It is sometimes argued that if economists really understand something, they should be able to predict what will happen next. But oil prices are an interesting example (stock prices are another) of an economic variable which, if our theory is correct, we should be completely unable to predict.
jfleck at inkstain
A few thoughts from John Fleck, a writer of journalism and other things, living in New Mexico
http://dss.ucsd.edu/~jhamilto/understand_oil.pdf
Here is a good url for the paper itself.
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