Aryeh Neier: The topic of this session is "What We Have Learned about Limiting Knowledge in a Democracy," and it says we should discuss "how should we proceed and where should lines be drawn?" I'm going to conduct a conversation in which I will focus on this question of limits. The panel is very distinguished, very diverse, and I think we ought to be able to anticipate a diversity of views. All of our speakers are people who promote freedom of (...) information, but I am going to begin by asking them to reverse that role this evening. All of them, I assume, have certain limits they would impose on the availability of knowledge, and I'd like to know what those limits are, then see if there are some common threads or themes that we can extract from what they have to say. (shrink)