WE’VE a Scotsman to thank for the modern conspiracy theory. In 1797, John Robison, Edinburgh University’s highly-respected professor of natural philosophy, wrote a startling book called "Proofs of a Conspiracy against all the religions and governments of Europe, carried on in the secret meetings of Freemasons, Illuminati and Reading Societies etc, collected from good authorities".

It’s a long-winded title, but to summarise Robison, the Illuminati – a shadowy group of men intent on controlling the world – started the French Revolution to further their plan for global domination.

Like all good conspiracy theories, Robison’s contained a grain of truth. There was indeed a secret society called the Illuminati in the 1700s – but it was no more than a mystical masonic lodge, a talking shop for Enlightenment cranks. After the Bavarian government banned the Illuminati it took on a dark glamour and increasingly outlandish claims were made about it by hack writers of the day.

When the French Revolution shook Europe to its core, leaving people bewildered and asking how such a cataclysmic event could have happened, it became common to scapegoat the Illuminati – even though the group was all but defunct. Think of the Illumanati scare as a fore-runner of the "reds under the bed" conspiracy theory panic in 1950s McCarthyite America, Area 51, the millennium bug, MI6 murdering Princess Diana, faked moon landings, or Elvis alive and well out there somewhere. It makes a great story – but it just isn’t true.

Significantly, the Illuminati lives on today in the minds of many conspiracy theorists, like David Icke, as the dark hand behind the world’s woes.

On Tuesday, the United Nations observes Darwin Day to celebrate science and reason. Richard Dawkins will give the annual Darwin Day lecture. So, what better time to investigate the quintessential symptom of modern unreason – the conspiracy theory?

When it comes to conspiracy theories, there’s only one man to turn to – the world’s expert on the phenomenon, the psychologist Professor Rob Brotherton. He’s made an exhaustive study of psychological experiments which, when you put the results together, explain why humans seem hard-wired to believe in conspiracy theories.

"Conspiracy theories," he says, "resonate with some of our brain’s built-in biases and shortcuts, and tap into some of our deepest desires, fears and assumptions about the world and the people in it. We are all natural-born conspiracy theorists."

In his book Suspicious Minds: Why we believe in conspiracy theories, Brotherton explains that the fundamental feature of a conspiracy theory is "the ability to weave seemingly unrelated and inexplicable anomalies into a coherent story about sinister conspirators and their hidden agenda. Conspiracy theories are an exercise in connecting the dots".

Take one of the most dangerous conspiracy theories around at the moment – that vaccines cause autism. Some parents – after reading discredited medical claims – believe their children developed disorders after vaccination.

As Brotherton explains: "It is true that symptoms of developmental disorders like autism often become apparent between one and two years of age. It is also true that if parents follow the recommended vaccine schedule, their children receive a large number of vaccines at the same time.

"The overwhelming weight of scientific evidence, however, shows that the two are unrelated. The connection is nothing more than a coincidence of timing. But our intuition is rarely impressed by statistics. Our intuition wants the dots to be connected.’

In America, one-fifth of all adults believe doctors and the government "conspire to vaccinate children even though they know vaccines cause autism". You might think that sounds crazy – that it could only happen in America – but here in Britain, some 60% of us believe in at least one conspiracy theory.

When the Viking 1 probe photographed the surface of Mars, it sent back an image which looked like a giant face on the planet. It was actually a mountain – but that didn’t stop conspiracy theorists seeing proof of aliens. Watching planes fly into the Twin Towers, hasn’t stopped "9-11 Truthers" believing the US government blew them up.

The trait of seeing things that aren’t there is deep in our DNA. Brotherton suggests that among our ancient ancestors, those who mistook a log in a river for a crocodile and studiously avoided it were more likely to survive and pass down their genes despite having misinterpreted what they saw. The hominid who just wandered into rivers, thinking every thing they saw was a harmless log, was going to be eaten by a croc one day and vanish from the gene pool.

