又见约翰 ·纳什
天才巨匠的 “朴素"哲学
。 本刊记者 郭子初
当201 1年诺奖北京论坛开幕式宣布结束时,主席
台上就座的诺奖得主纷纷离席,只有一位老人仍旧静
静地坐在那里。少时,他缓缓地左右看了一下 ,这才
收拾物品起身离场,然而没走几步就被媒体记者以及
现场听会人士围得水泄不通。这位行动有些迟缓的老
人就是 “博弈论”大师、天才数学家约翰 ·纳什。此
次论坛期间最耀眼瞩目、请求签名 以及合影 留念最多
的 “明星”非他莫属。
论坛期间,会议主持人依旧还会提到那部大家熟
知的名叫 美丽心灵 的电影。这 时你会不得不佩服
艺术的传播力量。因为每有人问起 “谁是约翰 -纳什”
时,人们多数不会向他讲解 “纳什均衡”或者博弈论,
而会说他就是当年那部独揽4项奥斯卡大奖的电影 美
丽心灵))的真实原型。而纳什本人对这部电影的制作
以及艺术成就的评价则相当高 ,他坦言 自己看过好几
遍,不过 ,每次看的时候,心里并不好受。“我认为这
部电影有助于人们理解与尊重患有精神疾病的人。”
纳什在 2O几岁时就做出惊人的数学发现,在经济
学博弈论中享有国际声誉 ;3O岁时,罹患妄想型精神
分裂症 ,在天才与狂乱中历经痛苦,在长达 30年的过程
中始终无法进行正常的研究工作 ,一直备受严重的幻像、
幻听、思维和情绪混乱的困扰 ,意志力被完全摧毁。他
放弃了数学,沉醉于命理学和宗教预言,多次逃往欧洲,
6次被送进精神病院⋯⋯
或许是 电影以及纳什本人的经历给记者带来先入为
主的忧伤情绪,我们甚至不太愿意再打扰这位已经 83岁
高龄并且历经磨难的老人。说来纳什与本刊颇有渊源。他
曾在 6年前,也就是 2005年 7月接受本刊记者独家专访
并应邀登上 中国金融家 封面。6年后再见,纳什似乎
沉默了许多。在开幕式结束的二十分钟里,看着他如
贵族般端然的神色、纯净清澈的眼神,静静地坐在那
里为每~位崇拜者签名,我们心中更多的被一种莫名
的情感触动着,甚至忘记了此番参会的职业使命。
在之后进行的演讲环节,纳什开门见山,似乎除
了数学与经济学外,连句应景的话也不愿多说。老人
高挑瘦弱、彬彬有礼。演讲时他坚持站着讲了近一个
小时,主题则是他思考已久的关于理想货币的话题。
纳什显然作了充分准备,制作了PPT,但基本以文字
为主。不知是出于严谨还是其他原因,他手拿话筒逐
2011年第10期中围桃 寄I
行逐段地念,声音低沉,语速缓慢。有趣的是,纳什
每每发言总在规定时间内讲完,互动环节回答问题言
简意赅,举手投足问流露着普通人朴素的处事方式和
态度。
当有参会人士问道,在当前世界经济前景黯淡的
形势下,美国应采取何种措施推动本国经济增长时,
纳什表示,美国的经济问题积重难返,就像一个患有
多种疾病的病人,没有一种立竿见影的特效药能帮助
它摆脱困境。在他看来,量化宽松政策会造成美元贬
值,带来通货膨胀问题。但在经济学界,一直有一种
观点认为通货膨胀会带来一定的好处。“在我所在的
普林斯顿大学,有学者认为日本在多年前采取大规模
让 日元贬值的措施来刺激经济增长,取得了一定成效。
但我不赞同这种观点,这种做法有其脆弱性。”
关于中国购买美国债券是否安全的问题,纳什
的回答简单却颇有哲理 :“购买任何国家的债券都是
一 场赌局,因为这些债券只是一些纸制票据。任何购
买者都必须小心谨慎。其中除考虑经济因素外,政治
因素也是一个重要原 因。”虽然纳什没有直接给出答
案,不过他的回答倒让人想起了他的 “博弈论”理论,
即在一场赌局中,斗争各方是否存在着最合理的行为
方案。
中国是否有必要出手救欧洲 ,如帮助意大利走出
危机是近期学术界探讨的热点话题。纳什对此表示 :
“很多人都认为,如果 中国出手救意大利,很有可能
在未来意大利股指上扬的时候,能够有所斩获。前两
天我们看到股市似乎又上涨了一点,但总体来说 ,人
们还是存在一些顾虑。”
前不久乔治 ·索罗斯表示 ,目前的危机比 2008
年更糟。欧元区的主要债务问题,可能会导致全球经
济体面临财政和信贷紧缩。目前的危机之所以严重 ,
是因为没有一个适当的机构、一种机制来解决欧元区
的债务问题。
当被问及如何看待索罗斯的观点,纳什这样坦诚
说道 :“我之前在普林斯顿大学的一次经济学会议上
曾经见到过索罗斯先生 ,他是一个非常聪明的人,但
我并不知道他的观点是否正确,因为这就像天气预报
