The theme of the short story “William Wilson” by Edgar Allan Poe is inner conflict and duality.
William Wilson is constantly caught between his tendency to engage in immoral acts, and his moral conscience, which tries to prevent that. Throughout the story, his evil side appears to gain more ground, but neither side entirely gives in. It is the eternal battle between good and evil, except it takes place in William’s mind, and its purpose is to influence William’s behavior.
The title of the story also suggests this. It is the story of “William Wilson”, and his struggle with himself, not of William Wilson and a mysterious stranger.
William’s double appears guided by a moral entity which is higher than himself, and even his own will: “ ‘Gentlemen, I am here only to do my duty’ ” (p. 17, p. 9)
He also appears whenever William feels remorse or has second thoughts about his actions. F...