The End of War is one of a few books that have come out recently that argues that war is on the way out and also advocates for its dismissal. Horgan’s book is primarily focused on making the case that war is a choice human societies make. It is not something inherent to human nature or written into our biology. For Horgan war is a “cultural contagion” which can infest societies much like a virus but as he points out it can also be resisted. I would say Horgan is cautiously optimistic that war can be eradicated, maybe not in his lifetime, but at some point in the future. Since he is a science journalist much of the book consists of him wading through the biological and anthropological evidence that war is somehow ingrained in human nature and he comes away finding this evidence unconvincing. This leads him to review some of (but not very comprehensively) the psychological, social and political research on war and conflict. Here is where he establishes his thesis of conflict as a cultural contagion. The most interesting aspect of the book is the end where Horgan makes a plea for us to continue to believe in free will because then we as humanity are still responsible for eradicating war. To reduce war to determinative biological factors, or vague ideas of human nature, would remove our responsibility to work for peace according to the author, and therefore those ideas must be resisted. The books is as much a call to arms (pun intended) as a book of reportage and for that I find it a refreshing and exciting read.