There can be few basketball fans who would dispute the proposition that Kyrie Irving, the point guard with the Cleveland Cavaliers, is a genius on the court.
That, at any rate, was the theme of an article in The Undefeated this week, in which Irving's peers lined up to laud his talents. "His biggest asset," as Atlanta Hawks forward Paul Millsap put it, "is his creativity".
Perhaps. But having a basketball mind is not the same as possessing real-world perspective, it seems. Last month, Irving made headlines when he demonstrated another sort of creativity, revealing that he believed that the Earth was not round, like a basketball, but flat like a pancake.
“This is not even a conspiracy theory,” he said during a podcast for a sports channel. “The Earth is flat, it’s right in front of our faces. They lie to us.”
The four-time NBA all-star's revelation cast light on his contribution to The Undefeated article, in which he credited his skills to "a ton of practice, but also having an imagination that is sometimes out of my world".
Indeed. But the extraordinary thing about Irving’s denial of reality is that he is far from being alone. Other celebrities, including the rapper BoB, who has more than two million Twitter followers, and former MySpace reality star Tila Tequila, have also recently emerged as flat-Earthers.
The spherical nature of the Earth has been beyond dispute since Spanish explorer Juan Sebastian Elcano completed the first known circumnavigation of the globe in 1522 - an expedition initially led by Portugal’s Ferdinand Magellan - without falling off any edge.
Within six years, Nicolaud Copernicus had published his theory that the Earth and all the other planets in our solar system revolve around the Sun.
And yet, as a trawl of the internet and social media sites reveals, Irving is part of a growing army convinced that “They” are lying to us about the shape of the planet and, as a consequence, that everything we think we know about space, the stars and gravity is a lie.
There is nothing new about the flat- Earth theory – but now, thanks to social media, it is far more easily spread than it once was. The Twittersphere – or perhaps that should be Twitterplane – is home to a bewildering array of accounts, from Flat Earth Truth (“The Biggest Lie ever created. Learn the truth why the Earth is actually flat”) to Flat Earth Today, the official feed of the Flat Earth Society.
One of the theory's earliest advocates was Samuel Birley Rowbotham, an Englishman who in 1849 published a pseudoscientific pamphlet titled Earth Not A Globe.
In Rowbotham’s view, the world was a flat disc, bordered by an ice wall (Antarctica), a model that persists among his modern-day counterparts (many of whom claim Nasa’s real role is to stop the curious falling off the edge).
Rowbotham at least had the excuse that he lived in a time before human beings were able to soar in aircraft, let alone spaceships, and see the curvature of the Earth for themselves. Not so English signwriter Samuel Shenton, who founded the International Flat Earth Society in 1956, or Californian aircraft mechanic Charles K Johnson, who took over the society upon its founder’s death in 1972.
Johnson and his followers believed that "not a word of modern astronomy is true", as he declared in a 1978 edition of Flat Earth News.
In 1980 he told Science Digest that “people with common sense don’t believe idiotic things such as the Earth spinning around the Sun. Reasonable, intelligent people have always recognised that the Earth is flat”.
Today, his “reasonable, intelligent” successors claim to be able to counter all the “so-called” evidence that the Earth is a globe.
The inescapable observation that a departing ship disappears over the horizon? Optical illusion. The Moon landing in 1969? Faked in a studio. Photographs of a clearly round Earth taken by astronauts? Also faked, like the Moon landings. The curvature of the Earth seen through the window of a high-flying aircraft? Another optical illusion, or perhaps a plot by aircraft manufacturers in league with well, “Them”, of course.
What exactly have “They” got to gain by lying to us about the shape of the planet? There’s a lot of mumbling out there about the usual suspects – Freemasonry, New World Order and many others – but no real motive is offered.
“Nasa is controlled by the Illuminati elite,” suggests one flat-Earther online, “to keep you believing that you live on a sphere to make you believe you are all small and insignificant in the greater universe”.
It would be easy to dismiss the whole flat-Earth movement as a dumb joke.
As Craig Foster, a professor of psychology at the US Air Force Academy, wrote in The Denver Post this month, "people might comfort themselves by concluding that Irving is 'crazy' or 'stupid'."
But his belief in a flat Earth was “just another pseudoscientific development in a society that encourages this type of thinking. People and politicians frequently undermine science and science journalism by arguing that these groups are plagued with self-interest and deception”.
When Irving was subsequently asked by sports broadcaster ESPN whether he had seen photos of the planet taken from space, he replied: “I’ve seen a lot of things that my education system said was real that turned out to be completely fake.”
The result of such thinking is widespread, dangerous and ill-informed scepticism about everything from climate change to vaccinations. Post-truth, post-Donald Trump, it seems that anything, no matter how transparently preposterous, is possible.
At the heart of flat-Earthism lies that stock-in-trade of the social media age – conspiracy theorising.
Take this offering from the Instagram account FlatEarthshirtco in the wake of Irving’s revelation: “Irving says the Earth is flat. His comments go viral. Five days later, Nasa conveniently discovers seven new planets. It’s the government’s attempt at damage control – they don’t want people talking about the flat Earth.”
Are these people simply mentally unwell?
“There’s a range of personality and social factors – from paranoia and mistrust to education and political orientation – that have been linked to conspiracy belief,” says Karen Douglas, professor of social psychology at the University of Kent in southern England. “I wouldn’t say it’s a form of madness necessarily because most people subscribe to at least some kind of conspiracy theory.”
On the other hand, she notes, “[belief in a flat Earth] is a very interesting belief to hold in the face of so much evidence to the contrary”.
Belief in grand plots, says Daniel Jolley, a psychology lecturer at Staffordshire University in the UK and co-author of the blog The Psychology of Conspiracy Theories, serves a practical function in the psyche of modern human beings: “We want to feel in control of ourselves and our beliefs and, in essence, of the world around us – we want to feel certain. So when, for example, a plane goes missing, we feel out of control and uncertain, and the conspiracy theory gives us an answer and makes us feel more in control and more certain about our uncertain world.”
Not everyone, of course, turns to fantasy to make sense of our complex world. But while there is no one profile for the typical conspiracy theorist, says Dr Jolley, a poor standard of education, which causes a dearth of critical thinking, is often a common denominator.
“These people find a theory on a website,” he says. “They read about it but don’t think about the pros and the cons – they are not critical of the evidence. We need to teach children in schools that the top hit on Google isn’t necessarily going to offer the most accurate information.”
People seeking validation for their world view fall easy prey to what psychologists call confirmation bias – the tendency to interpret all evidence only in a way that supports their outlook.
“When a conspiracy theory becomes part of your belief system you then look for things that make sense of that belief and you disregard everything else,” says Dr Jolley.
In 1994, a poll for the Washington Post found that almost one in 10 Americans believed the 1969 Apollo 11 Moon landing was faked, a hoax that the Flat Earth Society's Johnson insisted had been exposed in the 1978 space film Capricorn One, which "proved the entire government space programme is a hoax".
One of the stars of that film was the American football player O J Simpson, who by 1994 was facing trial for the murder of his former wife, Nicole Brown. “They” were “finally going after O J”, Johnson said, “because he helped unmask the space hoax”.
What more evidence could one possibly need?
* This article was amended to clarify that Ferdinand Magellan did not circumnavigate the globe. The Portuguese explorer was killed in the Philippines in 1521 and the expedition was completed by Juan Sebastian Elcano.