>I'm actually not a Kuhnian on these issues, but I am trying to see how far >Kuhn's theory goes in accurately describing economic research. Is it >really true that there aren't reigning paradigms in meteorology?
That is not what I meant. Of course there is. Its thermodynamics. However, to an outsider it looks to impose about as much structure on weather modeling as the notion of general equilibrium imposes on macro-modeling - - that is that the devil is in the details, big models can be less informative than the careful eye of a specialist in local phenomena, and simple models which are consistent with, but not based explicitly on physical theory, do almost as well as very big very complex models with a very tight relation to the theory. Also, I doubt there has been anything that looks like a paradigm shift in meteorology though I suspect there have been changes in "fashion" with respect to how weather is predicted. > I should >note that experimental econ seems to be developing in a very Kuhnian >fashion. In what sense. I would say its inverted. In Kuhn new ideas come into a profession because young people feel free to work with them while the dinosaurs continue doing what they do. With behavioral economics young people are only now starting to do it after a bunch of people with tenure fought like heck for 20 years to get the ideas accepted. >> the hallmark of modern physics. Sure there are physical problems where >> chaos and complexity cause the same sorts of problems that economists >> have dealing with the economy, but they aren't at the core of the >> discipline the way they are in economics. Thus I think that a lot of > >Some core parts of physics deal with complexity - how about statistical >mechanics? Is there a macro counterpart to statistical mechanics? Not sure what you mean by this, but I suspect that is exactly what the stochastic mechanics of the typical general equilibrium model is about. But you miss my point. I'm arguing that the phenomena physicists study at the core of the discipline are amenable to sufficiently exact theory and exact measurement that you can have decisive paradigm shifts driven by anomalous research results. Economic theory is not as precise so measurement can't provide the sort of strong evidence that one sees in core physics. Of course Kuhn's point is that research results aren't decisive in physics either. That anomalous results can always be reinterpreted to fit with the old paradigm and that therefore paradigm shift is a social phenomena rather than a purely logical phenomena. However, what I'm suggesting is that sharp divisions between "paradigms," and paradigm shifts aren't a good way of thinking about how we progress in economics. One could say that economics has never had a paradigm shift. ! We went from pre-science to science with the marginalist revolution and have been doing normal science ever since. I would argue that pre-1970s macro was fully within this tradition within economics though the connections to price theory were verbal rather than rigorously theoretical and allowed verbal theorizing about behavior that was less than perfectly rational. The changes that took place with respect to micro-foundations in the 70s and 80s may look like a paradigm shift but I would argue that they are not. The changes preserved the fundamental notion that the economy should be thought of as a general equilibrium system with markets moving between equilibriums as shocks impact the system. What changed was the specifics of how the equations of the general equilibrium model were derived, estimated and rationalized. While this didn't represent a sea change in the scientific view of the economy, it did represent a sea change in methodology and a sea change in the relative pow! er of the two main ideological camps in economics. For a while the models where tight ties to basic price theory ensured welfare results that were anathema to interventionist liberals. Since about 1985-1990 things have been swinging back the other way with more and more accommodation of rigidities into mainstream (academic) models (largely driven by the inability of models without such rigidities to fit the data). However, it is my distinct impression that there is still a large gulf between practitioners of the different schools. In this sense I think that macro is still quite fragmented. Talking about paradigms and paradigm shifts obscures what I think is the real dynamic. In the 70s and early 80s a confluence of forces including the difficulty Keynesians had with stagflation, but more importantly the internal drive of the profession to insist on tight connections between rational actor models and empirical research, led academic economists to abandon the old tradition of approximating the macro economy with linear equations meant to captur! e the behavior of different markets without explicit micro foundations. Starting in some sense with the failure of rational expectations theory to explain the profound real consequences of the contraction of the money supply in the early 80s, the continuing inability of rational-expectation/RBC models to account for a wide range of empirical phenomena has led to the incorporation of various institutional and behavioral rigidities into models. If I were in a provocative mood I would say that modern macro has almost recovered the lost wisdom that it threw away in a misguided fools errand that began in the 1970s. Of course it will be nice if we finally secure micro foundations for macro economics even if we just end up back where we started. However, I will still mourn all the wasted energy and the progress that could have been made if we hadn't taken this 25 year side track. >Is the difference between monetarists and post-Keynesians smaller than >between post-Keynseians and Austrians? Austrians don't even accept >equilibira theory as a starting point of economic analysis. Post-Keynesians are different from neo-Keynesians. Post-Keynesians are non-mainstream leftists with no coherent view of the economy. They are united only in their opposition to mainstream economic theory. They play no roll in mainstream economic discussions. Its hard to talk about differences between Austrians and post-Keynesians since post-Keynesians (at least) have no well enunciated coherent view of economics. If you mean neo or new-Keynesians then the differences between them and new-classicals (the heirs to 60s monetarism) is minor compared to their differences with Austrians or post-Keynesians. But so what? Post Keynesians and modern Austrians play absolutely no roll in mainstream economics either in the development of ideas at major universities, and in major journals, or in the practice of economics in either important commercial forecasting companies or government agencies. They are completely ignored by the core of the profession. - - Bill Dickens William T. Dickens The Brookings Institution 1775 Massachusetts Avenue, NW Washington, DC 20036 Phone: (202) 797-6113 FAX: (202) 797-6181 E-MAIL: [EMAIL PROTECTED] AOL IM: wtdickens
