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Confidence is the most beautiful thing you can possess.

The farmer is the only man in our economy who buys everything at retail, sells everything at wholesale, and pays the freight both ways.

"The great secret that all old people share is that you really haven't changed in seventy or eighty years. Your body changes, but you don't change at all. And that, of course, causes great confusion."

量子力學(xué)的本質(zhì)在于它提供了一個數(shù)學(xué)框架，用于描述原子和亞原子粒子的行為。