A man takes out a lavish, grossly excessive insurance policy on his wife. The next day she keels over dead. Which hypothesis should guide the detective assigned to the case? (A) Itâ€™s probably just a coincidence, no need to investigate. (B) Thereâ€™s a significant probability of foul play, so the husband should be considered a suspect, at least until a thorough investigation definitively clears him.
Intuitively, most of us k now that the correct answer is â€œB.â€ We donâ€™t need probability theory to tell us that, any more than we need Einstein to tell us that Jeffrey Epstein didnâ€™t kill himself.
But wait! Here comes a mathematically-inclined professional debunker, who explains: â€œActually, more than ten million life insurance policies are taken out every year, with the insured person averaging 19.2 years of life expectancy after the initial policy purchase, so 500,000 annually-insured people die each year which means more than 1300 annually-insured people die each day. The insured wife in your example could easily have been one of those 1300 people who just happened to die on that particular day, which just happened to be the day after the husband bought the policy. So it must have been a coincidence. No need to investigate.â€
Wikipedia, The New York Times, Snopes, DHSâ€™s Disinformation Governance Board, and assorted fact-checkers all agree. Social media labels people who suspect the husband of murder and insurance fraud â€œconspiracy theoristsâ€ and disables the accounts of those who voice their suspicions.