If you live in two dimensions or more, you've got to use vectors to describe most things.

如果你要考虑二维或二维以上的问题,大多数情况下需要用矢量来描述

耶鲁公开课 - 基础物理课程节选

In fact, I'm going to use only two dimensions for most of the time because the difference between one dimension and two is very great.

实际上,大多数时候我只考虑二维的情况,因为一维和二维的差别很大

耶鲁公开课 - 基础物理课程节选