[Pete Svarrior]

I think you're being a bit pedantic about the word sharp. OK, the horizon might not be 100% sharp but can we agree that there's a pretty obvious difference between these two images

We agree that there is a clear difference between the two images. However, the counterargument is not "pedantic" - you are asserting, as fact, something that would be impossible on RET, and which does not occur in reality. When it turns out that you're patently wrong, you dismiss it as obviously joking pedantry.

But the point is according to the RE model you're looking at the edge of something.

This is strictly incorrect. That's the whole issue.

But what is stopping you seeing further?

Waves, usually. A physical obstruction produces the boundaries which you describe as a "sharp horizon" (which is neither sharp, nor is it the true horizon). Less often, in particularly good conditions, atmospheric conditions result in a very blurry vanishing point - this is much closer to the true horizon.

I'd suggest the method of starting with a hypothesis and devising an experiment to test it has served humanity pretty well.

Yes - if you change what I said to make no sense, you'll find it easy to respond to. You'll also find that your response will be extremely unconvincing to most people. So, for those at the back of the room:

Your problem is that you're not testing hypotheses - that would be science, which may be a slightly flawed prototype of Zeteticism, but it's largely servicable. What you're doing is deciding your conclusion and then tilting at windmills until you find something that you think confirms it.

[AATW]

However, the counterargument is not "pedantic" - you are asserting, as fact, something that would be impossible on RET, and which does not occur in reality.

Are you claiming that this does not show a clear, sharp horizon line?



I'd suggest the line between sea and sky is pretty clear. As for sharp, it's certainly not a gradual fade between sea and sky like in the foggy day image.

This is strictly incorrect. That's the whole issue.

I'm not sure what you mean by this. I was being a little poetic, but if the earth is a globe then the horizon is simply a line along its surface, isn't that an edge?
What would you call it?

Waves, usually. A physical obstruction produces the boundaries which you describe as a "sharp horizon"

I would claim that the picture above shows a sharp horizon. There's a clear line between the sea and sky.
I took that photo, and I did so when going down a hill on my way to the beach. Point being, I was reasonably high up, way above the level of any waves.
If you're looking down on the waves then you're looking over the top of them. That means on a flat plane the waves can't be blocking the sea further away than them.
Another diagram I did when I was explaining why waves can't produce the sinking ship effect IF your viewer height is higher than the waves:



As you're looking downwards over the top of the waves you'll always have a clear line of sight to the sea even if the sea continues perfectly flat after that last wave rather than stopping at the building. Your hypothesis could makes sense if you're very close to sea level and there are waves higher than your viewer height. Once you're up a few meters I don't see how that would work.

Less often, in particularly good conditions, atmospheric conditions result in a very blurry vanishing point - this is much closer to the true horizon.

I'm interested by what you mean by vanishing point and true horizon. The first is a theoretical thing. I mean, obviously there are limits of optical resolution but that doesn't apply when there are thousands of miles of sea. And because of refraction there's a difference between geometric horizon and the apparent horizon. I'm not clear what you mean by the "true" horizon.

Your problem is that you're not testing hypotheses - that would be science, which may be a slightly flawed prototype of Zeteticism, but it's largely servicable. What you're doing is deciding your conclusion and then tilting at windmills until you find something that you think confirms it.

I'm claiming that these observations:
1) A sharp horizon line on a clear day
2) The distance to the horizon and angle of dip to the horizon increasing with altitude.
Can be explained well on a globe earth. I'm not suggesting they're the only explanations, but unless these observations are in dispute they need some FE explanation.
You seem to dispute the first of those observations. I don't know how to resolve that.

And, again, in Zeteticism you say you "devise an experiment that will determine the shape of the Earth". What's the experiment?
I mean, there's the Bedford Level Experiment I guess, but the results of that are hotly disputed and it makes assumptions about how light moves.
Any experiment relies on certain assumptions of course, but that means the results are only as good as those assumptions.

[Pete Svarrior]

Are you claiming that this does not show a clear, sharp horizon line?

Of course. If I was claiming otherwise, we could rule RET out straight away.

the horizon is simply a line along its surface

This continues to be strictly incorrect.

isn't that an edge?

No.

What would you call it?

