Paul Kennedy; Joel Schumacher; Steven Weinberg

Paul Kennedy, a Yale University history professor specializing in international relations, discusses his research into critical world issues, as presented in his book, "Preparing for the Twenty-First Century." Filmmaker Joel Schumacher talks about his latest film, "Falling Down." Steven Weinberg, a Nobel laureate in physics, presents his book, "Dreams of a Final Theory: The Search for Nature's Final Laws."