Every so often, our editorial team receives an email from someone claiming they’re being attacked by microwaves or controlled through a microchip in their skin. Should we take such claims seriously?

These concerns should certainly be taken seriously. Whilst the overwhelming majority of conspiracy theories aren’t literally true, they may well point to an actual problem. In the cases you’ve mentioned there may be tangible psychological problems which have led to a state of paranoia. But conspiracy theories where an individual doesn’t feel personally threatened, but rather has the feeling that the established order of their country is in jeopardy, may in fact point to a crisis of representative democracy or a fear of loss of status.

How would you define a conspiracy theory?

Fundamentally, a conspiracy theory hinges on the premise that a covert group is attempting to usurp, or indeed has usurped, the established order with a view to harming, controlling, terrorising or even destroying an institution, country, or the entire world. Another defining characteristic is that of a group negotiating in secret and pursuing a given plan - if there’s no plan then there’s no conspiracy.

We’ve recently witnessed the NSA scandal and Russia’s supposed interference with the US elections. Are conspiracy theories enjoying a renaissance?

Conspiracy theories have seen a resurgence in visibility over the last few years. Up until a few decades ago, they were even more popular in Europe and the US than they are today, and were often regarded by mainstream society as legitimate. People later became more sceptical, and conspiracy theories were pushed to the margins, retained by some sub-cultures but out of the spotlight.

Twenty or thirty years ago, if someone wanted to spread a conspiracy theory, they had to publish their own book outlining their ideas, which didn’t usually attract many takers. Today, of course, the internet makes dissemination a lot easier and quicker.  It’s this visibility which has breathed new life into conspiracy theories.

Another important factor is that, in many countries, society has fragmented into sub-groups and counter-groups. In the mainstream world in which most journalists and scientists operate, conspiracy theories are still stigmatised. But among certain groups, conspiracy theories retain the same status they had a few decades ago.

What is the function of conspiracy theories?

Conspiracy theories offer an explanation. Many people find it easier to accept that there are evil forces controlling everything than the idea that no-one is pulling the strings. At the same time, people who believe in conspiracy theories, and especially those who elaborate and share them, claim they’re going against the grain – they’re the ones who really know what’s going on.

Of course, identifying the guilty party gives rise to scapegoating. It means I can point the finger at someone, and perhaps even defeat them. Conspiracy theories usually contain a glimmer of optimism, as it’s conceivable the conspiracy will not just be unmasked but also shot down.

A study by Dartmouth College shows when people are confronted with evidence against their conspiracy theory, their belief in the theory actually increases. 

That’s the pull of conspiracy theories. If Pegida supporters go out onto the streets and protest against everything that’s changing in Germany – from the neo-liberal economic order to equal rights for homosexuals and the naked truth that not everyone they pass in the street is white – and then say that all this is down to large-scale structural changes that no one in particular is responsible for, then there’s no chance of anything changing. But if they say that it’s all a setup, that the influx of migrants has been manipulated, that gender mainstreaming is part of the conspiracy, etc., then at least there’s a possibility of everything returning to the way it once was.

Can conspiracy theories be debunked? Whenever they’re challenged, new explanations surface to keep the original theory alive. 

That’s a key characteristic of conspiracy theories and it’s an accusation often levelled against them. It’s also what separates them from ‘real’ theories: they aren’t refutable. Conspiracy theorists can always transform evidence against the conspiracy into evidence for the conspiracy. An example: 2,000 architects say the World Trade Center couldn’t have collapsed just because two planes flew into it and therefore must have been blown up from inside. You say they’re telling the truth. But then 200,000 architects say that that’s complete rubbish. You reply that they’re lying because they’re part of the system and that they either don’t want to face the truth or are being paid to spread lies. This means that you can use both the argument and the counterargument to support the conspiracy theory.

There’s even a study by Dartmouth College that shows when people are confronted with overwhelming evidence against their conspiracy theory, their belief in the theory actually increases. 

The Turkish government has accused the Gülen movement of initiating last summer’s failed putsch. Tens of thousands of civil servants, allegedly with links to the movement, have since been fired. How can we differentiate verifiable facts about the movement, which does actually exist, from the conspiracy theories?

I’m not really in a position to judge, but what is remarkable is the fact that, at a time when it could not possibly have been able to provide any evidence, the Turkish government came out and said that it was all a Gülen conspiracy and used this accusation for its own political ends.

So, it seems it’s not only powerless citizens that create and believe in conspiracy theories but also decision makers and powerful politicians.

There’s nothing unusual about that. What is more unusual is that over the last twenty years, conspiracy theorists haven’t held power in Germany, France or the US. As long as conspiracy theories are seen as legitimate by the mainstream, they will always be bandied about by the powerful, even in the Western world. Every American President, from George Washington to Dwight D. Eisenhower, was a conspiracy theorist and there’s plenty of evidence to support that assertion. So Donald Trump is not an exception, he’s basically just a return to the former mould.

Every American President, from George Washington to Dwight D. Eisenhower, was a conspiracy theorist.

Outside of the Western world, including in Eastern Europe and the Middle East, conspiracy theories have remained a tool for the exercise of power. This was certainly the case in Iran under President Mahmoud Ahmadinejad. We see it today in Russia and Turkey too. What’s difficult to ascertain in each individual case is whether the theories seek to cynically instrumentalise a situation and those involved know that it doesn’t add up, or whether the people who come up with the theories actually believe them. US Senator Joe McCarthy is a fine example of the latter. He tapped into the theory of the Communist infiltration of America for so long, he convinced himself the infiltration had in fact taken place.           

What’s the best way to address conspiracy theories?

I don’t think that there is a best way. Some say you shouldn’t enter into a discussion with those spreading racist, sexist or anti-Semitic conspiracy theories that push the bounds of what society finds acceptable. But is it really good to have a society that’s so fragmented, it’s impossible to hold a conversation. So I generally think it’s important to stay engaged and show that you take people’s concerns seriously, even if you don’t believe everything that you’re hearing.

Here’s what I do – I receive quite a lot of mail, including from conspiracy theorists. Some messages are very offensive, so I don’t reply. But if someone writes me a polite email, I respond by saying: ‘Thank you very much for contacting me. First of all, let me say that I see things a little differently’. I then write ten lines, and they usually write ten pages back to me an hour or so later. I often don’t have time to go through all the finer points but I at least write back to them saying: ‘I’m sorry. I really don’t have the time to write back to you’. Often the response is very positive.

We also need to tell people, through education and training, about how conspiracy theories work and why they mostly don’t reflect reality but distort it. We should also encourage people to think critically.

What’s been the most successful political conspiracy theory?

The most successful conspiracy theory – in its different articulations – is probably the anti-Semitic conspiracy theory. In Germany, it brought a regime to power that ruled for a long time, with the disastrous consequences that we’re all familiar with.