世界不是游乐场，而是思想和利益的战场。

你必须成为你希望在世界上看到的改变。

We must listen to the science—ignoring it will only lead to irreversible damage.

永不放弃，永不屈服。

The truth is rarely pure and never simple.

You cannot hope to build a better world without improving the individuals. To that end, each of us must work for our own improvement and, at the same time, share a general responsibility for all humanity, our particular duty being to aid those to whom we think we can be most useful.

复杂性理论告诉我们，并非所有问题都是平等的；有些问题本质上比其他问题更难。