This essay reviews the development of neoclassical growth theory, a unified theory of aggregate economic phenomena that was first used to study business cycles and aggregate labor supply. Subsequently, the theory has been used to understand asset pricing, growth miracles and disasters, monetary...

This work seeks to answer the "population question," i.e. the effect of population growth on production per capita. This question has lingered in economic thought for centuries and to this day two general lines of thought can be identified, which might be marked as the "optimist" and the...