# how did flat-earth believers explain the horizon? **URL:** \ **Category:** Factual Questions\ **Created:** [August 20, 2009, 5:18am UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040 "2009-08-20T05:18:34Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![vinniepaz](https://avatars.discourse-cdn.com/v4/letter/v/b4bc9f/32.png) [@vinniepaz](https://boards.straightdope.com/u/vinniepaz)\ **Post date:** [August 20, 2009, 5:18am UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/1 "2009-08-20T05:18:34Z")
That is, at sea. If you believe the Earth is flat, why is there such a clear demarcation between sea and sky, and why is it always the same distance away? ---
**Author:** ![Askance](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/askance/32/8281_2.png) [@Askance](https://boards.straightdope.com/u/Askance)\ **Post date:** [August 20, 2009, 5:26am UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/2 "2009-08-20T05:26:29Z")
> **[Modern flat Earth beliefs](https://en.wikipedia.org/wiki/Flat_Earth_Society#Physics_of_a_Flat_Earth)** > > Anti-scientific beliefs in a flat Earth are promoted by a number of organizations and individuals. The claims of modern flat Earth proponents are not based on scientific knowledge and are contrary to over two millennia of scientific consensus based on multiple confirming lines of evidence that Earth is roughly spherical. Flat Earth beliefs are classified by experts in philosophy and physics as a form of science denial. > Flat Earth groups of the modern era date from the middle of the 20th cent... > [@](#): > > Advocates explain the sinking ship effect by a series of perspective laws, in which a ship on the horizon intersects with the vanishing point, causing it to appear as if it is sinking. The Flat Earth Society holds that there are multiple first-hand accounts of the hulls of ships reappearing after the image is viewed through a telescope or binoculars. ---
**Author:** ![Wendell\_Wagner](https://avatars.discourse-cdn.com/v4/letter/w/8491ac/32.png) [@Wendell\_Wagner](https://boards.straightdope.com/u/Wendell_Wagner)\ **Post date:** [August 20, 2009, 5:34am UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/3 "2009-08-20T05:34:07Z")
Incidentally, you do realize, don’t you, that belief in a flat Earth has been rare ever since the time of the ancient Greeks?: > **[Spherical Earth](https://en.wikipedia.org/wiki/Spherical_Earth)** > > Spherical Earth or Earth's curvature refers to the approximation of figure of the Earth as a sphere. > The earliest documented mention of the concept dates from around the 5th century BC, when it appears in the writings of Greek philosophers. In the 3rd century BC, Hellenistic astronomy established the roughly spherical shape of Earth as a physical fact and calculated the Earth's circumference. This knowledge was gradually adopted throughout the Old World during Late Antiquity and the Middle The... ---
**Author:** ![Freddy\_the\_Pig](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@Freddy\_the\_Pig](https://boards.straightdope.com/u/Freddy_the_Pig)\ **Post date:** [August 20, 2009, 1:32pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/4 "2009-08-20T13:32:12Z")
> [@vinniepaz](#): > > That is, at sea. If you believe the Earth is flat, why is there such a clear demarcation between sea and sky, and why is it always the same distance away? I don’t understand the question. The difference in the appearance of sea and sky on an infinite flat-earth and our very large round-earth is barely noticeable. Hull-first disappearance is only visible with tall ships and very clear and calm days, and can easily be missed by casual observation. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [August 20, 2009, 3:04pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/5 "2009-08-20T15:04:03Z")
> [@](#): > > Incidentally, you do realize, don’t you, that belief in a flat Earth has been rare ever since the time of the ancient Greeks?: But certainly not non-existent And Cyrus Teed may not have believed in a Flat Earth, but his beliefs still would’ve ruled out a horizon: > **[Cyrus Teed](https://en.wikipedia.org/wiki/Cyrus_Teed)** > > Cyrus Reed Teed (October 18, 1839 – December 22, 1908) was a U.S. eclectic physician and alchemist turned pseudoscientific religious leader and self-proclaimed messiah. In 1869, claiming divine inspiration, Teed took on the name Koresh and proposed a new set of scientific and religious ideas which he called Koreshanity, including the belief in the existence of a concave, or "cellular", Hollow Earth cosmology positing that the sky, humanity, and the surface of the Earth exist on the inside of a un... ---
