I am delighted to see so many of my colleagues, and it is wonderful to have such a diverse audience. There are few seminars that I go to at Stanford that include psychologists, lawyers, linguists, engineers, and historians. Bringing together such a multidisciplinary group is the mark of the American Academy, and it is one of the things we celebrate here, especially when solving challenges like the one we are going to talk about today will increasingly demand cross-disciplinary collaborations.