Most people dream enthusiastically at night, their dreams seemingly occupying hours, even though most last only a few minutes. Most people also read great meaning into their nocturnal visions. In fact, according to a new study in the Journal of Personality and Social Psychology, the vast majority of people in three very different countries — India, South Korea and the United States — believe that their dreams reveal meaningful hidden truths.

According to the study, 74% of Indians, 65% of South Koreans and 56% of Americans hold an old-fashioned Freudian view of dreams: that they are portals into the unconscious.

But after so many years of brain research showing that most of our everyday cognitions result from a complex but observable interaction of proteins and neurons and other mostly uncontrolled cellular activity, how can so many otherwise rational people think dreams should be taken seriously? After all, brain activity isn't mystical but — for the most part — highly predictable.

The authors of the study — psychologists Carey Morewedge of Carnegie Mellon University and Michael Norton of Harvard — offer a few theories. For one, dreams often feature familiar people and locations, which means we are less willing to dismiss them outright. Also, because we can't trace the content of dreams to an external source — because that content seems to arise spontaneously and from within — we can't explain it the way we can explain random thoughts that occur to us during waking hours. If you find yourself sitting at your desk and thinking about a bomb exploding in your office, you might say to yourself, "Oh, I watched 24 last night, so I'm just remembering that episode." But people have a harder time making sense of dreams. Maybe 24 caused the dream, we think — or maybe we're having a premonition of an attack. We love to interpret dreams widely, and those acts of interpretation give dreams meaning.

Human beings are irrational about dreams the same way they are irrational about a lot of things. We make dumb choices all the time on the basis of silly information like racial bias or a misunderstanding of statistics — or dreams. Morewedge and Norton quote one of the most famous modern studies to demonstrate our collective folly, from a paper written by psychologists Amos Tversky and Daniel Kahneman that was published in Science in 1974. In that paper, Tversky and Kahneman discuss an experiment in which subjects were asked to estimate the percentage of African countries represented in the U.N. Before they guessed, a researcher spun a wheel of fortune in front of them that landed on a random number between 0 and 100. People tended to pick an answer that wasn't far from the number on the wheel, even though the wheel had nothing to do with African countries.

Countless experiments over the ensuing decades have confirmed that most of us make this so-called anchoring mistake — that is, making a decision based largely on an unrelated piece of information, like a random number that appears on a wheel. Anchoring occurs all the time, like when you're asked to look at your Social Security number before answering a question (you're more likely to pick an answer close to the digits in your SSN). A team of researchers even showed in a 2003 paper in the Quarterly Journal of Economicsthat people will endure more physical discomfort (exposure to an unpleasant noise) for less monetary compensation in a lab setting when they are anchored prior to the experiments to smaller monetary amounts. As I said, we all make dumb choices based on silly information. That's why we invest meaning in dreams.

That being said, dumb choices aren't necessarily bad ones. A final finding from the study: When people have dreams about good things happening to their good friends, they are more likely to say those dreams are meaningful than when they have dreams about bad things happening to their friends. Similarly, we invest more meaning in dreams in which our enemies are punished and less meaning in dreams in which our enemies emerge victorious. In short, our interpretation of dreams may say a lot less about some quixotic search for hidden truth than it does about another enduring human quality: optimistic thinking.

大多數(shù)人晚上很愛(ài)做夢(mèng)，人們的夢(mèng)似乎占據(jù)了大部分時(shí)間，即使有的只持續(xù)幾分鐘。事實(shí)上，根據(jù)《個(gè)性-社會(huì)心理月刊》的研究，來(lái)自三個(gè)迥異國(guó)家的大部分人（包括印度，韓國(guó)及美國(guó)）相信他們的夢(mèng)揭示了頗具意義的隱匿事實(shí)。

  研究表明，74%的印度人，65%的韓國(guó)人和56%的美國(guó)人對(duì)夢(mèng)的看法仍舊是古老的弗洛伊德式——也就是夢(mèng)是無(wú)意識(shí)的入口。

  但這么多年對(duì)大腦研究表明，大多數(shù)的日常認(rèn)知都源于復(fù)雜且明顯的蛋白質(zhì)與神經(jīng)細(xì)胞的關(guān)系和大多數(shù)不受控制的細(xì)胞活動(dòng)。畢竟大腦活動(dòng)并不神秘——但總的來(lái)說(shuō)——還是可以預(yù)測(cè)的。

