He published his only novel more than fifty years ago. He has hardly been seen or heard from since 1965. Most writers fitting such a description are long forgotten, but if the novel is The Catcher in the Rye and the writer is J. D. Salinger . . . well, he's the stuff of legends, the most famously reclusive writer of the twentieth century. If you could write to him, what would you say? Salinger continues to maintain his silence, but Holden...