Professor Mayer argues that there is room in economics for both highly formalized theory and for the less formal theory that predominates in the natural sciences. But economists generally fail to distinguish between these two types of theory. As a result, they often act as if the strength of an argument depends on the strength of its strongest link. They misallocate effort, polishing those parts of the argument that tend to be formalized, while paying insufficient attention to the others. Drawing on public choice theory, Mayer shows how this emphasis on the strongest link has distorted research particularly in new classical theory. He advocates stricter econometric testing, showing that many procedures currently used are only soft tests.