Supernatural, redemption, impact of society. “Solitary” means alone, but not necessarily by choice, showing something forced him to be lonely. “Oyster” symbolises capitalism as in an oyster there’s a pearl - representing Scrooge - but the Scrooge we initially see has been encapsulated by the oyster because of capitalism. As the novel progresses, the Ghosts crack at his oyster to reveal the soft man that his nature really is. The quote foreshadows that there is a chance that Scrooge will change.