“Many of the models in the literature are not general equilibrium models in my sense. Of those that are, most are intermediate in scope: broader than examples, but much narrower than the full general equilibrium model. They are narrower, not for carefully spelled out economic reasons, but for reasons of convenience. I don't know what to do with models like that, especially when the designer says he imposed restrictions to simplify the model or to make it more likely that conventional data will lead us to reject it. The full general equilibrium model is about as simple as a model can be: we need only a few equations to describe it, and each is easy to understand. The restrictions usually strike me as extreme. When we reject a restricted version of the general equilibrium model, we are not rejecting the general equilibrium model itself. So why bother "testing" the restricted version? If we reject it, we will just create another version.”