A contrast or discrepancy between what is said and what is meant or between what happens and what is expected to happen in life and in literature. In verbal irony, characters say the opposite of what they mean. In irony of circumstance or situation, the opposite of what is expected occurs. In dramatic irony, a character speaks in ignorance of a situation or event known to the audience or to the other characters. Flannery O'Connor's short stories employ all these forms of irony, as does Poe's "Cask of Amontillado."
French mathematician & philosopher Henri Poincaré (1854-1912)