"We used to canonize our heroes," Oscar Wilde wrote. "The modern method is to vulgarize them. Cheap editions of great books may be delightful, but cheap editions of great men are absolutely detestable." Since Wilde's condemnation of modern biography, the genre would appear to have accelerated its descent into bad taste. As Carl Rollyson points out, writers as various as Rebecca West, Ted Hughes, and Joyce Carol Oates have deplored biographers' tendency...