As you get older, there will be a new challenge arising. What you thought you'd accomplished once, maybe the goal post has shifted and it's not what you're pursuing anymore, because you're not interested in that anymore, you know?

I'm very intrigued that in this culture of reality television and celebrity - which is an enormous industry and generates billions and billions of dollars - we're so resourceful.

It was very easy for me to dedicate myself to the care of mothers, help them have healthy babies, help them be healthy, help them in a place where they don't have opportunities. Success breeds the excitement to continue going. It's harder to get out of bed when you've failed.

I have a calling in my soul, if you like, to try to make my life in some way worthwhile. What is the value of my existence?

The future hasn't happened yet and the past is gone. So I think the only moment we have is right here and now, and I try to make the best of those moments, the moments that I'm in.

If you come face to face with some really challenging situations and tragic circumstances - you are going in there with a purpose. You are not going in there as a tourist.

Just having medicine isn't equivalent to medical care. You need the health systems, you need to create the social framework so that people feel safe.