When Keynes Pondered Malthus

In a conversation with Clifford Geertz in 1976, the economist Albert O Hirschman playfully expressed the first law of the social sciences: “Whenever a phenomenon in the social world is fully explained, it ceases to operate.” Perhaps the best historical example of this idea, or at least the most famous in the history of economic thought, was the publication of An Essay on the Principle of Population by Thomas Malthus in 1798.