Carter, Eric D. (2018), "Overpopulation." In: Companion to Environmental Studies, eds. Noel Castree, Mike Hulme and James D. Proctor. Routledge Press, pp. 76-79. 1.14 Overpopulation Eric D. Carter The global population continues to grow, from about 7.3 billion people today, to an expected 8.5 billion in 2030, and over 11 billion by 2100. While the rate of growth has slowed, overpopulation is still widely seen as a driving cause of current environmental problems and the seed of impending catastrophe. Blaming overpopulation for all kinds of social and environmental troubles has a long and layered history, going back to at least the eighteenth century, and it is hard to understand modern environmental thought and environmental science without full consideration of the debates over the overpopulation issue. History of the population question Modern thought on the population question begins with Thomas Malthus, one of the notable classical British economists, whose Essay on the Principle of Population was first published in 1798. In it Malthus famously asserted that the population of a given country grows at a geometrical rate while food supply expands only arithmetically; thus, eventually, the means of subsistence would reach a natural limit and the result would be, inevitably, shortages, hunger, famine, and epidemics. Even in normal times, population growth depressed wages and deepened the misery of the working classes, leading Malthus to argue that the Poor Laws of England and other forms of economic relief for the poor only stimulated rampant population growth and delayed inevitable crisis. Over the years, Malthus’s ideas were used to justify conservative class interests, the eugenics movement, and callous imperial responses to hunger and famine (Bashford, 2014; Davis, 2001). Yet, Malthusianism was also entangled with struggles for women’s reproductive rights, led by feminists such as Emma Goldman, who proclaimed that the working class could achieve its own emancipation through ‘conscious procreation’, and Margaret Sanger, the founder of Planned Parenthood (Connelly, 2008; Masjuan & Martinez-Alier, 2004). In the middle of the twentieth century, the so-called neo-Malthusians adapted Malthus’s demographic determinism to warn of the exhaustion of land and natural resources more generally, not just the food supply. Best-selling books such as William Vogt’s The Road to Survival and Fairfield Osborn’s Our Plundered Planet (both from 1948) stirred fears that rampant population growth and industrialization were bringing the Earth to the limits of its ‘carrying capacity’ (Robertson, 2012). The over-population thesis became one pillar of the modern environmental movement with the work of Paul Ehrlich, a Stanford University population biologist, whose book The Population Bomb (1968) predicted global environmental crisis. Philosophically, the neo- Malthusians stood out for their conviction that natural laws—the principles of demography and ecology, specifically—governed the fate of a global human society. In imposing a natural-science framework on the dynamics of human political economy, Ehrlich actually brought Malthusian thinking ‘full circle’, since Malthus had inspired Darwin’s evolutionary theory, which in turn served as the foundation for modern population biology (Worster, 1994).