In 331 BC, something was wrong with Rome. Across the city, swathes of eminent men were succumbing to sickness, and practically all of them were dying. The losses were as baffling as they were alarming.
Then one day, a slave approached a curule aedile – a kind of magistrate – and hinted that she might know why. The girl led a team of investigators to various houses, where she claimed they would find an alliance of upper-class women secretly preparing poisons. They did.
The accused were dragged to the central square, and asked to prove their innocence. Since they claimed their concoctions were medicinal, would they drink them?
Alas, two of the suspects obliged – and promptly dropped dead. Mass arrests followed, and a further 170 women were found to be involved. The incident was a huge scandal. In the aftermath, the people of Rome elected a dedicated official to perform a ritual banishment of evil, a tactic which had previously only been used as a last resort after extreme civil unrest.
Or, at least, this is the version of events that was dutifully recorded by the respected historian Livy, who was born a few hundred years later. But he wasn’t convinced that the women were really responsible, and neither are modern-day experts. Instead, Livy pointed to a far more rational explanation: an epidemic.
At the time, the city was in the grip of an unknown plague – a common cause of death in the classical world. Mass poisonings, on the other hand, were unheard of. The case discussed by Livy was the first of its kind, and the whole affair had struck Roman citizens as distinctly odd.
In fact, the women probably really were preparing medicines – and the rest of the story was heavily embellished or entirely made up. The infamous poisonings of 331 BC are thought to be a conspiracy theory, to explain deaths that had an obvious cause all along.
Amid the current pandemic, this scenario is oddly familiar. Since the beginning of April, at least 77 phone masts and 40 engineers have been attacked in the UK, after some people bought into the erroneous idea that Covid-19 is somehow being spread by powerful forces in the global telecommunications industry. Now the rumour has spread to the US, where there are fears it may lead to further violence. Yet again, reason is being cast aside, in favour of a niche explanation that involves a convoluted secret plot. (Find out why 5G is not responsible for transmitting Covid-19.)
The question is, why did these alternative stories catch on?
The Romans viewed slaves and upper-class women with suspicion (Credit: Alamy)
From alien lizard rulers to shark attacks instigated by spies and elaborate multi-billion-dollar hoaxes, the menagerie of conspiracy theories in existence is so bizarre, the reasons some take off – and others vanish without a trace – may seem almost random. There’s even a conspiracy theory about how conspiracy theories were invented (in keeping with the standard conspiracy formula, the CIA were allegedly involved).
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But there are patterns hidden in their strangeness. The latest thinking suggests that conspiracy theories are filtered by a kind of natural selection, which allows those that fit certain requirements to spread rapidly through our societies – while others are confined to the darkest corners of the internet.
What makes a conspiracy appealing to the masses? And is there anything they can teach us about the problems we face – and how to fix them?
First up – successful conspiracies always have the right villain. Throughout history, many widely accepted conspiracy theories have conveniently placed the blame for distressing incidents or trends on the population’s favourite baddies.
According to an analysis by Victoria Pagan, a classical historian at the University of Chicago, the success of the Roman poisonings conspiracy is likely to be partly down to the way it portrayed upper-class women and slaves, who powerful male elites found threatening.
Though the civilisation relied heavily on the exploitation of both these groups, men were constantly worried that their subordinates would turn on them. High-status women were generally viewed with suspicion, and often portrayed as secretive and dangerous. Slaves, on the other hand, had been known to murder their masters from time to time – and there was a long-standing paranoia that they sometimes acted as spies, and so couldn’t be trusted.
In short, a conspiracy involving a gang of murderous women being betrayed by their slaves was ideal – it was always going to be more appealing than the truth.
Meanwhile, in the modern world, it’s no accident that popular conspiracies tend to concern themes such as alien life, religious minorities, powerful elites, rival nations, mysterious technologies and the destruction of the environment. “Across the world, people generally believe in theories that are related to the cultural and historical events that have happened in particular places,” says Karen Douglas, a social psychologist at the University of Kent.
Each society has its own anxieties and obsessions – and successful conspiracy theories generally tap into them. Take Romania, where many women decline to have their daughters vaccinated against HPV, the virus responsible for 99% of cervical cancers.
Successful conspiracy theories generally tap into a society's anxieties and obsessions (Credit: Getty Images)
In 2008 – the first year the vaccine was offered – just 2.5% of eligible Romanian women had it. The rates were so low, the school-based vaccination programme was eventually abandoned altogether. This is particularly surprising, when you consider that elsewhere in Europe, the HPV jab is extremely popular, with uptake at around 80% or higher, and that the nation has a long track record of having the highest fatality rates from cervical cancer on the continent.
There are several reasons for Romanian mothers’ suspicion of the vaccine, but research has shown that one is the abundance of conspiracy theories about the true motivations for providing it, including the idea that it’s an attempt to control the world’s population by making women infertile and that it’s a medical experiment by the pharmaceutical industry – though there is no evidence for either.
