Paul Romer: Freshwater Feedback on Mathiness

More from Paul Romer:

Freshwater Feedback Part 1: “Everybody does it”: You can boil my claim about mathiness down to two assertions:

1. Economist N did X.
2. X is wrong because it undermines the scientific method.

#1 is a positive assertion, a statement about “what is …”#2 is a normative assertion, a statement about “what ought …” As you would expect from an economist, the normative assertion in #2 is based on what I thought would be a shared premise: that the scientific method is a better way to determine what is true about economic activity than any alternative method, and that knowing what is true is valuable.

In conversations with economists who are sympathetic to the freshwater economists I singled out for criticism in my AEA paper on mathiness, it has become clear that freshwater economists do not share this premise. What I did not anticipate was their assertion that economists do not follow the scientific method, so it is not realistic or relevant to make normative statements of the form “we ought to behave like scientists.”

In a series of three posts that summarize what I have learned since publishing that paper, I will try to stick to positive assertions, that is assertions about the facts, concerning this difference between the premises that freshwater economists take for granted and the premises that I and other economists take for granted.

In my conversations, the freshwater sympathizers generally have not disagreed with my characterization of the facts in assertion #1–that specific freshwater economists did X. In their response, two themes recur:

a) Yes, but everybody does X; that is how the adversarial method works.
b) By selectively expressing disapproval of this behavior by the freshwater economists that you name, you, Paul, are doing something wrong because you are helping “those guys.”

In the rest of this post, I’ll address response a). In a subsequent post, I’ll address response b). Then in a third post, I’ll observe that in my AEA paper, I also criticized a paper by Piketty and Zucman, who are not freshwater economists. The response I heard back from them was very different from the response from the freshwater economists. In short, Piketty and Zucman disagreed with my statement that they did X, but they did not dispute my assertion that X would be wrong because it would be a violation of the scientific method.

Together, the evidence I summarize in these three posts suggests that freshwater economists differ sharply from other economists. This evidence strengthens my belief that the fundamental divide here is between the norms of political discourse and the norms of scientific discourse. Lawyers and politicians both engage in a version of the adversarial method, but they differ in another crucial way. In the suggestive terminology introduced by Jon Haidt in his book The Righteous Mind, lawyers are selfish, but politicians are groupish. What is distinctive about the freshwater economists is that their groupishness depends on a narrow definition of group that sharply separates them from all other economists. One unfortunate result of this narrow groupishness may be that the freshwater economists do not know the facts about how most economists actually behave. ...[continue]...