We are being swamped with dangerous nonsense. From 9/11 conspiracy theories to Holocaust denial to alternative medicine, we are all experiencing an epidemic of demonstrably untrue descriptions of the world. For Damian Thompson, the misinformation industry is wreaking havoc on the once-lauded virtues of science and reason. Unproven theories and spurious claims are forms of counterknowledge, and, helped by the Internet, they are creating a global generation...