一 样难以预测,而经济危机不能仅仅依据人们的观点
来决定。如果是单纯的恐慌,可能不会产生大的问题,
只有 当大范围的企业出现股价下跌的时候 ,才能够产
54 I aA T
生效应。”
欧美债务危机恶化 ,主要西方大国政府似乎都陷入
了进退维谷的困境,能有化解危机的更好办法吗?当记者
期待着纳什给出几点建议时,纳什答案中的逻辑同样简单。
“有一句古话叫 ‘有志者事竟成’。如果这些国家的政府有
足够强烈的意愿,那么他们就能拿出解决危机的有效办法。
因为有了坚定的意愿,人类才能够登上月球。这是同~个
道理。”
事实上,对于许多当今的热点和难点话题,纳什均
没有给出答案,他只是说出了放之四海而皆准的道理,简
单而朴素。对此,记者则感触颇深。还记得在 1994年诺
贝尔经济学奖揭晓的那天下午,纳什在普林斯顿大学为其
举行的一个小型香槟酒会上说的话。他说自己不习惯发表
讲话,但这次他有三件事要说。其中一件事就是 ,他希望
获得诺贝尔奖可以改善他的信用评级,因为他实在太需要
一 张信用卡了。这位家喻户晓的数学界的 “梵高”其实就
是位朴素的老人,天才巨匠也是如此平凡。
有人说,天才往往桀骜不驯、 自高 自大,也常常招
人非议或受人崇拜。我们所熟悉的天才一般有两种类型 :
一 种就像我们大家一样 ,只不过更加卓越,而另一种就明
显具有非同寻常的智慧灵光 ,纳什的天才显然属于后一种。
这样的人无疑更有 “价值”,恒也更需要人们的理解和社
会的宽容。
t2,理学研究上有这样一种观点 :那些受到精神分裂
症困扰的人,往往具有很强的创造力。因为他们正是运用
创造力进行防御,使自己免受精神疾病困扰 ,那么他热切
地向往创造就一点也不奇怪了。还有人引申说 ,具有科学
天才的人,无论多么古怪反常,很少真的发疯,而这一点
就是创造力可能具备保护性的最强有力的证据。然而,遗
憾的是 ,纳什却越过了这一界限。
还好,庆幸的是,在纳什命运遭遇无法摆脱的厄运时,
他的妻子艾利西亚始终给予他无微不至的关怀和包容 ,纳
什因此最终战胜了病魔。此次论坛期间,纳什的妻子也一
同前来,并始终在台下静静聆听。在两位老人不时地相互
寻找的目光中,我们感受到他们共同走过的那段非同一股
的生命道路,那里面包含着相互理解、相互依恋、相互扶
助。对于约翰 ·纳什这位创建纳什均衡理论的数学大师来
说 ,他的个人命运经历是一个无法进行 “全面严格优势选
择”的博弈,但是,他依然幸运,在科学探索的道路上摘
到了智慧的金苹果,感受到了人间的美丽心灵。
See lohn Nash萱n Distinctive perspective
He still sattherequietly,immersedinhis ownworld.Hegotupto
leave,but was surrounded by the reporters.This is the sight at the mo-
mentNobel Laureates BeOing Forum 2011 wasAnnounced opening.He
isthe‘'gametheory'’master,a geniusmathematician John‘Nash.Ifyou
wantto findthemostdazzlingattentionduringtheforum,the”star'’who
isaskedfor signaturesandtakingpictureswiththemostmustgotohim.
Heisthe realprototypeinthattheMinistryofmonopoly4Oscar-
winningfilm ‘ ABeautifulMind,”Nash himselfwatchedthefilm and
gave aquite high evaluationtothe artistic achievements.He admitsthat
he read several times,but went through each time when watching.‘‘I
thinkthisfilm willhelppeopleun derstandandrespectpeoplewithmen-
tal illnesses.”
