Three hours a day is quite enough,” wrote John Maynard Keynes in his 1930 essay Economic Possibilities for our Grandchildren. The essay continues to tantalise its readers today, thanks in part to a forecast that is looking magnificently right — that in advanced economies people could be up to eight times better off in 2030 than in 1930 — coupled with a forecast that is looking spectacularly wrong, that we would be working 15-hour weeks.

约翰•梅纳德•凯恩斯(John Maynard Keynes)曾在1930年的一篇短文《我们子孙后代的经济可能性》(Economic Possibilities for our Grandchildren)中写道：“每天3小时就足够了。”这篇短文现在仍吸引着读者，部分原因是一项看上去极其正确的预测：到2030年，发达经济体国民的富裕程度可能会达到1930年的8倍，还有一项看上去极其错误的预测：我们将每周工作15小时。

In 2008, economists Lorenzo Pecchi and Gustavo Piga edited a book in which celebrated economists pondered Keynes’s essay. One contributor, Benjamin Friedman of Harvard University, has recently revisited the question of what Keynes got wrong, and produced a thought-provoking answer.

2008年，经济学家洛伦佐•佩基(Lorenzo Pecchi)和古斯塔沃•皮加(Gustavo Piga)编辑了一本书，在书中，一些知名经济学家对凯恩斯的这篇短文进行了探讨。撰稿人之一、哈佛大学(Harvard University)教授本杰明•弗里德曼(Benjamin Friedman)最近重新提到了凯恩斯预测错的那个问题，并提出了一个发人深省的答案。

First, it is worth teasing out the nature and extent of Keynes’s error. He was right to predict that we would be working less. We enter the workforce later, after long and not-always-arduous courses of study. We enjoy longer retirements. The work week itself is getting shorter. In non-agricultural employment in the US, the week was 69 hours in 1830 — the equivalent of working 11 hours a day but only three hours on Sundays. By 1930, a full-time work week was 47 hours; each decade, American workers were working two hours less every week.

首先，我们有必要探究一下凯恩斯错误的性质和程度。他预测我们的工作时间将变少，这是对的。如今的人们在经过漫长（且不总是勤奋）的学习后才进入职场。我们享受着更长的退休阶段。每周工作时间在缩短。1830年，在美国非农业部门，人们每周工作69小时，相当于每天工作11个小时，只是周日工作3小时。到1930年，全职员工的每周工作时间为47小时；每10年，美国劳动者每周的工作时间会减少两小时。

But Keynes overestimated how rapidly and for how long that trend would continue. By 1970 the work week was down to 39 hours. If the work week had continued to shrink, we would be working 30-hour weeks by now, and perhaps 25-hour weeks by 2030. But by around 1970, the slacking-off stopped. Why?

但凯恩斯高估了这一趋势持续的速度和时间。到1970年，每周工作时间降至39小时。如果每周工作时间继续减少的话，我们现在的每周工作时间将达到30个小时，到2030年将达到25个小时。但是，到了1970年前后，这种缩减趋势停止了。为什么呢？

One natural response is that people are never satisfied: perhaps their desire to consume can be inflamed by advertisers; perhaps it is just that one must always have a better car, a sharper suit, and a more tasteful kitchen than the neighbours. Since the neighbours are also getting richer, nothing about this process allows anyone to take time off.

一个自然的回应是人们永远不会感到满足：或许广告商们燃起了他们的消费欲望；或许只是因为人们永远希望拥有比邻居更好的车、更抢眼的西装以及更有品位的厨房。由于邻居们也在变得更富有，因此这个过程不允许任何人休息。

No doubt there is much in this. But Friedman takes a different angle. Rather than asking how Keynes could have been so right about income but so wrong about leisure, Friedman points out that Keynes might not have been quite so on the mark about income as we usually assume. For while the US economy grew briskly until the crisis of 2007, median household incomes started stagnating long before then — around 1970, in fact.

确实，这很有道理。但弗里德曼有着不同的视角。他没有问凯恩斯为何猜对了收入却猜错了人们的休闲时间，而是指出，凯恩斯对于收入的看法可能不像我们通常认为的那样正确。尽管在2007年金融危机之前，美国经济增长不俗，但家庭收入中值早在那之前就开始停滞了，实际上是在1970年前后。

The gap between the growth of the economy and the growth of median household incomes is explained by a patchwork of factors, including a change in the nature of households themselves, with more income being diverted to healthcare costs, and an increasing share of income accruing to the highest earners. In short, perhaps progress towards the 15-hour work week has stalled because the typical US household’s income has stalled too. Household incomes started to stagnate at the same time as the work week stopped shrinking.