These, in turn, may have been fed by the country’s history of meddling with women’s fertility, along with a general lack of trust in the healthcare system; it’s still common for patients to bribe medical staff for even basic care, and many of the women in the study reported suspicion about why the vaccination programme was free of charge.
In some cases, it’s thought that concerns like these remain dormant in our minds, until certain events – such as political change – activate them. This can lead them to fuel our collective belief in conspiracy theories.
Anti-Semitic theories – such as the idea that Jews are powerful and engaged in secret evil plots – have historically emerged during times of societal stress, such as periods of unemployment – possibly because they allow people to consolidate blame for what can be the result of a complex set of societal and economic circumstances instead on a single scape-goat. Research has shown that people who have a social identity centred around victimhood are more susceptible to conspiracy theories that villainise Jews, and this might also be true at a societal level.
This fits with another common ingredient in popular conspiracies – they make us feel good about our own social group, often while putting down those we see as our rivals. “That can be your national group, or your gender group or whatever,” says Douglas. “There’s some evidence that people are attracted to conspiracy theories that satisfy these prejudiced attitudes.”
By emphasising the distinctions between “ingroups” and “outgroups”, conspiracy theories may also lead to stronger social bonds – and provide a sense of protection against those people find threatening. Accordingly, conspiracy theories are often widespread in groups that are involved in mutual conflict.
In Romania, there is a general lack of trust in the healthcare system, which might explain the abundance of conspiracy theories about the HPV vaccine (Credit: Alamy)
“There is some research to suggest people turn to conspiracy theories more when they're confronted with crisis situations,” says Douglas.
The idea that 5G and other earlier mobile phone networks are somehow bad for our health has been around for years – ever since the technology entered widespread use around 30 years ago. To begin with, it was falsely accused of being responsible for causing autism, infertility and cancer, among other things – but generally confined to the most hardcore conspiracy theorists.
The emergence of a mysterious new coronavirus in December 2019 set the stage for a new slant on this enduring idea. On the 22 January – when the virus still had infected just 314 people, leading to six fatalities, an article was published that changed everything. It was an interview with obscure family doctor in a Belgian newspaper, and titled “5G is life-threatening, and no one knows it”. Crucially, it linked the dangers of 5G to the new coronavirus even though there is no evidence to support the claim. And that was it.
“Conspiracy theories tend to emerge quite quickly when something important happens,“ says Douglas. “They come out of the blue when there's some kind of crisis or conflict that people really want to explain and want to have answers for.” She points out that the recent bushfires in Australia also led to a number of trendy conspiracies.
There’s this effort by politicians to erase facts and evidence and remake the world into something more conducive to their goals – Russell Muirhead
The 5G theory has been called a “conspiracy cocktail”, since it involves several of humanity’s greatest fears, shaken together in one deliciously appetising mixture. As well as the perennial fear of new or invisible technology, which seems to pervade many popular conspiracy theories, it also taps into an undercurrent of anxiety about the emergence of China as a global superpower.
Another reason the 5G conspiracy might be more appealing than the truth is that it’s a story. Fairy tales, legends, anecdotes and gossip are how our brains make sense of the world – they go back tens of thousands of years, and they’re arguably what makes us human. In times of crisis, it’s possible that we turn to conspiracies because we find them reassuring.
Conspiracy theories have all the elements of a good story – terrifying villains, creative plots, and moral lessons. Because of this, a well-constructed conspiracy can have a powerful hold on the public imagination, in a way that a narrative about a “virus emerged entirely unpredictably and killed thousands for no reason” is unlikely to be able to rival.
Some psychologists have compared conspiracy theories to religious beliefs, in the way that they help us to feel more in control, by taking unpredictable or random events and making them seem somehow predestined or shaped by human hands.
Others have gone so far as to suggest that this is why they stick: in their content, storylines and purposes, they come uncannily close to the beliefs perpetuated by many organised religions. Some people believe in conspiracy theories to such an extent that they will even put their lives on the line, in their attempts to prove themselves right.
It's thought that people are more susceptable to conspiracy theories during a crisis (Credit: EPA)
Similarly, leading conspiracy theories often address some kind of ambiguity or mystery, from unexplained plane crashes to sudden celebrity deaths.
Where the authorities either can’t or won’t provide more information, these knowledge gaps combine with a general mistrust – driving the public straight into the arms of those who claim they have the answers. This is compounded by the fact that science, government inquiries and other legitimate forms of information-gathering can be painfully slow, in the meantime leaving a temporary void in which other sources can become established.
After the disgraced scientist Andrew Wakefield falsely claimed that the MMR vaccine can lead to autism in the 1990s, it took decades of research to establish beyond reasonable doubt that this had absolutely no scientific basis – in which time, the conspiracy had time to do serious damage.
