多年来，经济学的公认智慧几乎与佛教一样：金钱不会让你幸福。（例如，见英国《金融时报》中文版9月7日至14日的系列文章“幸福生活的七大秘诀”。）

    不过，我或许应该修改一下自己的说法。研究该主题的经济学家往往相信，只要超出某个最低限度，绝对收入对幸福就几乎没有影响。在任何指定的社会，富人往往比穷人更幸福，但富国的居民并不明显比中等收入国家的居民更幸福，而且尽管我们的父母在我们这个年龄时没有我们富有，但我们并不比他们更幸福。

这个发现一直被称作伊斯特林悖论(Easterlin Paradox)——以上世纪70年代首次注意到该现象的经济学家理查德•伊斯特林(Richard Easterlin)的名字命名。对这个悖论的一个解释是：重要的是要赶超与自己地位相当的人。如果我们只关心自己在社会中的位置，伊斯特林从数据中发现的现象就容易解释了。

    但是最近的两篇研究报告却提出了不同的结论。2002年诺贝尔经济学奖得主、心理学家丹尼尔•卡纳曼(Daniel Kahneman)表示：“必须调整幸福的概念。”许多关于幸福的研究都聚焦于“生活满意度”——研究人员问人们是否总体上对生活感到满意。但卡纳曼研究的是情绪：人们是日渐感到满足、放松或欣喜，还是紧张、沮丧或失意？

    卡纳曼和安格斯•狄顿(Angus Deaton) 8月份在《国家自然科学院学报》(Proceedings of the National Academy of Sciences)上发表了一篇研究报告。通过研究50万美国人对每日调查的答复，他们对这两种幸福标准进行了考量，结果发现：生活满意度与金钱有关，但如果收入超过约7.5万美元，金钱就不会改善你的情绪。因此，伊斯特林正确与否取决于你对幸福的定义。

    沃顿商学院(Wharton School)三位经济学家——丹尼尔•萨克斯(Daniel Sacks)、贝齐•史蒂文森(Betsey Stevenson)和贾斯廷•沃尔弗斯(Justin Wolfers)——发表的最新研究报告，对有关生活满意度的调查进行了补充。与生活满意度有关的不只是金钱，但无论他们比较的是同一国家的两个人（一个比另一个富裕10%）；还是两个国家（一国人均收入比另一国高10%）的平均幸福感；抑或是一个国家经过一段时期的经济增长，富裕程度提高了10%以后，居民幸福感的增加程度，他们得出的结果都说明，生活满意度与金钱有关。对幸福而言，重要的是绝对收入，而非相对收入。这就又提出了生活在富人世界的吸引力的问题。

    贾斯廷•沃尔弗斯宣称，生活满意度与收入之间的关系是“你在社会科学跨国数据中所见到的关联度最高的数据之一”。如果是这样，那何以前并不明显？沃尔弗斯将问题归咎于较早的数据——例如，重新翻译了在日本所问的问题后就会明白，在经济繁荣时，生活满意度之所以会显得停滞不前，只是因为问的问题在不断变化。

但不是所有人都如此急于否定伊斯特林的研究——他的成果经受住了多年仔细审查的考验。英国华威大学(University of Warwick)的安德鲁•奥斯瓦尔德(Andrew Oswald)指出，沃顿商学院的研究可能没有成功地将收入与失业分开——人们早就知道，失业是最令人沮丧的经历之一。

    有一点似乎得到了所有人的认可：无论出于什么原因，美国人自身的生活满意度数十年来一直停滞不前。沃尔弗斯称：“这支持了伊斯特林的观点。”或许巴拉克•奥巴马(Barack Obama)一直在保持关注：三位幸福研究领域的主要学者——贝齐•史蒂文森、与卡纳曼合著研究报告的艾伦•克鲁尔格(Alan Krueger)和卡斯•桑斯坦(Cass Sunstein)——都在政府担任高级职位。或许他们能找到改善美国人情绪的方法。

For many years the received wisdom in economics has been much the same as that in Buddhism: money doesn’t make you happy (see, for instance, “The Seven Secrets of a Happy Life”, FT Weekend Magazine, August 28/29).

I should probably modify my statement though. Economists who study the subject have tended to believe that beyond some minimum, absolute income has little effect on happiness. In any given society, the rich tend to be happier than the poor, but citizens of rich countries are not notably happier than citizens of middle-income countries, and while we are richer than our parents were at our age, we are no happier.

This finding has been called the Easterlin Paradox, after Richard Easterlin, the economist who first observed it back in the 1970s. The paradox has an explanation: what matters is keeping up with the Joneses. If we care only about our place in society, the pattern Easterlin discovered in the data is readily explained.

But two recent pieces of research suggest a different conclusion. “The concept of happiness has to be reorganised,” says Daniel Kahneman, a psychologist who won the Nobel memorial prize in economics in 2002. Much happiness research focuses on “life satisfaction”, where researchers ask people whether they’re satisfied with life as a whole. But Kahneman studies mood: do people, moment by moment, feel content, relaxed or joyful – or stressed, depressed or frustrated?

Kahneman and Angus Deaton, in research published in August in the Proceedings of the National Academy of Sciences, looked at these two measures of happiness in half a million responses to a daily survey of Americans. They found that money is correlated with life satisfaction, but beyond an income of about $75,000, it doesn’t improve your mood: so whether or not Easterlin is right depends on what you mean by happiness.

A new working paper released by three Wharton School economists, Daniel Sacks, Betsey Stevenson and Justin Wolfers, amplifies the finding on life satisfaction. Not only is money correlated with life satisfaction, but this is true whether they compare the happiness of two people in the same country, one 10 per cent richer than another; or the average happiness in two countries, one with 10 per cent higher income per capita; or the increase in happiness after a period of economic growth has made a single country 10 per cent richer than it used to be. It is absolute income, not relative income, which matters for happiness. The attractions of living in a rich man’s world are back on the table.

Justin Wolfers claims that the relationship between life satisfaction and income is “one of the highest correlations you’ll ever see in a cross-country data set in the social sciences, ever.” If so, why has this not been clear before? Wolfers blames problems with the older data – for instance, it became apparent, after retranslating the questions asked in Japan, that life satisfaction seemed to stagnate as the economy boomed only because the questions kept changing.

But not everyone is so quick to dismiss Easterlin’s work, which has survived careful scrutiny over the years. Andrew Oswald of Warwick University points out that the Wharton research may not have successfully disentangled income from unemployment, which has long been known to be one of the most depressing of experiences.

And everyone seems to agree on one thing: for whatever reason, life satisfaction in America itself has been stagnating for decades. “Score that one for Easterlin,” says Justin Wolfers. Perhaps Barack Obama has been taking note: three leading happiness scholars, Betsey Stevenson, Kahneman’s co-author Alan Krueger and Cass Sunstein all have senior government positions. Maybe they can figure out how to improve the nation’s mood.