One minus one-half plus one-third, it is all there.

-1/2+1/3，这就是它。

麻省理工公开课 - 固态化学导论课程节选

We are able to talk about the fact that two plus one equals three, but it's not as though we ever come across numbers-- number three itself--anywhere in the empirical world.

我们可与去探讨,二加一等于三的这个事实,但是我们不可能有一天真的碰到数字,在现实世界中碰到个叫"数字三"的东西

耶鲁公开课 - 死亡课程节选

We know it's going around in a circle because if I find the length of this vector, which is the x-square part, plus the y-square part, I just get r square at all times, because sine square plus cosine square is one.

我们之所以知道它做圆周运动,是因为我求出了这个矢量的模长,也就是 x 的平方加上 y 的平方,我就得到了它在任意时刻的模长平方,因为正弦平方加余弦平方始终等于1

耶鲁公开课 - 基础物理课程节选

We all do believe something makes it true that two plus one equals three, but it's not the fact that empirical objects-- We don't do empirical experiments to see whether two plus one equals three.

我们都相信有些东西,使2加1等于3是正确的,但这不是说现实的东西,我们不会在现实中做实验,去看看二加一是不是等于三

耶鲁公开课 - 死亡课程节选