Exciting falsehoods tend to do well in the perpetual referenda, and become self-validating. A search for almost any “alternative” theory or belief seems to generate more links to true believers’ pages and sites than to legitimate or skeptical ones, and those tend to dominate the first few pages of results. For instance, beginning in the ’90s, conspiracists decided that contrails, the skinny clouds of water vapor that form around jet-engine exhaust, were composed of exotic chemicals, part of a secret government scheme to test weapons or poison citizens or mitigate climate change—and renamed them chemtrails. When I Googled chemtrails proof, the first seven results offered so-called evidence of the nonexistent conspiracy. When I searched for government extraterrestrial cover-up, only one result in the first three pages didn’t link to an article endorsing a conspiracy theory.