一些形形色色的因素可以解释经济增速与家庭收入中值增速之间的差距，包括家庭本身性质的变化，更多收入转向医疗成本，收入最高者在总收入中所占份额越来越高。简言之，朝着每周15小时工作制发展的过程之所以停滞，或许是因为美国典型家庭的收入也陷入停滞。家庭收入开始停滞的同时，每周工作时间停止缩短。

This idea makes good sense but it does not explain what is happening to higher earners. Since their incomes have not stagnated — far from it — one might expect them to be taking some of the benefits of very high hourly earnings in the form of shorter days and longer weekends. Not so. According to research published by economists Mark Aguiar and Erik Hurst in 2006 — a nice snapshot of life before the great recession — higher earners were enjoying less leisure.

这种看法很有道理，但它没有解释收入较高者的行为是怎么回事。既然他们的收入并没有停滞（远非如此），因此人们可能会预测，他们会以减少工作时间和延长周末的形式，享受高薪所带来的实惠。实情并非如此。根据经济学家马克•阿吉亚尔(Mark Aguiar)和埃里克•赫斯特(Erik Hurst) 2006年发表的一项研究，收入更高者享受的空闲时间减少。该研究是对“大衰退”之前生活的精彩“快照”。

So the puzzle has taken a different shape. Ordinary people have been enjoying some measure of both the income gains and the leisure gains that Keynes predicted — but rather less of both than we might have hoped.

因此，这个难解之谜呈现出了不同的形态。普通人像凯恩斯预测的那样享受着收入增长和空闲时间增加这两方面的好处，但程度都不及我们的预期。

The economic elites, meanwhile, continue to embody a paradox: all the income gains that Keynes expected and more, but limited leisure.

与此同时，经济精英们继续体现出一个悖论：实现凯恩斯预测的全部收入增长、但空闲时间更有限。

The likely reason for that is that, in many careers, it’s hard to break through to the top echelons without putting in long hours. It is not easy to make it to the C-suite on a 20-hour week, no matter how talented one is. And because the income distribution is highly skewed, the stakes are high: working 70 hours a week like it’s 1830 all over again may put you on track for a six-figure bonus, while working 35 hours a week may put you on track for the scrapheap.

可能的原因是，在很多职业中，我们很难在不投入长时间工作的情况下升至企业高层。你很难通过每周工作20小时就进入公司管理层，不管你有多么优秀。由于收入分配高度倾斜，这方面的选择事关重大：每周工作70小时（就像又回到1830年）可能会让你有望赚到6位数年薪，而每周工作35小时，可能会让你沦为没出息的人。

The consequences of all this can emerge in unexpected places. As a recent research paper by economists Lena Edlund, Cecilia Machado and Maria Micaela Sviatschi points out, urban centres in the US were undesirable places to live in the late 1970s and early 1980s. People paid a premium to live in the suburbs and commuted in to the city centres to work. The situation is now reversed. Why? The answer, suggest Edlund and her colleagues, is that affluent people don’t have time to commute any more. They’ll pay more for cramped city-centre apartments if by doing so they can save time.

这一切的后果可能出现在意想不到的地方。正如经济学家莱纳•埃德隆德(Lena Edlund)、塞西莉•马沙多(Cecilia Machado)和玛丽亚•米凯拉•斯维亚特奇(Maria Micaela Sviatschi)最近所著的一篇研究论文所指出的那样，上世纪70年代末和80年代初，美国城市中心成为不适宜居住的地方。人们花高价住在郊区，每天通勤来到城市中心上班。如今情况已逆转。为什么？埃德隆德和她的同事们认为，答案是富人不再有时间通勤了。如果他们可以省下时间的话，他们宁愿付出更高价格，住在相对狭小的市中心公寓里。

If there is a limited supply of city-centre apartments, and your affluent colleagues are snapping them up, what on earth can you do? Work harder. Homes such as Keynes’s elegant town house in Bloomsbury now cost millions of pounds. Three hours a day is not remotely enough.

如果市中心公寓的供应有限，而你的富裕同事们在竞相抢购的话，你到底能做什么？更努力地工作吧。像凯恩斯位于布卢姆斯伯里的优雅别墅那样的房子现在要几百万英镑。每天工作3小时是绝对不够的。