Confessions of a Science Anti-Troll

It started innocently enough when I wondered, "Does anybody really think the Earth is flat?"

Since this column is a confession, I’ll just come right out and say it: Sometimes I mix it up with flat-Earthers, especially on Quora, the popular question-and-answer site.

To be clear, I wouldn’t call these exchanges “debates.” There’s nothing to debate. It would be like debating “do humans have teeth?” or “air – real or not?” But I’ve engaged a lot more than once. A lot more than ten times, for that matter. Some of these exchanges have gone on for a while, and a few got me quite worked up.

When I started engaging with flat-Earthers (and their close cousins, the folks who swear up and down that the Apollo Moon landings never happened), I was looking for the answer to a question that had long gnawed at me: Why do they do it?

Some of the self-professed flat-Earthers are surely pranksters or social-media anarchists. Some of them seem to be people who crave attention or itch for the adrenaline rush of a bruising online fight. Some of them probably are trying to drive clicks, perhaps to build their online presence or to goose ad sales on their YouTube channels. In other words, a lot of trolls.

But some of these folks seem sincerely committed to a point of view that makes no logical sense and that requires rejecting obvious visual evidence about the world around us. They engage in extended disputes with people like me, who obviously are not going to be swayed by anything they have to say. They put a lot of time and effort into their obsession. Why do they do it?

As I kept engaging, though, I sometimes veered beyond my ostensible fact-finding mission and started posting answers to questions that were blatantly posed to provoke or stir outrage by us science-minded types. At which point I had to engage with another question: Why do I do it?

If I’m mixing it up with online trolls, what does that make me? An anti-troll?

I’ll admit that sometimes I, too, feel the adrenaline rush of engagement. There were times, early on, when I tried to confound flat-Earthers with an argument for which they had no answer. Those efforts almost always failed. (I say almost because I did see a couple Biblical-literalists waver when I pointed out that devout Jews and Christians overwhelmingly reject the notion that the Bible should be read as a geography textbook describing a flat Earth.) Then for a time I became fascinated by the responses I’d receive, including some truly baroque works of flat-Earth fan fiction.

Finally I did some soul searching and realized what was truly captivating me about these odd, often silly-seeming exchanges: They were sending me to go back to basics, all the way down to the epistemological foundations of science. They were forcing me to address the ur-question, How do we know what we know? And I loved it.

Intuitive Physics

It turns out that many key concepts are quite easy to investigate and demonstrate for yourself, with little or no equipment and with no particular expertise. In many cases, core concepts of physics are already etched into human intuition – just not necessarily in obvious ways when you think about them in unfamiliar contexts. I find it fun and enlightening to rediscover these basic truths firsthand.

Take, for instance, conservation of momentum. Quora is flooded with variants of this supposed gotcha flat-Earth question: “If Earth is rotating at 1,000 mph, why can’t I hover in a helicopter and watch the ground fly past me at 1,000 mph?” It’s the kind of puzzler that can flummox you for a moment, even if you recognize that the argument is flat-out wrong – in part, perhaps, because this kind of impossible action is a staple of cartoon physics.

The basic fallacy here is that momentum is conserved, meaning that you can’t just magically make it vanish. The solid Earth, the atmosphere, the helicopter, the pilot, everything, all share the same motion. Lifting the helicopter off the ground does not – cannot – make that momentum magically vanish. And intuitively we already all know this! If objects lost their shared momentum the moment they broke contact, then you could step out of a speeding car and touch down motionless on the side of the highway. Baseball wouldn’t be much fun, because the moment the bat lost contact, the ball would drop straight to the ground. If you dropped a bag of peanuts on an airplane it would shoot to the back of the plane at 500 mph. And so on.

What’s confusing here is that we live in a world full of friction, where the energy of momentum can be converted into heat and mechanical energy. Friction can make it seem as if momentum is leaking away into nothingness. Here too, though, we all intuitively understand that friction itself is what is causing the slowdown. When you roll a ball down a bowling lane, it keeps its momentum mostly unchanged all the way to the pins. When you roll a ball on a lawn, it rapidly comes to a stop.

Nobody imagines that the laws of physics change the moment you step into Bowlmor! You know what’s really going on. Momentum does not vanish for no reason. Physics is already coded in your head though years of familiar experiences.

Then there are the basic laws of perspective, which instantly falsify any flat-Earth model. The farther away an object is, the smaller it appears: That’s a basic rule of perception that we all learn in the earliest stages of childhood. It just becomes less obvious when you project that rule into the sky. Suppose you had no idea how far away the Sun and Moon are, how could you make an educated guess? It’s not hard!

Using nothing more than an outstretched finger for reference, you can watch the Moon over the course of a night, from rising to overhead to setting, and see that its apparent size does not change. If you have a pair of solar glasses (well worth buying – they cost about $2 and are great for watching the early and late stages of a solar eclipse), you can do the same with the Sun. The constant apparent size of the Sun and Moon means that either a) they are extremely far away or b) you are the lucky person who happens to be sitting at the exact center of the universe.

