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，世界人口数量为16.5亿。一个世纪后，这一数字翻了两番，超过了60亿。与此同时，尽管人口数量空前密集，但人均国内生产总值实际增长了四倍多。生产潜力的巨大增长重新定义了数十亿人的生活，也使得比以往任何时候都更具破坏性的战争成为可能，而在战争之外，还有更可怕的事情：地球上的人类生命被彻底消灭的真实可能性。这种生产和破坏的双重性使20世纪有理由成为我们人类历史上最激进的时期。