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Sustainability is not an option; it's a responsibility we owe to future generations.

History is not the past. It is the present. We carry our history with us. We are our history.

What's terrible is to pretend that second-rate is first-rate. To pretend that you don't need love when you do; or you like your work when you know quite well you're capable of better.

物理學的美在于它能夠用簡單的定律解釋復雜的事物。