After persisting as a fringe movement for decades, the belief that the Earth is actually flat, and not a globe, suddenly experienced a massive spike in popularity in early 2015.

It drew tens of thousands of people into various Facebook groups, spawned countless memes and YouTube videos, caught the eye of minor celebrities, and even inspired reasoned and nuanced takedowns from popular science communicators like Neil deGrasse Tyson, who called Flat Earth "a deep failure of our educational system."

To be clear, none of these videos or memes present any compelling evidence that the Earth is actually flat.

Most rely on constant repetition of the claim that "you can't see the horizon" and on obfuscating debate by misusing an unending stream of scientific jargon like "crepuscular rays" and "gyroscopic attitude indicators." When that doesn't work, they just claim every photo of a "globular" Earth was either distorted by a fisheye lens, or faked by NASA.

When confronted with the fact that a flat Earth is actually impossible because of the scientific principle that the bigger a flat disk is, the more distorted the gravity becomes away from its center, many flat Earthers double down. They claim that gravity itself is also a hoax, and the flat Earth is accelerating upward, propelled by "universal acceleration." 

The further one delves into flat Earth, the more technical and jargon-heavy the explanations for it become. This is a common trait of conspiracy theories, which disregard simple and oft-proven explanations in favor of a torrent of dubious ones. Defeating the fallacious arguments individually is possible, but after a while, the effort becomes tiresome, and the skeptic moves on, allowing the believer to claim victory in absentia. 

A survey of these Facebook groups by ATTN: found that specific flat Earth beliefs are almost entirely intertwined with conspiracy theory beliefs as a whole, which is consistent with established research showing that if you believe one conspiracy theory, you're likely to believe others, even if they contradict. One groundbreaking 2012 study found that people who "believed that Osama Bin Laden was already dead when U.S. special forces raided his compound in Pakistan, [also] believed he is still alive."

It's this conspiratorial construct that powers much of the modern flat Earth movement. Spending time engaging with flat Earth social media, including watching popular YouTube videos, ATTN: found a mix of sincere belief that the Earth is flat, but almost as much trolling from "globalists" (the main flat Earther term for those who believe the Earth is round), and numerous other theories about 9/11, evolution, climate change, and Jews. 

Pinterest - pinterest.com

Flat Earth Memes - whotfetw.com

Flat Earth Memes - whotfetw.com

ATTN: reached out to a number of Flat Earth Facebook group members for comment on their beliefs, and received mostly ridicule and circular arguments in response. 

Flat Earth Society/Facebook - facebook.com

Official Flat Earth & Globe Discussion/Facebook - facebook.com

But even while they might not want to discuss it objectively, what Flat Earthers believe, and how they express their beliefs, can teach a great deal about the nature of conspiratorial thinking. Why are people are so inclined to believe things that are clearly wrong, but that fit in with their belief systems? As science, it's entirely discredited. But as a movement, it's a fascinating look at human nature. 

The Flat Earth movement has gone through several incarnations over the last century, and its current form barely resembles its origins. Contrary to popular misconception, neither ancient nor Middle Ages people believed the Earth was flat. Nor did Christopher Columbus. As early as the fifth century BCE, the ancient Greeks knew the Earth was a globe, though they didn't know how big it was.

Flat earth mythos was mostly the stuff of pop urban legend until the late 1800's, when a book called "Zetetic Astronomy: The Earth not a Globe" articulated the claim that the planet was a flat disc surrounded by ice walls. That book spawned a debating society that morphed into the International Flat Earth Research Society in the 1950s. That group morphed again into a non-scientific Christian fundamentalist conspiracy mongering group, and then into an online only forum, which now has about 11,000 members.

While the official Flat Earth Society is devoted almost entirely to backstopping flat earth beliefs by way of the Bible, the numerous other flat Earth Facebook groups like "Flat Earth Society," "Official Flat Earth and Globe Discussion" and "Flat Earth - No Trolls," are just as likely to spend their time pushing random memes, general conspiracy theories, and blanket questioning of accepted scientific principles as they are to discuss whether the Earth is flat or round. 

One word, "globalists," truly becomes the key to understand Flat Earth, because like many conspiracy theorists in general, many flat Earthers are virulent anti-Semites.

While overt anti-Semitism is kept out of most Facebook groups, it's all over Flat Earth message boards and in the use of that term, globalist. As Peter Hess writes on Inverse, "The casual observer may think the word “globalists” [by flat Earth believers] is simply shorthand for people who believe the Earth is a globe rather than a disc, but it actually has a long, racially charged history. In modern use, it’s used as a dog-whistle term for Jewish people."

Finally, it's here that we find the crux of the Flat Earth movement. It's not about the Earth actually being flat, because even the most rudimentary scientific techniques tell us it's not. It's about "questioning everything" and not believing anything you can't see with your own eyes. If you can't see the curve of the Earth, it's not real. If you can't see gravity, it's not there.

This ethos leads to an almost endless series of debates over the veracity of virtually every facet of science, technology, politics, and history.

After all, if the globalist bankers who run the world could get away with inventing a round Earth, what else are they lying about?