I'm going to start with the simplest example and slowly add on bells and whistles and make it more and more complicated.

我会从最简单的例子开始,逐渐增加难度,让问题越来越复杂

耶鲁公开课 - 基础物理课程节选

We want to do that in the simplest context, then we can make the example more and more complicated, but the phenomenon will be the same.

我们想举一个最简单的情景,随后我们可以再看一下更复杂的情况,但是万变不离其宗

耶鲁公开课 - 基础物理课程节选