Abstract
Metaphor is ubiquitous in persuasive messages although the process by which its effects are achieved is still not fully understood. This study proposes that the emergent structural match between linguistic metaphor and long-term knowledge in the form of conceptual metaphor leads to the persuasive outcomes. To test this assumption, six predictions related to metaphor's effect on attitude judgment and speed of attitude judgment were tested. Three types of messages that contained a novel metaphor and additional message content in the form of conventional metaphors were compared: messages using the same conceptual metaphor to understand both the novel metaphor and rest of the message content (metaphor-fit condition), messages using different conceptual metaphors to understand the novel metaphor and rest of the message content (metaphor-nonfit condition), and literal equivalent of metaphorical messages (literal condition). Amount of prior familiarity of metaphor target as a condition for greater effectiveness of metaphor-using messages was also investigated. The hypotheses that metaphor-fit messages would have a stronger impact on attitude judgment and would exhibit faster attitude judgment response time than metaphor-nonfit and literal messages were partly borne out.