Martin E. P. "Marty" Seligman is an American psychologist, educator, and author of self-help books. Since the late 90's, Seligman has been an avid promoter within the scientific community for the field of positive psychology. Wikipedia*
On the C-SPAN Networks:
Martin Seligman has two videos in the C-SPAN Video Library; the first appearance was a 1997 Forum. Most appearances with Cass R. Sunstein (2), Paul Verkuil (2), Kathleen Hall Jamieson (2).