Andy Haldane (Executive Director of Financial Stability at the Bank of England):
“Again, I have an evolutionary story as to why economics ended up in this place. I don’t think it’s because people were taking pay-checks from consultants or countries to cook the answers. I don’t think for a minute that was the core of it. It was driven by the quest for certainty, and mathematisation of economics was a means of achieving that certainty. It was the desire to have the laws of economics as well-defined as seemingly were the laws of physics or other natural sciences, as a basis for policy experimentation. They were all good reasons for wanting to make the discipline rigorous and robust.
I think one of the great errors we as economists made in pursuing that was that we started believing the assumptions of economics, and saying things that made no intellectual sense. The hope was that, by basing models on mathematics and particular assumptions about ‘optimising’ behaviour, they would become immune to changes in policy. But we forgot the key part, which is that the models are only true if the assumptions that underpin those models are also true. And we started to believe that what were assumptions were actually a description of reality, and therefore that the models were a description of reality, and therefore were dependable for policy analysis.”