Tolkien got the main symbols in The Hobbit from Richard Wagner's Ring cycle, but he was testy and sensitive whenever Wagner's name was mentioned. The problem was Wagner's anti-Semitism. The English had a long history of philo-Semitism that did not mesh with Wagner's views, leading to an artistic conflict that Tolkien could not resolve, and ultimately to an incoherent book. In purging Wagner's symbols of their anti-Semitism, Tolkien purged them of...