Abstract

Scepticism is a disease in which healthy mental processes run pathologically unchecked. Our cognitive immunity system, designed to protect our conception of the world from harmful errors, turns destructively on that conception itself. Since we have false beliefs, we benefit from the ability to detect our mistakes; removing our errors tends to do us good. Our cognitive immunity system should be able to destroy bad old beliefs, not just prevent the influx of new ones. But that ability sometimes becomes indiscriminate, and destroys good beliefs too. That can happen in several ways. I start by considering two of them.