Demographic Metabolism: A Predictive Theory of Socioeconomic Change

This essay introduces a general theory of how societies change as a consequence of the changing composition of their members with respect to certain relevant and measurable characteristics. These characteristics can either change over the life course of individuals or from one generation to the next. While the former changes can be analytically identified and described by certain age- and duration-specific transition schedules, the latter changes resulting from cohort replacement can be modeled and projected using standard models of population dynamics. Building on earlier qualitative work by Karl Mannheim and Norman Ryder, this new theory applies the quantitative tools of multi-dimensional mathematical demography to forecast the future composition of a population according to relevant characteristics. In the case of persistent characteristics (such as highest educational attainment) that typically do not change from young adulthood until the end of life, quantitative predictions about the distributions of such characteristics in the population can readily be made for