Conclusions

Two things are remarkable in general about the mainstream theories of economic growth judged from a more heterodox perspective. First, there is very little that is established and undisputed about economic growth. As certain literature traditions of Marxian and ecological economics (Daly, 1968; Georgescu-Roegen, 1975a , b; Minsky, 1980; Smith, 2010) show, it is even disputed if economic growth (1) really exists and (2) is a good thing at all. However, even what the different approaches to economic growth claim or imply to know is still rather meager: for more mainstream economics this seems to be limited to statistical relations of certain country-level macroeconomic data, hence the conclusion that different macroeconomic data series relate and correlate in certain ways. This is what is both the theoretical core and the focus of empirical justifications from ¹ Solow (1956, 1957) to the theories of endogenous growth (Cass, 1965, 1966; Uzawa, 1965; Lucas, 1988). Some newer and more sophisticated approaches add aspects of simple microfoundations like perturbations as the origin of cycles (Lucas, 1972, 1975, 1981), non-linearities (Romer, 1986), and the effect of technology and technological change (Aghion and Howitt, 1992). Evolutionary growth theory (Nelson and Winter, 1974, 1982a, b; Nelson et al., 1976; Conlisk, 1989; Silverberg and Lehnert, 1993, 1994) and other alternative approaches ² are more serious in including microfoundations, thereby emphasizing the importance of direct interdependence, innovation, technological change and technological diffusion. This results in more robust agent-based models that also imply certain simultaneous developments on the micro-level, such as the industry structure, research investment, etc. (which indeed have been extensively studied by Nelson and Winter (1982a, b)). Still, the real microstructure of firms, entrepreneurs, employees, etc., as well as the microfoundations for many macro-level phenomena are somewhat obscure.