文艺；书评；人类的决策；聪明不在；

　　Thinking Fast and Slow, by Daniel Kahneman.

　　《思考，快与慢》丹尼尔·卡尼曼著。

　　Towards the end of “Thinking, Fast and Slow”, Daniel Kahneman laments that he and his late collaborator, Amos Tversky, are often credited with showing that humans make “irrational” choices. That term is too strong, he says, to describe the variety of mental mishaps to which people systematically fall prey. Readers of his book may disagree. Mr Kahneman, an Israeli-American psychologist and Nobel economics laureate, has delivered a full catalogue of the biases, shortcuts and cognitive illusions to which our species regularly succumbs. In doing so he makes it plain that Homo economicus—the rational model of human behaviour beloved of economists—is as fantastical as a unicorn.

　　在《思考：快与慢》一书的结尾之处，丹尼尔卡内曼说对人们的一些赞誉感到悲痛，人们赞赏他和他已故的合作者阿莫斯特沃斯基发现了人类做“无理性决定”，他说，用这个说法来形容“人们可能受到的各种方的面精神问题的困扰太严重了”。这本书的读者也许不赞同这个说法。卡内曼拥有以色列和美国双重国籍，心理学家，诺贝尔经济学奖获得者，他将人类通常会有的偏见，心理捷径，和认知幻象进行了系统全面的分类并清晰的阐释了新鲜的“经济人”的概念（Homo economicus），这是经济学家所钟爱的人类行为的理性分类。

　　In one experiment described by Mr Kahneman, participants asked to imagine that they have been given 50 pound behave differently depending on whether they are then told they can “keep” 20 pound or must “lose” 30 pound—though the outcomes are identical. He also shows that it is more threatening to say that a disease kills “1,286 in every 10,000 people”, than to say it kills “24.14% of the population”, even though the second mention is twice as deadly. Vivid language often overrides basic arithmetic.

　　卡内曼描述了一个实验：要求实验参与者想象他们每人得到50英镑，尽管结果一样—都被告知他们只能留下20镑，而必须要损失30镑，但他们每个人表现却大不相同。卡内曼还告诉我们，如果说一种疾病使每10000人中有1286人死亡，或者表述为它使占人口总数的24.14%的人死亡，尽管后者的死亡人数是前者的两倍，但前者更有震慑力。形象生动的语言比简单的数字更为感染力。

　　Some findings are downright peculiar. Experimental subjects who have been “primed” to think of money, perhaps by seeing a picture of dollar bills, will act more selfishly. So if someone nearby drops some pencils, these subjects will pick up fewer than their non-primed counterparts. Even obliquely suggesting the concept of old age will inspire people to walk more slowly—though feeling elderly never crossed their mind, they will later report.

　　有些实验结果十分奇怪。那些在看到美元的图像，更容易想到钱的人的实验参与者通常会表现得更为自私。如果坐在他们身旁的人有人掉了铅笔，相比较那些没那么容想到钱的人，他们肯弯腰捡起笔的几率要大大降低。这甚至间接地暗示：想到老年的意象会使人们走路速度放缓—尽管他们自己从没有老年的感觉，这些结论稍后将后发布。

　　After all this the human brain looks less like a model of rationality and more like a giddy teenager: flighty, easily distracted and lacking in self-awareness. Yet this book is not a counsel of despair. Its awkward title refers to Mr Kahneman's two-tier model of cognition: “System 1” is quick, intuitive and responsible for the quirks and mistakes described above (and many others). “System 2”, by contrast, is slow, deliberative and less prone to error. System 2 kicks in when we are faced with particularly complex problems, but much of the time it is all too happy to let the impulsive System 1 get its way. (Readers may be reminded of Freud's “id” and “superego”, though Mr Kahneman never mentions this particular intellectual ancestor.)

　　最后，作者得出结论，与其说人类的大脑是理性的集合，还不如说它更像一个轻浮的少年：反复无常，容易分神，缺少自觉意识。当然这本书不是人们悲观的忠告。书的标题有些拗口，但它表明了卡内曼'对认知的双层分类模型：“系统一，快速，受直觉引导，易犯上述的错误。相比之下，系统二则缓慢，慎重思考，不易犯错误。只有当我们面临着复杂的问题时，系统二才会启动，更多的时候，是让受直觉影响的系统一来替我们做决定。（读者可能会想到弗洛伊德的“本我”“超我”，但卡内曼在书中压根没有提这位贡献卓著的前人）

　　What, then, is System 1 good for? Rather a lot, it turns out. In a world that often demands swift judgment and rapid decision-making (fight or flight?), a creature who solely relied on deliberative thinking wouldn't last long. Moreover, System 1 generally works well. As Mr Kahneman says, “most of our judgments and actions are appropriate most of the time”. He urges readers to counteract what he considers to be mistakes of System 1 thinking, such as the “loss aversion” that deters people from accepting favourable gambles (such as a 50-50 chance to win 200 dollar or lose 100 dollar). He also recommends checking the performance of an investment portfolio no more than once a quarter, to limit needless anguish over short-term fluctuations and the “useless churning” of shares.

　　那么，系统一适合做什么呢？答案是：很多。在这个世界里，我们常常需要迅速做出判断，并快速做出决定（开战与否？）一个人不能只是依靠深思熟虑，这样是不行的。并且，系统一通常可以很好的运行。正如卡内曼所说：“我们大部分的判断和决策通常都很合理”他建议读者自觉避免系统一思考方式会犯的错误，例如“讨厌损失”会让人们不愿接受有利可图的打赌（比如，有一半对一半的机会来赢200美元或者损失100美元）他也强烈建议我们每次在观察证券投资的行情时考虑的时间不要超过15分钟，这样会减少我们对短期内股价的浮动和调整不必要的担心。

　　Mr Kahneman does not dwell on the possible evolutionary origins of our cognitive biases, nor does he devote much time to considering why some people seem naturally better at avoiding error than others. Still this book, his first for a non-specialist audience, is a profound one. As Copernicus removed the Earth from the centre of the universe and Darwin knocked humans off their biological perch, Mr Kahneman has shown that we are not the paragons of reason we assume ourselves to be. Often hailed as the father of behavioural economics (with Tversky as co-parent), his work has influenced a range of disciplines and has even inspired some policy.

　　卡内曼并没有详述我们认知偏见的进化源头，也没有花太多笔墨解释为什么有些人天生就比其他人善于规避错误。但他的这本书作为给大众的普及型读物是十分出色。正如哥白尼提出了地球是宇宙的中心，达尔文指出人类不是万物之灵，卡内曼也展示了我们人类并没有自己想象的那样充满理性的智慧。卡内曼被人们称为行为经济学之父（和特沃斯基并称），他的理论影响了许多学科，甚至给一些政策的制定提供了参考。

　　But the true consequences of his findings are only starting to emerge. When he presents the poor victims of his experiments with conclusive proof of their errors, the typical reaction is not a chastened pledge to shape up, but confused silence, followed by business as usual. No one likes to be told he is wrong.

　　基于他的发现，其真正结论现在才开始显现出来。当他拿出确凿的证据给可怜的实验者们看，来证明他们的错误时，人们明显的反应不是发誓改正这些错误，而是非常困惑的保持了沉默，紧接着，一切又回归原样。没有人喜欢别人告诉自己做错了。