It took but a quick click, but even as I joined the collective expression of disgust on social media at last week’s Daily Mail “Legs-it” front page I felt a bit sheepish. Not because juxtaposing a headline that posed the question of who had better legs next to a photo of Theresa May and Nicola Sturgeon wasn’t deeply sexist, but because it was a futile gesture, and I knew it.

We lefties have impeccable pedigree when it comes to righteous outrage. It has a time and a place: there’s something life-affirming and motivating about asserting your membership of a tribe with common values. But it also carries something of the guilty pleasure: the smug satisfaction of earning your virtue-signalling stripes in our social media age.

Righteous outrage, far from winning people over, merely entrenches the ways of thinking we find anathema

This particular guilty pleasure brings risks. It can start to feel like a meaningful action rather than preaching to the converted – tweet sent, job done, don the feminist T-shirt. Once it spills over from the social media bubble into radio phone-ins and breakfast TV, there is a danger that righteous outrage, far from winning people over to our world view, merely entrenches the ways of thinking that leftists find anathema.

Changing people’s minds is a non-negotiable part of achieving social change. There is a longstanding body of psychological evidence that shows that lecturing people that they are wrong, listing a bunch of facts that conclusively demonstrate that, and busting the myths spread by irresponsible political opponents not only fails to change minds, it makes people more fixed in their views.

That’s the bad news for campaigners on the left, who tend to be some of the most enthusiastic adopters of such approaches.

The good news is that there’s usually a sizeable group of people who are persuadable, at least to some degree, on a particular issue. The way to do it, though, is to find ways of articulating the case for change that appeal to the values that are important to them and their own ways of thinking about the world, rather than trying to change their world view altogether.

These insights aren’t new. But the left has not, on the whole, been very good at taking them on board. As someone who’s worked in and around the charity sector for a number of years, I’ve seen countless campaigns based on facts and myth-busting, built on worthy explanations setting out why people’s world views are wrong.

Anti-poverty campaigns are a good example: well-meaning strategies often embrace the approach of using statistics and stories to challenge the idea benefits claimants are scroungers. But research undertaken by the FrameWorks Institute for the Joseph Rowntree Foundation shows that trying to unpick the sort of thinking that leads people to see claimants as benefits scroungers is entirely counter-productive, entrenching these views rather than shifting them. It suggests that campaigners would instead be better off ignoring the scrounger narrative altogether and leading with a different sort of frame: the impact that poverty has on people’s freedom to live their lives.

Why have things been slow to change? Liberals love to think of themselves as rational, open-minded and enlightened; some might say of a superior ilk to everyone else. The great irony is that the wealth of evidence that classic liberal campaigning strategies are completely ineffective has failed to change liberal behaviour. That’s because liberals are subject to all the same cognitive biases as everyone else. I know I am: I respond differently before I’ve set out my views publicly in a column to afterwards. Not wanting to be shown up as wrong is a basic instinct you have to work incredibly hard to try to switch off.

Furthermore, the implicit moral superiority that’s often part and parcel of being on the left can get in the way of engaging with people whose views we find uncomfortable. We put arguments that address what we find morally objectionable or outrageous about their view front and centre, rather than the pragmatic arguments that might be most likely to win hearts and minds.

Take public attitudes to rape, for example. Research by Equally Ours, a campaign set up by charities to help campaigners rethink the way they make the case for human rights, finds that around half the population have unambiguous views, either believing women are never to blame for rape, or that they are often to blame. But around half of us share some aspects of both these world views: these are people probably persuadable in either direction.

Facebook Twitter Pinterest Michelle Obama’s reaction to Donald Trump’s misogny was effective because she reacted as a human being. Photograph: The Washington Post/Getty Images

Nicky Hawkins, who runs Equally Ours, sees an important distinction in the way Hillary Clinton and Michelle Obama reacted to the misogyny of Donald Trump. “Clinton reacted as a feminist, saying women have the power to stop him,” she says. “Obama reacted first and foremost as a human being, talking about how it made her feel as a woman and a mother, and how these behaviours impact on women’s everyday lives.”

As uncomfortable and counter-intuitive as it might be, taking the time to understand where other people are coming from can pay rich dividends. Support for gay marriage in the US has increased by a remarkable 20 percentage points in the past decade. This marked shift in social attitudes came about as a result of a campaign articulated not primarily in the language of rights but in the conservative values of love, commitment and family, which deployed the right champions – including heterosexual people – to spread the message.

It’s human to want to win people round to your own personal world view through forceful argument. But ignoring the irrefutable futility of this approach borders on self-indulgence. I, for one, am going to endeavour to think before I click in future.

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