  此項(xiàng)研究的作者——卡內(nèi)基梅隆大學(xué)的心理學(xué)家Carey Morewedge和哈佛大學(xué)的米歇爾.諾頓，他們提供了一些理論。夢(mèng)境顯現(xiàn)的都是熟悉的人和場(chǎng)景，也就是會(huì)說(shuō)我們不愿意讓它徹底散去。因?yàn)槲覀儾⒉荒軓谋硐筇剿鲏?mèng)的內(nèi)容——因?yàn)閮?nèi)容似乎是從里到外自發(fā)產(chǎn)生的——因而我們不能以清醒時(shí)解釋胡亂想法的方式對(duì)待它。如果你發(fā)現(xiàn)自己坐在桌子上想著辦公室里有一個(gè)正爆炸的炸彈，你也許會(huì)對(duì)自己說(shuō)：“哦，我昨晚看了《24小時(shí)》，所以我只是回憶起了那個(gè)情節(jié)。”但人們還是很難弄懂夢(mèng)的含義。我們認(rèn)為也許《24小時(shí)》引起了夢(mèng)——或許我們只是有了一次非難的預(yù)兆。

  人們喜歡廣泛地解釋夢(mèng)境，那些解釋也給夢(mèng)賦予了意義。

  人類(lèi)在許多事情上都很不理性，對(duì)待夢(mèng)也是如此。我們時(shí)刻根據(jù)諸如種族偏見(jiàn)之類(lèi)愚蠢的消息，對(duì)數(shù)據(jù)的曲解，以及夢(mèng)做著無(wú)聲的選擇。Morewedge和Norton引述了最著名的研究之一來(lái)證明我們共有的愚蠢，那就是心理學(xué)家Amos Tversky和Daniel Kahneman于1974年發(fā)表的論文。在那篇論文里Tversky和 Kahneman討論了一個(gè)實(shí)驗(yàn)，實(shí)驗(yàn)中對(duì)象被要求估計(jì)聯(lián)合國(guó)里非洲成員國(guó)所占比例。在他們猜測(cè)之前，研究員在他們面前轉(zhuǎn)了命運(yùn)之輪，它最終會(huì)停止在0到100之間的偶然數(shù)字上，人們?cè)噲D在輪子上就近找一個(gè)答案，即使這輪子跟非洲國(guó)家沒(méi)有關(guān)系。

   隨后幾十年中無(wú)數(shù)的實(shí)驗(yàn)證明我們中大多數(shù)人犯了依賴(lài)性強(qiáng)的錯(cuò)誤，那就是太過(guò)依靠一個(gè)不相關(guān)的消息做決定，就像在輪子上偶然出現(xiàn)的數(shù)字。希望時(shí)時(shí)會(huì)出現(xiàn)，就像你在回答問(wèn)題之前被要求查看社會(huì)保險(xiǎn)號(hào)。（你很可能會(huì)選一個(gè)接近社會(huì)保險(xiǎn)號(hào)的答案）一組研究人員在一篇2003年經(jīng)濟(jì)季刊的論文中向我們顯示，人們?cè)趯?shí)驗(yàn)前被固定在小一些的資金范圍內(nèi)時(shí)，進(jìn)行實(shí)驗(yàn)室調(diào)整時(shí)為了少繳賠償金，人們會(huì)忍受更多身體上的不適（據(jù)說(shuō)是讓人不悅的噪音）我們總是根據(jù)愚蠢的消息無(wú)言地選擇。這就是我們?yōu)槭裁磳?duì)夢(mèng)賦予意義。

  那也就是說(shuō)，沉默的選擇并不一定是壞事。來(lái)自研究的最終結(jié)論是，相比于夢(mèng)到好朋友遭遇壞事，當(dāng)人們夢(mèng)到好事降臨到好朋友身上時(shí)，他們會(huì)更傾向于將之賦予意義。同樣，我們會(huì)將敵人受到懲罰的夢(mèng)境賦予意義，而對(duì)敵人勝利的夢(mèng)境相反處之。簡(jiǎn)而言之，我們對(duì)夢(mèng)的解釋會(huì)很少空想性地探尋隱匿的事實(shí)，而更多的是體現(xiàn)了人類(lèi)的另一種永久性特質(zhì)：凡事都往好處想。