"A brain biased towards seeing meaning rather than randomness is one our great assets," says Brotherton. "The price we pay is occasionally connecting dots that don’t really belong together."

The human mind also has an "intention detector". We’re designed to assume things happen because someone intended it to happen. Randomness is not liked by humans. It’s easier to believe the Illuminati were behind the French Revolution, than a complex but random chain of historical events.

There’s a famous experiment from 1943 by Fritz Heider and Marianne Simmel in which they designed a short animation which shows a large triangle, a small triangle and a small dot moving around on screen. When the animation was shown to test subjects nearly all imposed a storyline on what they saw – some saw a fight, some domestic abuse. Our minds refuse to see what is really there: just a group of shapes moving meaninglessly.

Like the Kennedy conspiracy, there are enough unconnected pieces of information in the animation to make our inherently story-centred minds build a false narrative. So a narrative in which there’s a grand conspiracy by the CIA to murder the president, seems to make better sense than a much more random series of events where a mentally ill lone gunman kills JFK.

To the story-centred mind, it’s much more satisfying if the royal family killed Diana, than the random haphazard truth – that she died in a meaningless car accident.

However, although all humans have a story-centred mind, self-evidently we don’t all buy into conspiracy theories. You have to be "conspiracy-minded" as well. Brotherton says "people who believe conspiracy theories strongly tend to be a little more hostile, cynical, defiant of authority, anxious and disagreeable than people who dismiss conspiracy theories".

One study found that people who strongly agreed with claims like "most public officials aren’t interested in the average man" or "it is hardly fair to bring a child into today’s world" are more likely to believe in conspiracy theories. "The less satisfied with life people are in general, and the less control over their own circumstances they feel they have, the more likely they are to accept conspiracy theories," Brotherton says.

Another study found that more than three-quarters of people had paranoid thoughts at least weekly – with a third more frequently. "When you suspect people, especially authorities, of being untrustworthy," says Brotherton, "you’re probably going to take ‘official’ explanations with a grain of salt. If you think most people have sinister motives then conspiracy theories can make perfect sense. Paranoia goes hand in hand with conspiracy theories."

Think back to our ancient ancestors again. Early man and woman are sitting by their cave and over the hill comes another group of Cro-magnons. Who might be more likely to survive to pass on their genes – the couple who welcomed the unknown visitors with open arms, or the couple who picked up a spear and asked what the visitors’ intentions were – again, conspiracy lurks deep in our DNA.

Once you buy into one conspiracy theory – say JFK was killed by the CIA – then it’s easy to buy into more.

In one Austrian study, researchers invented a conspiracy theory – that the drink Red Bull contained an illegal chemical called "testiculus taurus" that makes people want more of the energy drink, and even makes lab rats grow wings. It sounds ludicrous, but the test subjects who accepted these claims also believed that 9-11 was carried out by the US government and that a New World Order is trying to take over the planet.

People who thought the Red Bull story was nonsense thought other conspiracy theories were nonsense.

The other problem with humans is that we think we know more than we do. We think we understand vaccines or bullet trajectories because we’ve read a few articles or watched a few films. But really, most people have little more than surface understanding.

One study gave participants a two-sentence description of nanotechnology – in effect, no information at all – yet nine out of 10 people felt they had enough detail to give an opinion on whether the science was good or bad. It proves the old adage "a little learning can be a dangerous thing".

Conspiracy theories also offer easy-to-digest, black-and-white solutions. Humans like simple choices. In 2011, psychologists surveyed 1000 people asking if politics was a struggle between good and evil. More than a third agreed – and the more people agreed with the statement the more likely they were to believe conspiracy theories.

The more someone tries to prove to a conspiracy theorist that their beliefs are wrong – that vaccines don’t cause autism, that 9-11 was carried out by al-Qaeda – the more reinforced the idea becomes. Citing science and media reports to someone who doubts science and the media will only prove to them that they’re right. It’s a feedback loop – or, as others call it, "the backfire effect".

