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在數學中，提出問題的藝術必須比解決問題更有價值。

"A book is a conversation between the writer and the reader across time."

The best fertilizer is a farmer's knowledge mixed with nature's wisdom.

Life is far too important a thing ever to talk seriously about it.

Psychology must be a science of facts, not theories.

The act of writing is an act of optimism. You would not take the trouble to do it if you felt it didn't matter.

You have to be willing to fail, to be wrong, to look foolish.

I don't believe in luck. I believe in preparation meeting opportunity.