I wouldn't rename the horizon - we generally name things for a reason. It helps facilitate meaningful conversation, and avoids silly blunders like your "sharp horizon".

I would claim that the picture above shows a sharp horizon

Yes, this continues to be the problem with your argument.

I was explaining why waves can't produce the sinking ship effect

We are not currently talking about the Sinking Ship Effect. We're talking about your attempts at redefining the horizon under RET.

I'm interested by what you mean by vanishing point and true horizon. The first is a theoretical thing.

I am saddened to hear that things you have personally witnessed and photographed are "theoretical" to you. I won't waste time on that, since you're "obviously joking".

I'm not clear what you mean by the "true" horizon.

Have you considered Googling it? It's three sentences deep on the Wikipedia page for "Horizon". It would be a good idea to understand the basic concepts you're trying to discuss before you declare all of RET to be incorrect.

I'm claiming that these observations:
1) A sharp horizon line on a clear day

An impossibility which you repeatedly illustrated not happening.

2) The distance to the horizon and angle of dip to the horizon increasing with altitude.

Which never approaches the distance of the true horizon...

Can be explained well on a globe earth.

They can't be explained well on a globe Earth. In fact, they directly contradict RET. This would be groundbreaking stuff, except you haven't made these observations - you simply claimed them while presenting evidence to the opposite.

I'm not suggesting they're the only explanations, but unless these observations are in dispute they need some FE explanation.

They are in dispute - with your own evidence.

You seem to dispute the first of those observations. I don't know how to resolve that.

Well, you could stick to observable facts. Alternatively, I can start demanding that you explain why the air is upside-down on RET. After all, this nEeDs some explanation.

And, again, in Zeteticism you say you "devise an experiment that will determine the shape of the Earth". What's the experiment?
I mean, there's the Bedford Level Experiment I guess, but the results of that are hotly disputed and it makes assumptions about how light moves.
Any experiment relies on certain assumptions of course, but that means the results are only as good as those assumptions.

What the fuck are you talking about, AATW? The problem with your approach is not that you start with assumptions. The problem is that you presuppose (not assume) the outcome, and that you tailor your reasoning to reach that presupposed outcome.

[SteelyBob]

Are you claiming that this does not show a clear, sharp horizon line?

Of course.

Well, then everything else that follows is rather irrelevant, isn't it? In what way is that not a clear, sharp horizon? And if you were claiming otherwise...ie you were claiming it did show a clear line, how would that 'rule out RET'?

[Pete Svarrior]

Well, then everything else that follows is rather irrelevant, isn't it?

Indeed. You won't be able to defend RET by blundering middle-school-level knowledge. If you could catch up and get back on track, we can abandon this "sharp horizon" nonsense and maybe start discussing something relevant.

In what way is that not a clear, sharp horizon?

I don't understand the question. It's not sharp or clear "in the way" that it is blurry and gradual. This is not a complex statement, so there's not much to elaborate on.

And if you were claiming otherwise...ie you were claiming it did show a clear line, how would that 'rule out RET'?

Basic optics and geometry. If you were to observe a sharp, true horizon, this would necessitate several factors:

• The atmolayer would have to be effectively absent.
• The Earth would have to have an edge.

These factors do not hold under RET, so if you were able to observe a sharp horizon, you would disprove RET. Proof by contradiction.

Which, of course, is a moot point, because you will never observe a sharp horizon, nor will you ever observe the true horizon under either model.

I'm think I'm starting to understand y'all's objections to science and Zeteticism. It would be pretty hard to methodically inquire into the world around you if you got stumped by every little fact. GUH-WHAAAA? What is this true horizon of which you speak?! Oh my goodness, what ever is the difference between a gradient and a sharp border?! HUUUH?! But this looks sooooo sharp to my naked eye when viewed on a tiny screen.

[secretagent10]

Indeed. You won't be able to defend RET by blundering middle-school-level knowledge. If you could catch up and get back on track, we can abandon this "sharp horizon" nonsense and maybe start discussing something relevant.

Well, it is essentially sharp. You’re disagreeing on what you’re calling sharp. RE (and, I supposed, FE) doesn’t suggest a mathematically perfect divide between ocean and sky for various reasons. I would look at that picture and call it sharp horizon and agree it is “sharp” by the same reasoning that a knife is sharp. Yes, it is sharp - but if I look at it under a microscope I could call it a dull edge.
Just feels like straying from the premise.

