James Kwak at the Baselinescenario has been writing about economism often lately. I suppose he does have a new book coming out so that he has a pecuniary incentive to draw attention (To invoke economic theory! Ha).
I have been posting a lot about evils of economism, wonkism, and scientism. I am hardly a supporter of the tendency towards economism, but I find the currently fashionable attacks on economism troubling. A bit of background: although I wound up in political science academia via history and economics, I had begun in physics and math (I wound up in social sciences because I wanted to study history like a mathematical physicist–which, in retrospect, seems to have been a very bad idea), and I had experience teaching physics to high school students at a fairly advanced level, of which I am quite proud.
My modus operandus when teaching physics was always geared to show the limits and pitfalls of theories that were “abstractly” right: e.g. the laws of motion. The typical demonstration would involve calculating some properties of moving objects on different surfaces using the textbook formulas followed by experiments that show how they pan out. For example, do objects with equal mass that are subject to the same force accelerate at the same rate? The short answer, of course, will be no: smoother surfaces lead to greater acceleration, but, at no time, does the observed acceleration match that predicted by the formulas. The consequence of this was twofold: 1) the formulas are of limited value when in real life because there are other forces at work not accounted for in the “theories”; 2) these other forces vary depending on the smoothness of the surfaces, among other things. Of course, these “other forces at work” reside in the residuals from the prediction from the theory: in other words, you use the theory to establish a baseline, and you theorize about these other forces based on the patterns of deviations from the theory’s prediction. In other words, the theory is valuable because it is quite wrong, even if “fundamentally right.”
The take-home point from these exercises is not so much that the laws of motion are wrong because they cannot describe the actual observations perfectly. Indeed, you SHOULD accept the laws of motion as if they are true, as the baseline from which you begin your inquiry. The real point is that the actual motions are more complicated and there are other potential discoveries to be made because the existing theories are incomplete, as reflected in the mismatch between the theory and the data. The consequence of this is that, by going through these demonstrations, the students learned something about friction.
Feynman, of course, made this general point often, as exemplar of what he considered good science. Consider the following passage from his famous address about “Cargo Cult science.”
For example, there have been many experiments running rats through all kinds of mazes, and so on—with little clear result. But in 1937 a man named Young did a very interesting one. He had a long corridor with doors all along one side where the rats came in, and doors along the other side where the food was. He wanted to see if he could train the rats to go in at the third door down from wherever he started them off. No. The rats went immediately to the door where the food had been the time before.
The question was, how did the rats know, because the corridor was so beautifully built and so uniform, that this was the same door as before? Obviously there was something about the door that was different from the other doors. So he painted the doors very carefully, arranging the textures on the faces of the doors exactly the same. Still the rats could tell. Then he thought maybe the rats were smelling the food, so he used chemicals to change the smell after each run. Still the rats could tell. Then he realized the rats might be able to tell by seeing the lights and the arrangement in the laboratory like any commonsense person. So he covered the corridor, and, still the rats could tell.
He finally found that they could tell by the way the floor sounded when they ran over it. And he could only fix that by putting his corridor in sand. So he covered one after another of all possible clues and finally was able to fool the rats so that they had to learn to go in the third door. If he relaxed any of his conditions, the rats could tell.
Now, from a scientific standpoint, that is an A‑Number‑l experiment. That is the experiment that makes rat‑running experiments sensible, because it uncovers the clues that the rat is really using—not what you think it’s using. And that is the experiment that tells exactly what conditions you have to use in order to be careful and control everything in an experiment with rat‑running.
I looked into the subsequent history of this research. The subsequent experiment, and the one after that, never referred to Mr. Young. They never used any of his criteria of putting the corridor on sand, or being very careful. They just went right on running rats in the same old way, and paid no attention to the great discoveries of Mr. Young, and his papers are not referred to, because he didn’t discover anything about the rats. In fact, he discovered all the things you have to do to discover something about rats. But not paying attention to experiments like that is a characteristic of Cargo Cult Science.
The part about how Mr. Young did not discover anything about the rats always stuck at me. Of course, Mr. Young discovered things about rats, just that he discovered nothing “fundamental” about rats. Something that I hadn’t realized, until years later, was that I was guilty of the same sin as Mr. Young, so to speak, in my friction and motion demonstrations: of course, they showed rougher surfaces lead to lower acceleration, like funny noises leading to rats finding their way around the maze. They do say something about actual motion and rats–the data says so. But I did not say anything fundamental about motion: a = f/m is still the basic law of motion. I simply made a slight modification: a = f/m – f(smoothness), i.e. just an “error” term that happens to be biased (i.e with a mean not equal to zero.) Mr. Young did not say something about how rats find their way in the maze, but, in a sense, he discovered something even more fundamental about rats than their maze-exploration skills–rats have a very good sense of hearing and making use of it in their lives.
The trouble with the counterarguments against economism is that they are as laced with political motives as economism, and, as such, as as guilty of cargo cult tendencies. So if the rising minimum wage does not lead to higher unemployment empirically, there is no dispute that this raises significant questions about the theoretical proposition, but this is not necessarily a “proof” that unconvincingly shows that minimum wage has nothing to do with employment. A good experimental scientist will want to know whether some conditions can be found where an increase in minimum wage does affect employment, both in theoretical and empirical terms: the colors, lights smells, etc. of the rat maze, if you will. This is rarely the argument posed by the critics of economism, and as such, they engage in ascientific cargo cultism of their own, precisely because they want to raise the minimum wage as a matter of policy.
The nice thing about natural sciences is that they offer little incentive for people other than abstract, theoretical curiosity. I have nothing invested in how rats find their way–unless I have some grand theory about rats’ maze finding skills which would be undermined if rats hear their way through mazes. So I think it’s great to learn that rats have great sense of hearing and they use it in their lives, including, incidentally, how they find their way around mazes. If I want to lower taxes, decrease unemployment, reduce the number of abortions, or raise students’ test scores, I am no longer the detached observer motivated only by curiosity. I become an advocate and I become dumb, blinded by what I want. Advocates make good cargo cultists, but not good scientists because they believe too much. Social sciences offer too much to believe in and, as such, they become too normative too quickly, on one side or another. There is no such thing as a normative science.