translation.en: With the invention of writing, you start getting cities. This is blurry. I kind of like that because it makes it look like a one-celled organism and reminds you how many levels organic organization has already moved through to get to this point. And then you get to, you know, you get empires.
translation.zh: 随着书写的发明，城市出现了。这个关系看上去有点牵强。但是我很喜欢， 整个过程就像刚才所讲的单细胞组织的进化过程， 有机体经过层层演化， 才成了今天的样子。接下来的，你们一定猜到，是帝国。