I think, sometimes, that I'm going nuts, and that perhaps there is something good about blocking clean water for those who have none, making sure that illiterate children remain so, and preventing the resuscitation of the public health sector in the country most in need of it. Lunacy is what it is.

The world is full of miserable places. One way of living comfortably is not to think about them or, when you do, to send money

But as for activism, my parents did what they could, given the constraints, but were never involved in the causes I think of when I think of activists.

We've taken on the major health problems of the poorest - tuberculosis, maternal mortality, AIDS, malaria - in four countries. We've scored some victories in the sense that we've cured or treated thousands and changed the discourse about what is possible.

I think that looking forward it's easy to imagine more constructive help for Haiti.

The poorest parts of the world are by and large the places in which one can best view the worst of medicine and not because doctors in these countries have different ideas about what constitutes modern medicine. It's the system and its limitations that are to blame.

If you look just at the decades after 1934, you know it's hard to point to really inspired and positive support from outside of Haiti, to Haiti, and much easier to point to either small-minded or downright mean-spirited policies.