一个人，如果不是他们留下的痕迹，又是什么呢？
数学的美在于它允许我们抽象出现实世界的复杂性，专注于基本原则。
外部世界的旅程可能有一百万步;内心世界的旅程只有一步:当下正在迈出的这一步。
The best stories are those that resonate with both children and adults.
The reality is: sometimes you lose. And you're never too good to lose. You're never too big to lose. You're never too smart to lose. It happens.
Energy poverty is one of the greatest challenges of our time. Access to affordable energy should be a right, not a privilege.
