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I hope to have a more complete reply to Jim Manzi’s assessment, but I wanted to make a couple of remarks off the cuff.

One Manzi says

Economists will sometimes make explicit claims that “the economic science says X,” and will more frequently make implicit claims for scientific knowledge by flatly asserting the known truth of some predictive assertion. This is normally a statement made around some specific policy question – we should (or should not) execute the following stimulus program; we should (or should not) raise the minimum wage right now, etc.

. . . all we have is an informed opinion of the type we might have from an expert historian rendering an opinion about something the likelihood that Libya would revert to an authoritarian government within ten years if it overthrew Gaddafi

Its important to distinguish between economics as science and economics as a policy driver. Manzi is focusing on economic statements that are made as policy drivers and saying it is only informed opinion. Yet this informed opinion is what is being offered. Economic science is a different enterprise.

Saying that we should execute the following stimulus program is much different than saying that we have an established scientific principle that stimulus has such-and-such effect. Contrary to intuition the first statement is far, far weaker. This is why “economic science says” is heard less frequently than “we should.”

Even setting aside personal values, “we should” is, by its very nature, a statement about subjective probability distributions. It is saying I believe that the distribution of possible effects in the stimulus world is – by some metric – superior or inferior to the distribution of possible effects in the non-stimulus world.

This requires only that you have some evidence – any evidence – that the stimulus is more likely than not to do things that you judge to be good or bad.

As such, saying that “we should” do something does not make an implicit claim about factual knowledge. Moreover, no one advising the government acts as if it does. Hardcore proponents of democracy assert that “we should” follow the advice of a group of people on the grounds that they have all survived to the age of 18. This is hardly a claim to any sort of scientific knowledge.

Now, I know Manzi’s complaint will be that economists come waving models and multipliers as if their recommendations were based on well established science. However, this is not how economists have traditionally offered their evidence. Economists are famous for refusing to draw firm conclusions and offering loads of caveats.  As Harry Truman famously said

Give me a one-handed economist! All my economics say, ”On the one hand… on the other.

That scarcely represents overselling policy recommendations as scientific knowledge. In recent years some economists, myself included, have responded to the near relentless pressure for clear concise statements with

Our model suggests . . .

I believe you will find this statement repeated over and over again in congressional testimony. No “there is”, “there will be”, “it is a scientific fact.”

Our model suggests, gives you one interpretation. Many economists would love to stand before legislatures and give an hours long lecture on all of the evidence and competing possibilities. However, you get 20 minutes and the audience will demand that your story have a moral.

At the end of a presentation, more than once, the very first question has been this exact phrase: That’s all very interesting professor, but are you saying we should do this or not?

It’s a joke among my friends and family that I begin the answer with “Well, . . . “ Again, no false mantle of scientific certainty.

Now, lets consider economists as pundits. Aren’t they asserting models as facts. Very rarely.

Take Paul Krugman.

Conservatives will no doubt have noticed that one of Krugman’s major themes is that their point of view is stupid. One might be inclined to think that this is a rude way of saying “you do not have access to the scientific knowledge that I do”

It is not. It is a statement about what he thinks of your intelligence and ability to draw well formed conclusions.

He is not saying, I have such a deep understanding into the nature of the economy that everyone should listen to me. He is quite literally saying that the statements of conservatives convey such a shallow and imbecilic understanding of the economy that no one should consider listening to them.

He is not claiming the mantle of science, he is claiming the mantle of not being a moron.

On the opposite side of the spectrum, go back and look at the public statements of Milton Friedman. How many times did he lean on the fact that economics had established scientific knowledge that shouldn’t be questioned.

He always began with very simple facts and then drew out a small, compelling story. At worst, he would say “look at the evidence” and then proceed to offer the type of simple statistics that wouldn’t be uncommon in an Op-Ed.

Again, no implicit claim to scientific knowledge, only an implicit claim that reasonable informed people would agree with him.

The public policy statements of economists aren’t assertions of scientific knowledge. They are informed argument and economists present them as such. There is no doubt that economists use their knowledge of economic science to inform their policy arguments. Yet, in making those arguments they are not claiming scientific knowledge that they do not possess.

What you can argue is that economists think that they are smarter than everyone else. Indeed, economists across the political spectrum have made precisely that point. From Greg Mankiw

Larry, Vindicated

A flashback to 2006:

“President Summers asked me, didn’t I agree that, in general, economists are smarter than political scientists, and political scientists are smarter than sociologists?” [former dean Peter] Ellison told the Globe.

Here (via Mark Perry, posted two days ago) are GRE scores by field. Economists rank number 4. Political scientists are number 17, and sociologists are number 23.

In short, Manzi’s true point shouldn’t be that economists falsely assert scientific knowledge were there is none. It should be that we are arrogant pricks. I think many economists would agree.

Slate is the internet’s most notorious house of contrarianism. It’s their formula, and most of the time it’s pretty obvious -at least it was, I haven’t been a regular Slate reader for some time, being turned off by said obvious contrarianism and the frequent wrongness it required. But they may have just lured me back with what might be the most contrarian sentence in the most contrarian article in the history of the internet:

Noncannibalistic people may be the weird ones, cross-culturally speaking.

The article is titled “Bite Me: An Evolutionary Case for Cannibalism”, and quite frankly I love it… the article that is, not cannibalism. Perhaps dropping their bucket into the contrarian well and coming up dry is pushing Slate to extremism. If so, then I think I’m going to reconsider making them part of my daily reading, because that, at least, would be interesting.

h/t @petersuderman

If you had a computer chip implanted in your brain that allowed you to perform complex mathematical computations just by looking at numbers and equations, like an onboard calculator, would you consider that genuine cognitive activity? How about if the computer chip was instead in your pocket? Answering “yes” to the former question is much more intuitive than a “yes” to the latter, but why should that be?

