Empirical investigations of metaphor's persuasive effects have produced mixed results. In an effort to integrate the literature, we present a review and meta-analytic summary of existing studies. Six explanations for the potential suasory advantage of metaphor over literal language were reviewed: (a) pleasure or relief, (b) communicator credibility, (c) reduced counterarguments, (d) resource-matching, (e) stimulated elaboration, and (f) superior organization. Next, a meta-analysis was conducted and the impact of seven moderator variables was tested. The overall effect for the metaphor-literal comparison for attitude change was r = .07, which supported the claim that metaphors enhance persuasion. The effect rose to r = .42 under optimal conditions, when a single, nonextended metaphor was novel, had a familiar target, and was used early in a message. Metaphor appeared to exert a small effect on perceptions of source dynamism (r = .06), but showed no demonstrable impact on competence (r = -.01) or character (r = -.02). Of the six theories considered, the superior organization explanation of metaphor's persuasive impact was most supported by the results.
All Science Journal Classification (ASJC) codes
- Developmental and Educational Psychology
- Linguistics and Language