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The purpose of abstraction is not to be vague, but to create a new semantic level in which one can be absolutely precise.

There is only one boss. The customer. And he can fire everybody in the company from the chairman on down, simply by spending his money somewhere else.

讀書人雖然有書本知識，但最根本的還是在于把書本知識變為實際行動。

我們不是從祖先那里繼承地球，而是從子孫那里借來的。讓我們把它變得更好。

我能計算天體的運動，卻無法計算人們的瘋狂。