人生是一次性的旅行。

剑鞘保护剑的锋利，自己却满足於它自己的迟钝。

The future of life on Earth depends on our ability to take action. Many individuals are doing what they can, but real success can only come if there is a change in our societies and our economics and in our politics.

最好的技术是能解决实际问题的技术。