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The test of a first-rate intelligence is the ability to hold two opposed ideas in mind at the same time and still retain the ability to function.

Understanding black holes is understanding the fabric of the universe itself.

追求知識是一段沒有終點的旅程，每一個發現都是踏入未知的一步。

The most dangerous phrase in business is 'We've always done it this way.'

促使人們傾向于和平的激情是對死亡的恐懼，對舒適生活必需品的渴望，以及通過自己的努力獲得這些的希望。