In low-income countries, the main problems you have is infectious diseases.

If I only had two dollars left I would spend one dollar on PR.

We all have the chance to create a world where extreme poverty is the exception rather than the rule.

When we face a choice between adding features and resolving security issues, we need to choose security.

The general idea of the rich helping the poor, I think, is important. That your sense of justice says, why should rich kids - who barely get these diseases and almost never die of them - why should they get the vaccines, when poor kids, who actually do die from these diseases, don't get those things? It's an unbelievable inequity that there isn't that access.

Software is inherently complicated. If you say to somebody I want an airline reservation system, to really say what you want in terms of overbooking and fares, and different airlines communicating with each or schedule changes, it's immensely complex. And so you can't write a program that's any simpler than that full specification.

Vaccination is one of the easiest things on the way to development. It's much easier than roads and a great education system. It's very basic. It's one of the first things you want to get right.