Insight is the understanding of a specific cause and effect within a particular context. The term insight can have several related meanings: a piece of information the act or result of understanding the inner nature of things or of seeing intuitively (called noesis in Greek) an introspection the power of acute observation and deduction, discernment, and perception, called intellection or noesis An understanding of cause and effect based on the identification of relationships and behaviors within a model, context, or scenario (see artificial intelligence) An insight that manifests itself suddenly, such as understanding how to solve a difficult problem, is sometimes called by the German word Aha-Erlebnis. The term was coined by the German psychologist and theoretical linguist Karl Bühler. It is also known as an epiphany, eureka moment or (for cross word solvers) the penny dropping moment (PDM). Sudden sickening realisations often identify a problem rather than solving it, so Uh-oh rather than Aha moments are further seen in negative insight. A further example of negative insight is chagrin which is annoyance at the obviousness of a solution missed up until the point of insight, an example of this being the Homer Simpson's catchphrase exclamation, D'oh!. Psychology In psychology, insight occurs when a solution to a problem presents itself quickly and without warning. It is the sudden discovery of the correct solution following incorrect attempts based on trial and error. Solutions via insight have been proven to be more accurate than non-insight solutions. Insight was first studied by Gestalt psychology, in the early part of the 20th century, during the search for an alternative to associationism and the associationistic view of learning. Some proposed potential mechanisms for insight include: suddenly seeing the problem in a new way, connecting the problem to another relevant problem/solution pair, releasing past experiences that are blocking the solution, or seeing problem in a larger, coherent context. Classic methods Generally, methodological approaches to the study of insight in the laboratory involve presenting participants with problems and puzzles that cannot be solved in a conventional or logical manner. Problems of insight commonly fall into three types. Breaking functional fixedness The first type of problem forces participants to use objects in a way they are not accustomed to (thus, breaking their functional fixedness), like the "Duncker candle problem". In the "Duncker candle problem", individuals are given matches and a box of tacks and asked to find a