中国和世界的人口下降：人越少，问题就越少？ - 纽约时报双语版

One statistic that stopped me recently is that China’s population is projected by some experts to halve by the end of the century. Halve! China was the most populous country in the world until only three years ago. Birthrates in Italy, Germany and Japan have been low for as long as I can remember. They’re now falling across the world.

最近有一个统计数据引起了我的注意：一些专家预测，到本世纪末，中国人口可能会减少一半。一半！就在三年前，中国还是世界上人口最多的国家。意大利、德国和日本的低出生率问题在我印象中已存在多年，而现在这种下降趋势正在全球蔓延。

So what does it mean for humanity when humanity is shrinking? Will it solve climate change by reducing the human footprint? Reduce the disruption of artificial intelligence taking human jobs? My colleague Amanda Taub, who writes The Interpreter newsletter, has done a lot of reporting on the disruptive power of demographic change. Her assessment is sobering.

那么，人口数量减少对人类意味着什么？人口下降带来的人类活动规模缩小是否会解决气候变化？能否减缓人工智能取代人类工作造成的冲击？我的同事、撰写“解析”通讯的阿曼达·陶布做了很多关于人口变化颠覆性力量的报道。她的评估发人深省。

Fewer people, fewer problems?

人口减少，问题就会减少吗？

by Amanda Taub

作者：阿曼达·陶布

The world’s birthrates are plunging.

全球的出生率正在急剧下滑。

China’s government revealed last month that its birthrate had plummeted to the lowest level on record since 1949. The U.S. said its population had grown at one of its slowest rates ever, caused in part by an immigration slowdown but also by a decades-long decline in fertility rates. Similar trends can be found around the globe, including in India, South Korea, Italy, Colombia and Mexico.

中国政府上个月披露，中国的出生率已降至1949年有记录以来的最低水平。美国表示，其人口增速处于历史上最慢的水平之一，这既与移民放缓有关，也与持续数十年的生育率下降有关。包括印度、韩国、意大利、哥伦比亚和墨西哥在内的全球多国都出现了类似趋势。

All this means the global population is on track to start shrinking in the next 50 to 60 years. That has enormous negative implications for the world’s economic productivity, innovation capacity and political stability.

这一切意味着，全球人口将在未来50到60年内开始萎缩。这对世界的经济生产力、创新能力和政治稳定都将产生巨大的负面影响。

Some optimists say a smaller human population might have some upsides. It could, they say, buffer the consequences of the two other world-remaking shifts that humanity is confronting: climate change and the potentially wrenching disruptions of A.I.

一些乐观主义者认为，人口减少可能带来一些好处。他们说，这或许能缓冲人类面临的另外两大重塑世界的巨变——气候变化和人工智能可能带来的剧烈冲击——所产生的影响。

These arguments have a certain logic. After all, climate change is the result of human emissions — wouldn’t fewer humans mean less strain on the planet? And amid fears that A.I. will displace human workers, couldn’t a smaller work force take the sting out of the prospective economic disruption?

这些说法背后似乎不无道理。毕竟，气候变化是人类排放的结果——人口变少了，对地球的压力不就小了吗？在人们担忧人工智能将取代人类工作之际，劳动力规模的缩小不是能缓解潜在的经济冲击吗？

If only. In fact, experts say, population decline is unlikely to be a solution to either problem — and may actually make them harder to solve.

但如果真是这样就好了。事实上，专家们指出，人口下降不太可能成为这两个问题的解决方案——反而可能让问题变得更加棘手。

‘A big, slow ship’

“一艘行动迟缓的大船”

Decades ago, many within the environmental movement called for a smaller population as a means of curbing carbon emissions and lessening the effects of climate change. Most climate experts are now focused on other solutions, but the arguments have had a lingering cultural impact: Whenever I write about the negative effects of falling fertility rates around the world, I hear from many readers who are certain that the emission-reduction benefits will outweigh the other costs of a smaller population.

几十年前，环保运动中的许多人曾呼吁缩减人口规模，把它视为遏制碳排放、减轻气候变化影响的一种手段。如今，大多数气候专家已将注意力转向其他解决方案，但这些论调却留下了深远的文化影响：每当我撰写全球生育率下降带来的负面影响时，总会收到许多读者的反馈，他们坚信减排效益将远超人口缩减带来的其他代价。

But when a team of researchers at the University of Texas at Austin and Hunter College in New York ran the numbers, they found that population decline was likely to have only a negligible impact on climate change.

