you can't take Nagel's perspective seriously. But for some reason I kept thinking he is very very similar to the main character in Hunger. I even allowed my imagination to presume he is the same character who after landing on the ship and leaving Kristina in Hunger , he then harbored in another small city in "Mysteries" and started another life.
one can allow himself to go on with his imagination when he reads an amazing masterpiece that can peneterate deep down in soul and mind and even imagine that the fictional characters are real and their destiny didn't stop in the pages of the novel.
I loved Mysteries, and I even loved the unexpected ending which came as a suriprise at the end.. I wanted to know a lot of answers, but I guess this is the intent of the author, to leave you puzzled with unanswered questions, maybe to create the desired effect, or to selfishly keep all the answers fir himself, it is his book at thend !. Maybe the answers were never known even to the writer, when he wrote his book and imagined all of the characters and Jove inspired him to depict such mania and rationality in the most creative style. I love Knut Hamsun.