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Mathematics is not a deductive science—that's a cliché. When you try to prove a theorem, you don't just list the hypotheses and then start to reason. What you do is trial and error, experimentation, guesswork.

教育是最有力的武器，可以改變世界。

The world is not a problem to be solved; it's a living being to which we belong.

Stay true to yourself and never let what somebody else says distract you from your goals.

We don't inherit the ocean from our ancestors; we borrow it from our children.

忠于自己和你的藝術。