As the planet approaches 8 billion, international debate on population will be ignited again, and as with 7 billion, 6 billion and 5 billion, discussion will still circle around Thomas Robert Malthus and his Essay on the Principle of Population (1798). Why does a controversial text from the classical political economy canon, and from a pre-industrial time, endure as a touchstone? Malthusian ideas and their discontents have endured as a policy benchmark. They have done so across massively diverse global polities, cultures and languages (India, China, Japan, Australia), for leaders and policymakers across time (Nehru, Mao, Deakin), and for the world’s key global thinkers (Mill, Marx, Keynes). But this is not just a matter of the past. Experts and lay commentators, politicians and the public, proponents and opponents, continue to benchmark their views against Malthus. International economists repeatedly ask: ‘How relevant is Malthus for economic development today’? (Weil and Wilde, 2010); ‘Does Malthusianism hold true’? (Sachs, 2015). The answers are still strongly ‘yes’ and strongly ‘no’. Yet the context has now changed, partly because of climate change and sustainable growth agendas, partly because fertility rates have, and are, continuing to fall across the globe. This essay by a modest and unassuming man is certainly a work that shaped the world.

Professor Alison Bashford, FAHA, FBA is Director of the Laureate Centre for History & Population at UNSW, Sydney. Previously she was Vere Harmsworth Professor of Imperial and Naval History at the University of Cambridge. She is author of several books on modern population thought, and co-editor most recently of New Earth Histories (Chicago, forthcoming). She is currently completing a book on the Huxleys, From Genesis to Genetics with a Scientific Dynasty (Penguin Random House). Alison Bashford was awarded the Dan David Prize in 2021 for her work on the history of health and medicine.