Economics focus
经济聚焦
Paul Samuelson
保罗.萨缪尔森

Dec 17th 2009
From The Economist print edition

The last of the great general economists died on December 13th, aged 94
12月13日，最后一位经济学通才去世，享年94岁

“I WAS reborn, born as an economist, at 8.00am on January 2nd 1932, in the University of Chicago classroom,” wrote Paul Samuelson in a memoir published earlier this month. He became probably the most influential economist of the second half of the 20th century. For his work in several branches of the dismal science he became the first American economics Nobel laureate. Through his bestselling textbook, he introduced millions of people to the subject. And right to the end he kept on mentoring the profession’s brightest stars.
“1932年1月2日，在芝加哥大学的讲堂中，我得到了第二次生命——作为经济学家重生了。”本月早些时候出版的保罗.萨缪尔森回忆录中，他如是写道。他或许是20世纪下半叶最具影响的经济学家。沉闷如经济学，他在该领域数分支都有著作于世，并因此成为第一位荣膺诺贝尔奖的美国经济学家。在自己的畅销课本中，他向千百万人介绍了这门学科。直至生命垂暮，萨缪尔森仍在谆谆教诲着经济领域中最闪亮的学者。

His actual birth took place almost 17 years earlier in the steel town of Gary, Indiana, to a family of upwardly mobile Polish immigrants. His earliest memories—of the recession of 1919-21 and strikebreaking immigrant workers from Mexico, and of the boom and bust that followed—shaped Mr Samuelson’s macroeconomic views throughout his life. He approved of massive government spending to help an economy escape from recession when monetary policy can do no more. When the Obama administration introduced just that sort of stimulus this year, partly on the advice of Mr Samuelson’s nephew, Larry Summers, who is Mr Obama’s chief economic adviser, he was quick to approve.
其实，萨缪尔森在此17年前生于印第安纳州“钢都”加里市的一个波兰移民家庭中，当时正值家族兴旺。他儿时经历1919-21年经济衰退和墨西哥民工罢工，以及随后的繁荣萧条更迭，而这些早期的记忆对他的宏观经济理论产生了毕生影响。他同意如货币政策力不能及，政府应大幅出资避免经济萧条。今年奥巴马政府引入上述经济刺激，其首席经济顾问，萨缪尔森的侄子拉里.萨默斯谏言有功，而萨缪尔森毫不含糊，双手赞成。

Though regarded as America’s leading standard-bearer for Keynesian economics, he called himself a “cafeteria Keynesian”, just picking the bits he liked. His combination of Keynesian and classical economic ideas became known as the “neoclassical synthesis”. From his chair at the Massachusetts Institute of Technology and in his column in Newsweek, the self-described “dull centrist” became a fierce critic of the libertarian Chicago School, and especially of Milton Friedman (writer of a rival Newsweek column). Markets are not perfect, he believed, and dire warnings from Friedman, and earlier from Friedrich von Hayek, about the regulation of markets “tells us something about them rather than something about Genghis Khan or Franklin Roosevelt. It is paranoid to warn against inevitable slippery slopes…once individual commercial freedoms are in any way infringed upon.”
纵使萨缪尔森被推崇为凯恩斯经济理论的倡导先锋，却自称“自助餐厅凯恩斯主义者”，发扬理论全凭爱好。他综合凯恩斯和古典经济思想成就“新古典综合”，传扬于世。在麻省理工大学的讲台上，在《新闻周刊》的专栏中，他自诩“沉闷中间派”却激烈批判倡导自由主义的芝加哥学派，尤其是同为《新闻周刊》专栏写手的弥尔顿.弗雷德曼。他认为市场并不完美，而弗雷德曼——以及从前弗雷德里希.冯.海因克——的耸人听闻“只能揭示他们心底的脆弱，而看不到一丝一毫成吉思汗和罗斯福的身影。下坡路不可避免……看到个体商业自由受到侵犯就发出防范警告，纯属偏执抓狂。”

As for Mr Samuelson’s friend of 50 years, Alan Greenspan, once chairman of the Federal Reserve, “the trouble is that he had been an Ayn Rander”—a devotee of laissez-faire capitalism. “You can take the boy out of the cult but you can’t take the cult out of the boy,” Mr Samuelson told the Atlantic this summer. “He actually had [an] instruction, probably pinned on the wall: ‘Nothing from this office should go forth which discredits the capitalist system. Greed is good’.”
萨缪尔森曾经评价自己五十年老友——美联储前主席艾伦.格林斯潘：“他就是曾经追随艾茵.兰德，才不慎失足。”艾茵.兰德是放任资本主义的忠实拥趸。“改邪归正易，浪子回头难呐。”萨缪尔森今年夏天接受《大西洋月刊》采访时说，“他还真有个座右铭，还钉在了办公室墙上，写着：‘轻渎资本主义，一律不准出门。人皆贪婪，此乃常情。’”

