and sometimes a lot about the direction that things are likely to go if something changes but nothing else does. Those are useful but modest gains in understanding. But they do not reach the level of what the media expects economists to be able to explain such as predicting the net impact of NAFTA on the US economy and the well-being of Americans, or how many jobs were created by the stimulus package of 2009. Unfortunately, economists do answer these questions with numerical precision as if they were physical scientists. My argument is that such answers are scientism and intellectually bankrupt.
Perhaps most importantly, economics can often remind us of the full range of effects of a particular policy, what Bastiat called the seen and the unseen. This is very valuable. Is it science? I don’t care. It’s a very powerful way of organizing your thinking about what happens when something changes in a complex system. Economics inevitably makes you aware of unintended or what might better be described as non-obvious consequences of a particular change.
Finally, economics is good for generating humility and preventing hubris. Remember the Hayek quote: "The curious task of economics is to illustrate to men how little they really know about what they imagine they can design."
