Since the publication of The Lord of the Rings by J. R. R. Tolkien, a wealth of secondary literature has been published discussing the literary themes and archetypes present in the story. Tolkien also wrote about the themes of his book in letters to friends, family and fans, and also in the book itself. In his Foreword to the Second Edition, Tolkien said that he "disliked allegory in all its forms" (using the word applicability instead), and told those claiming the story was a metaphor for World War II to remember that he had lost "all but one" of his close friends in World War I.