One point that particularly saddens me is the utter misunderstanding of growth by economists, because they go with the easy assumption first (GDP growth is a representative value), then with the oversimplification about the sources of growth, particularly the salient dependency of available cheap energy to sustain growth (see for instance http://netenergy.theoildrum.com/node/7069#more ).
Then they generally proceed by forgetting that Adam Smith wrote his books in a time of immemorial non existent or extremely slow growth, which change radically the view. Market efficiency is to be considered in a radically different manner when the general environment is economically quite stable, which naturally should prevent concentration, for instance.
This is just to mention a couple of things that struck me, I generally don't pretend to know much about economy, though.
I think one of the epistemological problem with economics is that it's almost impossible to run experiments(except maybe college kids experiments), and it would probably be irresponsible to run experiments on whole nations. That why some economists approach it by using entirely deductive logic as a mean of study.
It's also true of cosmology, though cosmological errors won't ruin people lives :) If you haven't read "the shock doctrine", it states that actually there was many economic experiments, in Chile and other countries, usually for the worse... Well USSR made some large scale experiments too, from 1917 to 1921, then 1921 to 1927.
* when the udssr collapsed for real, he said there will be a new enemy: it will either be the green party or islam.
* his recent prediction: the american empire will fall before 2020. he usually continues arguing the american republic will be better.
johan galtung is doing "integrative assesment". he is taking into account the non-uniformity observed in some situations. and he considers different attitudes influencing each other.
one example: when the avantgarde left the church, they turned to science. why does science describe the world in terms of perfection? it is easy to see, he says - because "god's creation was perfect".
Others, like the Austrian economist Ludwig von Mises predicted the death of the Soviet Union and he has dealt with Red Vienna. He also thought that soviet style economy wouldn't work.