What I would say about this one, cause it's most complicated, I would say, in the history of humanity.

我会说，因为,是非常复杂的，我会说，是整个人类史上最复杂的。

普林斯顿公开课 - 人性课程节选

Now the word theory has a very complicated etymological history that I won't trouble you with.

理论这个词的词源非常复杂,你们不需要了解。

耶鲁公开课 - 文学理论导论课程节选