Is the Christmas card obsolete? I suppose the answer depends on what function you think the Christmas card is intended to serve, if any at all. Surely it is no longer intended to convey information. Email and social networks do a more efficient job, and including a Christmas newsletter or family photograph (I do both) will earn you only scorn from any self-respecting British snob.
圣诞卡过时了吗？我认为答案取决于在你心目中圣诞卡应该承载什么功能（如果你认为它有任何功能的话）。毫无疑问，圣诞卡已经不再用来传达信息。电子邮件和社交网络比圣诞卡更有效，如果你在圣诞卡里加上圣诞简报或者家人照片（我两个都加），只会让任何自命不凡的英国人对你投来白眼。
Some believe that the Christmas card list, where we keep track of old favours and slights, is a sort of passive-aggressive vendetta. There is truth in this. Late in 1974, two sociologists, Phillip Kunz and Michael Woolcott, posted more than 500 Christmas cards to people they did not know. Some of them were “high status” cards, using expensive materials and signed “Dr and Mrs Phillip Kunz”. Others were from “Phillip and Joyce Kunz” or used cheaper stationery or both.
有人认为，记录着我们之前得到过的帮助和受过的怠慢的圣诞卡寄送名单，是一种消极的复仇。这话有些道理。1974年末，社会学家菲利普•孔兹(Phillip Kunz)和迈克尔•伍尔科特(Michael Woolcott)向陌生人寄出了500多张圣诞卡。其中一些是“高尚”卡片，纸质精良，署名为“菲利普•孔兹博士夫妇”。其他一些卡片或是署名为“菲利普和乔伊丝(Joyce)•孔兹”，或是纸质较差，抑或两者皆是。
The Kunz family received, along with a complaint from the police, some rather touching replies: “Dear Joyce and Phil, Received your Christmas card and was good to hear from you. I will have to do some explaining to you. Your last name did not register at first . . . Please forgive me for being so stupid for not knowing your last name. We are fine and hope you are well. We miss your father. They were such grand friends.”
“孔兹一家”除收到了一封来自警方的抗议信以外，还收到了一些相当感人的回复：“亲爱的乔伊斯和菲尔，我已经收到了你们的圣诞卡，收到你们的消息真是太好了。我必须向你们做些解释。一开始我没认出你们的姓……请原谅我如此愚蠢，不知道你们的姓。我们很好，希望你们也好。我们想念你的父亲。他们真是很好的朋友。”
But what is most striking is that more than 100 strangers felt obliged to send a signed card in response. That is the power of reciprocity. (Response rates were particularly high if “Dr Kunz” had written on a fancy card to a working-class household. That is the power of status.)
但最惊人的是，有逾100个陌生人认为有必要回寄一张手写的卡片。这就是礼尚往来习俗的力量。（寄给工人阶层家庭的署名“孔兹博士”的高档卡片回复率格外高。这就是社会地位的力量。）
If this is what Christmas cards are all about — mindless reciprocal obligation coupled with some social climbing — then I think we can all agree on two things: we could do without them; and we’ll never be rid of them. Thomas Schelling, a winner of the Nobel Memorial Prize for Economics, once advocated a bankruptcy procedure — wiping clean the list of people to whom we “owe” a Christmas card. If only.
如果这就是圣诞卡的意义所在——机械的礼尚往来义务、加上一点攀高枝活动，那么我认为所有人应该都同意以下两点：我们可以没有圣诞卡；并且我们永远不会摆脱圣诞卡。诺贝尔经济学奖得主托马斯•谢林(Thomas Schelling)曾经提议采取某种“破产”程序，把我们“欠”下的圣诞卡债清零。我们要是真能这样做就好了，可惜……
But perhaps the Christmas card also serves other purposes. Consider the exchange, “How do you do?”, “How do you do?” This is phatic communication. It conveys no detailed information but it acknowledges others and implies that there is nothing much to report. “I’m OK, and you’re OK, and lines of communication are open if that changes.”
但圣诞卡或许还承载了其他功能。想想这样的交谈，“你好吗？”，“你好吗？”。这是一种交际对话。这段对话没有传达任何具体信息，只是向别人打招呼，并暗示没什么值得一说的事情。“我很好，你也很好，如果出了什么事，尽管告诉我。”
A Facebook “poke” could achieve the same thing at much lower cost. But perhaps the expense and the hassle is part of the point. If someone invites you for dinner and you say “thank you” as you leave, you may still wish to follow up with a thank-you note to show that you have enough invested in the relationship to take the trouble. If relationships weren’t hard work, they would not be relationships.
