In a way, just like Tolstoy's statement about every unhappy marriage being different, every collapsed or endangered society is different -- they all have different details. But nevertheless, there are certain common threads that emerge from these comparisons of past societies that did or did not collapse and threatened societies today. One interesting common thread has to do with, in many cases, the rapidity of collapse after a society reaches its peak. There are many societies
在某种程度上，正如托尔斯泰所言：不幸的家庭各有各的不幸。 同样的道理，每一个崩溃或者行将崩溃的社会都是不同的。 它们的崩溃各有各的原因。尽管如此， 我们还是可以得到一些共识的，通过对比 历史上那些崩溃了和没有崩溃的社会， 这些共识于今也有借鉴意义。在众多社会崩溃的案例中， 可以发现一个有趣的相似点：这个社会发展到其鼎盛时期， 突然急转直下，然后崩溃。历史上，许多社会的发展轨迹