What it says about Mark Zuckerburg: "It's a timely book about how and why violence has steadily decreased throughout our history, and how we can continue this trend," Zuckerberg wrote when announcing the second title. "Recent events might make it seem like violence and terrorism are more common than ever, so it's worth understanding that all violence -- even terrorism -- is actually decreasing over time. If we understand how we are achieving this, we can continue our path towards peace." Mark Zuckerberg - future Nobel Peace Prize winner?