The lack of recognition was unmerited; Hong apparently captured the workings of the Malthusian trap better than Malthus. (I use the hedge word “apparently” because he never worked out the details.) The Englishman’s theory made a simple prediction: more food would lead to more mouths would lead to more misery. In fact, though, the world’s farmers have more than kept pace. Between 1961 and 2007 humankind’s numbers doubled, roughly speaking, while global harvests of wheat, rice and maize tripled. As population has soared, in fact, the percentage of chronically malnourished has fallen — contrary to Malthus’s prediction. Hunger still exists, to be sure, but the chance that any given child will be malnourished has steadily, hearteningly declined. Hong, by contrast, pointed to a related but more complex prospect. The continual need to increase yields, Hong presciently suggested, would lead to an ecological catastrophe, which could cause social dysfunction — and with it massive human suffering.
Exactly this process is what researchers mean today when they talk about the Malthusian trap. Indeed, one way to summarize today’s environmental disputes is to say that almost all boil down to the question of whether humankind will continue to accumulate wealth and knowledge, as has been the case since the Industrial Revolution, or whether the environmental impacts of that accumulation — soil degradation, loss of biodiversity, consumption of groundwater supplies, climate change — will snap shut the jaws of the Malthusian trap, returning the earth to pre-industrial wretchedness.