Mental Immunity

Why do so many implausible beliefs keep gaining ground? Covid denial clings on despite mountains of evidence, vaccine refusal puts communities at risk, and conspiracy thinking has fuelled violent mobs. Partisan hostility is tearing countries apart, climate denial has brought the planet to a dangerous tipping point, openly neo-Nazi groups march in public, and the claim that the Earth is flat has resurfaced. Andy Norman asks what is driving all of this and what can be done about it.

Norman argues that these troubling trends have a common source. A widespread belief that everyone's opinion deserves protection, whatever its merits, has weakened our ability to resist bad ideas. In his account, conspiracy theories, ideologies that ignore evidence, and everyday falsehoods are all forms of what he calls mind parasites, each using clever tactics to get past the defenses of the individual mind. Some of these parasites also undermine cultural defenses, the collective habits and institutions societies use to keep harmful ideas from taking hold. Norman contends that minds and cultures do have immune systems, that those systems can fail, and that they can be strengthened against ideological infection.

To make this case, Norman calls for a rigorous science of mental immune health, which he names cognitive immunology, and considers how such a field could transform the practice of critical thinking. The book works as a practical guide to recognizing and discarding bad ideas, while also making a broader appeal for people to set aside narrow tribal loyalties and think more clearly together.