**Author:** ![Wendell\_Wagner](https://avatars.discourse-cdn.com/v4/letter/w/8491ac/32.png) [@Wendell\_Wagner](https://boards.straightdope.com/u/Wendell_Wagner)\ **Post date:** [August 20, 2009, 3:06pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/6 "2009-08-20T15:06:00Z")
True, but it was mostly believed by people who weren’t interested in things like rational argument anyway. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [August 20, 2009, 3:06pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/7 "2009-08-20T15:06:55Z")
> **[Modern flat Earth beliefs](https://en.wikipedia.org/wiki/Flat_Earth_Society)** > > Modern flat Earth beliefs are promoted by organizations and individuals advocating that the Earth is flat while denying the Earth's sphericity, contrary to over two millennia of scientific consensus. Flat Earth beliefs are pseudoscience; the hypotheses and assertions are not based on scientific knowledge. Flat Earth advocates are classified by experts in philosophy and physics as science deniers. > Flat Earth groups of the modern era date from the middle of the 20th century; some adherents are... ---
**Author:** ![Elendil\_s\_Heir](https://avatars.discourse-cdn.com/v4/letter/e/7cd45c/32.png) [@Elendil\_s\_Heir](https://boards.straightdope.com/u/Elendil_s_Heir)\ **Post date:** [August 20, 2009, 3:09pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/8 "2009-08-20T15:09:13Z")
Lyndon Johnson liked to tell the story about a young, impoverished teacher, desperate for work during the Great Depression, who was interviewed for a job by a rural Texas school board. The interview went well until one board member drawled, “We have some people around here who believe that the Earth is flat, and some who believe it’s round. What do you think?” The teacher eagerly said, “I can teach it either way!” ---
**Author:** ![HorseloverFat](https://avatars.discourse-cdn.com/v4/letter/h/8e8cbc/32.png) [@HorseloverFat](https://boards.straightdope.com/u/HorseloverFat)\ **Post date:** [August 20, 2009, 3:18pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/9 "2009-08-20T15:18:56Z")
The flat earth society is like discordianism: its a satirical group. There’s no real flat earth thesis since about 500bc or so is when the spherical earth was a given. So youre asking if we have any documentation of someone from before 500bc was engaged into a rational debate about the horizon? Err, I doubt it. On top of it, the flat earth believed in ancient times was like an island on an infinite sea. Im sure if you asked an 800bc person about this the answer would involve things like turtles holding up the earth or magic wizards and unicorns. Youre not getting a rational answer. ---
**Author:** ![vinniepaz](https://avatars.discourse-cdn.com/v4/letter/v/b4bc9f/32.png) [@vinniepaz](https://boards.straightdope.com/u/vinniepaz)\ **Post date:** [August 20, 2009, 3:46pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/10 "2009-08-20T15:46:39Z")
> [@HorseloverFat](#): > > The flat earth society is like discordianism: its a satirical group. There’s no real flat earth thesis since about 500bc or so is when the spherical earth was a given. So youre asking if we have any documentation of someone from before 500bc was engaged into a rational debate about the horizon? Err, I doubt it. > > On top of it, the flat earth believed in ancient times was like an island on an infinite sea. Im sure if you asked an 800bc person about this the answer would involve things like turtles holding up the earth or magic wizards and unicorns. Youre not getting a rational answer. Thanks, this makes sense. 500 bc is quite a lot longer ago than I was taught in elementary school, but it certainly isn’t the first time. ---
**Author:** ![DrFidelius](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/drfidelius/32/3447_2.png) [@DrFidelius](https://boards.straightdope.com/u/DrFidelius)\ **Post date:** [August 20, 2009, 3:50pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/11 "2009-08-20T15:50:59Z")
> [@vinniepaz](#): > > That is, at sea. If you believe the Earth is flat, why is there such a clear demarcation between sea and sky, and why is it always the same distance away? The demarkation line is where the vault of the sky meets the ground. It alwas looks the same distance away because the distance you can travel in a lifetime is very small compared to the distance it is from us, although i am sure it is more noticable to those peoples who live nearer to the edge than we do. The clearly observed fact that we live at or close to the center is a sign of our being favourites of the gods, not like those frog-faced heathens over there… ---
