How does Chillingworth respond to Hester's plea that he change his course of action?

Hester then tells Chillingworth that she plans to reveal his true identity to Dimmesdale. He is unmoved by this, telling her that nothing he or she does can alter the way things now stand. She pleads with Chillingworth to pardon Dimmesdale for what happened so that he can let go of his revenge. Chillingworth replies, "Let the black flower blossom as it may."