Some symbolism in The Scarlet Letter is obvious--for example, that giant 'A' on Hester's chest. Other examples aren't as easily understood...until now.
Some of the symbols in The Scarlet Letter can be hard to keep track of, insomuch that symbols in the novel change as the novel progresses, being always open to interpretation. The following emphasize important aspects of the novel.
The Scarlet Letter - Initially affixed as a punishment for adultery, the scarlet letter means different things as the novel progresses. At first it means adultery. Then it means able. Its meaning then becomes indefinite. It is eventually looked on as a symbol of strength. The townspeople regard it as an object of scorn. Hester regards it as a constant reminder of her sin. Outsiders see it as a novelty, and some Native Americans presume it's a distinguishing mark for someone of status.
The Mark on Dimmesdale's Chest - Dimmesdale's mark is an outward manifestation of inward corruption and hypocrisy. Like his sin it remains secret from the public but is known to him and to Chillingworth, who symbolizes the devil.
Pearl - More than a character, Pearl is a living symbol of Hester's sin, a constant reminder of her infidelity. She pesters not only Hester, but Dimmesdale, whom she recognizes as being guilty of the same crime as her mother.
The Rosebush at the Prison Door - The reader is greeted immediately with the symbol of a rosebush in an otherwise dreary setting. The narrator provides several possible interpretations of the anomalous rosebush, yet, as with other symbols in the book, assigns no singular meaning to it. Possible interpretations include the triumph of nature over man made contrivances, a foreshadowing of Hester's blossoming under harsh Puritan rule, or the triumph of the individual against society, a common theme in American Romanticism.
Roger Chillingworth - Hester's husband is the lone symbol in the novel that can be interpreted narrowly. He represents evil. His sole purpose in life becomes revenge.
The Meteor - As Dimmesdale stands on the scaffold in chapter 12, a meteor flashes an 'A' across the sky. Dimmesdale feels it symbolizes that he should wear the 'A' on his chest. The townspeople believe it means angel in honor of Governor Winthrop who had died. The differing interpretations reflect the belief that personal experience filters symbolic meaning for each individual.
What are some other symbols you noticed while reading the novel?