Any reasonable person knows that I have already proved this many times over.  You are going to keep claiming "but that's not proof" no matter what I say and those who are open to reason already know.  The Ptolemaic model (which includes a spherical earth) was the consensus view of Catholics from around 700 to 1800.  This position existed before then (including among Church Fathers) but alongside other views.

I have not noticed any difference in the amount of emotionally charged language used by the two sides of this issue.  Few people of any position discusses it calmly and rationally.  So this characeristic does not seem like something that will be any help in determining which side is correct.

I have noticed that lately you only seem to point out illogical or otherwise flawed posts when they support the globe earth position.  This suggests that, rather than objectively seeking out the more logical position, you have emotionally chosen a position and are guilty of confirmation bias.

Virtually every claim you have made in regard to history and theology supporting flat earth has been incorrect and has been conclusively shown to be incorrect with copious amounts of credible references.  You dismiss all this evidence on the flimsiest of excuses or ignore it altogether and continue to make the same false claims.

I am not going to waste my time posting the same overwhelming evidence over and over again, but it has all been presented on this forum.  You are wrong and have been proven to be wrong.  You do not have a "cohesive and well-founded argument" and this is obvious to any objective observer.

Science is not an area in which I feel qualified to evaluate your statements, but you have so completely destroyed your credibility by your egregious errors in areas in which I am knowledgeable that I find it unlikely that you know what you are talking about in that area either.

We're not talking about vanishing point.  I've seen demonstrations of how a visual convergence happens between the plane and the object well before it reaches its vanishing point.

An article like this I give little credibility to because it's emotionally charged, repeatedly referring to flat earth "deception", "deception techniques", attempting to win over "the gullible into their cult".

I've seen pictures where JUST THE BOTTOM of the ship disappears, i.e. it's not reached its vanishing point, and then when you zoom in you can see the entire ship again, including the bottom.  So the fact that this article makes it about "vanishing point" ... well, it's creating a false straw man argument.  Consequently, it's the author of this article who's guilty of deception.

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Since no one has managed to respond to the OP after 3 pages (while pretending to have responded) I'll post it again, with more material:
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Anybody who gives the flat earth idea the slightest amount of critical examination will realize that it's complete balderdash.  
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Saying that 6 miles at sea should account for 24 feet of drop is nonsense: a sight line 6 feet above the water would meet the top of another 6-foot pole at 6 miles' distance if the earth were "flat."
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Here is a video of a large ship quite clearly going over and behind the curvature of the sea:
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The meme-like caption in the title frame shown asks you to consider this:
IF the earth were "flat" the top of the container ship being magnified here with a telephoto lens located above the water's "flat" surface would certainly be higher than the top of the smaller boat located part way in between the camera and the container ship.
While this discrepancy does not "prove" anything, it most certainly does not support the claim that the water surface is "flat" because the VERY TALL container ship superstructure is well BELOW the top of the much shorter boat.
Furthermore, we can see the small boat's hull entirely but the ship's hull is completely out of sight below the water's surface, where no amount of magnification can bring it into view, only ascending to higher ground for a viewpoint of higher elevation will enable the camera to see the ship's hull.
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The ship does not become more visible in its parts when the telephoto zooms in for a magnified view.
The hull disappears without question behind the water surface in the foreground, that is, the surface on which smaller boats traverse right there for you to see. You can see the hull of the smaller boat but not the hull of the container ship.
As it goes along gradually the containers on deck disappear as well below the water surface as if the ship were sinking.
Nobody can make the containers and the hull re-appear by zooming in through a telephoto lens.
One thing that is NOT shown in this one-position video is what this ship looks like from a higher vantage point, like from a nearby bluff.
There are other videos that show that, but flat-earthers are terrified of them so they refuse to acknowledge them, or, at best, accuse them of being fake.
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The container ship starts quite visible with most of its hull in view, but sailing away for an hour appears to sink gradually into the sea.
Eventually the containers on deck and the ship's superstructure are all hidden behind the apparently rising water level of the sea.
The smaller boats in between the container ship and camera are not rising and falling over huge waves, so the swells are quite small, about 2 feet.
Can you refute this simple evidence?
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The website page below compares views of Polaris from various latitudes on a "flat" earth vs. a spherodial earth.
The angle of sight from earth to Polaris is identical to the viewer's latitude on earth!
All viewers are seeing the sun at the same time, so the sun must be located in the same place, consequently all viewers must be looking in the same direction to see the sun there.
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I find it quite telling that nobody has seen fit to comment on this concept.
If you measure the angle from the horizon to Polaris it's always the same as the latitude where you're standing.
Sailors at sea have been using this trick for hundreds of years.
That's how anyone can know their latitude with one simple measurement, that is, so long as they can see Polaris.
Furthermore, it makes no difference what time of night it is, Polaris is always in the same place in the sky.
The further north you are the higher it gets until at the north pole it's directly overhead.
And in the southern hemisphere, the same feature (but no star) exists where the star tracks circle and you can measure your latitude south of the equator with the same technique.
So how does the "flat" earth map explain this?
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This is a very powerful indicator that a "flat" earth concept is useless, since as the diagram shows, observers in various latitudes have to look in different directions to see the same thing.
Furthermore, viewers south of the equator can't see Polaris at all.
There have been some flat-earthers who have tried to be clever or something by claiming that people up to 20 degrees south of the equator can see Polaris, but they haven't managed to provide any evidence of that. When I replied, "They must have been at the ridge line of the Andes Mountains" nobody responded. I wasn't supposed to know their secret!
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Does this support flat-earthism or is it rather supportive of a spheroidial earth?
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http://i.imgur.com/CPU63Tm.jpg

