Jeffrey Sachs speaks with Christopher Blattman, author of Why We Fight: The Roots of War and the Paths to Peace.

In this episode, Jeffrey Sachs and Professor Christopher Blattman explore the dynamics of war and peace: how communities resolve conflicts, and why such efforts sometimes fail, leading to war.  Prof.  Blattman argues that violence is not the norm; that there are five reasons why wars break out; and how peacemakers can draw on these reasons to prevent and stop wars.