The Maths of Rightwing Populism: Easy Answers + Confidence = Reassuring Certainty

In psychology, this effect is known as confirmation bias. It is often interpreted as an irrational or illogical trait of our behavior, but we now understand the science behind it by borrowing concepts from communication theory. I call this a “tenacious Bayesian” behavior because it follows from the Bayes theorem of probability theory, which tells us how we should update our perspectives of the world as we digest noisy or uncertain information.

A corollary of this is that if someone has a strong belief in one scenario which happens to represent a false reality, then even if factual information is in circulation, it will take a long time for that person to change their belief. This is because a conversion from one certainty to another typically (but not always) requires a path that traverses uncertainties we instinctively try to avoid.

Polarized Society
When the tenacious Bayesian effect is combined with Wiener’s second law, we can understand how society becomes polarized. The second law says there will be a lot of diverging information and noise around us, creating confusion and uncertainty. We are drawn to information that offers greater certainty, even if it is flawed.

For a binary issue, the greatest uncertainty happens when the two alternatives seem equally likely – and are therefore difficult to choose between. But for an individual person who believes in one of the two alternatives, the path of least uncertainty is to hold steady on that belief. So in a world in which any information can easily be disseminated far and wide but in which people are also immovable, society can easily be polarized.

Where Are the Leftwing Populists?
If a society is maximally polarized, then we should find populists surging on both the left and right of the political spectrum. And yet that is not the case at the moment. The right is more dominant. The reason for this is, in part, that the left is not well-positioned to offer certainty. Why? Historically, socialism has rarely been implemented in running a country – not even the Soviet Union or China managed to implement it.

At least for now, the left (or centrists, for that matter) also seem a lot more cautious about knowingly offering unrealistic answers to complex problems. In contrast, the right offers (often false) certainty with confidence. It is not difficult to see that in a noisy environment, the loudest are heard the most.

Today’s politics plays out against a backdrop of uncertainties that include wars in Ukraine and Gaza with little prospect of exit strategies in sight; the continued cost of living crisis; energy, food and water insecurity; migration; and so on. Above all, the impact of the climate crisis.

The answer to this uncertainty, according to rightwing populists, is to blame everything on outsiders. Remove migrants and all problems will be solved – and all uncertainties eradicated. True or false, the message is simple and clear.

In conveying this message, it is important to instill in the public an exaggerated fear of the impact of migration, so their message will give people a false sense of certainty. What if there are no outsiders? Then create one. Use the culture war to label the “experts” (judges, scholars, etc.) as the enemy of the people.

For populists to thrive, society needs to be divided so that people can feel certain about where they belong – and so that those on the opposing side of the argument can be ignored.

The problem, of course, is that there are rarely simple solutions to complex issues. Indeed, a political party campaigning for a tough migration policy but weak climate measures is arguably enabling mass migration on a scale unseen in modern history, because climate change will make many parts of the world uninhabitable.

Wiener was already arguing in 1950 that we will pay the price for our actions at a time when it is most inconvenient to do so. Whatever needs to be done to solve complex societal issues, those who wish to implement what they believe are the right measures need to be aware that they have to win an election to do that – and that voters respond to simple and positive messages that will reduce the uncertainties hanging over their thoughts.

Dorje C. Brody is Professor of Mathematics, University of Surrey. This article is published courtesy of The Conversation.