What is the theme of William Wilson?

The theme of "William Wilson" is the destructive power of guilt and the inescapable nature of one's past. The story explores the psychological deterioration of the main character, William Wilson, as he is haunted by a mysterious doppelgänger who shares his name. This doppelgänger represents the protagonist's repressed guilt and conscience, constantly reminding him of his past misdeeds and preventing him from escaping his own moral failings. The theme of the story cautions against evading one's responsibilities and the consequences of one's actions, as the protagonist ultimately faces the consequences of his past choices and succumbs to the guilt that has been consuming him.