[Pete Svarrior]

Well, it is essentially sharp. You’re disagreeing on what you’re calling sharp. RE (and, I supposed, FE) doesn’t suggest a mathematically perfect divide between ocean and sky for various reasons. I would look at that picture and call it sharp horizon and agree it is “sharp” by the same reasoning that a knife is sharp. Yes, it is sharp - but if I look at it under a microscope I could call it a dull edge.
Just feels like straying from the premise.

Right. Yeah, that's roughly the level of hand-waving I was expecting here. "Well, y'know, it isn't sharp, but it's sharp."

Words have meanings for a reason. In this case, the dispute at hand is whether there is a gradient to the horizon. AATW claims, in no uncertain terms (despite your attempt at muddying the subject) that the absence of one would disprove FET. He backs this up with diagrams, which clearly show that, in his view, the horizon in RET would be a mathematically perfect divide. His side-view illustrates a point intersection.



He is correct - this would disprove FET. What he misses is that the absence of one would also disprove RET, and reality itself. This is not the time to say "Well, okay, but what if we make the word mean something else? Something less restrictive, maybe?".

Now, you are also correct, in the most useless way possible - these claims are ludicrous as currently presented. That's exactly my contention. Of course, if you examine the photographs, you'll arrive at some "eh-maybe-sharp-ish-but-not-actually-sharp" conclusion. You chose the words "essentially sharp". But the moment you accept that anti-definition, you lose your comparative argument. The horizon is "uhhh-kinda-sorta-sharp-but-not-really" in both models. So you're left with two options: doubling down on the horizon actually being sharp and posting photos of it not being so, or realising that there isn't anything here that would distinguish FE from RE. You'll be hard-pressed to find a third option that's internally consistent.

Finally, the question isn't what "RE" suggests - we are humans having a conversation, not nebulous concepts in a philosophical vacuum. AATW is not an orthodox RE'er, and he regularly disagrees with RE doctrine. He usually doesn't realise when he's doing it, but that's pretty normal when you accept a self-contradictory worldview.

[Gonzo]

Do you live within reach of the coast, Pete?

[SimonC]

So the distinct line you see is the beginning, the top, or the falling away of the curve? Do you not consider that if the earth was a continuous curve there would be no distinct line? Curves dont have distinct lines. Even curves 'fade away'. And if there was a distinct line it would be a different (further or nearer line) for every person of differing heights and stood on different heights above sea level. You cant have an infinite number of 'distinct lines'.

Of course curves have a distinct line.  Look at a snooker/pool ball; it curves away to the "horizon", which is a distinct line.  Sit in your car and look over the hood.  Distinct line. 

And of course there are an infinite number of distinct lines, that's the point.  The visible horizon is unique to the observer.  If I am standing 1 metre behind you on a boat, your horizon is one metre further away than mine.

Exactly - these are almost imaginary lines they are not physical ones that are there all the time - they are ther when we appear a certain distance and angle from them.

[SimonC]

So the distinct line you see is the beginning, the top, or the falling away of the curve? Do you not consider that if the earth was a continuous curve there would be no distinct line? Curves dont have distinct lines. Even curves 'fade away'.

What are you talking about? "Curves don't have distinct lines" is a meaningless sentence. And in what sense do curves "fade away"?
Look at any spherical object. You can see the edge of it, can't you? A clear line. The edge isn't all fuzzy. I happen to have a globe in the house so I took this photo:



Is that a clear enough line for you? And if you zoom in to a portion of this image then even at this scale the horizon starts to flatten out:



That's what the horizon is. Why would that happen on a FE? What presents you seeing further than the distinct horizon on a FE? It isn't visibility, you can see distant landmasses beyond the horizon, you just can't see the bottom of them. The only exception to that is on a foggy day when visibility is poor, in that case you don't see a clear horizon line, the sea just fades out. But what would cause the clear horizon line on a FE? What is hiding the rest of the sea?

And if there was a distinct line it would be a different (further or nearer line) for every person of differing heights and stood on different heights above sea level.

Correct. Which is exactly what we observe. The higher you ascend the further you can see. You ever looked out a airplane window? You can see a horizon much further away than when you're on the beach. I took these photos with the same globe as above, raising the camera to simulate going up in altitude.



