Wilson da Silva

Science journalist, feature writer and editor.

Aug 1, 2009
Published on: Cosmos Magazine
1 min read

From wild speculation in financial markets to believing that aliens are visiting us, humans are incredibly prone to all sorts of personal and mass delusions – and have been for centuries.

By Wilson da Silva

WHY DO PEOPLE believe in phenomena such as UFOs, alien abductions, psychic surgery and ghosts, when the evidence is so scant and unconvincing? Why do some people insist there’s a ‘face’ on Mars when it has been shown to be a trick of the light, or that crop circles are alien artefacts when the pranksters who created these ingenious hoaxes showed how it was done?

Why do people persist in believing there was once an ancient advanced civilisation, now lost, known as Atlantis when scores of archaeologists say no shred of evidence exists? Or even that acupuncture and homeopathy can treat major ailments, when a wealth of reliable studies show otherwise?

We know human perception is prone to being unreliable: just listen to the testimony from different witnesses to a fire or a traffic accident and you’ll wonder if they are describing the same event. But why do so many people find themselves attracted to conspiracy theories, or the purported prophecies of a 16th century French apothecary Michel de Nostredame (better known as Nostradamus)?

Collective delusions do occur, and have done so throughout history: sociologists Robert Bartholomew and Erich Goode have detailed how false or exaggerated beliefs can often arise spontaneously, spread rapidly in a population, and temporarily affect a region, culture or a whole nation.

It’s often dubbed (inaccurately, as it turns out) ‘mass hysteria’, and many factors contribute to the rise and spread of such collective delusions.

These include rumours, extraordinary public anxiety or excitement, shared cultural beliefs or stereotypes, and amplification of these by the mass media, as well as reinforcing actions by authorities such as politicians, the police or the military.

Charles Mackay, the Scottish journalist and editor of the Illustrated London News, chronicled just how prone people can be to suggestion in his 1841 book, Extraordinary Popular Delusions and the Madness of Crowds.

And it’s clear that what he describes is not just a subject of academic interest or fodder for dinner party repartee: modern instances have destroyed jobs, companies and even economies. The global financial crisis, now reverberating through world economies, began with wild, unfettered debt everyone knew was unsustainable as it relied on borrowers to repay amounts that were clearly beyond their means. Was this not a mass, collective delusion?

In economic booms and busts, from which we have cycled into and out of so many times, we can see this very same delusional behaviour at play repeatedly. Mackay reminds us that it is disturbingly familiar: at the peak of the ‘tulip mania’ in February 1637, he wrote, tulip contracts sold for more than 10 times the annual income of a skilled craftsman, and at one point, five hectares of land was offered in exchange for a single Semper Augustus tulip bulb.

From the fruitless, centuries-long study of the transmutation of elements into gold, to the burning of witches in Salem; from the 17th century craze of using magnets to cure ailments, to the 200 year-long military campaigns of the Crusades and their far-reaching political, economic and social impacts – collective delusions have been a constant throughout history.

But they also play out individually, from tales of alien abductions – which are remarkably similar to accounts of demon abductions in earlier centuries – to reports of psychic surgery and the personal delusion that homeopathy cures ills. In some cases, they might be explained by an ailment we are only beginning to understand: sleep paralysis.

Maybe our limitations shouldn’t surprise us. “On the inside we are hunter-gatherers,” says physicist Robert Park, author of the book Superstition. “The brain that enables us to write sonnets and solve differential equations has changed little in 160,000 years. Science transported us to a world of jet travel and electronic communication with a brain still hard-wired with the instincts of savages who fought to survive in the Pleistocene wilderness.”

But there is hope: and it can be found in science. In The Demon Haunted World, the excellent 1995 book on critical thinking and the delusions that plague humanity, Carl Sagan argues that the scientific method and the clarity it brings can help us overcome our fuzzy thinking. Thinking critically and clearly, he says, “is the means … by which deep thoughts can be winnowed from deep nonsense.” He argues “it is far better to grasp the universe as it really is, than to persist in delusion, however satisfying and reassuring.”

Apart from the scientific method, Sagan offers a set of tools for critical thinking, which he calls the ‘Baloney Detection Kit’: construct a reasoned argument based on evidence and be open to recognising a fallacious or fraudulent one that contradicts evidence. Look for an independent confirmation of any facts and, all things being equal, apply ‘Ockham’s razor’: the principle that, in trying to explain a phenomenon, you should make as few assumptions as possible, since often the simplest explanation is the correct one.

He suggests ways of detecting “the most common fallacies of logic and rhetoric” such as accepting an argument purely because it comes from someone in authority, or believing someone who proffers statistics of small numbers. Ultimately, science is not an answer in itself; it’s the tool that helps you find the answers you seek.

Wilson da Silva is the editor-in-chief of COSMOS.