没有人会保护他们不关心的事物，也没有人会关心他们从未经历过的事物。

"The past is never dead. It's not even past."

I went to the woods because I wanted to live deliberately. I wanted to live deep and suck out all the marrow of life. To put to rout all that was not life. And not, when I had come to die, discover that I had not lived.

In teaching history， there should be extensive discussion of personalities who benefited mankind through independence of character and judgement.

Action and knowledge are not obstacles to each other.