幸福取决于内心，而非外界。

Mental activity is always directed toward some end.

"The challenge of biography isn't finding the facts - it's finding the meaning behind them."

数学教会我们逻辑思考并系统地处理问题。

历史的伤痕并非总是可见的，但它们始终存在。

意识的元素是心理生活不可再分的事实。