And I hope you will come back here to Harvard 30 years from now and reflect on what you have done with your talent and your energy. I hope you will judge yourselves not on your professional accomplishments alone, but also on how well you have addressed the world's deepest inequities…on how well you treated people a world away who have nothing in common with you but their humanity.

创新是开启可持续能源未来的关键。

大众对大小事都有无尽的求知欲---除了真正值得知道的事例之外。