You can't get people excited unless you can help them see and feel the impact. And how you do that - is a complex question.
Still, I'm optimistic. Yes, inequity has been with us forever, but the new tools we have to cut through complexity have not been with us forever. They are new - they can help us make the most of our caring - and that's why the future can be different from the past.
The defining and ongoing innovations of this age - biotechnology, the computer, the Internet - give us a chance we've never had before to end extreme poverty and end death from preventable disease.
Sixty years ago, George Marshall came to this commencement and announced a plan to assist the nations of post-war Europe. He said:
"I think one difficulty is that the problem is one of such enormous complexity that the very mass of facts presented to the public by press and radio make it exceedingly difficult for the man in the street to reach a clear appraisement of the situation. It is virtually impossible at this distance to grasp at all the real significance of the situation."
Thirty years after Marshall made his address, as my class graduated without me, technology was emerging that would make the world smaller, more open, more visible, less distant.
The emergence of low-cost personal computers gave rise to a powerful network that has transformed opportunities for learning and communicating.
The magical thing about this network is not just that it collapses distance and makes everyone your neighbor. It also dramatically increases the number of brilliant minds we can have working together on the same problem - and that scales up the rate of innovation to a staggering degree.
At the same time, for every person in the world who has access to this technology, five people don't.
That means many creative minds are left out of this discussion — smart people with practical intelligence and relevant experience who don't have the technology to hone their talents or contribute their ideas to the world.