Evaluating classic and contemporary ideas about persuasion resistance in inoculation theory: argument strength, refutation strength, and forewarning

Despite more than six decades of research, foundational arguments about mechanisms proposed in inoculation theory to bring about persuasion resistance have gone untested. We conducted an experiment to examine a classic idea about the optimal strength of counterarguments and refutations in inoculation messages as well as a contemporary notion regarding forewarning. The results were inconsistent with the idea that weak counterarguments and strong refutations are optimal for fostering resistance. The contrast models examining the interaction between counterargument and refutation strength were not consistent with the expected patterns for traditional threat, motivational threat, counterarguing, or attitudinal resistance. The results did, however, offer some evidence for the importance of forewarning in inoculation messages. Including forewarning with a refutational preemption led to greater motivational threat relative to a refutational preemption without forewarning or a control message.