One of the puzzles that accompany this gruelling economic crisis is why neo-liberal economic thinking, which when applied caused the crisis and has delivered very little to so many, remains the dominant paradigm in economic policy making and has managed to turn a disaster for practitioners of that ideology into a triumph. How is it that the leading voices now are preaching exactly the same policies that caused the crisis as the solution to the crisis. Is there that much asymmetry? I noted a recent comment on my blog (Tom) that raised issues relating to the philosophy of science along the lines of how are we to judge whether the mainstream macroeconomics paradigm has failed. I understand the demarcation issues involved and the problems of “truth testing”. But we can take a more simple approach to the question. Here are two ways we know that the mainstream approach failed – they didn’t have a clue what was happening in the years leading up to the crisis and now they are scrambling in a stunned state to add banks and financial markets to their defective models. The problem is that they are just building more defective approaches. But the continued dominance demonstrates that their failures are not yet fully understood.