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Another highly problematic reality for flat-earthers :
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How can we measure the relative distance of the earth-to-moon vs. earth-to-sun?
You don't need any fancy equipment for this.
Just a rectangular block of white styrofoam or a pizza box (after you've eaten the pizza!) will work just fine.
Or, you can eat the pizza WHILE you take the measurements. I did that and it was great. Very pleasant afternoon!
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Can you refute this evidence that the sun is much further away from earth than the moon is?  
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https://www.youtube.com/watch?v=lVgx0Eio2Mg
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An excellent response to flat earth nonsense.
Numbers and simple math disproves all their childish yammering.
The childish agnosticism of Ladislaus notwithstanding.
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Another H-U-G-E problem for flat-earthers:
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It's painfully obvious that the sun doesn't twirl around above the earth the way flat-earthers claim.
How would Antarctica get 24 hour sun if it did?
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https://vimeo.com/136977957

And no, Polaris has not always been the Pole star in the past, nor will it be in the future.
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Essentially, belief in the silly idea the earth is "flat" relies entirely on ignorance.
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For at least some, their ignorance is willful and impudent, therefore quite repulsive.
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Below is the basis for the argument. Seems pretty sound to me. Don't be troubled. Explain how this is mischaracterizing the optical phenomenon. Again, I don't care too much but let me know how I'm being duped by this article. Don't really want to argue. Unlike my enemies in this subforum, I'm not dogmatic about this so I'm not using too much brain power on it.


The Vanishing Point
The vanishing point of an object is when the object is so far away from you it seems to disappear. Objects will disappear at different distances from you depending upon their size, your vision, and potentially atmospheric conditions. But the smaller the object, the closer to you it will reach it's vanishing point, and the contrary is true as well; the larger an object, the further away from you it will seem to vanish.

Versus over the Horizon
...When you get a large object, such as the container ship in the video below, you'll see that part or all of the ship is obscured by the horizon before it reaches it's vanishing point. The portion obscured by the horizon, it can be easily seen, cannot be zoomed back in with the zoom lens, and the rest of the boat is obviously visible, so it is clearly not an issue of the bottom being too small to see. It's simply obscured by the curvature of the earth!
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In this case, many have realized that these objects simply cannot be brought back with a telescope, so they now claim that objects disappearing by 'perspective' just disappear bottom first, when it's clear to anyone who has watched small objects disappear into the distance, like these batteries on colored paper prove, this is simply not true. We can still see the furthest away colored paper on the floor, just as we'd expect to see.

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Your emotionally charged outbursts discredit everything you say, Ladislaus.