How do you react when someone politely but firmly tells you that you’re talking nonsense about something that’s important to you? Do you gracefully and immediately give way to their greater expertise? Or do you double down? Most of us are in the latter camp. Voicing our beliefs tends to solidify them. We may like to think of ourselves as rational creatures, constantly assessing the world for new information that might change our minds, but this is not how our brains work. Explaining to someone that their belief is flat-out wrong is not a good way of getting them to drop it. And research shows that the process of “myth-busting” – setting out a common false statement, then explaining why it is wrong – backfires because it counterintuitively reinforces and helps spread the myths. This is why the premise of last week’s Question Time was so flawed. The presenter of the BBC programme, Fiona Bruce, announced in mid-January that the programme wanted to explore why some people had chosen not to be vaccinated against Covid and specifically invited them to apply to be an audience member on the programme. Understanding why some people have not yet been vaccinated despite the wealth of evidence that the vaccines are safe, effective and save lives is hugely important to improving take-up. But there are numerous research reports on this to which a current affairs programme such as Question Time has little to add. And if the objective was instead to increase understanding and build empathy among viewers, its tribal format, in which rhetorical flourish is deployed to score quick wins over opponents, could not be less well suited to the task. In response to widely aired concerns, the programme said it would vet potential audience members to allow ordinary unvaccinated members of the public through while filtering out the fanatics. This is to misunderstand that the expression of reasonable-sounding doubts can be a much more effective transmitter of misinformation than ranting and raving. And sure enough, the programme ended up falling into a number of disinformation traps. The audience member who challenged the panel on vaccine effectiveness was given a huge platform to make a number of false statements about Covid vaccines, including that they have “fairly horrific” side effects whose incidence we do not know. The highly respected immunologist on the panel, Robin Shattock, comprehensively debunked them, while also expressing respect for people who question the evidence. When the audience member challenged Shattock, saying he had looked at the data himself, citing a report to suggest there may be under-reporting, Bruce reminded him of the latter’s credentials. The clip of this exchange will have been viewed many more times than the programme itself: it has gone viral on social media and been widely reported in the press. The tone with which it has been shared has been overwhelmingly positive, with a dash of mocking – isn’t it great how well this misinformation has been demolished (and enjoy someone getting truly owned by a leading expert)? This is because that is exactly what people who have zero doubts about vaccines see: a clip that resoundingly debunks anti-vax myths. But research about how we react to misinformation suggests people with doubts about vaccines, who are less inclined to trust scientific authority, might have seen something different. Dangerous misinformation about vaccines was repeated, reinforcing things they have already heard. Someone who shares some of their doubts was talked down to on the basis of some credible-sounding questions about the legitimacy of data, which may have left them feeling just as confused. The sneery tone of the headlines and social media posts might have felt aimed at them too. This is no criticism of Shattock, who I think did the best job he could under the circumstances, but it is a prime example of a counter-productive piece of public health messaging. Overall, information around vaccines in the UK has been excellent, focusing on the positive story about why to get vaccinated, avoiding the repetition of misinformation by myth-busting and complex explanations that many people do not engage with. But this episode shows the extent to which it is harmful public health messaging that is more likely to go viral. Question Time also bought into another piece of conventional wisdom that disintegrates on close examination: the idea that on most issues people can be divided into tribes based on their fixed beliefs. The whole endeavour was based on the premise that “the unvaccinated” are a group of people who have been “unrepresented” on our national broadcaster, as if they share a coherent set of attitudes. But people have not yet been vaccinated for all sorts of reasons. Imagine thinking it useful to sort a Question Time audience on the basis of other unhealthy behaviour, such as smoking or excessive drinking. While conspiracy thinking can exert a strong pull, in-depth attitudinal research illustrates that people can hold conflicting beliefs at the same time and that they might appear to be in one “tribe” or another depending on how a conversation is framed. For example, a study that interviewed 60 people for two hours each on racism found many people simultaneously hold beliefs that are helpful and unhelpful for anti-racism campaigns. “The idea that there are fixed groups of people – pro-vaccine, anti-vaccine and a persuadable group in the middle – is a massive oversimplification that can become a self-fulfilling prophecy,” Nicky Hawkins, a communications expert who has researched vaccine messaging, tells me. Indeed, people are still coming forward to have their first vaccination, suggesting some are still changing their mind. Too many of us buy into the old, and slightly vain, liberal idea that good and rational speech will always win out over bad and logically incoherent speech. And that people who disagree with us are less complex and more stupid than we are. Freedom of expression is critical to democracy in its own right, but insights from cognitive psychology put paid to the idea that the truest idea will win out, particularly in a world where social media platforms make most profit out of the stuff that hardens our views by making us angry. Campaigners who want to change minds have to be much smarter than simply explaining what makes other people so wrong. Sonia Sodha is an Observer columnist