Note how the label "Russia" can be clearly seen in the bottom of the 3 photos but is hidden behind the curve in the top photo from a "lower" altitude.
Note out the word "Mountains" (upside down) is further from the horizon as you ascend.

You cant have an infinite number of 'distinct lines'.

The distinct line isn't a physical thing, it's simply the limit of how far you can see on the globe earth, and the reason for it is the earth curves away from you. That's why the distance to the horizon increases with altitude, because you can see further over the curve. This diagram illustrates the principle:

Sorry to spoil the show but they look fuzzy to me. As for the one that looks like its been created with a thick black highlighter well...
And as for these lines. Are they a given depth/size? If there's a definite physical line it must have some dimensions to represent its 'boldness' for example.
The fact they look fuzzy as they obviously do to most people suggests that there's more beyond them. Only the bias of a global earth theorist will see a solid back line that could even represent a 'boom' across the horizon.

[SimonC]

So the distinct line you see is the beginning, the top, or the falling away of the curve? Do you not consider that if the earth was a continuous curve there would be no distinct line? Curves dont have distinct lines. Even curves 'fade away'. And if there was a distinct line it would be a different (further or nearer line) for every person of differing heights and stood on different heights above sea level. You cant have an infinite number of 'distinct lines'.

As the others have said, the line you see is merely the tangent of your sight line and the globe. Yes, that does mean that the horizon appears in a different place for different observer heights. If the distance to the horizon is less than the meteorological visibility, then you will see a distinct horizon line. If it’s not, then you won’t see one - it will be blurry or completely indistinct, which is what you would see every day on a flat earth. The fact that you don’t see this should be a major clue that the earth isn’t flat.

And moving on to your second point if you know of such a person who lay in a boat staring towards the sky at every single star for 24 non-stop hours and mentally noting their continuous shift in positions exactly then I should like to meet this person. And you say that this gives an indication that the surface we are on is rotating - had you not given any consideration to the fact that it could be the stars that are rotating and not the earth?

Well, you don’t need to do this - simple photography lets you do it very clearly, or you can just note the azimuth and elevation of a few obvious stars and see the pattern. Either way, they rotate in a neat circular pattern, every 24 hours.

So then you might reasonably ask ‘couldn’t the stars be moving around the earth?’ - a perfectly valid line of enquiry. But there are several ways we know this is not the case:

- if the stars are rotating around the earth, why does the neutral point at the centre of rotation vary linearly with our latitude, and why do the stars disappear below the horizon during part of the their rotation? If I’m in Scotland and you’re in Africa, why can I see stars that are below the horizon for you? The wiki invoked ‘bendy light’ at this point. Aside from being an incomplete explanation, if it were the case that light was bending in the vertical plane, as asserted, then the neat circular pattern that we observe would not happen, as the paths would be distorted by the EA.

- why the exact 24 hour period of rotation, precisely the same as the apparent periodicity of the sun, when the sun is clearly ‘moving’ in a different manner and at a closer range than the stars?

A rotating spherical earth explains all of these things perfectly. We can even measure the rotation using gyroscopes, both mechanical and laser. It all lines up.

If you have ever seen a time lapse photo of the stars with the resultant image showing them as if they are circling the earth then that would suggest they are moving and not the earth otherwise they would not look like complete circles as the earth would be turning away or toward then not circling beneath them. The only way to replicate that effect is at one of the poles.

[AATW]

Right. Yeah, that's roughly the level of hand-waving I was expecting here. "Well, y'know, it isn't sharp, but it's sharp."

As secretagent says, when someone says a knife is sharp no-one is going to get an electron microscope out, note the bumps at that level and say "well akchooalley...".
Put any of the pictures I've posted through an edge detection algorithm and it's going to show you a clear horizon line unless you make it so sensitive then it literally only detects a line if the two adjacent pixels are completely different. Compare and contrast with the foggy day image where you're not going to get an edge. You've already conceded there's a difference and that's the point I have been making.

AATW claims, in no uncertain terms (despite your attempt at muddying the subject) that the absence of one would disprove FET. He backs this up with diagrams, which clearly show that, in his view, the horizon in RET would be a mathematically perfect divide. His side-view illustrates a point intersection.

