The limit of 80 billion would never be reached, because nobody would want to live in such a jam-packed country. But thinking in these terms was clarifying, Weaver thought. It showed that viewing the human dilemma in terms of an ecological carrying capacity was a mistake. The planet’s actual, physical carrying capacity was so large—scores of billions of people—as to be irrelevant. The true problem was not that humankind risked surpassing natural limits, but that our species didn’t know how to tap more than a fraction of the energy provided by nature.