然而，得克萨斯大学奥斯汀分校与纽约亨特学院的一组研究人员进行测算后发现，人口下降对气候变化的影响很可能微乎其微。

The reason? The timelines just don’t match up. Because human life spans are long, the researchers wrote in a recent working paper, falling birthrates will take a long time to meaningfully change the size of the world’s population. The threat of climate change is much more immediate — today’s emissions will have a lasting effect on the Earth’s atmosphere.

原因何在？关键在于时机不匹配。研究人员在近期的一篇工作底稿中指出，由于人类寿命较长，生育率下降需要很长时间才能显著改变全球人口规模。而气候变化的威胁却迫在眉睫——当下的排放将对地球大气产生持久影响。

Solutions to climate change, which would also have the effect of reducing per-person emissions, need to happen within a much shorter period. By the time the population actually does shrink, having fewer people won’t make much difference.

应对气候变化的解决方案——这些方案同时也能降低人均排放——必须在更短的时间内实施。等到人口真的开始减少时，人口变少本身已难以产生显著影响。

“The population is a big ship, slow to turn,” said Dean Spears, one of the researchers who worked on the paper.

“人口就像一艘大船，转向极其缓慢，”参与该论文的研究者迪恩·斯皮尔斯如此形容。

The researchers analyzed a few different models of population size and emissions changes. They found that if the world’s population was to shrink by billions of people by the year 2200, which will happen if things stay on their current trajectory, it would make less than one-tenth of a degree Celsius of difference to peak temperatures when compared with a population that remains stable over time.

研究人员分析了人口规模与排放变化的几个不同模型。他们发现，若按照当前趋势，到2200年全球人口减少数十亿，与人口长期保持稳定相比，对峰值气温的影响也不到摄氏0.1度。

The A.I. revolution

人工智能革命

Another frequent rejoinder to demographic doomsayers: We’ll just have robots do the work for us! Or, more bleakly: If A.I. is going to destroy all the jobs, won’t it maybe be better to have a smaller work force to start with?

对人口危言论者另一种常见的反驳是：我们可以让机器人替我们工作啊！或者更悲观地说：如果人工智能终将摧毁所有工作岗位，那从一开始就减少劳动力规模岂不是更好？

For now, it appears that the kind of robots we’d need to replace humans at scale won’t arrive soon enough to help compensate for the slowing productivity growth of an aging population, said Beata Javorcik, the chief economist of the European Bank for Reconstruction and Development. In many places, the problem of an aging population and shrinking work force is already here. Post-Communist countries in Eastern Europe, for example, “got old before getting rich,” Javorcik said.

欧洲复兴开发银行首席经济学家贝娅塔·亚沃尔奇克指出，目前看来，我们需要的那种能够大规模替代人类的机器人，其技术成熟速度远不足以弥补因人口老龄化导致的生产力增长放缓。在许多地方，人口老龄化和劳动力萎缩的问题已经存在。例如，东欧的一些后共产主义国家，“还没富起来，就已经老了”，亚沃尔奇克说。

As for the bleaker scenario, economists like David Autor at M.I.T. believe it’s unlikely that A.I. will replace all or most human workers. Historically, labor forces have adapted to even the most seismic of technological changes. That might well happen with A.I., in which case a shrinking pool of workers would still dampen growth when the A.I.-driven productivity surge eventually did arrive.

至于那种更悲观的设想，麻省理工学院的经济学家戴维·奥托等学者认为，人工智能不太可能完全取代或大部分取代人类劳动力。历史上，劳动力市场即使面对最剧烈的技术变革也能逐步适应。人工智能很可能也会如此。在这种情况下，即使未来出现人工智能驱动的生产力激增，劳动力池的萎缩仍将抑制经济增长。

But if A.I. did replace humans, Autor said, a smaller population would not be much of a cushion against the economic or political fallout. Even a small displaced work force has the potential to cause major disruption.

奥托进一步指出，即便人工智能真的取代了人类，人口减少也无法有效缓冲可能引发的经济或政治冲击。即便只是小部分劳动力遭到取代，也足以引发严重的社会动荡。

In other words, there is no magic bullet (A.I.) for the coming population collapse, and the collapse itself will not be a magic bullet (for climate change). There is only the slow, painstaking work of making policy that will be able to accommodate a new reality.

换句话说，面对即将到来的人口塌缩，人工智能并非灵丹妙药，而人口塌缩本身也不会成为应对气候变化的解药。唯一可行的，只有通过缓慢而艰辛的政策制定过程，来适应这个正在成型的新现实。

本文节译自时报全球新闻电邮The World。

翻译：杜然

查看原文：中国和世界的人口下降：人越少，问题就越少？ - 纽约时报双语版