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"In mathematics, you don't understand things. You just get used to them."

“孟母三遷”的故事我們都不陌生，環境對人的成長和身心修養起著重要作用。人際交往的圈子也是重要的環境，對自己身邊的環境要慎重選擇，不隨不良環境而墮落。

心理學理論的價值是由其實用性衡量的。

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.

你不能以貌取人，但你可以通過第一章來判斷一本書。