Robert, you and I have been talking about agnotology—the structure of impressed ignorance—for a long time now, or certainly since the time we were graduate students. Over the years, you have been focused quite rightly on the vast industrial apparatus that produces nonknowledge, especially in the spheres of the environment and health. I've been engaged with government secrecy—the excision of knowledge imposed on society, especially in matters of national security. Both of us see the intersection of politics and knowledge, or should I say nonknowledge, as an essential area of inquiry. Let's begin with your side: Could you say a little bit about how you got interested in what we don't know?