Chip Somodevilla/Getty Images Bill Gates' new favorite book is "Enlightenment Now" by Steven Pinker. Pinker's book makes a case that rational thought and scientific inquiry are constantly improving the world. We're living in the safest era of human history, according to Pinker's analysis. Bill Gates' favorite author recently published a new book — and Gates has already called it his "favorite book of all time," on his blog.