The authors discussed their book, Generations: The History of America's Future, 1584 to 2069. The book is about the effect of generational trends on history and American culture. The authors sort Americans into 18 generations, and then distinguish among four life cycle types. Each generation seems to take on one of the following characteristics: idealist (moralistic), reactive (pragmatic), civic (selfless), or adaptive (compromiser). The past, they said, showed there are often significant parallels between the "new" movements of each generation. "American society had pulsed to rhythms both within the family and within the world at large." They postulate that the four life cycle types can be used both to explain history and predict the future patterns of American culture. Their vision of the future is based on their study of America's past influences. They call this book the "full story of America around the 18 generations of our history."