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True sustainability means meeting today's needs without compromising tomorrow's possibilities.

The beauty of physics lies not in having all the answers, but in asking better questions.

I think that's one of the most important things in life: to feel good about yourself.

關于神，我無法知道他們是否存在，也無法知道他們是什么樣子的。許多事情阻礙了知識，包括主題的晦澀和人類生命的短暫。

人不是環境的產物；環境是人的產物。

Children have real understanding only of that which they invent themselves, and each time that we try to teach them something too quickly, we keep them from reinventing it themselves.

即使追求效率，質量也絕不能妥協。

Courage is the price that life exacts for granting peace.