The Concept of Argument Quality in the Elaboration Likelihood Model

Abstract

Petty and Cacioppo's Elaboration Likelihood Model (ELM: see, e.g., Petty & Cacioppo, 1986) has been the most influential model of the persuasion process for almost two decades. Its basic postulate is that when people are confronted with a persuasive message, they want to assess the validity of the message's claim. To do so, people may systematically and critically evaluate the arguments supporting this claim. Although this systematic evaluation is the safest way to assess a claim's validity, people are not always motivated and/or able to do so. In that case, they can use rules of thumb to assess the validity of the message's claim. They may reason, for instance, ``Experts are usually right, and this claim is put forward by an expert, therefore this claim is correct.'' Other factors that can influence their assessment under those conditions are the number of arguments (instead of the content of these arguments), or even more superficial message characteristics such as the layout or the use of attractive colors. Depending on the way in which people process the message, arguments will or will not determine the outcome of the persuasion process. Only when people are motivated and able to systematically evaluate the arguments does the quality of these arguments influence their assessment of the claim's validity.