Aside from containing a brilliant exposition of how blogospherical “rebuttal” actually works — basically endless posts by halfwits repeating that X (an eminent scholar) is an ignoramus because X has contradicted the received wisdom of a tribe — this post by Dave Graeber at Naked Capitalism has to be one of the most informative and entertaining pieces I’ve read in a long while. What happens when the findings of anthropologists about earlier societies clash with the a priori assumptions of economists about how things _must_ have happened? Well, you can guess. The really interesting stuff is in the anthropological detail, so read the whole thing, as they say, but I’ll just quote Graeber on economics and scientific method:

bq. Murphy argues that the fact that there are no documented cases of barter economies doesn’t matter, because all that is really required is for there to have been some period of history, however brief, where barter was widespread for money to have emerged. This is about the weakest argument one can possibly make. Remember, economists originally predicted all (100%) non-monetary economies would operate through barter. The actual figure of observable cases is 0%. Economists claim to be scientists. Normally, when a scientist’s premises produce such spectacularly non-predictive results, the scientist begins working on a new set of premises. Saying “but can you prove it didn’t happen sometime long long ago where there are no records?” is a classic example of special pleading. In fact, I can’t prove it didn’t. I also can’t prove that money wasn’t introduced by little green men from Mars in a similar unknown period of history.