Related to the subject of declining violence: http://www.businessinsider.com/mark-zuckerberg-bill-gates-recommend-steven-pinker-book-better-angels-2015-2 http:/

Related to the subject of declining violence: http://www.businessinsider.com/mark-zuckerberg-bill-gates-recommend-steven-pinker-book-better-angels-2015-2 http://www.businessinsider.com/mark-zuckerberg-bill-gates-re...