The huge sales of Mr Samuelson’s textbook, “Economics”, first published in 1948 and updated every three years, owed much to his lively writing. (The abstract of his recent memoir ended with the words: “Boo hoo.”) The book transformed how economics was—and is—taught around the world. If the earlier editions too readily believed that an economy could achieve equilibrium, that may have stemmed from the author’s conviction that mathematics could be a useful tool for economists, and that economics had much to learn from physics and the laws of thermodynamics. Today it is fashionable to argue that economics was led astray by “physics envy”, which blinded it to the subtleties of human behaviour, yet after winning his Nobel prize in 1970 Mr Samuelson anticipated economists’ current interest in biological systems by writing several papers on Mendelian dynamics.
1948年，萨缪尔森的课本《经济学》首次出版，此后每三年就进行一次修订，其销量之大，盖因老人家笔调鲜活。（他最近出版的回忆录摘要中，便以“呜呼”二字结尾。）《经济学》一书颠覆了经济教学，并对其产生了持久影响。如果说早期版次过于相信经济可以达到均衡，那大概是因为作者坚信数学可以成为经济学家的有效工具，经济学可汲物理和热力学定律之长。今天，许多人认为经济学因“物理嫉妒”才会忽视人类细微行为，从而误入歧途；而1970年赢得诺贝尔奖之后，萨缪尔森就孟德尔动量撰写数篇论文，成功预见了今日经济学家对生物系统的盎然兴趣。

The inefficient market
低效市场

He was the last of the great general economists, making important contributions on trade, macroeconomics, public finance and consumer behaviour. Yet he decided, at around 50, that to remain academically competitive he had to specialise. Perhaps because it was close to his beloved mathematics, the specialist field he chose was financial economics.
他是经济领域最后一位通才，在贸易、宏观经济、财政和消费行为领域均有建树。年近半百，萨老却决定为保持学术竞争力，他必须专攻。他选择了金融经济，大概因为这同他挚爱的数学密不可分。

His work helped lay the foundations for two of the field’s biggest ideas: the efficient-market hypothesis and options pricing. In 1965 he published a paper explaining that in well-informed and competitive speculative markets, price movements over time will be essentially random—a concept at the heart of the efficient-market hypothesis later described in its full majesty by Eugene Fama, whom Mr Samuelson believed ought to win a Nobel prize. In the 1950s it was Mr Samuelson who had rediscovered the pioneering early work of Louis Bachelier, a French mathematician whose insights would later underpin the Black-Scholes option-pricing model; and it was Mr Samuelson who suggested the assumption, that share prices move according to geometric Brownian motion, which makes this model workable. Mr Samuelson remained close to Robert Merton, who won a Nobel for his work with Fischer Black and Myron Scholes on options pricing.
萨缪尔森的著作奠定了有效市场假说和期权定价这两大经济学观念的基础。1965年，萨老发表论文，解释在消息灵通而具竞争力的投机市场中，只要假以时日，价格变动就会出现随机倾向——这是有效市场假说的核心概念；此后，萨老认为应为诺贝尔奖获得者的尤金.法玛对此概念进行了雄辩阐述。20世纪50年代，是萨老掸去法国数学家路易.巴舍利耶的先锋性早期著作尘封，成就了布莱克-斯科尔斯期权定价模型；同样，萨老提出股票价格遵循几何布朗运动假说，这一期权定价模型才得以运转。长期以来，萨缪尔森同罗伯特.默顿常有往来，而费希尔.布莱克和迈伦.斯科尔斯所创这一模型，又助默顿戴上诺贝尔桂冠。

Yet Mr Samuelson also understood that beyond the ivory tower the conditions necessary for efficient markets rarely existed; they needed regulating. “To understand economics you need to know not only fundamentals but also its nuances,” Mr Samuelson would explain. “When someone preaches ‘Economics in one lesson’ I advise: Go back for the second lesson.” The latest crisis (for which he felt some responsibility, since he had helped develop financial derivatives that company executives did not understand) proved that “free markets do not stabilise themselves. Zero regulating is vastly suboptimal to rational regulating. Libertarianism is its own worst enemy!”
然而，萨缪尔森同样清楚，走下象牙塔，有效市场的必要条件鲜有存在；市场需要规范。“要理解经济学，不能只明白其中的基本原则，还要理解里面的细微差别。”萨缪尔森解释道，“有人说什么‘一课经济学’，我看，给我回去再上一课吧。”萨老认为自己对眼下的金融危机责任不可推卸，因为他曾经也帮助创造公司高管无法理解的金融衍生品。而这次金融危机也证明“自由市场不能自我调控。零监管远远不如合理调控。自由主义最大的敌人，正是自己！”

Mr Samuelson was happy to be “linked with such Methuselah masters as Verdi” who did some of their best work in old age. He was able to do so, not least, because of his interest in evidence-based medicine. For decades he read the New England Journal of Medicine, and—noting a weakness in his male ancestors—he was an early adopter of cholesterol-reducing statin pills, as well as skimmed milk. His passion for “looking for theoretical understandings of empirical reality” may help explain his long life, as well as his lengthy list of achievements.
萨缪尔森称，能与老年有成的“玛土撒拉大师威尔第比肩”，荣幸至极。他晚年多产，是因为对循证药物学颇感兴趣。几十年来，他一直阅读《新英格兰医学杂志》，并且因家族遗传之故，降胆固醇药他汀类药物推出初期就予以支持。对于脱脂乳，他也推崇备至。萨老热衷“在经验事实中寻求理论理解”，故而长寿，故而才能著作等身。