Going out in the field, it's always enlightening to see what's working and what's not and to sit down and talk - I was with young girls in south Africa - understanding why our tools for prevention aren't being adopted, and what way may need to invent to help protect them.

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.

Success is a lousy teacher. It seduces smart people into thinking they can't lose.

Software substitution, whether it's for drivers or waiters or nurses ... it's progressing. ... Technology over time will reduce demand for jobs, particularly at the lower end of skill set. ... 20 years from now, labor demand for lots of skill sets will be substantially lower. I don’t think people have that in their mental model.

We all learn best in our own ways. Some people do better studying one subject at a time, while some do better studying three things at once. Some people do best studying in structured, linear way, while others do best jumping around, surrounding a subject rather than traversing it. Some people prefer to learn by manipulating models, and others by reading.

Philanthropy is fun and fulfilling.

Africa is on the rise.