你有没有发现流行文化总会刮起一阵阵的“复古风”和“怀旧风”？你有没有总结过这阵风具有什么样的规律呢？Adam Gopnik发在《纽约客》的一篇文章就为我们揭开了美国流行文化的“四十年黄金定律”（The Golden Forty-Year Rule）。

The prime site of nostalgia is always whatever happened, or is thought to have happened, in the decade between forty and fifty years past.
人们怀旧的主要场景一般都是那些发生或是我们以为发生在四五十年之前的情景。

What drives the cycle isn’t, in the first instance, the people watching and listening; it’s the producers who help create and nurture the preferred past and then push their work on the audience.
主导这种“怀旧周期”的并不是流行文化的受众，而是信息的生产者。这些生产者将他们自己所向往的过去重新创造发扬光大，并把这些成果推向广大的受众。

Though pop culture is most often performed by the young, the directors and programmers and gatekeepers—the suits who control and create its conditions, who make the calls and choose the players—are, and always have been, largely forty-somethings.
尽管流行文化通常是在年轻人身上体现出来的，但流行文化的指导者、编排者和把关者——包括服装师、场景设计师、联络人和选择演员的工作人员——基本上都是四十岁左右的人。

Forty years past is the potently fascinating time just as we arrived, when our parents were youthful and in love, the Edenic period preceding the fallen state recorded in our actual memories.
四十年前他们刚到这个世界上，那时父母们还年轻、还在享受爱情。比起后来的记忆中堕落的状态，那是一段伊甸园一般的美好时光。

The forty-year rule is, of course, not immutable, and its cycle carries epicycles within it: the twenty-year cycle, for instance, by which the forty-somethings recall their teen-age years. But it is the forty-years-on reproduction of a thing that most often proves more concentrated and powerful than the original.
所谓的“四十年黄金定律”当然不是铁打不变的，例如四十年的大周期中还包含着一个二十年的小周期，即四十岁左右的人开始回忆他们的少年岁月。不过事实证明还是四十年之后的复制更有力量。

And so, if we can hang on, it will be in the twenty-fifties that the manners and meanings of the Obama era will be truly revealed: only then will we know our own essence.
因此，如果我们再等一等，我们这个时代的习惯和含义就会在2050年被真正的揭示出来：只有到了那时我们才能够了解我们自己的本质。