A large empirical literature has documented differences in Schumpeterian profits, both among firms in single industries and between firms in different industries. Theorists have proposed various institutional and strategic factors to account for such differences but have had relatively little to...

We do two things in this paper. First, we put forward some elements of a microeconomic theory of technological evolution. This involves adding nascent (essentially undiscovered) technologies to the existing technologies of neoclassical production theory, and, more importantly, expanding the...