“William Wilson” explores the theme of the doppelganger, or ghostly double. Poe’s inspiration for the story was the horror one feels when discovering another person shares your name. In this story, this horror is magnified by the exact identical appearance, age, and manner of the double. The horror comes from a feeling of lost individuality and a self-doubt; again, these feelings are magnified in “William Wilson” through the exaggerated effects of gothic fiction.
The narrator masks his identity from the reader because he doesn’t want to face it himself.
The narrator fully understands his own dual identity.