David Sloan Wilson's econ critique
In any case, I noticed David Sloan Wilson is writing a series of posts criticizing econ as a whole, and I thought I'd go through one of them and see what I thought was right, and what I thought was wrong. Wilson can get a little grandiose, likening the econ profession to the orcs of Mordor and himself to Frodo. But let's look past that and talk about the substance. Here are a few points in Wilson's essay that I don't completely agree with.
Wilson:
Economists were very smart, very powerful, and they spoke a language that I didn’t understand. They won Nobel Prizes...Nevertheless, I had faith that evolution could say something important about the regulatory systems that economists preside over, even if I did not yet know the details. After all, financial markets and other regulatory systems are products of cultural evolution, based on psychological processes that evolved by genetic evolution.Like I said a while ago, I'm not as confident that evolution is the key to economics. Wilson has spend his career thinking about evolution, and when you have a hammer, everything looks like a nail. But the analogy between cultural evolution and biological evolution is only a loose one - nobody yet knows how cultural traits get passed on, or even how to define those traits. And there's no guarantee that the principles involved are similar to those that hold in biology. As for genetic evolution being important for economics, that's possible, but I think the overreach of evolutionary psychology - a field that gets criticized as much as econ itself - should give people pause. So I'd be cautious with the cross-disciplinary analogies. But hey, it's surely worth a shot. I don't want to be a naysayer. Give it a try!
Wilson:
Like the land of Mordor, [econ] is dominated by a single theoretical edifice...The edifice is based upon a conception of human nature that is profoundly false, defying the dictates of common sense, before we even get to the more refined dictates of psychology and evolutionary theory. Yet, efforts to move the theory in the direction of common sense are stubbornly resisted.I'm not so sure I like the emphasis on common sense.. Science usually places a premium on counterintuitive results, and "counterintuitive" is the opposite of "common sense". If common sense was a good guide to reality, scientists wouldn't be nearly so useful, would they? The list of amazing science facts that seem to defy common sense is long - How can matter be both a particle and a wave? Etc. etc.
In econ, common sense might that when two countries trade, one wins and one loses, but the theory of comparative advantage shows that it's very easy for that not to be true. I'm not saying that comparative advantage is always a good theory of trade, but it certainly shows that demanding that all econ theories conform to common sense is overly restrictive.
Wilson:
There is plenty of dissent among economists, and some of the best are working the hardest for change. The folks who award the Nobel Prize in economics don’t like the edifice that much either, and often add their weight by awarding the prize to the contrarians.The first sentence is definitely true. But I'm not sure Wilson is right about the Nobel a force for rebellion. The Nobel has gone to quite a lot of people whose work forms the very foundation of the "edifice" that Wilson talks about. In fact, the vast majority of the prize winners from the past three decades have worked within the rational, individual-choice framework that Wilson doesn't like. In fact, people like Thomas Sargent, Ed Prescott, and Bob Lucas built the very modern macroeconomics that Wilson recoils at...and they got Nobels for it.
Wilson:
Economists were much more closely attuned to common sense and evolutionary theory before the volcano erupted. Adam Smith observed that people following their narrow concerns somehow combine to make the economy work well, as if guided by an invisible hand. Today we use terms such as emergence and self organization to describe this phenomenon. It is spectacularly demonstrated by social insect colonies.I also think this isn't really right. Smith was certainly not inspired by modern evolutionary ideas, since On the Origin of Species was published almost a century after The Wealth of Nations. It's not at all clear that Smith believed the "invisible hand" worked analogously to an insect colony; he didn't really specify the mechanism. (Not that insect colony self-organization is a good example of evolution in action, anyway - though ants certainly evolved the biological means to self-organize, the process by which they do so on short time scales is not really very similar to biological evolution in most respects.) In fact, the general equilibrium economics that Wilson doesn't like is supposed to represent Smith's invisible hand.
Wilson:
The people who inhabit the economic models, often referred to as Homo economicus, are driven purely by self-regarding preferences. Mathematically, this means that they care only about maximizing their own interests without reference to anyone else’s interests. What I want cannot depend upon what you want.Actually, that's not right. When externalities are present, people's utility can depend on other people's consumption. Externalities are very common in mainstream economics, and the concept is taught in every (good) econ undergrad course.
