Great reading. Microfoundations are great, don't get me wrong. But this obsession over them and the dismissal of everything else as "ad hoc" frustrates me.
Point #3 is very important. This is a big point for me in this particular pet peeve. I hate it when people insist you're missing the complexity and emergent order of the economy by looking at aggregates. When I hear you say that, I automatically discount the extent to which I think you really comprehened the implications of emergent order for scientific analysis. If a system is complex, rooting around to correctly specify all the intricate microfoundations is EXACTLY WHAT YOU ARE UNLIKELY TO BE SUCCESSFUL IN DOING. You are better off getting a good solid sense of the operation of the system as a system than you are tracing your way through the complexity.
9 hours ago