To see the hierarchy in this mechanism, consider that by perceiving just a few letters, you can predict the word; by looking at a few words, you can predict what the sentence means, or even the paragraph. In fact, right now you must be guessing where it is that I am going with this entire commentary.
要想理解这一机制中的层级性，想象一下，你可以在看到几个字母后便猜测单词；在看到几个单词后，你可以预测出句子甚至段落的意思。层级性让你能够理解含义，不管信息是通过阅读还是聆听进入你的大脑的。因此，大脑是一部归纳机器，根据寻找诸多不同层次的现在和过去的相似性推测未来。