The Better Angels of Our Nature: Why Violence Has Declined

This book is absolutely wonderful and sheds a light of optimism on the past and future of humanity. The first chapters are devoted to arguing Mr Pinker's point with the numbers while the remaining one describe the underlining psychological reasons that support such trends. The language used is clear which makes this book very accessible even for non-specialists. The only thing that annoyed me a bit was that sometimes all the data is a bit confusing !