This is all accurate. But I do also recognise that we live in reality, not a mathematically perfect world. My diagram shows the situation, but of course in reality the sea isn't perfectly flat, there are some atmospheric effects. I'm using the word sharp to contrast the horizon on a clear day with a foggy day where the sea just fades out.

He is correct - this would disprove FET. What he misses is that the absence of one would also disprove RET, and reality itself. This is not the time to say "Well, okay, but what if we make the word mean something else? Something less restrictive, maybe?".

What you're doing is like responding to FE people who say "the horizon is flat, checkmate globetards!" with this image


And saying "Aha! Look! That's not perfectly flat, there are bumps". That doesn't "help facilitate meaningful conversation". We all know what they mean by flat. Come on dude, this is just pointless pedantry. The contrast I am making is the horizon one sees on a clear day with the lack of one on a misty day. The issue with the latter is visibility. And on a FE where you've got thousands of miles of flat sea stretching in front of you visibility would always be an issue. You wouldn't have a horizon a few miles away beyond which you only see the sky. I think we agree it isn't visibility, you claimed it was "waves, usually" and ignored the part of my previous post where I explained why that can't be true if you're at any altitude more than a few meters.

[SteelyBob]

Aside from that, what do you think causes a visible horizon? If the edge of the earth is many thousands of miles away, what exactly are we looking at when we see the horizon?

Please familiarise yourself with basic FET before attempting to debate it.

Whilst the others are addressing your frankly bizarre response to the horizon picture stuff, I’ll draw attention to the fact that you didn’t respond to my question above. All you did was indicate that the question was too basic for you to grace with an answer. However, as you well know, the source you would offer for this ‘basic FET’ information is both incomplete and contradictory. It contains a range of views on what the horizon is or might be, and they can’t all be true at the same time. So asking you what you think isn’t me lazily trying to get you to describe the wiki to me, it is rather me trying to understand precisely what it is that you think. If you are a bendy light proponent, for example, then you are taking a completely different view to the things-lower-as-they-get-more-distant / modified vanishing point / limits of human vision etc stuff.

Hiding behind a ‘do your research’ line does your argument no favours - you just look like you’re ducking the question. So, again, what exactly do you think is going on at the horizon? What exactly are we looking at?

[Action80]

Aside from that, what do you think causes a visible horizon? If the edge of the earth is many thousands of miles away, what exactly are we looking at when we see the horizon?

Please familiarise yourself with basic FET before attempting to debate it.

Whilst the others are addressing your frankly bizarre response to the horizon picture stuff, I’ll draw attention to the fact that you didn’t respond to my question above. All you did was indicate that the question was too basic for you to grace with an answer. However, as you well know, the source you would offer for this ‘basic FET’ information is both incomplete and contradictory. It contains a range of views on what the horizon is or might be, and they can’t all be true at the same time. So asking you what you think isn’t me lazily trying to get you to describe the wiki to me, it is rather me trying to understand precisely what it is that you think. If you are a bendy light proponent, for example, then you are taking a completely different view to the things-lower-as-they-get-more-distant / modified vanishing point / limits of human vision etc stuff.

Hiding behind a ‘do your research’ line does your argument no favours - you just look like you’re ducking the question. So, again, what exactly do you think is going on at the horizon? What exactly are we looking at?

I believe Pete is not hiding behind a "do your research," line.

Indeed, I believe you continue to exhibit all the characteristics of person having zero clue concerning FET (or RET) for that matter.

As I stated before, you deny FE so much, there is no possible way you could ever describe what it looks like.

[SteelyBob]

[
I believe Pete is not hiding behind a "do your research," line.

Indeed, I believe you continue to exhibit all the characteristics of person having zero clue concerning FET (or RET) for that matter.

As I stated before, you deny FE so much, there is no possible way you could ever describe what it looks like.

You’re of course welcome to believe whatever you want. The fact is that I asked him a straight question, which he refused to answer. What is also a matter of fact is that the various ideas around horizons offered up in the wiki cannot all be true simultaneously. It is therefore not unreasonable to ask somebody what they think is going on, as the matter is clearly not internally settled in the FE community, much like the many maps that are offered up.

Maybe you’d like to answer?

