一个人若不付出一些无知的代价，就永远不会幸福。
最好的科学是双手弄脏而头脑清醒时完成的。
"Humor is the great thing, the saving thing. The minute it crops up, all our irritations and resentments slip away and a sunny spirit takes their place."
Education does not take root in the soul unless it goes deep.
Life is too short to hold grudges.