第一代杂种的同一性，第二代的不相似性，是精确观察者无法忽视的事实。

The causal approach is about understanding the mechanisms that generate the data.

当你经历生活给我们所有人带来的挫折时，改变你对自己说的那些破坏性的话是乐观的核心技能。

I've been waiting more than 30 years to say this: "Dad, I always told you I'd come back and get my degree." I want to thank Harvard for this timely honor. I'll be changing my job next year…and it will be nice to finally have a college degree on my resume.

衡量一个人的真正标准是他如何对待那些对他绝对没有好处的人。