In the early 1960s, William McGuire discovered that minds behave as if they have immune systems: expose a mind to a weakened form of an argument, and the mind will become resistant to full-strength versions of the same argument. This finding illuminates how propagandists, demagogues, and purveyors of orthodoxies close minds to new evidence. Hundreds of studies now speak to the existence of mental immune systems.
Learn more about Inoculation Theory
In recent years, experimentalists like Sander Van der Linden, John Cook, and Stephan Lewandowsky have shown that it's possible to inoculate minds against misinformation, climate denial, and conspiracy theories. In effect, they've shown that, with the right approach, it is possible to strengthen the mind's immune system.
Yale psychologist Dan Kahan has shown that people are highly resistant to information that threatens their identity. He calls the phenomenon "identity protective cognition," and it appears to correlate with some deep mental immune disorders. Along similar lines, Philip Tetlock has shown that the embrace of "sacred values" can make thinking certain thoughts taboo—in effect increasing our resistance, or immunity, to information that might destabilize conviction.
Social and cognitive psychologists have been studying susceptibility to mistaken views for decades. The research has revealed dozens of cognitive biases. Because mental susceptibility and mental immunity are two sides of the same coin, findings on susceptibility are also findings related to underdeveloped or compromised immunity. Gordon Pennycook and his team have found that, if you lose the "metabelief" that beliefs should change in response to evidence, you become more susceptible to disinformation, conspiracy thinking, and delusion. This implies that this essential metabelief confers mental immunity. Andy Norman (CIRCE's founder) argues that this metabelief is the linchpin of the mind's immune system.
Scientists now speak openly of "infodemics," acknowledging that bad information can spread like a virus through social networks, compromising the health and wellbeing of its human hosts. It's high time we came to terms with the obvious: