He who refuses to do arithmetic is doomed to talk nonsense.

I've been through it all, baby, I'm mother courage.

曾经尝试过，曾经失败过。没关系。再试一次。再失败一次。失败得更好。

The concept of infinity is not just a mathematical abstraction, but a physical reality.

膨胀的概念是宇宙在其最早的时刻经历了一段极其迅速的扩张期。

学习本质上是刺激-反应连接的问题。