What is the relationship between economics, as a social science, and the natural sciences?
The usual argument is that the social and natural sciences are fundamentally different, that the natural sciences are objective in a manner that economists and other social scientists do not and cannot achieve. For Sean Carroll, it’s a matter of consensus versus contamination:
On the very basics of their fields (the Big Bang model, electromagnetism, natural selection), almost all natural scientists are in agreement. Social scientists seem to have trouble agreeing on the very foundations of their fields. If we cut taxes, will revenue go up or down? Does the death penalty deter crime or not? For many people, a lack of consensus gives them license to trust their own judgment as much as that of the experts. To put it another way: if we talked more about the bedrock principles of the field on which all experts agreed, and less about the contentious applications of detailed models to the real world, the public would likely be more ready to accept experts’ opinions. . .
. . .political inclinations and other non-epistemic factors color our social-scientific judgments, for experts as well as for novices. On a liberal/conservative axis, most sociologists are to the left of most economists. (Training as an economist allegedly makes people more selfish, but there are complicated questions of causation there.) Or more basically, social scientists will often approach real-world problems from the point of view of their specific discipline, in contrast with a broader view that the non-expert might find more relevant. (Let’s say the death penalty does deter crime; is it still permissible on moral grounds?) Natural scientists are blissfully free from this source of bias, at least most of the time. Evolution would be the obvious counterexample.
The problem is that commentators like Carroll continue to carry around a conception according to which the natural sciences are free of bias, and that natural scientists are able somehow to carry out their work independently of the society in which they work.
It’s a view of natural science disputed by the participants—Steven Rose, Andy Rowell, and Connie St louis—in a recent Red Pepper roundtable on science and society.
‘Actually I don’t think there’s any such thing as science,’ states neuroscientist Professor Steven Rose at the start of Red Pepper’s roundtable on the subject. He pauses while we contemplate his opening remark. ‘There are only “sciences” – different ways of approaching and trying to understand and make sense of the world.’
Science is still popularly viewed as a uniform realm of objectivity: an organised way of knowing the world in the form of testable explanations and predictions. Rose offers a different definition: ‘Scientific questions don’t exist outside of the social framework in which those questions are phrased, so the sorts of science that are done in one culture, one social context, one historical epoch, are very different. There’s no science outside the society in which it is embedded.’
The link to the audio version of the conversation is here.
occasional links & commentary 
I’ve been influenced for a long time by some of the terminology of the Kuhnian approach — a field, defined by the currently dominant paradigm of thought (which generates its own forms of “normal science”), periodically coming into crisis, which may or may not then be resolved by a “revolution” and the emergence of a new paradigm, after which “normal science” resumes on the new basis. (And “objectivity,” if it has meaning at all, is entirely a property of the practices of each “normal science.”) That’s Kuhn on “natural sciences.” Lots of room for social constitutivity there, for any of us who want to think about ideas that way.
“Social sciences” don’t fit quite so neatly, economics in particular, since our field has been more-or-less permanently in crisis, in the sense that different and incompatible paradigms have been simultaneously present basically from the beginning (dueling, criticizing, rising and falling in influence, but persisting). Weirder still, each continues with its own varieties of “normal science” even as they contend, each tending to see the other guys as the ones who have a “crisis” to deal with.
Sometimes, though, like the brief period after the financial crash, even the normal scientists within the dominant paradigm start feeling abnormal, and worried. Unfortunately, most of them manage to take a mental aspirin and wake up later convinced it was all a bad dream and normal science can go on largely as before. (Government did it, real supply shocks did it, ….)
Among all the other things we do and try to do, it’s a task for the rest of us to keep rocking the boat, keep making it uncomfortable for the mainstream to feel “normal” and “objective.”