**Author:** ![dracoi](https://avatars.discourse-cdn.com/v4/letter/d/90db22/32.png) [@dracoi](https://boards.straightdope.com/u/dracoi)\ **Post date:** [August 20, 2009, 4:01pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/12 "2009-08-20T16:01:30Z")
> [@vinniepaz](#): > > Thanks, this makes sense. 500 bc is quite a lot longer ago than I was taught in elementary school, but it certainly isn’t the first time. Most people are taught that Columbus proved the world was round and that the resistance to his voyage was due to belief in a flat Earth. In fact, the resistance was a dispute over how big the Earth was. Ironically, the authorities of the day not only believed in a round Earth, but they had the right size. They knew Asia was way the hell too far away. Columbus was entirely wrong; he thought the world was much smaller. When he got lucky and found something else, he insisted it was Asia (despite any real evidence for that). ---
**Author:** ![aldiboronti](https://avatars.discourse-cdn.com/v4/letter/a/9fc348/32.png) [@aldiboronti](https://boards.straightdope.com/u/aldiboronti)\ **Post date:** [August 20, 2009, 4:06pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/13 "2009-08-20T16:06:31Z")
> [@HorseloverFat](#): > > The flat earth society is like discordianism: its a satirical group. There’s no real flat earth thesis since about 500bc or so is when the spherical earth was a given. So youre asking if we have any documentation of someone from before 500bc was engaged into a rational debate about the horizon? Err, I doubt it. > > On top of it, the flat earth believed in ancient times was like an island on an infinite sea. Im sure if you asked an 800bc person about this the answer would involve things like turtles holding up the earth or magic wizards and unicorns. Youre not getting a rational answer. Have you read the posts on the [Flat Earth Forum](http://www.theflatearthsociety.org/forum/)? It doesn’t look satirical to me. There is no position, however absurd or outdated, which will not have true believers somewhere. ---
**Author:** ![HorseloverFat](https://avatars.discourse-cdn.com/v4/letter/h/8e8cbc/32.png) [@HorseloverFat](https://boards.straightdope.com/u/HorseloverFat)\ **Post date:** [August 20, 2009, 4:25pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/14 "2009-08-20T16:25:59Z")
\>Have you read the posts on the Flat Earth Forum? It doesn’t look satirical to me. Sounds like you’re bumping up against Poe’s Law: [http://tvtropes.org/pmwiki/pmwiki.php/Main/ptitlehkm94ato?from=Main.PoesLaw](http://tvtropes.org/pmwiki/pmwiki.php/Main/ptitlehkm94ato?from=Main.PoesLaw) ---
**Author:** ![aldiboronti](https://avatars.discourse-cdn.com/v4/letter/a/9fc348/32.png) [@aldiboronti](https://boards.straightdope.com/u/aldiboronti)\ **Post date:** [August 20, 2009, 4:57pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/15 "2009-08-20T16:57:32Z")
> [@HorseloverFat](#): > > \>Have you read the posts on the Flat Earth Forum? It doesn’t look satirical to me. > > Sounds like you’re bumping up against Poe’s Law: > [http://tvtropes.org/pmwiki/pmwiki.php/Main/ptitlehkm94ato?from=Main.PoesLaw](http://tvtropes.org/pmwiki/pmwiki.php/Main/ptitlehkm94ato?from=Main.PoesLaw) From the Flat Earth [FAQ](http://theflatearthsociety.org/forum/index.php?topic=11211.0) > [@](#): > > Q: “Is this site for real?” > > A: This site is real. There are members who seriously believe the Earth is flat. However, there are also members who do not. I’ve been browsing the forum. Some of these guys are definitely for real. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [August 20, 2009, 8:08pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/16 "2009-08-20T20:08:01Z")
