Can you name anything that Krugman said that was both a) novel and b) true? Can anyone? Did he really say anything about trade that wasn't known to Alexander Hamiliton? Did he say it in a way that wasn't already said more eloquently by Jane Jacobs? Sure he added a lot of mathematics, but the Wikipedia article is pretty damning on that front: "The econometric evidence for NTT was mixed, and again, highly technical. Due to the time-scales required and the particular nature of production in each 'monopolizable' sector, statistical judgements have been hard to make. In many ways, there is too limited a dataset to produce a reliable test of the hypothesis which doesn't require arbitrary judgements from the researchers." http://en.wikipedia.org/wiki/New_Trade_Theory

In other words, Krugman's contribution is a lot of math that has never been shown to work. When you add math to a theory in a way that does not improve people's understandings of the issue, you have not added to the world's store of knowledge.

the problem is that it is impossible to audit said models. unlike real science the social sciences can't isolate variables in order to test predictive power.

Like e.g. palaeontology, economists can't do experiments. You must remember that about economy.

I've read a bit too much criticism of economy as a science using the same argument you see from creationists against palaeontology. (That is, assumptions that all researchers are idiots and/or in a conspiracy against the creationists/left wing extremists.)

well pure paleontology is abduction is a sense. but the thing about paleontology is that it is based on biology in which we can do experiments.

Economy is arguably based on cognitive psychology and game theory. (A bit less strictly, but it should even out with all the lacking environmental parameters in paleontology...)