Factor-Eliminating Technical Change

Endogenous growth requires that non-reproducible factors of production be either augmented or eliminated. Attention heretofore has focused almost exclusively on augmentation. In contrast, we study factor elimination. Maximizing agents decide when to reduce the importance of non-reproducible factors. We use a Cobb-Douglas production function with labor and capital as factors of production. There is no augmenting progress of any kind, whether Hicks, Harrod, or Solow neutral, thus excluding the standard engine of growth. What is new is the possibility of changing factor intensities endogenously by spending resources on R&D. The model allows derivation not only of the balanced growth solution but also of the full transition dynamics. There are two possible ultimate outcomes, depending on parameters and initial conditions. The economy may evolve into one that uses both labor and capital, or it may evolve into one that uses only capital. The first outcome is the standard Solow model; the second is the AK model of endogenous growth. The model thus provides a theory of the endogenous emergence of a production technology with constant returns to the reproducible factors, that is, one that is capable of supporting perpetual economic growth. The transition paths are interesting, allowing non-monotonic behavior of both the capital/labor ratio and the factor shares. An aspect of the transition path that is unique for a Cobb-Douglas economy is that the origin is not a steady state. An economy that starts with pure labor production simultaneously accumulates capital and increases its capital intensity to make the capital useful. The theory thus offers a purely endogenous explanation for the transition from a primitive to a developed economy, in contrast to other existing theories. Several aspects of the transition paths accord with the evidence, suggesting that the theory is reasonable. In contrast to almost all the existing endogenous growth literature, neither monopoly power nor an externality is a necessary condition for endogenous growth. It is sufficient that firms be able to appropriate the results of their research and development efforts.