The world is very disparate, in terms of the US using the most energy per person, and then the other rich countries - Europe, Japan, New Zealand - using about half of what we do, and then the world average being about a fifth of what we use, with China just now surpassing the world average.

We'll have infinite bandwidth in a decade's time.

There's nobody getting rich writing software that I know of.

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.

My son likes to go see mines and electric plants, or the Large Hadron Collider, and we've had a chance to see a lot of interesting stuff.

Online education is pretty special for two reasons. One is that you can get the very best lecture in the world and wherever you are, whenever you want, you can connect to that lecture. The other is this interactivity, where if you know a topic, you can kind of skip over it. Or if you're confused about it, [the area] where you're confused can be analyzed by software.

Students deserve great teachers. And teachers deserve the support they need to become great.