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The best way to learn mathematics is to do mathematics.

We are all searching for something, whether we admit it or not, and that search defines us.

"The best books are the ones that leave you a little different than when you started."

追根究底，我們最基本的共同聯系是我們都生活在這個小型行星。我們都呼吸著相同的空氣。我們都珍惜我們孩子的未來。我們都是凡人。

In one of the stars I shall be living. In one of them I shall be laughing. And so it will be as if all the stars were laughing, when you look at the sky at night… You-only you-will have stars that can laugh…