Social and political scientist Robert Putnam has long warned of the problems America’s increasing social isolation has caused — most famously, in his 2000 book “Bowling Alone.” In his latest book, “The Upswing,” along with co-author Shaylyn Romney Garrett, he argues that history provides a model for us to overcome our current self-centered nature, and once again focus on the collective good. The last gilded age, at the end of the 19th century, “was a time of great inequality, great polarization, great social isolation [and] great cultural narcissism,” according to Putnam. But what Garrett describes as the “moral reckoning” that followed put the nation back on the path toward a stronger and more equal society — providing a roadmap that could also help us today. Putnam and Garrett joined Jim Braude to discuss.