Anti-vaxxers, conspiracy theorists, climate change deniers. The ranks of those who, for whatever reason, insist on labelling as "unreliable" certain positions that have been widely verified by the scientific community show no sign of shrinking, despite the numerous informational and educational initiatives dedicated to issues that have by now become genuine environmental, health or social emergencies.

The psychological roots of denialism

This attitude — that of climate change deniers, and science deniers in general — is rooted in complex reasons of social psychology, in the Western myth of self-determination (even in the face of theses verified by scientific method) and in the tendency to reinforce one's own convictions by surrounding oneself with friends, real and virtual, who share them. According to a recent study by the Universities of Berkeley, Rochester and California, for example, many individuals tend to base their beliefs on the social consensus these beliefs guarantee them within their own environment, rather than on scientific evidence and statistical data.

The so-called Dunning-Kruger effect also contributes to reinforcing the anti-scientific opinions of deniers: this is a psychological phenomenon whereby individuals with little expertise in a given field tend to overestimate their own competence. Because of this bias, scientific evidence ends up representing a kind of psychological threat and causes climate change deniers — and others — to "close up" even further, pushing away any possibility of reconsideration and paradoxically reinforcing anti-scientific prejudices.

How to talk to climate change deniers

Behind the most entrenched scientific denialism, then, lie motivations that are first and foremost psychological in nature, but the journalistic language used to communicate scientific emergencies also matters. In recent months, it is no coincidence that the Guardian announced it had updated its style guide for terms related to environmental reporting and, in particular, to climate emergencies. The publication, for example, chose to refer to climate change as "climate crisis", in order to give readers a greater and more immediate sense of the gravity of the situation. For the same reason, the term global warming was replaced by the more drastic global heating. "We want to make sure we are being scientifically precise, while also communicating clearly with our readers on this crucial issue," explained the Guardian's editor-in-chief, Katharine Viner.

Communication strategies against disinformation

Choosing the right words can, then, make a difference when talking to science deniers (and climate deniers in particular). According to Cornelia Betsch and Philipp Schmid, researchers at the University of Erfurt in Germany, beyond lexical solutions, the communication strategies adopted matter greatly. The two most effective for countering disinformation and anti-scientism are: the first, based on refuting the denialist thesis, involves countering disinformation with established facts, point by point, but its effectiveness can be undermined by the Dunning-Kruger effect and other psychological implications.

The second strategy, known as technical rebuttal, consists instead of exposing the methods used by science deniers to mislead their audience. In a study published in Nature Human Behaviour, the two researchers argue that technical rebuttals appear to be a particularly effective tool, given that the methods used by science deniers tend to be very similar.

These range from insisting on circulating isolated — and easily refutable — studies that support an unconventional point of view (for example: the correlation between vaccines and autism) to attempting to discredit entire fields of science on the basis of unrealistic and unreasonable expectations (for example: vaccines are not 100% free of side effects and therefore cannot be considered reliable). Understanding these techniques used to spread scepticism can be very useful for countering denialism. "If you learn this method once, you can use it with very different arguments," explains Betsch, "but you need to have a thorough knowledge of science, which requires continuous study."