Why are we asking this now?
Millions of people around the world, it is said, have this week watched a nine-minute video of the Hollywood actor Tom Cruise enthusing wildly about his faith in Scientology. Cruise and his co- believers keep lobbying internet bosses to remove it, but as fast as it goes down it is gleefully uploaded by one user after another. Cruise doesn't like it because it is a collection of incomprehensible snippets spliced together to make him and Scientology look wacky.
So what exactly is Scientology?
That's complicated. It starts out as a mental health/self- improvement technique. You begin with a "free stress test" on the high street, which diagnosed me as unstable, depressed, nervous, irresponsible, self-critical and withdrawn. If you take the bait, you are then offered a session of "auditing" in which a Scientology "E-meter" (which a US judged once described as "of no proven usefulness") reveals to your Scientology counsellor just how bad you are. A system of intensive, and expensive, counselling called Dianetics will then purge you of "engrams" - undesirable thought patterns resulting from misdeeds in past lives. The higher up the auditing levels you progress the closer you get to the state that the Supreme Being intended.
Does it work?
Lots of people think so. Various Hollywood celebrities have told interviewers how it gave them an important set of life skills or improved their marriage. On the other hand, those for whom it has gone terribly wrong have ended up in courts where judges have said of Scientology that it is "corrupt, sinister and dangerous" or that it is a "schizophrenic, bizarre, paranoid. . . organisation that harasses its enemies and abuses the trust of its members". Even so it claims to be the world's fastest growing religion.
How many people are Scientologists?
Like everything to do with Scientology that's controversial. Last year it claimed 3.5 million members in the United States alone but independent sociologists said the true number was more like 55,000 people. There may be 100,000 worldwide.
In what way is it a 'sci-fi religion'?
It was founded in the 1950s by a former science fiction writer, L Ron Hubbard. The belief was that human souls were the ghostly remnants of aliens known as Thetans who had been brought to the Earth millions of years ago by a cruel Galactic despot named Xenu and his evil minions (who lived on as Christian clergy and psychiatrists). Scientologists today claim this is a wilful misreading of a metaphorical understanding of the human soul as an immortal spiritual being (termed a Thetan) which has lived through many past lives and continues after death.
Auditing, Hubbard claims, can allow individuals to reach through to this pure state and become an "Operating Thetan" as native spiritual abilities are recovered. Scientology is in practice a jumble of hypnotic techniques, Freudian theories, Buddhist and Hindu concepts, Aleister Crowley-style occultism and Gnosticism.
Just who was L Ron Hubbard?
The erstwhile pulp science fiction writer Lafayette Ron Hubbard claimed to have been an acclaimed explorer, a nuclear physicist and a war hero. He was none of those according to Russell Miller, author of a biography called Bare Faced Messiah. He dropped out of college with failing grades, never saw combat and had two bigamous marriages. An American judge once said Scientology mirrored Hubbard's schizophrenic and paranoid personality. As a sci-fi writer he once said: "Writing for a penny a word is ridiculous. …