Only on the "CBS This Morning" podcast, best-selling author Steven Pinker joins CBS This Morning co-host John Dickerson about his new book, "Enlightenment Now: The Case for Reason, Science, Humanism and Progress." Pinker explains why we need to take a step back from the gloom and doom of the daily headlines and look at the data of how progress has improved life not just in America, but worldwide. Pinker attributes that progress to the Enlightenment.