The Upswing: How America Came Together a Century Ago and How We Can Do It Again, by Robert D. Putnam and Shaylyn Romney Garrett (Simon & Schuster, $32.50)

In a sweeping overview of more than a century of history, drawing on his inimitable combination of statistical analysis and storytelling, Robert Putnam analyzes a remarkable confluence of trends that brought us from an “I” society to a “We” society and then back again.

Professor Robert Putnam and Shaylyn Romney Garrett discussed their new book, “The Upswing: How America Came Together a Century Ago and How We Can Do It Again,” at a Kennedy School event.