It is important to remember that Hawthorne was considered a "Dark Romantic" rather than just a Romantic author. The Dark Romantics, as they were named, consisted of authors such as Hawthorne, Poe and Melville. They were considered as almost anti-Transcendentalists because the way they looked at the world was so different to the optimistic views of Emerson and authors of his ilk. However, the work of these Dark Romantics did actually have much in common with the Transcendentalists. Both groups valued intuition over logic and reason. Both groups saw signs and symbols in all events. Where they differ is that the Dark Romantics, when considering nature, placed an emphasis on Original Sin, its sense of the innate wickedness of human beings, and its notions of predestination.
The writings of Hawthorne, then, as in "The Minsiter's Black Veil," explored the conflict between good and evil and the psychological effects of guilt and sin. Behind the pasteboard masks of social respectability, the Dark Romantics saw the blankness and the horror of evil. It is this idea that Hawthorne deliberately plays with in this story as he forces the villagers to confront the hidden sin within themselves through the symbol of Mr. Hooper wearing an outer sign of his own secret sin.