Why are conspiracy theories so popular? We may not always believe what we're told, but we still can't resist listening to them. Guy Smith, producer of 9/11: The Conspiracy Files, suggests the answer may lie deep within us all.
I admit it. If I'm being really honest, I can't deny that I'm a bit of a conspiracy theorist. Perhaps we all are.
It's easy to dismiss all conspiracy theories as "bunkum", but remember just occasionally they do turn out to be true. Remember Watergate? Iran-contra? Special Branch collusion with loyalist terrorists in Northern Ireland?
As Jim Fetzer, one of the leading 9/11 conspiracy theorists, says: "Just because you're paranoid, doesn't mean they aren't out to get you."
I've just spent the best part of nine months investigating the numerous conspiracy theories surrounding the al-Qaeda attacks on 11 September, 2001. They range from the plausible - that intelligence agencies in the Middle East may have had some inside knowledge about what was planned - to the totally wacky - that United 93's passengers were abducted by government agents.
But the deeper you dig in the dark world of conspiracies, the more you realise that different theories share much in common. The conspiracy theorist seizes on any apparent inconsistency and from that germ of truth the story is built up.
What happened to the white car apparently involved in Diana's accident? Was there a second gunman on the Grassy Knoll? And why did it take so long to scramble US fighters on 9/11?
And we can't help but be fascinated by them.
Perhaps it's because deep down, we're all story tellers. It's one of the things that makes us who we are. Since the dawn of time, we've been creating heroes and monsters as a way of trying to make sense of the world. In the beginning, we told those tales round camp fires. Now, it's through internet chat rooms or on mobile phones. But it's still basically the same process - weaving stories out of real life.
Tablets of clay
Nearly five thousand years ago, the legend of Gilgamesh was scratched on to clay tablets by scribes in ancient Mesopotamia, now Iraq. It's an epic tale of good guys and demons fighting it out in an uncertain world where those we love can be snatched from us at the whim of the gods.
Archaeologists believe it was the first story ever to be written down and as I researched the 9/11 conspiracy theories, I was struck how The Epic of Gilgamesh has many parallels with modern conspiracy theories.
One of the original conspiracies: the Epic of Gilgamesh
When something awful, inexplicable or just plain evil rocks our world, we have an instinctive need to construct elaborate explanations to try and make sense of our anxiety and fear.
Many eye-witnesses to 9/11 thought, "This terrible event can't just be something as simple as 19 young hijackers armed with pocket knives. There must be more too it than that - because the alternative is just too horrific to contemplate."
That alternative is a realisation we are all vulnerable to forces beyond our control; even princesses and presidents aren't immune to "everyday" tragedies like road accidents or random acts of violence.
"I believe the idea that conspiracy theorists are looking for a bigger reason is absolutely right," says Frank Spotnitz, writer of The X Files.
"I think the most potent targets for conspiracy theories are events of disproportionate tragedy. For example, the president of the United States is assassinated by a lone gunman. It doesn't seem fair, it doesn't seem right, it can't be. This one guy couldn't have done it - there must be larger forces at work."
And so we take comfort in complicated stories about wider conspiracies, usually involving remote, distant figures.
In the past it was mythical gods and monsters. In the more secular modern world, ancient superstitions have been discarded - now it's out-of-touch leaders and unseen government agencies who fill the role of the bogeymen.
We find it reassuring to create an explanation that vindicates our world view. It reinforces our beliefs, suspicions and, yes, even our prejudices.
And from Homer to Harry Potter, the stories we weave always have a hero who is trying to seek out "the truth". Their mission is to go where mere mortals fear to tread - whether it be the Minotaur's labyrinth or the labyrinthine recesses of the secret state - and bring back knowledge to share with the rest of us.
In the age of the internet, those fearless warriors are the self-styled conspiracy theorists whose hunting grounds are the furthest strands of the web. There one can find any number of rumours, stories or scenarios which can be strung together to create the perfect explanation for just about anything that goes wrong in the world.
Your rational half knows these theories probably aren't true, but our instinctive side thinks, well just maybe there's something in it.
In 5,000 years, we haven't changed at all. And maybe that's a very reassuring thing to know.
9/11: The Conspiracy Files was broadcast on Sunday, 18 February 2007 at 2100 GMT on BBC Two.
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I totally disagree with the author of this piece. Obviously he must work for an undercover government department and is trying to poo poo conspiracy theories. The reason I believe some CT's is not due to some romantic storytelling desire. It is because sometimes there are so many inconsistencies in the official versions of events. Also sometimes there is proof and evidence that something different happened to what the authorities (who may have their own reasons for you to believe differently) are telling you.
Steve Wilson, Weymouth, Dorset
I believe that every human being enjoys analysing different conspiracy theories, wouldn't life be dull without someone else's views? The fact is, we can't settle on a particular answer without totally checking every possible theory, whether it's a huge disaster such as 9/11 or who took the last of the lemonade.
It's human nature to question, that hasn't changed in 5,000 years, so therefore won't ever change. It's a way of life.
I think it's the factual discrepancies of 9/11, such as steel allegedly melting at an unnaturally low temperature, and the numerous anomalies around the Pentagon impact, that has given rise to doubts rather than any inability to deal with reality. If reality is causing a problem to anyone with that event, it will be the people who claim that the laws of physics changed beyond all recognition that day.
Sorry Chandra no conspiracy there, as a metallurgist I can tell you that the current evidence is not for any melting of steel in the WTC, rather a softening, as starts to occur at 425C. A quite normal event in any large fire.
The problem I have with many conspiracy theories is that they often rely on the fallacy that because of the perceived lack of evidence to support version A of why something happened, version B MUST be the right one. Imagine you are arrested for the murder of someone you have never met. You might not be able to produce any evidence that you weren't responsible, but that does not, on its own, mean that you MUST therefore be guilty. The police would need evidence that you were responsible at least on the face of it in order to charge you. The journalists involved in breaking the Watergate story revealed the "alternative" truth about the burglary, supported by evidence. Why don't we demand the same standards today?
Pie in the sky
There have been conspiracies in the past, so you can't dismiss a conspiracy theory on the grounds that conspiracies never exist. Second, the reason humans have a deep-seated weakness for these theories is that we are programmed to try to find patterns in order to explain the world. Sometimes the patterns are random and we impose a false order on the information, but it is wrong to say that this desire is anything to do with storytelling.
Grant , London UK
I have worked on a TV show called the Conspiracy Zone which aired on the now defunct TNN network. Conspiracy theories are like good gossip, everybody wants to hear - truth or not.
Iman Morales, New York City
I do not in principle disagree that conspiracy theories cannot always be attributed to such events as pointed out in your article. I also understand that in the cases of Diana and JFK we do tend to want to find the bogeyman lurking in the background. I am led to believe that the US government of 1941 knew about the Japanese coming to bomb Perl Harbour and allowed it to happen in order to overcome political opposition to joining WWII. It is a logical political thing to happen, however distasteful it may seem. By the same token I must ask myself if I could have sat quietly listening to a secret service agent telling me that an aircraft had been flown into the World Trade Centre and calmly continue reading to a group of school children? Either Bush is dumber than we all think or he was counting the aircraft, allowing it all to happen before reacting. The reaction being to commence the war on terror.
Tim Crilly, Hahnheim, Germany
Come now. Could it not be shock that something so audacious and devastating had been carried out? I remember that day, the entire office gathered in stunted silence around the TV. Natural reaction.
Bush's reaction was exactly the same as mine and everyone else I know: stunned silence. That probably makes him a rotten president - it doesn't make him a conspirator.
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