Parsons was a nasty piece of work.
Kind of a one-subject Edison, who was no prince either.
Left his initials on the Jet Propulsion Laboratory, so they’re also left all over the surface of Mars, by the wheels of the Curiosity rover.
Robert Heinlein was part of his circle for a while. A Parsons-like character appears in several of Heinlein’s novels. Some think that Heinlein told the FBI about Parson’s antics, which is why they kept an eye on him. The government gave him (Parsons) a lot of money to develop rockets.
Supposedly, scientology grew out of a conversation involving Hubbard, Heinlein, and another SF writer I don't recall. Hubbard's thesis was that writing for a penny a word was no way to get rich; if you were serious about it, you'd start a religion. Which Hubbard proceeded to do ... and also write massive tomes, as though he was still getting paid a penny a word.