The Lucas Critique is an economic theory proposed by economist Robert Lucas in the 1970s. It argues that traditional economic models, which rely on historical data to predict future outcomes, can be misleading. This is because these models often fail to account for changes in people's expectations and behaviors when policies change. According to the Lucas Critique, when policymakers implement new strategies, individuals adjust their actions based on anticipated outcomes. Therefore, to accurately assess the effects of policy changes, models must incorporate how expectations evolve, rather than solely relying on past data. This insight has significantly influenced modern macroeconomic analysis.