This week, the online pollster YouGov released a survey of 8,215 American adults who were asked if they believe the Earth is flat, a ridiculous and obviously false conspiracy that has become a weirdly durable movement in the past couple years. YouGov found that 84 percent of respondents "always believed the world is round," 5 percent used to be sure the world was round but have begun to doubt it, 2 percent used to be sure the world was flat but now have doubts, and 7 percent clicked the "other/not sure" box.
More alarmingly, only 66 percent of 18- to 24-year-olds always knew the world was round, a hell of a statistic to contemplate when thinking about the future of the planet, whatever shape you imagine it is.
In one sense, this wasn't surprising—surveys that ask basic questions are always coming up with facepalm-y results, like the one from last year that found that 7 percent of US adults thought chocolate milk comes from brown cows or the 2012 poll that found that a quarter of Americans thought the sun goes around the Earth. But I mean, come on. Maybe people got nervous taking the poll and flubbed a response, maybe they were goofing around or trolling, maybe they started having doubts about the shape of the Earth or chocolate milk precisely because a pollster was asking about it. In the case of the YouGov survey, who knows why so many people clicked "other/not sure"?
It's worth noting, too, that there were a lot of lousy headlines about this survey that asserted that "A Third Of Millennials Aren’t Sure The Earth Is Round" or "Only Two-Thirds Of American Millennials Believe The Earth Is Round." Millennial no longer means "young person," for one thing (shoutout to my fellow old millennials), and for another, a whopping 16 percent of that young cohort clicked "other/not sure," meaning who knows what they thought? (Only 4 percent of under-25s have always believed the world is flat, a percentage that surely includes some trolls.)
That doesn't change the fact that flat Earthers are somehow real people. Rapper B.o.B. made the theory popular. People are shooting themselves out of homemade rockets to "prove it." Even Kyrie Irving, a basketball star with the resources to hire an expert on the topic, apparently buys into the theory. What the hell is up with that?
Believing the Earth is round means relying on sources. Most people haven't sailed around the world like Magellan or looked upon it from space or sorted out the relevant math involved in tides, gravity, and so on. The Earth's roundness is something we feel we know because we're confident that every reputable expert from the ancient Romans onward can't possibly be wrong. The thing is, confidence in experts is eroding—people don't trust institutions or experts as much as they used to, and they really don't trust the media. At the same time, some internet algorithms, like YouTube's "related videos," seem to point people to information that is more extreme and potentially less reliable.
Just as an experiment, just now I googled "is the Earth round" on Chrome's Incognito mode and clicked on the first video that came up—an explainer from popular YouTube channel Vsauce that shows that yup, the Earth is round. But it took me only two quick clicks on the right rail to end up at "Worlds Beyond The South Pole (Hidden Lands?)," a low-quality, almost nonsensical 21-minute video that nevertheless has more than 200,000 views; the channel that posted it, apparently run by some guy named "Jayson," has 10,000 subscribers and loads of that sort of video. How many of those sorts of things do you have to watch to flip from "always believed the world is round," to "not sure/other"? How many people have gone down that particular rabbit hole? And how the heck do we pull them back up from it?
Correction: An earlier version of this article said that a poll found a quarter of Americans thought the Earth orbited the sun when in fact it was the other way around.
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