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In March 2004, the Republic of Ireland became the first country in the world to ban smoking in indoor public places, including bars and restaurants.
Every country that eventually followed suit wrestled with the same arguments. The bans were seen as a good idea for health reasons, but widely opposed as being against civil liberties, and potentially disastrous for the hospitality industry.
In 2005, only a third of British adults supported a full smoking ban in pubs, which was ultimately implemented in 2007. By 2014, 82% supported keeping it in place. No polling institute is even asking the question anymore.
One reason behind this huge change in opinion is that smoking itself is now much less common in most countries (partly a result of the bans themselves). But long-term trends cannot explain the fact that all over the world the popularity of smoking bans increases dramatically almost immediately after they are imposed.
Economics though, can help to explain this change of perception – and how humans are sometimes more accepting of change than we might think.
Game theory, the study of strategic choices, describes this kind of phenomenon as “multiple equilibria”. Simply put, it means that when our own choices depend on the choices of others, there is sometimes more than one possible outcome – and no reason to believe that one is more natural or stable than the other.
So with smoking, in one situation (or equilibrium), almost every pub used to allow smoking and that was generally considered normal and acceptable. Twenty years on, we have shifted to another equilibrium where a lack of cigarette smoke in pubs is the norm.
Once you get used to the idea, you can see the concept of multiple equilibria everywhere.
For instance, roads have two sides, and in some countries you drive on the left, in others you drive on the right. The two conventions are states of equilibrium. If everyone has agreed to drive on the left, you drive on the left too. It would be dangerous not to. But if everyone drives on the right, you do the same.
Urban planning is another example. When a city starts taking space away from cars, through pedestrianisation or adding bus lanes, it is always controversial. But after more space is given to public transport, research suggests that the quality of the service tends to improve, and attracts more customers.
These new customers stimulate demand, which means public transport becomes more regular, making it even more attractive.
And with fewer cars, walking and cycling become safer and more enjoyable too, so less space for cars does not lead to higher congestion. In Barcelona or Brussels for instance, car ownership decreased following large reductions in the space given to cars, and those who have a car simply use it less.
In this situation, there are again two equilibria: one where most people drive and more space is provided for cars, and another where few people drive, and a majority support wider pavements and bike lanes. A recent UK report found that more than twice as many residents of low-traffic neighbourhoods support their local scheme than oppose it.
Or consider how much time and attention we give to social media. There is evidence that many teenagers have a fear of missing out on these platforms, so spend time on Instagram or TikTok largely because they expect their friends to be on it. But there is an equally viable alternative: a parallel world where nobody joins social media and there is no interest in doing so.
Theory and reality
One problem with multiple equilibria is that they often remain theoretical. The only way to prove they exist is when someone has managed to coordinate a switch to a different one, like with the smoking bans.
A personal attempt to achieve this happened a few months ago, when a car nearly hit my daughter as I walked her to school along a pavement. The road in question is always busy with cars on the school run, with vehicles jostling for parking spaces on the kerb.
My interest in multiple equilibria led me to try and convince my local council to at least stop cars driving on the pavement while children were walking, cycling or scooting to school. I argued that it would make everyone safer and healthier. In fact, we know from a pilot project in Birmingham that banning cars altogether around some schools at drop off time does not increase congestion.
I didn’t succeed. And I can’t really blame my local council for claiming that taking away space from cars would just send more of them on to other roads nearby. I was canvassing for a different situation – an alternative equilibrium – which would require a big change, from the vested interest of a pedestrian parent.
And it’s also true that changing equilibrium can create winners and losers. Some bars had to close because of the smoking bans, and some smokers no doubt wish they could still light up in their favourite pub. Some young people are much happier socialising virtually than in person. And some parents really love their cars.
But 20 years ago, Ireland showed us that things that once looked inconceivable – like pubs that weren’t hazy with cigarette fumes – can very quickly become normal. It showed that there is not always just a single equilibrium, one way of doing things, which reflects most of our preferences. Jumping from one equilibrium to another is not easy – but as a society we can, and sometimes do, make significant changes to the way we live.
Renaud Foucart does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
