Astonishingly irrational ideas are spreading. Covid denial persists in the face of overwhelming evidence. Anti-vaxxers compromise public health. Conspiracy thinking hijacks minds and incites mob violence. Toxic partisanship is cleaving nations, and climate denial has pushed our planet to the brink. Meanwhile, American Nazis march openly in the streets, and Flat Earth theory is back.

In Mental Immunity, Andy Norman shows that these phenomena share a root cause. We live in a time when the so-called “right to your opinion” outweighs personal and cultural responsibilities, resulting in an ethos that compromises mental immune systems and allows “mind parasites” to overrun them. This is more than mere analogy: Norman demonstrates that minds and cultures do have immune systems that can break down. Fortunately, they can also be built up: strengthened against ideological corruption. Norman calls for a rigorous science of mental immune health – what he calls “cognitive immunology” – and explains how it could revolutionize our capacity for critical thinking.

Hailed as “a feast for thought,” Mental Immunity melds cutting-edge work in science and philosophy into an “astonishingly enlightening and productive” solution to the signature problem of our age.