I was lucky enough to have been taught history by a teacher who was years ahead of his time. He drilled us to test and question evidence. We were to accept nothing at face value and weigh up who was saying something and why.

Contemporary sources were to be treated with particular caution; what did the writer stand to gain or lose? Secondary sources commenting on historical events had to be tested for rigour and bias. As apprentice historians, we were expected to seek alternative pieces of evidence, even if they inconveniently conflicted with our earlier conclusions.

It was a thorough grounding at a time when nearly all evidence was in print. The process wasn’t infallible. In the early1980s, the forged Hitler Diaries initially fooled historians and newspaper editors alike. If filtering historical and political fact from fiction was challenging and important then, it’s even more vital now.

The internet spews out an indigestible diet of “data” and “evidence”, much of it of doubtful provenance. In the print-dominated past, getting ideas and theories to a wider audience was a challenge. Sure, you could get on your soapbox at places like Speakers’ Corner, but your reach would be minimal.

Getting into print in newspapers, magazines and books was a challenge that filtered out most off-the-wall theories and positions. Even if printed, they would be subject to further close scrutiny and professional appraisal.

In contrast, technology provides anyone with a keyboard access to a worldwide audience, irrespective of how hare-brained they and their ideas are. Yet, it’s too easy to characterise and dismiss these keyboard warriors as social misfits, tapping away in their parents’ backrooms. They are an important and cumulative factor in the worldwide growth of insidious conspiracy theories, spread via social media and doing real and lasting harm.

My history teacher encouraged healthy scepticism of official narratives, but what we have at present is altogether different. Conspiracy theorists go beyond scepticism, following Alice down the rabbit hole into an illusory and irrational world.

True, we all have some irrational beliefs. I believe the Dons will one day reclaim the premiership title. Serious conspiracy theorists are even more irrational. Additionally, they tend to be angry, resentful and fearful of a world they no longer understand or feel part of. It’s easier to rationalise and make sense of complex and unsettling events if an external controlling hand is responsible. In short, these events are not happenstance; somebody made it happen.

The nature of conspiracy itself has also undergone transformation. We are familiar with images of traditional conspirators such as the Gunpowder Plotters; a handful of men huddled around a lantern and a plan. The exponential growth of present-day conspiracy theories parallel the growth of companies and institutions with worldwide reach. Conspiracy becomes more credible through the secrecy surrounding state intelligence and security agencies and “plausible deniability”. Who really shot JFK? Did the CIA play any part in downing Pan Am 103? What is the truth about 9/11? More mundanely, was there a conspiracy to blacken the name of a former Scottish first minister?

Covid has supercharged belief in conspiracy. Pandemic deniers and anti-vaxxers have climbed aboard the raft of theorists that bobs around at the margins of rationality. Within our circle we have someone steadfastly refusing to wear a mask or be vaccinated because Covid “is a hoax” and the vaccine carries a chip allowing “them” to track our movements.

The same person believes Hilary Clinton is dead and President Biden’s inauguration was faked. Opposing points of view are met with the response, “Go to the internet and LEARN!” The BBC has attempted to counter similar arguments by appointing Marianna Spring as its first specialist disinformation correspondent. She has gone public to share the level of abuse she experiences. She’s been told, “You’re the equivalent of Josef Goebbels”, called a “paedophile worshipper” and threateningly warned, “I hope you get what’s coming to you”.

Few would dispute genuine conspiracies did and do exist. Richard Nixon’s cover-up of Watergate and the infamous “Dodgy Dossier”, justifying the invasion of Iraq, to name but two. Some would argue the recently leaked Pandora Papers uncovered a conspiracy by international finance on an almost unimaginable scale.

These, and other events, in which there may be grains of truth, make it more difficult to debunk the extreme and absurd theories such as those surrounding the Sandy Hook school massacre and the nonsense perpetrated by QAnon.

The strength of conspiracy theories is demonstrated by their ability to survive and mutate even in the face of evidence and powerful arguments to the contrary. They are resistant to the truth vaccine. As Josef Goebbels was well aware, the bigger the lie and the more often it’s told, the more likely it is that it will be accepted as the truth.

Conspiracy theorists are not necessarily ignorant. They can be well-read and informed, the problem being where they get their information and how capable they are of sifting out the garbage. They are certainly not harmless. The constant drip of misinformation undermines established positions on vital issues such as climate change and vaccination.

Research suggests conspiracy theories foster a sense of powerlessness and make it less likely people will take personal action or even vote. In his book, Escaping the Rabbit Hole, Mick West emphasises the importance of engaging with conspiracy theorists, but not via social media. Discussion should be based on fact, logic and respect.

By that time however, it may be too late and misplaced beliefs will have become resistant to change. Conspiracy theories need to be addressed before they become embedded. We urgently need more inspirational educators, like my 1960s history teacher.

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