These theories included allegations that climate change is a hoax perpetrated by the Chinese, that Barack Obama was not born in the US, and that vaccines cause autism. The potential impact and breadth of conspiracy theories was underscored in 2016, when Donald Trump was elected US President despite propagating a range of highly implausible conspiracy theories throughout his campaign. What drives belief in such conspiracy theories? While in earlier decades belief in conspiracy theories often was dismissed as pathological (Hofstadter, 1966), accumulating evidence reveals that conspiracy theories are common among surprisingly large numbers of citizens (Oliver & Wood, 2014 Sunstein & Vermeule, 2009). Conspiracy theories are commonly defined as explanatory beliefs about a group of actors that collude in secret to reach malevolent goals (Bale, 2007). In fact, conspiracy theories sometimes turn out to be true (e.g., Watergate incidents of corporate corruption), although the vast majority of conspiracy theories that citizens have believed throughout history have been false (Pipes, 1997). These theories range from highly implausible in light of logic or scientific knowledge (e.g., chemtrail conspiracy theories flat‐earth conspiracy theories) to theoretically possible or even plausible (e.g., allegations that secret service agencies routinely violate privacy laws).

Social media and the Internet are filled with conspiracy theories.

Conspiracy theories about flat earth