How to really change someone’s mind

I’ve been thinking recently about three debates. In the first, which took place in January 2016, two Harvard students, Fanele Mashwama and Bo Seo, proposed that “the world’s poor would be justified in pursuing complete Marxist revolution”. In the second, in October of the same year, Hillary Clinton and Donald Trump debated which of them should be the next president of the United States. In the third, author David McRaney discussed the shape of the planet on which we live with Mark Sargent, a man best known for his popular YouTube videos asserting that the Earth is flat.

I have my own views about all three topics, but what intrigues me here is form rather than content. What does it mean to have an argument with someone? What goals are served by different styles of debate? And, most importantly of all, if you hope to persuade someone else to change their mind, how should you do it?

Mashwama and Seo were debating in a formal contest, the world championship, no less. They won, but not because they convinced anyone that a Marxist revolution was justified. (I suspect they did not even convince themselves of that.) You win a debating contest in much the same way that you win a figure-skating competition: by convincing the judges that you have produced a superlative performance, judged against established standards and rules.

The Clinton-Trump debate also had rules, but not the same kind. Trump arguably broke those rules more than Clinton, but if moderators Anderson Cooper and Martha Raddatz had declared that Trump had been disqualified, and that Clinton was therefore president-elect, everyone would have concluded that Cooper and Raddatz had lost their minds. In politics, the rules of debate exist to be broken, and they often are broken deliberately for calculated effect.

McRaney’s discussion with flat-Earther Sargent was different again. McRaney did not offer evidence or argument that the Earth is near-spherical, neither did he mock Sargent in the hope of turning the audience against him. Instead, he largely gave the floor to Sargent, asking him to explain his reasons and gently inviting Sargent to reflect further on whether the evidence supported his ideas. It was a radically different view of what a disagreement might look like.

So what was McRaney trying to do? His new book, How Minds Change, explores why some world views seem so stubbornly immune to reason and why people will nevertheless change their minds in the right circumstances. McRaney suggests that most people believe what they believe based on social cues and that this is a reasonable way for social primates to conduct themselves.

One consequence of this tribalism is that we rarely examine in detail any of the reasons that we believe anything. In principle, that problem should be solved by the kind of logical, good-faith debate that Bo Seo advocates in his book Good Arguments (US) / The Art of Disagreeing Well (UK). In practice, most people do not react well to having their beliefs dismantled by a skilled debater. No matter how civilised, it feels like a frontal assault and the cognitive drawbridge is quickly raised.

Hence McRaney’s softly softly approach, inspired by conversational techniques such as “street epistemology” and “deep canvassing”, which sometimes trigger remarkable conversations.

McRaney describes a deep canvassing interview conducted in California before same-sex marriage was legal. It begins when a campaigner for equal marriage rights knocks on the door of a septuagenarian gentleman and begins a conversation. At first, the man is sceptical. The “gay community” make such a ruckus demanding more rights, he says, but the country has enough problems without all that.

But as they talk, the canvasser asks the man about his own marriage. Married for 43 years, says the man. His wife died 11 years ago. He’ll never get over it. The canvasser listens as the man talks about his wife, how much he misses her, and the way she died. They were so happy together. And then, unprompted, he says, “I would want these gay people to be happy too.”

During deep canvassing interviews, says McRaney, people “talked themselves into a new position so smoothly that they were unable to see that their opinions had flipped”.

Not always, of course. McRaney’s conversation with Sargent was friendly and thoughtful, but he had no more success in prompting Sargent to reject flat-Earthism than he would have had in prompting the Pope to renounce Catholicism. So did McRaney fail? Perhaps. But the conversation ended in a tone of mutual respect; the door was open for McRaney to try again. I have seen many disagreements go worse.

Debate feels like it should work the way Seo wants it to work. I share his love of the ideals of debate: logic, turn-taking, listening as well as talking, non-violence. I am not optimistic that it often works in practice. Perhaps the deep problem is that formal debate is a performance, like professional wrestling. Audiences pick a side and enjoy the show.

But people do not usually change their minds because they enjoy a show, nor even because of a dazzling display of logic. People change their minds because they persuade themselves. Rapport, listening and inviting people to elaborate can all open a space for that self-persuasion to happen. But a world champion debater cannot change your mind; only you can do that.

Written for and first published in the Financial Times on 8 July 2022.

The paperback of The Data Detective was published on 1 February in the US and Canada. Title elsewhere: How To Make The World Add Up.

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