Despite its prominence in Malthus’s and Cook’s work, social scientists interested in long-term economic history regularly ignore the food/nonfood calories distinction and, focusing solely on food, conclude that between the invention of agriculture more than ten thousand years ago and the industrial revolution two hundred years ago not very much happened. In one of the most widely cited recent discussions, the economic historian Gregory Clark explicitly suggested that “the average person in the world of 1800 [CE] was no better off than the average person of 100,000 BC.”

But this is mistaken. As Malthus recognized, if good weather or advances in technology or organization raised food output, population did tend to expand to consume the surplus, forcing people to consume fewer and cheaper food calories; but despite the downward pressure on per capita food supply, increases in nonfood energy capture have, in the long run, steadily accumulated throughout Holocene times.

Ian Morris, The Measure of Civilization