When startthe storyofNash,wefindhemadeamazingdiscoverin
ma th inthe 20s;he woninternationalreputationforhis economics gam e
theory.Then in his 30 years old,suffering from paranoid schizophrenia,
withthefrenzyinthedaysafterthepaininupto30yearsheneverableto
car/youtnormal course ofresearchwork.Hehasalwaysbeen aserious
illusion,auditoryhallucinations,thoughtdisorderandemotionaldistress,
and the willpower was completely destroyed.He gave UP mathematics,
numerologyand religionindulgein prophecy;Hefledto Europe many
tim es,hewas senttoamentalhospitalfor sixtimes...⋯
Six years ago,in July 2005,he accepted an exclusive interview
with China Financialyst correspondents,and was invited to board the
“Chinese financiers'’cover.W hile6years after;Nash seemsmore silent.
Inthe opening ceremonytwentyminutes,watching his aristocratic natu-
rallook,pure clear eyes,seehim sittingquietlyforevery admirer signa-
ture,ourheartswerefullofthe senseofbeingmoreemotionstouched,or
even forget this professional mission.
Nash went straight to the point in the speech after the opening
ceremony.He insisted on standing for nearly all hour talking about the
themehehaslongbeenthinkingof,thetopicofmoneyontheidea1.Ob—
viouslyNashhadmadeftdlpreparationswithtext-basedPlPTForserious
— — Geni¨S Giant with Simple Philosophy
By Guo Zichu
orother reasonswedonotknow,hewasreadingp~agraphlinebyline
wi th holdingthemicrophone.His soundswas low,his speedwas slow.
Interestingly,Nash often finished within the specified time,answered
questions succinctlyin interactive sessions;Leftus a deep impression of
a"simple attitudes”.
When was asked ‘‘in the currentworldofeconomic outlookbleak
situation,whatmeasures shouldUnited Statestaketopromotedomestic
economicgrowth?”Nash saidtheU.S.economi cproblemsbecome,like
a patient suffering from various diseases,there is no immediate e1.ire to
helpitoutofthewoods.Inhisview,theQuantitativeEasingpolicywill
resultin depreciationofthedollarandbringinginflation.But in the eco-
nomicsprofession,thereisalsoaview thatinflationwi llbring someben-
efits.‘'In PrincetonUniversitythereare scholarsbe fievethatthe Japanese
yendepreciatedto alarge—scalemeasuresto stimulate economi cgrowth,
andthatachieved some SuCCeSS,but Idonot agreewiththisview,forthis
approachhasitsvulnerability.’’
Asfortheissue of’Wh etherCbina'sbuyingU.S.bondsis safe or
not'’the answer is simple but quiteNashphilosophy:‘'Buy any country
bonds are a gamble,because these bonds are only paper bills and any
purchasermustbe carefulwhichinadditionto consideringeconomicfac—
tors,political factors also an important reason.‘'Although Nash did not
directly give the answer,but reminiscent ofhis answer with his”gam e
theory ‘'theory,thatisin a gam ble,alsomeansin theparties of struggle
.Theexistenceofthebehaviorfacethemostreasonable solution.
Such as helping the Italian out of the crisis,China’shooting in
Europe is ahottopic in recentacademic study.Nashpo inted out:‘'Many
people think that ifthe Chinese attempts to save Italy will most likely
gains somethingwhentheItalian stockindex roseinthefuture.Twodays
agowedefinitelysawthe stockmarket seemstorise abit,but overallto
thatthereare somepeople stillworryabout.‘‘
Not long ago,George Soros has said that the current crisis were
worse than in 2008.Th e ma in euro-zofle debtproblems ma yleadto the
2011年第10期卞目含髋宝l S
global economy facing financial and credit crunch.The current crisis is
serious,becausetheeHrodidnotuseanappropriatebody,amechanism to
solvethedebtproblemsoftheeuro area.
Whenaskedt0makeacommentonSoros’sview,Nash said:~dnk-
I had seentrim atPrincetonUniversity economics conference,heis a
veryintelligentperson,butI doesnotknowwhetherhis view is correct,
becauseitisdifficulttopredictthe sameas weather,whilethe economi c
crisis can not be determinedbased solely onthe people’spoint ofview
,
but a simplepanicmightnothave abigproblem,andonlywhen awide
rangeoffellwouldthecompanyappearedtoproduceeffects.
