For every dollar you spend purchasing something substantial， expect to pay a dollar in repairs， maintenance， or disposal by the end of its life.

Innovation in energy must be balanced with responsibility—progress cannot come at the expense of the planet.

I've been waiting more than 30 years to say this: "Dad, I always told you I'd come back and get my degree." I want to thank Harvard for this timely honor. I'll be changing my job next year…and it will be nice to finally have a college degree on my resume.

合理储蓄，积极投资。学习你所应学。