By Melissa A. Wheeler

How do people construct arguments when they are attempting to persuade others to adopt their moral beliefs? Moral beliefs are often subjective and sometimes divisive. When we need to persuade others to join our side in a moral debate, we may frame our argument to contain appeals that we think will bolster our argument to make both the argument and ourselves seem more convincing to others. Effective persuasive communication may require the use of appeals that are grounded in the normative ethics of deontology (principle-based appeals), consequentialism (outcome-based appeals), or emotivism (appeals to emotions) to boost credibility and engagement from your listener.

Social psychologist Dr Simon Laham and I set out to explore the use of different kinds of appeals in moral persuasion and whether this is influenced by the nature of the subject under discussion.

Appeals used in justification across the moral domain

In a set of studies, we asked participants to read a series of moral violations representing each of Haidt and Joseph’s (2004) five moral foundations: Care, Fairness, Loyalty, Authority, and Sanctity. For each violation they were asked to select (Study 1) or construct (Study 2) a justification that would persuade someone else to agree with their moral judgment. After performing a linguistic content analysis of the responses, we discovered that people used different kinds of moral appeals in their justifications depending on what they were asked to talk about (i.e., the moral content of the violation they were responding to).

Certain appeals are more desirable in different moral contexts

Our results from two studies indicate a preference for consequentialist appeals when justifying violations of Care and Fairness (also known as the Individualizing foundations). For example, when talking about a moral transgression in which someone was bullied, participants tended to argue for their position by referring to the outcomes or repercussions of the perpetrator’s action—someone may have been affected or hurt—as opposed to abstract principles or emotions.

This may be unsurprising due to the fact that both the Individualizing foundations and the ethics of consequentialism focus on maximizing welfare, minimizing harm, and on social justice concerns.

Emotive appeals were more often selected and employed in justifications for the Binding foundations of Loyalty, Authority, and Sanctity. For example, when talking about a violation where someone was disrespectful to an employer, participants tended to argue for a particular position by discussing an emotional response—it makes people angry and upset—as opposed to consequences or moral codes.

It is notable that while all the moral foundations have been theoretically linked to emotional reactions and emotional content, our results indicate that emotions used as justifications are more prevalent for these three foundations.

We also captured an interesting preference for deontological appeals when justifying Sanctity (but also Care) transgressions, indicating that these foundations are more readily discussed in terms of violations of principles and are perhaps more strongly linked to clear rules and moral codes. For example, when talking about unconventional sexual practices, participants tended to argue by invoking a moral rule or code of conduct.

Implications for our daily lives

Much of our everyday moral decision-making occurs in social interactions and through communication. Therefore, it is vital that we increase our understanding of how people talk about morality – how we shape and transform our own and others’ attitudes toward moral issues.  

Our research going further will now focus on the effects of moral appeals across a range of moral content to explore if the kinds of appeals that people spontaneously generate are the same kinds of appeals that are actually effective in persuading listeners to shift their attitudes or preferences. Politicians and organizations alike would certainly benefit from knowing how to tailor their moral language use to suit the specific moral issue they are promoting, (or perhaps even a transgression they are justifying). Additionally, knowing how people tend to talk about morality might create more opportunities for successful dialogue between oppositional individuals or groups.

Melissa is a Postdoctoral Research Fellow at the Centre for Ethical Leadership and the Melbourne Poche Centre for Indigenous Health. She has a PhD in moral and social psychology from the University of Melbourne and currently focusses on the composition and persuasiveness of moral communication and in the area of applied ethics.