相关系数的可能误差不是一个固定的量，而是取决于样本的大小。

我不想和以前一样好，我想比以前更好。

The only constant is change, continuing change, inevitable change, that is the dominant factor in society today. No sensible decision can be made any longer without taking into account not only the world as it is, but the world as it will be.

勇气不是没有恐惧，而是战胜恐惧。

最终，生存是关于生存的意志。它是关于人类精神的。