Endogenicity of economic growth models

In his celebrated 1956 article, “A Contribution to the Theory of Economic Growth,” Solow calibrated the stylized facts of economic growth observed in the Western developed countries and summed up by Kaldor. Solow reconciled steady-state rate of growth of per capita output with constant capital/output and capital/labor ratios by introducing labor augmenting technological progress and measuring physical labor time in efficiency units. A series of articles have appeared since the mid-1980s, which have substantially extended the neoclassical model of growth theory presented by Solow. Most of these are entitled endogenous in juxtaposition to Solow's model, which is considered and often labeled exogenous. The purpose of this article is to show that this dichotomy is not worthwhile by arguing that the way technological progress enters in Solow's model plays a crucial role. Moreover, the designation of a model need not depend on the way it employs just one element among others.