EuropeanandAmerican debt crisisworsened,themajorWestem
powers seem to fall into the dilemma the government’s dilemma,Are
there good resolvationstothe crisis?Wh en a reporters lookingforward
to some suggestions givenbyNash,hejustmade alogicaland simple
answerlikethis:‘qhere is a saying called‘whenthisis awill,thereis a
way’,ifthesegovemmentsare strongenoughwill,thentheycancomeup
with aneffectiveway to resolvethecrisis.Becauseofthe strongwill,hu-
man beingswillbe abletolandonthemoon.Thisisthe sanle reason.‘‘
Infact,formanyoftoday’shotanddifficulttopic,Nashdidnotgive
the answer,hejust say a universal truth,simple and plain.This is Nash
Style.Let’s go backtothat afternoon in 1994 at a small conference for
his champagneinNobelPrizeinEconomics,He saidhewas notaccus—
tomedto speak,buthehadthreethingsto say,while onethinghehope s
theNobelPrizetoimprovehis creditrating,becausehehadtoo needed a
credit card.The well-known‘'Van Gogh'’in mathematical communityis
actuallyabitplainoldgenius masterwith soordinaryandbeautifulheart.
Itis saidthatgenius isoftenrebellious,arrogm~,oftencriticizedbyoth-
ers,orworship.Wearefamiliarwiththetwogeneraltypes:oneisthe sameas
us but even more remarkable,andthe otherobviously has all e)(Ⅱa0删jnaIy
intelligenceEmmanuel,Nash’sgenius isclearlythelatter.Thisnodoubtmore
‘'value'’,butalsoneedpeopleunderst~dsandsocialtolerance.
Psychological research carries such view:schizophrenia that are
troubled,often hi ly creative.Because they take the creative use for
defense,andtoprotectthemselvesfrom mentalillnessproblems,soitis
not surprisingthatheeagerlydesiretocreate.Alsoextendedthatscientific
genius who,no ma tter how strange anomaly few really crazy,and this
may have the most powerful evidence for the protection ofcreativity.
However,thatNashhascrossed thisthreshold.
Fortunately,when Nash wentthrough the tortures ofescaping the
fate,hiswifeAliciahasalwaysbeengivinghim everypossible careand
inclusion,and accompany him together to the final victory over his ill-
ness.Duringtheforum,Nash’swife comestogethertolisten his speech.
From timeto timethetw o old people contacted with each other’s eyes.
Wefeelthattheyhave beentogetherduringthe hardperiodlifewithmu-
tualunderstanding,mutualattachment,andmutual suppo rt.
Maybe as amathematicalmaster created equilibrium theory John
Nash’s experience is a personal fate can not be“comprehensive and
rigorous selection advantage”ofthe game,but he is still lucky,picking
thewisdom golden applein the scientific exploration road,alsofeelthe
beautyofhuman sou1.
following by P52
rency.TheaccusationthatChinaisacurrencymanipulatordoesnotmake
any sense.
“What,sthe attitude shouldwetakeforthe statusandvalue ofthe
yuan”is a quesfionthattheWestern countriesandChinahas been focus
on debate.As Mundell once said in 2005:“Some people say that my
standing onthe R 佃 exchange rate issue is from alove ofthe Chinese
ratherthanthe economist’s.InfactIadvocated 35yearsago suchallidea,
theworld’s economy shouldhaveafixedcurrencyregime.“
In the Nobel Forum.Mundell reiterated his view:“China is not
manipulating its currency,and early in 2005 China has reformed its ex-
change ratemechanism.even after 2008thereislittleinterventioninthe
foreign exchangemarket.Th erefore theaccusationthatChinais currency
manipulatordoesnotmake sense.“
]广}le real intent for those who believe that China’s exchange rate
isundervalued istorevaluetheyuan.Earlyin July2005.theRMBhas
appreciated 10%.Mundell believesthatifthe accelerating pace ofyuan
56 I CHINA FlNANClALYSlT oC 2011
appreciation,the economymay havebeen affected.So currency appre-
ciation shouldbe controlled atlessthan 9% or 10%.orthe exchange rate
、viIIadverselyaffectthedynamicbalance.
MundeU stressed that remaining the RMB exchange rate relatively
stablewillalsohelpChinacontrolinflation.Inflation,incounlriesthatbalance
ofpaymentssurplus moreareinevilzble,thisisnotabigpmblernforChina.
In the past decade,China have gone through a certain am ount of
inflation.especiallyin2004theinflationwas evenexceeded 5%.Infact,
there is some kind of inflation in many European countries,but they
maintain the exchange rate criteria,andtake the euro currency.IfChina
can continueto stabilizetheexchangerate,theprice can beachieved rela-
five stability.
Each ofthe Nobel Forumis our close contact andthe oppommity
幻Mundel1.Mundellwanteach eventcouldbecome‘'adviceand sugges-
tions”momentforChina.Indeed,everytimehis arrival also broughtus
theideaofwisdomfeast.