A four-part treatise on the subject of population and the rise of nations

Abstract

The interdependence between population and the rise of nations has long vitalized scholarly and statecraft studies. Within the fields of economic growth and economic history, there have been proliferations of modeling/technical skills and historical demographic-economic estimates in recent years. This provides opportunities to examine the relationship between demography and development/divergence in the context of world economic history through unified growth theories and model-based simulations. In pursuing this ambition in a systematic manner, this treatise is divided into four stand-alone yet complementary chapters.

The first chapter “Industrious Selection” develops a unified growth theory to reconcile development (Agricultural Revolution, Structural Transformation, Industrial Revolution, Industrious Revolution, Demographic Revolution) and divergences (Little Divergence, Great Divergence) in Eurasia in the past two millennia. We introduce the Industrious Selection mechanism, where more industrious individuals gradually dominate population composition through humans’ conscious maximization activities. It raises working hours, improves production efficiency, and accelerates development. The Black Death expedited Industrious Selection in late-Medieval Europe. Together with the population scale effect, our theory reconciles British development and Eurasian economic divergence during AD0-AD2000. The second chapter “Rise of Women in Unified Growth Theory” posits that the advent of feminism, industrialization and demographic transition are integral components in a nation’s development. We develop a two-sector bisexual unified growth model to replicate French development during AD1400-AD2100. This chapter complements the first one by restoring women’s role in economic history: female empowerment would hamper fertility, lower agricultural employment share, and decelerate development; development that checks fertility would raise female labor-force participation and women’s (economic) power. We reconcile the U-shaped evolution of women’s socio-economic status, the absence of a Post-Malthusian regime, the importance of fertility control and innovation in the French development process. We also explore policy implications for Madagascar today. The third chapter “Population Growth and Structural Transformation” provides a theoretical foundation on which population growth induces structural transformation, which is a key adjustment mechanism in the first two chapters. When sectoral outputs are consumption complements, population growth pushes production factors towards the sector with stronger diminishing returns to labor through the relative price effect. Our theory points to a two-stage development process: in early development, population growth shifts production factors to the farmland; when agricultural productivity growth picks up, production factors move out from it. We simulate agricultural-manufacturing transformations in pre-industrial England and the modern United States. The fourth chapter “GeoPopulation-Institution Hypothesis” develops another unified growth theory to account for development and divergence in the Western Hemisphere to complete our understanding of world economic history on a grand level. We posit a unified growth model with transatlantic migration and slavery trade to reconcile demographic-economic development in the Thirteen Colonies/United States during AD1700-AD1860. Then we apply the model across American regions/countries, and propose the GeoPopulation-Institution hypothesis to explain divergence: whenever its geographic or political environments relatively favored the buildup of Black slaves (or non-White forced labor), through slavery institution that disincentivized the Blacks to make improvements, a region/country was likely to suffer a reversal of fortune during the colonization era (AD1492-AD1860).