Changing minds: Political arguments and political persuasion

Theory: Just as persuasion is the crux of politics, so too is argument the key to political persuasion. Political arguments about policy have at least two dimensions, namely, whether the argument is for or against the policy and whether the argument is hard or easy to comprehend. Combining these two dimensions leads to four argument types: hard-pro, hard-con, easy-pro, and easy-con. Our purpose is to determine which of these four types more strongly influence citizens' policy judgments. Hypotheses: Con arguments will be more persuasive than pro arguments. The literature does not offer a clear prediction about the relative effectiveness of hard and easy arguments or the four argument types. Methods: We use a within and between experimental design, measuring subjects' opinions about NAFTA and health care at three points in time. Opinion change is analyzed by ANOVA. Results: Arguments against NAFTA and health care worked especially well. On NAFTA con arguments were most persuasive when they were also hard, on health care when they were also easy. Political awareness mediated the effectiveness of arguments across both issues, while the intensity of partisanship mediated only on health care. We attribute this latter difference to the partisan split in Congress on health care, a split that did not emerge on NAFTA.