Who is Ben Marcus from The Age of Wire and String and what is their importance?

Ben Marcus is the author and the narrator, as well as a false map, scroll, caul, or parchment, a garment, and the "antiperson." In other words, Ben Marcus is a decidedly elusive and changeable character in this book. At one point, the author describes "The Ben Marcus" as, "a fitful chart in the darkness," which, when properly decoded, indicates only that we should destroy it and look elsewhere for instruction.