Persuasion: From Single to Multiple to Metacognitive Processes.

This article provides a brief overview of major developments in the history of contemporary persuasion theory. The first intuitive and empirical approaches to persuasion were guided by main-effect questions (e.g., are experts more persuasive than nonexperts?). Furthermore, researchers focused on only one process by which variables (e.g., emotion, source credibility) would have an impact (e.g., emotion affected attitudes by classical conditioning). As data began to accumulate, so many new theories and effects were uncovered that the discipline faced collapse from the numerous inconsistencies evident. In response to the reigning confusion of the previous era, contemporary multiprocess theories were proposed (e.g., the elaboration likelihood model). According to these more integrative approaches, any one variable could affect attitudes by different processes in different situations and thereby sometimes produce opposite effects. Finally, we describe the role of a recently discovered new contributor to persuasion: self-validation. Unlike previous mechanisms that focus on primary cognition, this new process emphasizes secondary or meta-cognition.