上周六,奧斯卡獲獎(jiǎng)影片《美麗心靈》主人公的原型、美國(guó)數(shù)學(xué)天才、諾貝爾獎(jiǎng)得主約翰•納什遭遇車(chē)禍去世,終年86歲。事故發(fā)生時(shí),納什夫婦乘坐的一輛出租車(chē)在新澤西高速路上與另外一輛汽車(chē)相撞,納什82歲的妻子艾麗西亞也在車(chē)禍中遇難。出租車(chē)司機(jī)以及對(duì)方車(chē)輛的司機(jī)都沒(méi)有遭受致命傷。
Born in West Virginia in 1928, Nash displayed an acuity for mathematics early in life, independently proving Fermat’s little theorem before graduating from high school. By the time he turned 30 in 1958, he was a bona fide academic celebrity. At Princeton, Nash published a 27-page thesis that upended the field of game theory and led to applications in economics, international politics, and evolutionary biology. His signature solution—known as a “Nash Equilibrium”—found that competition among two opponents is not necessarily governed by zero-sum logic. Two opponents can, for instance, each achieve their maximum objectives through cooperating with the other, or gain nothing at all by refusing to cooperate. This intuitive, deceptively simple understanding is now regarded as one of the most important social science ideas in the 20th century, and a testament to his almost singular intellectual gifts.
1928年,納什出生在美國(guó)西佛吉尼亞州。他很早就表現(xiàn)出出色的數(shù)學(xué)天賦,高中還未畢業(yè)就已經(jīng)獨(dú)立證明了費(fèi)馬小定理。1958年,而立之年的納什已是名副其實(shí)的學(xué)術(shù)界名人。在普林斯頓,納什一篇27頁(yè)的論文顛覆了博弈論領(lǐng)域,博弈論此后被廣泛應(yīng)用于經(jīng)濟(jì)學(xué)、國(guó)際政治以及進(jìn)化生物學(xué)領(lǐng)域。著名的解決方案“納什均衡”就是由他發(fā)現(xiàn)并以他的名字命名。“納什均衡”指博弈雙方不一定受到零和邏輯的約束,比如,博弈雙方可以通過(guò)合作均取得最大收益,或者不合作承擔(dān)零收益(但也沒(méi)有損失)。這表面看來(lái)似乎很好理解的理論卻已經(jīng)成為20世紀(jì)最重要的社會(huì)學(xué)觀(guān)點(diǎn)之一,而這也是納什卓越智慧的明證。
But in the late 1950s, Nash began a slide into mental illness—later diagnosed as schizophrenia—that would cost him his marriage, derail his career, and plague him with powerful delusions. Nash believed at various times that he was the biblical figure Job, a Japanese shogun, and a “messianic figure of great but secret importance.” He obsessed with numbers and believed The New York Times published coded messages from extraterrestrials that only he could read.
但是,自1950年代末,納什開(kāi)始受到精神疾病的折磨,經(jīng)診斷他患上了精神分裂癥。他因此離婚,事業(yè)毀于一旦,他自己也飽受幻覺(jué)的折磨。他時(shí)而以為自己是圣經(jīng)中的約伯,時(shí)而把自己當(dāng)做日本古代的將軍,時(shí)而又以為自己是“隱秘而偉大的救世主”。他沉溺于數(shù)字之中,堅(jiān)信《紐約時(shí)報(bào)》中藏匿著外星人留下的密碼,而只有他才能解開(kāi)。
Mental institutions and electroshock therapy failed to cure him, and for much of the next three decades, Nash wandered freely on the Princeton campus, scribbling idly on empty blackboards and staring blankly ahead in the library. Atlantic contributor Robert Wright, an undergraduate at Princeton in the late 1970s, remembers Nash as “some math genius that went crazy” who wore colorful sneakers and quietly watched people. His schizophrenia removed him completely from his work. By the time Nash was awarded the Nobel prize in Economics in 1994 (along with John Harsanyi and Reinhard Selten), he hadn’t published a paper in 36 years.
精神病院、電擊療法都沒(méi)能治愈納什。在隨后的三十年間,他游蕩在普林斯頓的校園里,或在空黑板上“涂鴉”,或在圖書(shū)館中發(fā)呆?!洞笪餮笤驴纷迦肆_伯特•賴(lài)特是普林斯頓1970年代的畢業(yè)生,他回憶到:這位“瘋了的數(shù)學(xué)天才”總是穿著彩色的運(yùn)動(dòng)鞋,安靜地看著人來(lái)人往。精神分裂讓他完全無(wú)法工作,直至1994年(與約翰•海薩尼 、萊因哈德•澤爾騰共同)獲得諾貝爾經(jīng)濟(jì)學(xué)獎(jiǎng)的36年間,納什再無(wú)論文發(fā)表。
But like a child cured of a nightmare by the switch of a light, Nash recovered from his illness seemingly by choosing not to be sick anymore. “I emerged from irrational thinking, ultimately, without medicine other than the natural hormonal changes of aging,” he wrote in 1996. Five years later, the release of the film A Beautiful Mind, based on Sylvia Nasar’s 1998 book of the same name, amplified Nash’s extraordinary life story to an international audience. He continued to work, travel, and speak at conferences for the rest of his life.
就像打開(kāi)燈就能讓孩子走出夢(mèng)魘一般,決定不再做病人后納什似乎就自己擺脫了病魔。1996年,他寫(xiě)到:“最終,我擺脫了妄想,不是依靠藥物,而是隨著年紀(jì)見(jiàn)長(zhǎng)體內(nèi)激素自然而然發(fā)生了變化。”5年后,根據(jù)1998年西爾維婭•娜薩同名小說(shuō)改編的電影《美麗心靈》上映,納什與眾不同的故事為全世界觀(guān)眾所知。而故事的主人公在接下來(lái)的人生中依舊繼續(xù)工作、旅行、在大大小小的會(huì)議上發(fā)言。
It’s tempting to wonder what Nash might have accomplished had mental illness not robbed him of so many productive years. But the “beautiful mind” that gave him such prodigious mathematical talent was indivisible from the one which spawned powerful delusions. In her study of creativity published in the July/August 2014 edition of the Atlantic, Nancy Andreasen related a memorable anecdote from Nasar’s book. Upon visiting Nash at a mental institution, a colleague asked how a man so devoted to reason and logical truth could believe that extraterrestrials were sending him messages.
人們也許不禁想問(wèn),如果沒(méi)有這么多年精神疾病的困擾,納什又將取得怎樣的成就?他的美麗心靈既帶給了他巨大的數(shù)學(xué)成就,同時(shí)也讓他飽受幻覺(jué)的折磨。《大西洋月刊》7/8月刊中,南希•安卓森關(guān)于創(chuàng)造力的一篇文章就提到了娜薩書(shū)中一個(gè)令人難忘的故事:納什的一個(gè)同事去精神病院看望他時(shí),曾問(wèn)他,身為一個(gè)如此執(zhí)著于理性與邏輯真理的人,他為何會(huì)相信外星人傳遞信息這種事。
“Because the ideas I had about supernatural beings came to me the same way that my mathematical ideas did,” replied Nash. “So I took them seriously.”
納什答道:“因?yàn)槟切╆P(guān)于超自然生物的想法向我襲來(lái),就仿佛曾經(jīng)的那些數(shù)學(xué)觀(guān)點(diǎn)一樣。于是,我當(dāng)真了。”