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Every problem in mathematics is an opportunity to learn something new.

Anybody can make history. Only a great man can write it.

Entanglement is not just a curious feature of quantum mechanics - it is the essential feature.

The most dangerous art is the kind that makes you think.

每一次挑戰都是偽裝的機遇。

Buying tools: Start by buying the absolute cheapest tools you can find. Upgrade the ones you use a lot. If you wind up using some tool for a job， buy the very best you can afford.