Cognitive dissonance is a psychological phenomenon that occurs when an individual experiences mental discomfort due to conflicting beliefs, values or ideas. This uneasy feeling often leads people to take steps to reduce the inconsistency and restore their sense of balance. The theory of cognitive dissonance was first proposed by Leon Festinger in 1957, who suggested that individuals are motivated to maintain consistency between their beliefs and actions, and will go to great lengths to achieve this equilibrium. For example, if someone believes strongly in the importance of exercise but fails to engage in regular physical activity, they may experience dissonance. To resolve this inconsistency, they might start a new workout routine or justify their lack of exercise by convincing themselves that they have an unusual physiology or other mitigating factors. Cognitive dissonance can also arise from social situations where individuals feel conflicted between the demands of different groups or roles they occupy. Overall, cognitive dissonance is a powerful force that shapes human behavior and decision-making in various contexts.