I was taught that Columbus proposed a round earth and met resistance, having difficulty getting his explorations supported for this reason, similar to what dracoi says. It’s funny, though, that paintings from around his time sometimes show mariners holding octants (an earlier form of sextant) that would not have any function if the world were flat. And, though I kept getting shot down for this before, I still offer the observation that I can’t for the life of me tell the Earth is a sphere by looking at the horizon, boats or not. Things further away on the ocean keep looking smaller, but I can’t see their lower portions disappear, not even in binoculars. What I see is things getting dimmer and hazier and smaller, and various subtle horizontal (meaning orthagonal to vertical) features at different altitudes (meaning angle from said horizontal). It isn’t even obvious what element of the image I see IS the horizon. Even from a jet at 55,000 feet I don’t see a curve - and this is no surprise, as I’m only a quarter percent further from the center of the earth than sea level. Not that I’m calling anybody here a liar, but I think most people are too easily dismissive of this old misunderstanding. No Greek would have had to measure shadows in a well to figure out that the Earth is a sphere if you could see it! ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [August 20, 2009, 8:16pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/17 "2009-08-20T20:16:25Z")
> [@Napier](#): > > Not that I’m calling anybody here a liar, but I think most people are too easily dismissive of this old misunderstanding. No Greek would have had to measure shadows in a well to figure out that the Earth is a sphere if you could see it! You can see it next time there is a lunar eclipse. And the ancient Greeks knew how those worked. (Well, except for the whole heliocentricity thing, but that’s largely irrelevant.) ---
**Author:** ![HorseloverFat](https://avatars.discourse-cdn.com/v4/letter/h/8e8cbc/32.png) [@HorseloverFat](https://boards.straightdope.com/u/HorseloverFat)\ **Post date:** [August 20, 2009, 8:16pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/18 "2009-08-20T20:16:42Z")
The earth is obviously round, the greeks realized this by looking at the shadow it casts on the moon. Stars rise and fall, so it cant be too flat of a disc. Now is it like a quarter or is it like a baseball? Considering you can see the curvature on a flat plain its most likely like a sphere. Ancient Indians and Arabs came to the same conclusions. So yes, its pretty trivial for an ancient astronomer to figure this stuff out. From wikipedia: Washington Irving’s 1828 biography of Columbus popularized the idea that Columbus had difficulty obtaining support for his plan because Europeans thought the Earth was flat.[8] In fact, the primitive maritime navigation of the time relied on the stars and the curvature of the spherical Earth. The knowledge that the Earth was spherical was widespread, and the means of calculating its diameter using an astrolabe was known to both scholars and navigators.[9] A spherical Earth had been the general opinion of Ancient Greek science, and this view continued through the Middle Ages (for example, Bede mentions it in The Reckoning of Time). In fact Eratosthenes had measured the diameter of the Earth with good precision in the second century BC.[10] Where Columbus did differ from the generally accepted view of his time is his (incorrect) arguments that assumed a significantly smaller diameter for the Earth, claiming that Asia could be easily reached by sailing west across the Atlantic. Most scholars accepted Ptolemy’s correct assessment that the terrestrial landmass (for Europeans of the time, comprising Eurasia and Africa) occupied 180 degrees of the terrestrial sphere, and dismissed Columbus’s claim that the Earth was much smaller, and that Asia was only a few thousand nautical miles to the west of Europe. Columbus’s error was put down to his lack of experience in navigation at sea.[11] ---
**Author:** ![njtt](https://avatars.discourse-cdn.com/v4/letter/n/ecd19e/32.png) [@njtt](https://boards.straightdope.com/u/njtt)\ **Post date:** [August 20, 2009, 8:17pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/19 "2009-08-20T20:17:46Z")
Parmenides realized that the Earth was round when he saw its shadow on the moon during a lunar eclipse. [Mind you, he did not think it happened really. He did not thing _anything ever_ happened really. And he thought _everything_, which was the only thing that really existed, was round. Strange man.] ---
**Author:** ![Freddy\_the\_Pig](https://avatars.discourse-cdn.com/v4/letter/f/a587f6/32.png) [@Freddy\_the\_Pig](https://boards.straightdope.com/u/Freddy_the_Pig)\ **Post date:** [August 20, 2009, 8:29pm UTC](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040/20 "2009-08-20T20:29:46Z")
> [@HorseloverFat](#): > > Considering you can see the curvature on a flat plain its most likely like a sphere. Absolute hogwash. The horizon would be round even on an infinite flat earth. [Next page](https://boards.straightdope.com/t/how-did-flat-earth-believers-explain-the-horizon/507040.md?page=2)