he is a professor at emory university. david anderson. he studies the neural circuits that control fear and anxiety. he is a professor of neuroscience at cal tech and a howard hughes medical investigator. and once again, my co-host is dr. eric kandel. as you know by now, he's a nobel laureate and professor at columbia university and a howard hughes medical investigator. he is, as you know, the mastermind behind this program and once again i'm pleased to have him here at this table to tell me what we're going to talk about this evening. welcome. >> thank you. pleasure to be here. >> rose: where are we going tonight? >> we're going to discuss emotions some more. emotions are feeling states that enrich our mental life. they lead us to seek out pleasure and to avoid pain and tonight we're going to begin by discussing fear and anxiety states and then go on to discuss aggression. >> rose: why are they important to our survival? >> in the presence of a danger, the most important thing is to get away, to freeze, to decide, you know, what sort of