“Take any variable of human well-being—longevity, nutrition, income, mortality, overall population—and draw a graph of its value over time,” Charles Mann writes in The Wizard and the Prophet. “In almost every case it skitters along at a low level for thousands of years, then rises abruptly in the eighteenth and nineteenth centuries, as humans learn to wield the trapped solar power in coal, oil and natural gas.”10 Without energy, even material splendor has sharp limits.
