Some people will believe anything, literally anything. People so stupid, it is amazing that they remember to breathe. Sadly, they do still seem to be able to pass the procreation practical exam.
Just in case you know just such a person who believes that the world is flat, or that man has not walked on the moon, here I offer you a conspiracy theory generator.
Obviously, it generates utter bollocks, but you could probably sell these to a newspaper or even hook in a flat earther long enough to delay them reproducing.
