The Signal-Man

We do not know anything about the narrator’s past, yet we learn many details about the signal man’s past and present. Why does the narrator not provide any background regarding himself? How does this absence inform the story?

The narrator suggests a connection between the first apparition and the train driver, but what are we to make of this connection? Is it possible to reach any definite conclusion about the apparitions and their reality? Does their reality (or unreality) affect the story’s meaning in any way?

The signal man never expects that the ghost’s warning could concern his own life. Why? Is this a result of him being a poor reader? A result of his selflessness? Are the two connected?