incongruity theory posits that comedy arises from a mismatch—specifically, a mismatch between expectation and actuality. According to this theory, funny situations begin with attachment to a belief, whether that attachment is conscious or unconscious, fleeting or deep, sincerely held or deliberately planted by a comedian or a prankster. That belief is then violated, producing surprise, confusion, and a replacement belief—and also producing, along the way, enjoyment and laughter. In other words, the structure of humor is—give or take a little pleasure—the structure of error.
