Malthus’s Theory of Overpopulation (225 Years Later)

At the end of the eighteenth-century, Thomas Malthus, an English clergyman, argued that populations, if left to their own devices, grow past the point of resource sustainability, leaving many to live without. His argument, which he elaborates in his Essay on the Principle of Population, is based on two suppositions: First, ‘that food is necessary to the existence of man’, and second, ‘that the passion between the sexes is necessary, and will remain nearly in its present state’. Assuming these suppositions as granted, Malthus argues that ‘the power of population is indefinitely greater than the power in the earth to produce subsistence for man’:

Population, when unchecked, increases in a geometrical ratio [doubling itself every twenty-five years]. Subsistence increases only in an arithmetical ratio. A slight acquaintance with numbers will show the immensity of the first power in comparison of the second […] I see no way by which man can escape from the weight of this law which pervades all animated nature

As Robert J. Mayhew writes in Malthus: The Life and Legacies of an Untimely Prophet, ‘Malthus’s Essay was an immediate succès de scandale and has never been out of the public consciousness for the two hundred years since it was written’. Its premise has inspired ‘prompt acceptance or pre-emptory rejection’ — with admirers such as…