Facebook的“戳一下”(poke)能够以低得多的成本达到同样的效果。但或许寄圣诞卡的部分意义恰恰在于它费钱费事。如果有人邀请你吃饭，你在离开时也说了“谢谢”，你可能还是希望在晚些时候再写一份道谢便条，以示你对这份关系足够重视，愿意费这个事。不需要花费精力维护的人际关系就不是人际关系了。
There’s a thing called the “social brain” hypothesis: it states that humans evolved large and energy-intensive brains not to do hard sums or design clever tools but because they needed them to navigate the complexities of dealing with other people. Back in 1992, Robin Dunbar — an anthropologist and psychologist now based at the University of Oxford — published a fascinating addendum to that idea. Dunbar had been looking at the social group size and the brain size of different primates, and found that primate species with larger neocortices had grooming relationships with larger social groups. Extrapolating to humans, he produced what has become known as Dunbar’s Number. If our brains are any guide, we’re built to handle a social network of about 150 people.
有一个所谓“社会大脑”假说认为：人类进化出消耗大量能量的大体积大脑，不是为了进行复杂的运算，也不是为了设计巧妙的工具，而是因为人需要大脑来应对复杂的人际交往。早在1992年，现任职于牛津大学(Oxford)的人类学家和心理学家罗宾•邓巴(Robin Dunbar)就发表了一篇非常有趣的文章，对这一思想进行了补充。当时邓巴对不同的灵长类动物的社群规模和脑部大小进行了比对研究，发现新皮层更大的灵长类物种在更大的社群内相互梳理毛发。推及人类，他提出了所谓的“邓巴数字”(Dunbar’s Number)。如果可以进行这样的推断的话，那么以人类的大脑，每个人应该能应付大概150个人的社交网络。
Dunbar’s Number is both more uncertain and more complex than popular presentations would have you believe. Dunbar himself argues that social networks are nested, following rough powers of three: five people to whom we might turn for substantial emotional or financial support in a moment of true crisis; 15 intimate friends; 50 friends; 150 rather casual friends, and so on.
流行的解读会让你觉得邓巴数字是一个确定而简单的原则，但实际上它要更不确定、也更复杂一些。邓巴本人认为，社交网络的构建大致遵循三倍原则：你在真正遇到麻烦时会向他们寻求实质性情感或者财务支持的密友有5个人；比较亲密的朋友有15个人；关系较好的朋友有50个人；泛泛之交则有150个人，以此类推。
Social networking tools let us reach more people, more quickly, and in some detail if we so choose. I can reach 90,000 followers on Twitter but — how can I put this tactfully? — they are not my friends. These new technologies are a great convenience but it is not clear that they are allowing us to expand the number of genuine friends that we have. A recent study by Bruno Gonçalves, Nicola Perra and Alessandro Vespignani examined 25 million conversations between Twitter users, and found that the network with whom people might actually have several reciprocal conversations was between 100 and 200 — Dunbar’s number again. As for close friends, women engage in two-way communication with around six people on Facebook; men with just four.
社交网络工具让我们能以更快的速度接触到更多的人，如果我们愿意，这些工具还能帮助我们进行比较详细的接触。我在Twitter上能接触到9万名粉丝，但是，我该怎么委婉地说呢，他们不是我的朋友。这些新科技给我们提供了很大的便利，但并无明显迹象显示它们能让我们得以扩展真朋友的数量。布鲁诺•贡萨尔维斯(Bruno Gonçalves)、尼古拉•佩拉(Nicola Perra)和亚历山德罗•韦斯皮尼亚尼(Alessandro Vespignani)最近进行了一项研究，他们查看了Twitter用户间的2500万次对话，发现人们可能进行几次相互对话的社交网络大概包含100到200人——这又印证了邓巴数字。至于密友，女性在facebook上大概与6个人进行双向交流；而男性仅与4个人保持这种关系。
Much like primate grooming, a Christmas card requires effort, time and expense. An up-to-date Christmas list requires some thought about who matters to you, for reasons noble or ignoble. And a few years ago, two researchers carefully examined how big Christmas cards lists tended to be, once allowing for the fact that a single card could reach several members of a household. The researchers were Russell Hill and Robin Dunbar. And the number of people reached by a typical British Christmas card list? 154.
与灵长类相互理毛的举动很像，圣诞卡需要花费精力、时间和金钱。要列一份最新的圣诞卡寄送名单，你需要思考一下谁对你来说很重要，不管是出于光明正大的理由，还是上不了台面的理由。几年前，两名研究者仔细研究了圣诞卡寄送名单的一般长度，并考虑一张卡片可以同时接触到同一个家庭中的好几个人的事实。这两名研究者分别是拉塞尔•希尔(Russel Hill)和罗宾•邓巴。那么在英国，一张圣诞卡片寄送名单通常能接触到多少个人？答案是154个。