Eventually, conspiracy theories can become so popular that they enter a positive feedback loop, in which the more they’re discussed, the more legitimate they seem.
For example, a recent analysis of Tweets that mention 5G and Covid-19 found that just 34.8% included a suggestion that the two are linked, while the majority either denounced the theory or didn’t express an opinion. Unfortunately, whether the users were making fun of the idea or explaining why it’s false, they were still raising the profile of the idea.
Indeed, the advent of social media and the rise of new technologies have been big moments in the history of conspiracy theories. “Of course you will find more geographically localised conspiracies in certain countries that other people don't even know about,” says Douglas. “But it is true that the way that we communicate with people now and the way we consume information is much more global than it was before, so some conspiracy theories are just very, very well-known across the world.”
Some conspiracy theories, such as those that involve exclusive groups of people secretly running the world, are now ubiquitous, she observes.
As politics becomes more polarised, some experts think that it's becoming easier for conspiracy theories to take hold (Credit: Reuters)
As our societies are changing, so are conspiracies – and Russell Muirhead, a political scientist at Dartmouth College, New Hampshire, is concerned about the direction they’re taking.
“Classically, conspiracy theories are propagated by people on the margins – they’re almost a weapon of the powerless, for holding the powerful to account,” he says. “But right now the new stuff is coming directly from the powerful, which is really quite extraordinary.”
Since the Covid-19 pandemic began, numerous world leaders have announced their public support for related conspiracy theories, which often align remarkably well with their own agendas. For example, US President Donald Trump recently suggested he has seen evidence the coronavirus originated in a Chinese lab while his own intelligence agencies have said there is no evidence for this. Venezuelan President Nicolás Maduro has also claimed it’s the other way around – the pandemic was caused by a bioweapon that was unleashed on China (but again there is no evidence for this).
We are, Muirhead suggests, being manipulated by our own weapons. “There’s this effort by politicians to erase facts and evidence and remake the world into something more conducive to their goals.”
It's thought that a new type of conspiracy is emerging, which doesn't require any evidence or justification (Credit: Alamy)
The whole scenario is also being exacerbated by the fact that many countries, such as the United States, are experiencing record levels of political polarisation at the moment. “That’s kind of motivated this new conspiratorial talk,” says Muirhead.
He gives the example of “Pizzagate”, the entirely discredited and widely condemned conspiracy that linked former US presidential candidate Hillary Clinton’s campaign manager to an alleged child abuse ring in the basement of a pizza restaurant. Despite being entirely made-up, it gained widespread support in 2016, culminating in a man firing an assault rifle inside the business.
“This conspiracy doesn't try to explain anything about the world,” says Muirhead. “What it does do is paint Hillary Clinton, not just as somebody who [in some people’s opinions] is, on balance, less desirable than her opponent, but as the sort of human being who is worse than a Nazi.”
In the book “A Lot of People Are Saying”, which Muirhead co-authored with the political scientist Nancy Rosenblum from Harvard University, he introduces a second new trend in the conspiracy world: conspiracy without the theory.
“Not only were there no children being held captive at the pizza restaurant, there wasn’t even a basement,” says Muirhead. “What surprised us was the way this narrative was a complete fabrication, from beginning to end.”
He explains that normally conspiracy theories would start with a kernel of truth – an event in the real world that’s easy to see and hard to understand, like an assassination or an attack – and build on it. But the latest generation of conspiracies skip this first step and seem to be successful regardless of how blindingly obvious it is that they’re false.
“I'm worried that ordinary people trying to understand the world are going to become very disoriented as they try to navigate this kind of whiteout blizzard of conspiratorial fictions and lies,” says Muirhead.
The "Pizzagate" conspiracy gained widespread support in 2016, despite being entirely made-up (Credit: Reuters)
So what should we do about it?
“We can’t just take on the conspiracy charges one by one by one,” says Muirhead. In his view, part of the problem is that people have gradually lost trust in experts, governments and powerful institutions. To fix the system, he suggests that we need to re-legitimise democracy – reform our governments and retrain our institutions. “In the United States that was done in the early decades of the 20th Century. It rehabilitated the government for new generations, and led to all sorts of progressive reforms, culminating in female suffrage.”
Douglas, on the other hand, thinks more research is needed. “I think it is really, really important to understand where conspiracy theories come from and how they spread, because there’s strong evidence that believing them has significant consequences.”
In particular, she explains that there have been very few studies into why some have extraordinary longevity, such as the Flat Earth, Illuminati and Moon Landing conspiracies, while others die out relatively quickly – though this is something she is starting to look into.
In fact, despite decades of research and an endlessly captivated public audience, there are still many unanswered questions in the field. “I think there's a general consensus amongst researchers that we are in an age of conspiracy, but again, there’s no real evidence for that,” says Douglas.
Who knows, perhaps that could be the next conspiracy…
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