We live in anxious times. In Steven Pinker's 2011 book The Better Angels of Our Nature: Why Violence Has Declined, the Harvard University psychologist argues humans are now living in the most peaceful era in the history of our species. Still, we are anxious. And it's hard not to be. In February, it was the Parkland shooting. In April, the IHOP shooting and the harrowing Southwest airliner that broke apart as it was bound for Dallas. Last week, our neighbors in Santa Fe, T