For someone who doesn’t care much for experimental studies and data analysis, I often come up with experimental tasks or statistical surveys for other people to do. Here is one: Take a bunch of graduate students of nuclear physics and ask them about the role of falsifiability in science. Then take a bunch of graduate students of macro-economics and ask them the same question. My guess is that the physicists will not know what you are talking about, and at any rate  wouldn’t have come accross this issue during their studies, whereas the economists will know all about Popper, logical positivism, demarcation and other latin words I never heard of.


I thought about this comparison when I watched this diavblog. As usual with bloggingheads I lost interest quickly, but it’s  worth watching for a while, if only to keep track of the fluctuations in the frequency of David Levine’s blinks while the other head is talking. Best Levine’s quote from the part I watched — `You will have to fill me on which these three axioms are’, responding to the assertion that `nothing is more true than that the three axioms of rational choice have all been falsified’. I actually replayed this part to retrieve the quote, and I still managed to forget the three axioms.

Anyway, back to my (testable !) prediction. Suppose it turns out to be correct. Then, since I am the one that made the prediction, Popper tells us that the fact that it was verified renders my explanation for it more credible. And the explanation is that physicists are robins and economists are penguins.

Let me elaborate. Richard Feyman famously said that philosophy of science is as useful to scientists as ornithology is to birds. It’s an awesome observation, and I would like to apply it specifically to the part of philosophy of science that deals with the demarcation problem, or the distinction between science and non-science. And I’ll start with the physicists, because our whole idea of science is essentially `the stuff that physicists do’. Popper was trying to pin down what are the special characteristics of the physics enterprise. Thus, the fact that physics is science is almost a tautology. Every child knows it as every child knows that robin is a bird. That’s why Popper’s (or anybody’s) answer the demarcation problem is useless to physicists.

Things are different with penguins. A layman might not recognize them as birds. In order to prove that they qualify, penguins have to appeal to some standards that describe what are the special properties of birds that distinguish them from humanities mammals. That’s why penguins care about ornithology. And that’s why economists care about falsifiability.

Rosenberg is right it’s a bit ironic that economists adopt falsifiability as a litmus test for science, since philosophers of science have generally rejected it. But the irony I think is on the philosophers, not the economists. How would the ornitologists feel if the birds that actually read their papers would only be interested in what was written eighty years ago ?