« the economy is a complex system of interacting individuals — and these individuals themselves are complex systems. Neoclassical economics radically oversimplifies both the individuals and the system — and gets a lot of mileage by doing that; I, for one, am not going to banish maximization-and-equilibrium from my toolbox. But the temptation is always to keep on applying these extreme simplifications, even where the evidence clearly shows that they’re wrong. What economists have to do is learn to resist that temptation. But doing so will, inevitably, lead to a much messier, less pretty view« .