In 1900 the world’s population numbered 1.65bn. A century later that figure had quadrupled to more than 6bn. At the same time, despite this unprecedented crowding of humanity, gross domestic product per capita rose in real terms by more than four times. That huge increase in productive potential redefined the lives of billions of people. It also enabled more destructive wars than ever before and, beyond wars, something even more terrifying: the real possibility of the total annihilation of human life on the planet. This duality of production and destruction gives the 20th century a claim to be the most radical in the history of our species.
1900年，世界人口數量為16.5億。一個世紀后，這一數字翻了兩番，超過了60億。與此同時，盡管人口數量空前密集，但人均國內生產總值實際增長了四倍多。生產潛力的巨大增長重新定義了數十億人的生活，也使得比以往任何時候都更具破壞性的戰爭成為可能，而在戰爭之外，還有更可怕的事情：地球上的人類生命被徹底消滅的真實可能性。這種生產和破壞的雙重性使20世紀有理由成為我們人類歷史上最激進的時期。