Having recently bashed Paul Krugman, and in the full expectation that I’ll have occasion to bash him again, let me interject that Krugman is not just a first rate economist; he is also, when he wants to be, a superb economic communicator, with a long paper trail to prove it.
Take, for example his essay on the widespread failure of intellectuals to grasp Ricardo‘s theory of comparative advantage (the basis of the case for free trade). Instead of simply bemoaning the problem like the rest of us, Krugman makes a valiant and useful attempt to identify its root causes.
He starts with an analogy I’m also fond of (I’m not sure which of us has been using it longer): The theory of comparative advantage is like the theory of evolution by natural selection—to those who understand it, it is simple and compelling; yet non-experts can find it remarkably difficult to grasp.
In The Big Questions, I argue that this analogy ultimately breaks down: The theory of evolution is compelling largely because of the evidence that supports it, while Ricardo’s theory is compelling largely because of the logic that supports it. It’s not too surprising that a first-rate physicst or literary critic could be unfamiliar with a body of evidence, but it’s a little more unsettling when that same physicist or literary critic can’t follow a simple chain of logic.
Krugman points out, though, that the chain of logic might be less simple than economists realize, resting as it does on several other points that we’ve learned to take for granted, and he makes a useful stab at enumerating these points and pondering how we can communicate them better. He observes also that while economists understand the importance of reasoning from models, they often fail to realize that not everybody thinks this way. Would-be communicators, take heed.
Sometimes I wish Krugman would take better heed himself. My main problem with so many of his New York Times columns lately is that they don’t seem to proceed from anything I can recognize as model-based reasoning. (Well, that plus what looks to me like a pigheaded obtuseness about the perils of centralized power.) But when he was good, he was very very good. Don’t believe me? Check out his web archive. Start here, say, or here or here. There’s stuff there I disagree with (especially some of the macro stuff) but mostly there’s excellence, and more than enough to make the world a smarter and a richer place.
