Gestalt theory proposes that the whole is greater than the sum of its parts. It emphasizes that humans naturally perceive complete patterns and forms even when presented with incomplete information. Some key Gestalt principles include figure/ground perception, proximity, similarity, continuity, closure and the law of prägnanz. These principles help explain how humans are able to quickly assess surroundings and solve problems through insight. Gestalt theory challenged earlier structuralist views that knowledge comes only from breaking experiences down into individual elements through sensation and introspection.