It’s hard to change people’s minds, especially when the issue feels like a moral one. Studies have shown that the more that people have moral reasons for an opinion, the less likely they are to change that opinion even after seeing compelling arguments that they’re wrong. But are moral opinions always this stubborn, or is there a way to get through to them? In a new set of studies, my colleagues and I wanted to see whether the durability of moral opinions might depend on how they’re attacked.

A person could try to persuade you in many ways, and one of these is to highlight the morality of his or her position. There’s no shortage of these moral arguments in the world, with people making a moral case for everything from prison reform to repealing soda taxes to self-driving cars. But do these tactics work? Are they enough to change people’s minds?

We thought that moral appeals might be just the thing to get through to people who hold an opinion for moral reasons. Having moral reasons for an opinion doesn’t necessarily mean that you’re intent on holding that same opinion forever—it just means you care about basing your  opinion on what’s morally right. So if a person ignores morality when trying to convince you to change your mind, you won’t be persuaded because that person didn’t challenge the reason you hold your opinion in the first place.

To see if this is the case, we tested how much people changed their opinion on an issue after seeing either a set of moral or non-moral arguments that challenged their initial view.

In one of these studies, we tested hundreds of people who said they were in favor of legalizing marijuana in the United States. Some of these people said that they supported legalization for moral reasons, and others said morality wasn’t a factor in their position. We asked all of these participants to read a short essay that argued against marijuana legalization, but we had created two different versions of this essay.

We had a random half of the participants read the “moral” version of the essay, which was titled “Legalizing Marijuana: Harmful and Immoral” and argued that legalization would unfairly harm marginalized groups and lead to the development of exploitative industries. We had the other half of participants read the “non-moral” version, which was titled “Legalizing Marijuana: Unwise and Impractical” and argued that legalization would be costly and difficult to regulate effectively. On average, the two sets of arguments were equally compelling, but they appealed to either moral or practical concerns. After reading the essay, the participants indicated their opinions on legalizing marijuana once more.

For people who read the message focused on economic and pragmatic (non-moral) concerns, our results looked like what prior studies showed: the more people thought marijuana legalization was a moral issue, the less persuaded they were by the essay. But this wasn’t the case for people who read the message that focused on moral concerns. Instead, for people who had moral reasons for their initial opinion, the moral arguments were more persuasive than the pragmatic arguments.

This finding shows that people can be open to new perspectives on moral issues as long morality isn’t ignored. But this also means that, for people who didn’t base their original opinion about legalization on morality, the moral arguments were no better than, and sometimes less persuasive than, the pragmatic arguments.

We found the same pattern of results when the topic of persuasion was recycling, and presumably the same patterns would emerge for other opinions as well.

As we inch closer to yet another presidential election in the United States, we’ll be seeing plenty of attempts at persuasion by hopeful candidates and plenty of talk about what’s morally right and wrong. Already, many of these candidates have framed key issues as moral issues in their attempts to win over voters, but our research suggests that their morality-based arguments might be more convincing for some voters than for others.

For Further Reading:

Luttrell, A., Phillip-Muller, A., & Petty, R. E. (2019). Challenging moral attitudes with moral messages. Psychological Science, 30(8) 1136-1150.


Andrew Luttrell is Assistant Professor of Psychological Science at Ball State University.