Work: A Deep History, from the Stone Age to the Age of Robots

by James Suzman

Malthus observed that agricultural output only ever grew “arithmetically,” whereas population, which he calculated (erroneously) tended to double naturally every twenty-five years, grew “geometrically” or exponentially. He believed that, as a result of this imbalance, whenever improvements in agricultural productivity increased total food supply, peasants would inevitably set about creating more mouths to feed, with the result that any per capita surplus was soon lost. He viewed land as an ultimate constraint on the amount of food that could be grown, noting that the marginal utility of additional labor in agriculture diminished rapidly, because having ten people work a small field of wheat that was once easily managed by one would not result in ten times the wheat, but instead result in a diminishing share of its yield for each of those who worked it. Malthus was of the view that the relationship between population and productivity was ultimately self-regulating, and that whenever population growth overtook productivity, a famine or some other form of collapse would soon reduce the population down to a more manageable level.