There 8217;s an old puzzle, from before the daysof cell phones, that goes something like this:
在手机出现之前的时代，有一个古老的谜题：
Suppose you 8217;re meeting a friend in anAmerican town that neither of you have been to before. You don 8217;t have a chanceto plan a meeting place beforehand. Where do you go?
假设你要在一个美国小镇见一个朋友，但你们俩都从来没有去过那里。你们事先也不能约定见面地点，那么你会去小镇上的哪个地方？
The author of the puzzle suggested that thelogical solution would be to go to the town 8217;s main post office and wait at themain receiving window, where out-of-town packages arrive. His logic was thatit 8217;s the only place that every town in the US has exactly one of, and whicheveryone would know where to find.
这个谜题的作者建议，一个理性的做法是去小镇上的主要邮局，等在主收信窗口，所有来自于小镇之外的邮件都会先到达这个地方。这种方法的逻辑在于这个地点在每个美国小镇中都只有唯一一个，因而所有人都知道它在哪里。
To me, that argument seems a little weak.More importantly, it doesn 8217;t hold up experimentally. I 8217;ve asked that questionto a number of people, and none of them suggested the post office. The originalauthor of that puzzle would be waiting in the mailroom alone.
对我来说这个逻辑有点弱。更重要的是，实际上它也不可行。我问了好几个人这个问题，没有一个人建议去邮局等，看来谜题的原作者只能一个人孤零零地等在邮局里了。
Our lost immortals have it tougher, sincethey don 8217;t know anything about the geography of the planet they 8217;re on.
情况对于那两个走失的人来说会更艰难，因为他们对于所处的星球的地理信息一无所知。
Following the coastlines seems like asensible move. Most people live near water, and it 8217;s much faster to searchalong a line than over a plane. If your guess turns out to be wrong, you won 8217;thave wasted much time compared to having searched the interior first.
沿着海岸线走看上去会是一个合理的方案。绝大多数人口住在水源附近，而且沿着一条线寻找要比在一片区域里寻找更加快速。就算你猜错了，和搜寻内陆所花的时间相比，走一遍海岸线也用不了多少时间。
Walking around the average continent wouldtake about five years, based on typical width-to-coastline-length ratios forEarth land masses.
根据地球上大洲宽度和海岸线长度的比值来推算，沿着海岸线走完一整圈大洲需要约5年时间。
Let 8217;s assume you and the other person areon the same continent. If you both walk counterclockwise, you could circleforever without finding each other. That 8217;s no good.
不妨假设你和另一个人都在同一个大洲上，如果你们俩都是逆时针搜寻，很有可能你们永远都遇不到对方。真是糟糕。
A different approach would be to make acomplete circle counterclockwise, then flip a coin. If it comes up heads,circle counterclockwise again. If tails, go clockwise. If you 8217;re both followingthe same algorithm, this would give you a high probability of meeting within afew circuits.
另一种方法是先逆时针走一圈，然后扔硬币决定下一圈的方向，如果正面朝上，那么继续逆时针走；如果反面朝上，那么就顺时针走。如果你们两个人都遵循这种方法，那么在几圈之内，你们就会有很大几率相遇。
The assumption that you 8217;re both using thesame algorithm is probably optimistic. Fortunately, there 8217;s a better solution:Be an ant.
寄希望于你们两个都遵循同样的方法可能有点乐观了，但好在还有一种更好的办法，那就是向蚂蚁学习。