A highlight of Matthew D’Ancona’s short book, Post-Truth: The New War on Truth and How to Fight Back (2017), published by Edbury Press, is the telling anecdote. And D’Anconna has many to tell. In the book’s preface, the writer relates how he was saved from a potentially life-threatening perforated ulcer and abdominal sepsis sustained in September 2016. D’Ancona, a political columnist with The Guardian and former...