Humans are riddled with confirmation bias – we look for evidence to support our beliefs, not to undermine them. Think of your social media use – more than likely it conforms to your political bias. Most people won’t deliberately search out information that could change their worldview.

In one study in America, test subjects were given literature for and against gun control and told they could read whatever they wanted. Psychologists asked them to be objective and look at both positions. Those who were for gun control read the pro-gun control literature, those against read the literature supporting gun ownership.

Conspiracy theories selectively take information and knit it together with other disparate facts – ignoring anything which undermines the narrative. Take the "Birther" conspiracy theory that Barack Obama was actually born in Kenya, not America. When Obama released his birth certificate to show the claims were lies, it only fuelled the conspiracy as Birthers claimed to see flaws in the paperwork further validating their beliefs.

The bigger an event – the more likely it will attract a conspiracy theory. As Brotherton says there’s really no conspiracy around the shooting of Ronald Reagan – because he survived. But the assassination of JFK spawned countless conspiracies. "We are guided by a mental shortcut called the ‘proportionality bias’," he says. "We want the magnitude of an event to match the magnitude of whatever caused it."

Of course, all this doesn’t mean that there’s no such thing as a real conspiracy. From the work place to Westminster, people are conspiring against each other for money, love and power. But what separates those conspiracies from conspiracy theories is that your next door neighbour plotting to run off with your partner isn’t a grand plot against humanity.

However, there have also been real nefarious government plots which have been deeply against the interests of citizens and wrapped in cloaks of secrecy. Just think of Watergate.

"Given what we know about the FBI illegally spying on anyone they considered subversive, military plans to assassinate foreign leaders and innocent civilians, and recent revelations about the National Security Agency’s unprecedented snooping abilities, we can all be forgiven a little prudent paranoia," says Brotherton.


I took the famous Heider and Simmel experiment and posted it on social media the other day. The experiment involves a one-minute film of three shapes – a big triangle, little triangle and little circle – moving around the screen. In the original experiment in the 1940s only one participant gave the correct answer when asked what they’d seen. It was a woman and she said she saw three shapes moving around in various patterns. Everyone else saw a "story".

At the time of writing, nearly 90 people responded to my posting asking them to tell me what they thought they’d seen.

One person saw a robbery, many saw domestic violence or bullying. One saw sharks breaking into a dive cage, another a fish defending its nest. People were emotionally invested – some expressing outrage, upset and fear.

When I did the experiment – without knowing what the outcome should be – my imagination created a scenario a bit like the Hansel and Gretel story.

Only two people recognised it for what it was – shapes moving in a pattern – suggesting we will generally make up a story where there is none: perhaps, the key to why humans are so drawn to believing conspiracy theories.

What do you see when you watch the clip?


I’M one of the least likely people you would ever think to call on to defend the royal family. Let’s say I’m not much of a monarchist. But back in Russia in the late 1990s, I found myself a lone voice defending the Queen and Prince Philip against the charge of murder.

It was the winter of 1997, and I was on assignment in St Petersburg as a reporter. As a newly arrived journalist, I was asked on to a late night radio show to talk about current affairs.

Everything started well in the Green Room and then we got into the studio. Attention soon turned to the issue of Princess Diana – who’d died just months before.

"What do you make of the Diana affair?" I was asked.

I said the entire episode had been as if Britain had a collective breakdown. I felt sorry for the dead woman and her family, but also quite alienated by the national outpouring of emotion.

No, that’s not what what I mean, the questioner said. Who do you think killed her?

We were live on air and I didn’t want to be rude, so I calmly said that she hadn’t been killed. She’d died in a car accident.

Then people started to laugh at me: my translator was laughing, the other guests, the host – everyone was laughing at me.

"Are you a stooge for the British state? For MI6?" I was asked.

I’d never been more offended in my life. Of course not, I said, I’m a reporter, telling you the truth.

"So Prince Philip did not have Diana murdered?"

No, I said. One hundred per cent no.

There was a collective sneer in the studio and for the remainder of the programme no-one else asked me a single question.