Economists like to strike the pose of a scientist. I know, because I often do it myself. When I teach undergraduates, I very consciously describe the field of economics as a science, so no student would start the course thinking he was embarking on some squishy academic endeavor. Our colleagues in the physics department across campus may find it amusing that we view them as close cousins, but we are quick to remind anyone who will listen that economists formulate theories with mathematical precision, collect huge data sets on individual and aggregate behavior, and exploit the most sophisticated statistical techniques to reach empirical judgments that are free of bias and ideology (or so we like to think).

Update... Reader David Hemmer says,

This got me to thinking, do you consider mathematics to be a science? We really don't have this ingredient -- repeatable experimental verification of falsifiable hypotheses -- either!

Update 2... A hedge fund manager (who has asked for anonymity) writes,

I use a helluva lotta math in my financial industry job... but I’m no scientist.

I recommend that you post your definition of science. It seems clear that some of the difference between you and Mankiw over whether economics is a science arises from differing definitions of the term science. You suggest in your comments on Mankiw that science requires experimental evidence. The definition I use (memorized long ago from Funk and Wagnall's dictionary) makes no mention of experiments:

Science: Any department of knowledge in which the results of investigation are logically arranged and systematized according to general laws and hypotheses subject to verification.

Note that the nature of "verification" is not specified here. Would you consider astronomy or geology sciences? They can't reconstruct what they study. They can't creat a slightly different Milky Way or Earth. Astronomers can't even touch what they study (well, almost can't, anyway; they do send rockets to planets and comets). Your implied definition, which qualifies "verification" with "experimental," is just as valid as mine. Definitions are totally arbitrary. They are never right or wrong, only useful or useless. I don't argue with your definition. I just would like to see it. I suspect that some and maybe even most of the disagreement between you on the one hand and people like me and Mankiw on the other is semantic rather than substantive. All I really care about is whether economics helps us understand the world. Whether it is called "science" doesn't much interest me.

Finally, let me add another remark that may clarify some of the differences between the various sides in this debate. There is a distinction to be made between the nature a science per se and the practice of it. There are a large number of economists who do not behave as scientists, usually because doing so would mean they could not use economics to advance their other agenda, whatever those might be. This is a problem with all science, in fact, and it is especially bad when the results of investigation have any public policy implications (e.g., environmental science, global warming).

Economics has an extreme problem here because essentially everything in economics has policy implicationis. Far too many economists let their policy preferences interfere with the conduct of their science (rather than changing their preferences in response to their scientific findings). That says nothing about economics, only something about the integrity of the economists in question. My sense from reading your blog for quite some time now is that part of your criticism of "economics the field" stems from your frustration with many "economists the phonies." I share with you the latter, and perhaps with this distiction in mind we don't even disagree much on the former, except for the semantic issue mentioned above.

Update 4... Reader Gerald Hanner writes,

Reminds me of an online discussion between some economists I was once monitoring (lurking). At one point an engineering prof pipped up and made this statement: We engineers take our cues from the basic research done by physicists. If you followed the same pattern, you would be taking your cues on human behavior from the psychologists, but you don't. How can you claim to be scientific?

Update 6 [5/19/06]... Reader Greg Ransom, who describes himself as a Hayek scholar, says:

I take Hayek's view that economics is a non-experimental science that succesfully explains undesigned order -- just as Darwinian theory is a non-experiemental science that sucessfully explains undesigned order. The key thing is that Hayek's scientifically sound explanatory strategy is largely unused by the "idiot savants" who populate the econ. departments.

What is more Mankiw's brag points -- i.e. "economists formulate theories with mathematical precision, collect huge data sets on individual and aggregate behavior, and exploit the most sophisticated statistical techniques to reach empirical judgments that are free of bias and ideology..." -- has for the most part nothing to do with the explanatory project of economics outlined by Hayek.

Well, that's a taster of the Hayek view.

The Sacramento's Bee's two main editorials this morning are an amazing misunderstanding of cause and effect.

The lead editorial, "Living Large," was about how California "is enjoying a hefty influx of tax revenues from stock market capital gains and other unexpected sources."

The second editorial, "Where's the Sacrifice," bemoans the extension of the 2003 tax cuts that are responsible for a lot of that money from heaven that California is enjoying.

Taken individually, each of these editorials might make a coherent argument. Putting them together and juxtaposing them makes my head spin.

While you fight the big battles, I'll skirmish out here on the West Coast.

...one of the little boobies they let write editorials for the Times now that Abe Rosenthal is gone decided to celebrate the world of the Nukak tribe last Saturday: "Perhaps you read yesterday's article about members of the Nukak tribe...who walked out of the Colombian jungle and renounced their ancestral ways....According to witnesses, they say they are happy about it....None of which explain the bittersweet feel this story leaves in the reader's [the editorial writer's] mind....We have no clearer idea what it would mean to live a subsistence life in the Colombian jungle than the Nukak have of living even on the fringes of the modern world. [Only, little booby, if you have no intelligent imagination or sense enough to get some anthropological information, so readily available on the Internet. See, presumably the difference between you, and them is that you are supposed to be educated]....it's hard to escape the feeling that their SELF-SUSTAINING EXISTENCE...WAS HOLDING SOMETHING OPEN FOR US, SOMETHING THAT HAS NOW BEEN LOST."

Ah, the romance of the "bittersweet" life of the "self-sustaining existence"! Paradise regained, eh? Breadfruit dropping from the trees; fresh, silvery, fish jumping out of the sea into the waiting pan; the beautiful, brown skinned Gauguin women in their colorful sarongs -- what a life awaits. Oh, yes, the "self-sustaining existence"!

We will tell you what it's like, editorial writer, if you don't have the smarts to get the information yourself.

Let's assume that you are a boy editorial writer and you wake up one morning in the Colombian rain forest as part of the Nukak tribe. You've gotten your wish. It's true that you don't have to worry about that $600,000 mortgage anymore. Your new home is whatever you can see before your eyes -- roots, vines, trees, lizards -- all mortgage-free. You won't have to worry about whether Social Security will last until you turn 65, because you won't turn 65. The elders of the tribe rarely get to be older than their forties -- extinguished by malaria, fatal accidents while racing through the jungle after tonight's dinner, and sometimes eaten by a family of crocodiles while fishing...

ABIDJAN (Reuters) - Days after bird flu was detected in Ivory Coast, hundreds of people were trembling, flapping their arms and clucking like hens.

But there was no cause for alarm -- the outbreak was confined to dancefloors.

The movements which are now the talk of the town in the West African country are the brainchild of a 21-year-old disc jockey DJ Lewis, who invented a dance making light of the deadly virus -- by imitating a chicken in its death throes during a cull.

"When you kill the chicken this is how it dies," he shouts into the microphone as a Saturday night crowd rose from tables of green and brown beer bottles to watch him demonstrate the moves...