Wilson:
Next, people who inhabit the mathematical kingdom are infinitely wise in pursuit of their self-regarding preferences.This is, sadly, true. Economists have played around with a number of ways to drop this assumption, but they haven't reached a consensus yet, and - in my opinion - still have far too much trepidation about modeling incompletely-rational behavior.
Wilson:
Once again, these absurd assumptions were driven not by ideological bias but by the tyranny of mathematical tractability. The theory couldn’t be pushed in the direction of common sense because it would become impossible to grind through the equations.This is partly true. Ideological bias probably does play some part in economists' unwillingness to allow irrationality, or things like social preferences, into their models. Tractability concerns can play a role too. But there's also the underlying problem that it's just very hard to make a general mathematical model of human behavior.
Anyway, I like that Wilson is thinking about economics, and saying provocative, challenging things. There's really very little downside to saying provocative, challenging things, as long as you're not saying them into the ear of a credulous policymaker. At the very least, Wilson will provoke some fun arguments with economists. At best, he'll inspire some to start tinkering around with models based on evolutionary principles. Who knows - that might even get some good results someday!
But in the meantime, I'll keep trying to help nudge Wilson toward an accurate picture of what's going on in the econ world. After all, if you want to be Frodo and sneak into Mordor, you should make sure you have a good map - otherwise you might just end up in New Jersey.
Updates
David has a response up at Evonomics. He writes:
What stands out in Noah’s critique of my piece is its complacency. It’s like he’s discussing the arrangement of deck chairs aboard the Titanic. There is no sense of urgency about the failure of orthodox economics theory and the need to place it on a new foundation...
Noah misses the point when he observes that evolutionary psychology, the study of cultural evolution, and their applications to economics are nascent enterprises. He seems to think that they can be ignored until they have reached some undefined state of maturity. He doesn’t get that when your ship is sinking, you need to build a new ship and move onto it as soon as you possibly can...I wouldn't say I'm complacent at all. Macroeconomics obviously needs some big changes - the crisis and Great Recession showed that, though it should have been apparent long before. The "boat" of macro definitely has substantial holes in its hull.
OK, so suppose you decide that the boat can't be patched up or repaired, and it's time to abandon ship - to completely change the way we do macroeconomics. How do you know which boat to jump to? If you jump into a non-seaworthy boat, you could be in even bigger trouble than before.
David assumes that evolutionary thinking is a seaworthy boat for macroeconomists to jump into. The basic argument seems to be that evolutionary thinking has been successfully applied in many other areas - or at least, that David has made a career out of claiming that it can be so applied. He writes:
My life’s work gives me a panoramic view of the human-related disciplines such as religion, sociology, the humanities, and the philosophical tradition of pragmatism, to list a small sample. The very fact that I and like-minded colleagues can do this (it is a perspective, not an individual talent) suggests that evolutionary theory has a generality that orthodox economics aspired to and failed to achieve.Well first of all, just because David has made a bunch of similar claims about how evolutionary thinking can be applied to a bunch of other disciplines doesn't mean those other claims were right. In fact, not knowing much about religion, sociology, or the humanities, I'm not in a position to evaluate them - nor, I suspect, are most of David's readers. But if there's a general consensus that evolutionary thinking has successfully improved and transformed most fields of humanities and social science, I'm not aware of it. I should probably read more.
But more importantly, there's just no reason to think that a conceptual framework that works in one discipline should work in another. Why should ideas that work for religion -- whatever that even means -- also work for economics?? It just doesn't make sense. There's no grand theory-of-theories that tells us that all disciplines and all phenomena must act according to some basic universal underlying principles. Physics methods don't usually work for biology. Why should we think that biology methods work for economics?
Yes, mainstream economic models weren't a lot of help in the crisis or the recession. But how confident can we be that making economic policy based on evolutionary analogies would be any better? Before I believe that, I'll want to see some good hard evidence.
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