David Leonhardt interviews Charles Kenny, author of Getting Better. Kenny discusses Parson Malthus, who argued incorrectly that "each country’s output was pretty much limited by the amount of land available":

In Malthus’s time, output worldwide was indeed pretty much static for most of history, global G.D.P. had expanded by much less than half a percent a year. But since then, output has exploded everywhere. Between 1960 and 2000, only one country worldwide -– the Democratic Republic of the Congo saw G.D.P. growth slower than 0.5 percent per year, and only 11 countries saw output grow at less than 2 percent a year.

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