This are questions that occur in the fields of “embodied cognition” and “the extended mind”, and the topic of a recent article in the New York Times. The author of the article, Andy Clark, argues that we should view the theoretical brain-mounted computer chip as “bio-external elements in an extended cognitive process: one that now criss-crosses the conventional boundaries of skin and skull”. Importantly, he argues that iPhones and blackberries function in a similar way that a brain mounted chip would, and so they should be thought of likewise.

I’ve made similar arguments before, and I think that in the not-so-distant future we won’t need thinkers like Andy Clark to prompt us to consider these questions, as technology will place them front and center. Even if you find it absolutely clear that none of todays technologies should be considered cognition, or part of your brain, mind, or self, it will be much less clear as future technologies become more seamlessly integrated with our thought process.

For instance, consider the inevitable scenario I’ve laid out before: micro-computers, visual retinal displays, augmented reality, and neural input devices combined so that you’ve essentially got a brain-mounted computer on virtual floating screens in front of you that you control with your thoughts.   Whether or not using these future devices should be considered cognition and part of our minds will be much trickier than it is with today’s iPhones, especially considering that from everyone else’s perspective “organic thought”, as you might call it, will often be indistinguishable from “computer thought”. “Did he just remember my birthday when I asked if he knew it, or did he look it up?”

Glenn Beck drew (more) attention the other day when he declared on his radio program that he didn’t believe in evolution because “I haven’t seen a half-monkey, half-person yet”. Leave aside for the moment the fact that humans descended from, and in fact are, apes, not monkeys. Let’s give Beck the benefit of the doubt and presume what he meant was that he has never met something in between a human and some monkey-like creature, and here I think I can help him. As you can see in the map below, a mere 7 minute drive from Fox News Studios at Rockefeller Center where Beck broadcasts is the American Museum of Natural History. There Glenn can visit the The Hall of Human Origins and see life-sized dioramas of Australopithecus afarensisHomo ergaster, Neanderthal, and Cro-Magnon. Not only that, but he can also see actual casts of Lucy, the 3.2 million Australopithecus afarensis skeleton, and Turkana boy, the 1.7 million year Homo erectus skeleton.

Now Lucy may not technically be a “half-monkey, half-person”, but as you can see from the picture below of  how an Australopithecus afarensis is believed to have looked, that’s not a half bad description of her.

Of course, lover of science that he is, Mr. Beck may have seen these casts and recreations already, and his skepticism can only be appeased by meeting the “real thing”. Well, he should have said something earlier, because from June through October 2009 Lucy was actually on display at the Discovery Times Square Exposition a mere 7 minute walk from Fox News Studios. He could have gone there on his lunch break.

If Beck wants to see a “half-monkey, half-person” all he needs is a little genuine curiosity and about 30 minutes of free time. Given his talent and zeal for digging up convoluted “proof” of far fetched conspiracy theories, you’d think he be a little better at finding evidence for a legitimate theory like evolution; especially since there’s plenty of evidence right in his neighborhood. Maybe someone should tell him that “Van Jones loves Karl Marx” has been scrawled on a bathroom wall at the American Museum of Natural History. Important evidence like that is sure to draw him there.

In a defense of stimulus skeptics, Jim Manzi offers this appeal to a non-consensus among economists on the issue:

…in a genuinely scientific field which has accepted a predictive rule as valid to the point that there is a true consensus—such that the only reason for refusal to accept it is crankery or, in Chait’s terms, “politics”—you don’t usually see: several full professors at the top two departments in the subject, when speaking directly in their area of research expertise, challenge it; 10 percent of all practitioners in the field refuse to accept it; and the two leading global general circulation publications in field running op-eds questioning it.

Specifically, he cites the fact that the University of Chicago’s Barro, Fama, and Mulligan are stimulus skeptics, and according a survey from Mankiw, so are 10% of all economists. But I don’t think 10% of economists and a handful of high-profile experts disagreeing is sufficient to say there is not a strong consensus.

For economics 90% agreement is a pretty high level of agreement, and I would be surprised to find a consensus much stronger on that on most issues. From a survey of economists by Whaples we can see that “only” 87.5% of economists agree that the U.S. should remove all remaining tariffs and trade barriers, 90.1% believe that employers should not be restricted from outsourcing jobs, 85% agree that subsidies to agriculture should be removed, and the same percent say it about sports subsidies as well. From another survey of economists, 87.5% agree that the U.S. trade deficit is not primarily due to other nations’ nontariff trade barriers, 83.5% agree or agree with provisos that tax policy can affect the long-run rate of capital formation, 93% agree that pollution taxes or tradeable permits are more efficient than emissions standards, 92.9% agree or agree with provisos that flexible exchange rates are effective, and 92.6% agree that tariffs or import quotes reduce the general welfare of society.

Despite the disagreement by 7% to 17% of economists on these issues I would argue that are all accurately characterized as representing as a strong consensus. Whaples calls the agreement in those examples a “consensus” and “an overwhelming majority”, and Fuller and Geide-Stevenson, the authors of the other paper, explicitly refer to those examples as representing a “strong consensus”.

Yet I’m certain that on each of these issues you could find experts at the top 10 economics departments that agree with the minority position. Stiglitz alone will probably disagree with more than half of them, and you won’t have to look hard to find a half a dozen other Ivy League dissenters.

My point is not to disagree with Manzi that a strong consensus means it is okay to call anyone who disagrees with the consensus a “crank” or “politically motivated”, but just to point out that the bar he’s set for a “true consensus” pretty much means that there’s is no “true consensus” on important issues in economics. Then again, he may very well agree with that point.

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