The next step is to call up a friend who lives a good distance away and have them do the same experiment. When they get the same result, you know that the Sun and Moon have to be much farther than the distance between the two of you. Pick a friend who is 3,000 miles from you, say, and you can confidently say that the Moon must be at least 5-10 times as distant, based on absolutely no external knowledge about the universe.

What about everybody’s favorite reductio ad absurdum, the shape of the Earth? How do you, personally, know that it’s a sphere? Suppose you don’t want to use any modern information (no satellite images, no GPS, etc) and figure out the shape of the Earth from first principles. You’re already halfway there from your perspective experiments. Talk to a friend who lives significantly to the west of you (or significantly to the east, just reversing roles). When you see the Sun set from your location, ask them where the Sun is in the sky from their perspective. They’ll tell you it’s still high above the horizon. That tells you that you live on a planet with a curved surface. The Sun can’t be above you and below you at the same time on a flat Earth.

Now ask your friend to measure how high above the horizon; an outstretched fist is about 10 degrees wide. If you know how far away your friend lives, you can apply very simple trigonometry to determine the size of the Earth. (Strictly speaking, that experiment still allows the possibility that Earth is a cylinder. You need to do a second experiment, asking your friend to note the location of Polaris at night, to absolutely determine the spherical shape of the Earth.)

No need to stop there. Physicist and writer Matt Strassler has pointed out that you can even calculate the scale of the solar system for yourself! (Follow the links here for details on how to do it.) Figuring out the relative distances of the planets is surprisingly easy. Finding the absolute distances takes more time and effort, along with detailed observations and a scientific calculator, but you can do it on your own…without a telescope.

The Conspiracy Innoculation

None of these insights will have the slightest impact on a dedicated flat-Earther, mind you. (I know, I’ve tried them.) The pranksters and the argument-junkies have no interest in listening to any information about how the world actually works, needless to say. The true believers will be unswayed as well, because they live in a walled-off reality of their own – one with its own made-up laws of physics and geometry and logic. (I know this firsthand, too.)

Granted, all this analysis might seem like I am making much ado about nothing. The number of sincere flat-Earthers is tiny. Most of the noise on Quora seems to come from just a few dozen hyperactive accounts. Public polling on the issue is notoriously unreliable, but the most credible surveys suggest that about 1-2 percent of the American public claims to actively embrace a flat-Earth faith. Given the statistical uncertainties, that number is nearly indistinguishable from zero.

What makes flat-Earthism notable and worrisome to me is that it is just an extreme version of a far more prevalent conspiracy-theory mindset. Multiple studies have confirmed that people who fall for one type of conspiracy theory are much more likely to believe in others as well. Regardless of the specifics, conspiracy theories tend to operate according to consistent rules. They reject any information that comes from authority figures. More insidiously, they also reject personal investigation that they themselves could perform to discredit the conspiracy.

The essence of the conspiracy mindset is absolute certainty masquerading as open-minded inquiry. Not only do believers reflexively dismiss any evidence that is contrary to the conspiracy, they reject the core concepts of science and logic, except when those concepts (or at least those words) can be invoked in support of the conspiracy. As an experiment, I’ve asked dozens of self-proclaimed flat-Earthers how the Sun rises and sets in a flat-Earth model. Not one answered the question or even accepted the premise of the question! Common responses were that sunset is an optical illusion, a perspective effect, or maybe it does not happen at all.

I could laugh all this off easily if we were talking only about a handful of eccentrics who derive a peculiar pleasure from imagining that they live on a flat planet. But I’ve seen the same mental process at work among anti-vaxxers, QAnon fanatics, 9/11 truthers, and so on. It’s what makes “just asking questions” such a powerful misinformation attack. Anyone who tries to respond in good faith gets clobbered with a Gish gallop of additional questions. Any bystander who wonders, innocently, if there really are valid questions gets drawn into a disorienting miasma of illogic, pseudoscience, falsehoods, and fictions.

This brings me back to my question, Why do I do it? In today’s world, we all put tremendous faith in scientific authority. It’s only natural to have some small, nagging doubts about whether that faith is always well placed. Scientists are only human. All findings contain some uncertainties. Some studies are flawed or irreproducible. Few of us have the time or skills to read those studies themselves; fewer still have the ability to check the results themselves.

But we can, at least, verify some foundational scientific truths about the world. We can do it ourselves, exercising our basic skills in logic and data interpretation. We can spend a very pleasant day and night in nature, observing the beautiful world around us, and ending up with a personal appreciation of the size, shape, and motion of the planet we live on.

Above all, we can embrace the true meaning of that oft-twisted idea, “do your own research.” It does not mean, as it is commonly slurred, “search around online until you find some person or some website that agrees with what you already believed.” It means understanding where knowledge comes from; it means learning how we know what we know. When you know that, you have a powerful inoculation against conspiracy nonsense of all forms.

How’s that for anti-trolling?