A mystery

That letter is a mystery. It sits in a little pocket in my desk and, from time to time, I reread it to see if it will make sense to me. The last time I read it, I began laughing uncontrollably. It is not a particularly funny letter, and I am not sure whether I laughed out of joy or incredulity. It is a marvel, impossible, absurd, a dream. A work of art and a feat of artifice. So vivid, beguiling, neat. I can't decide if it's evidence or exoneration. Is it true? Is it false? A red herring? A clue? Who wrote it? Was it you? Who were you? Who might you be? For whom did you write it and why did you send it to me? You write with such clarity and purpose. But I've never been sure what you mean.