[Pete Svarrior]

As secretagent says, when someone says a knife is sharp no-one is going to get an electron microscope out, note the bumps at that level and say "well akchooalley...".

And I already explained why this desperate defence is non-applicable here. Why waste your time restating it instead of addressing the issue?

an edge detection algorithm

lmao

You've already conceded there's a difference and that's the point I have been making.

There is a difference - it's just not the difference you need for your argument to work.

But I do also recognise that we live in reality, not a mathematically perfect world.

That's progress. Baby steps. Now, revise your argument to match reality.

The issue here is that the moment you remove the supposed perfection, and introduce the fact that the visible horizon is not the true horizon, your argument no longer differentiates FE from RE.

What you're doing is like responding to FE people who say "the horizon is flat, checkmate globetards!" with this image

I am doing nothing of the sort, and I am asking (no longer politely) that you stop putting words in my mouth. Address what I said, not what you made up during your last deliberation on the shitter.

All you did was indicate that the question was too basic for you to grace with an answer.

This is patently dishonest. For the reference of those watching at home, here is my answer:

"It's not sharp or clear "in the way" that it is blurry and gradual. This is not a complex statement, so there's not much to elaborate on."

Even though I remarked that this is not a complex statement, I made my best effort to clarify it for you. I also explained why it's difficult to work with your question as-is. If you'd like to dig deeper, you're welcome to ask more meaningful follow-up questions. However, if your preference is to lie about what I said and insist that I somehow refused to answer you, please understand that I won't be wasting more time on you.

[SteelyBob]

All you did was indicate that the question was too basic for you to grace with an answer.

This is patently dishonest. For the reference of those watching at home, here is my answer:

"It's not sharp or clear "in the way" that it is blurry and gradual. This is not a complex statement, so there's not much to elaborate on."

Even though I remarked that this is not a complex statement, I made my best effort to clarify it for you. I also explained why it's difficult to work with your question as-is. If you'd like to dig deeper, you're welcome to ask more meaningful follow-up questions. However, if your preference is to lie about what I said and insist that I somehow refused to answer you, please understand that I won't be wasting more time on you.

Sorry Pete, but that's not the reply to my question - I think you've muddled up which conversation was which. I said:

I think that has rather more to do with the fact that his camera is clearly focussing at a point nearer than the horizon than it does with the shape of the earth. If we were to take a similar shot with the focus at the 'horizon' it would be a lot crisper.

Aside from that, what do you think causes a visible horizon? If the edge of the earth is many thousands of miles away, what exactly are we looking at when we see the horizon?

This was your reply:

Please familiarise yourself with basic FET before attempting to debate it.

Let's at least agree on what the disagreement is.

[AATW]

There is a difference - it's just not the difference you need for your argument to work.

My argument is that there is a difference between the observation of a horizon when visibility is less than the distance to said horizon and when visibility is greater than that distance.

When visibility is greater than the distance to the horizon you see a distinct horizon line. And yes, yes, it's not a perfect straight line. When you zoom in you can see waves and ripples. And it's not perfectly clear as it would be if we didn't have an atmosphere, there's a bit of atmospheric haze. Refraction is also a thing and that can make the apparent horizon different from the geometric one. So yes, all those things exist. But none of that changes the basic argument or observation. Even in that zoomed in view above, you can see the waves but it's very clear where the horizon is, there's no gradual fade between sea and sky.

On a foggy day when visibility is less than the distance to the horizon it's completely different. You can't see the horizon, the sea just fades out. There's no clear line between the sea and sky.

And the reason for all this, according to RET, is that the horizon is a physical thing. The earth is a globe, so the sea curves away from the observer. The horizon line is the furthest you can see over that curve as per my diagram. With FE why would there even be a horizon line? There's a thousand miles of flat sea in front of you, why can you only see the first few miles? You could invoke waves if you're close to sea level, if you're up a hill as I was when I took that other photo above, then that explanation doesn't work. You're higher than the level of the waves and thus able to see over them, yet there's still a clear horizon line - visibility permitting.

My argument is that on a FE the observation would surely always be more like the foggy day image. The visibility would always be lower than the amount of sea which should be visible, so the sea would fade out gradually. The whole reason for the clear distinction between sea and sky on a RE is that the sea curves away from you, preventing you from seeing more sea. On a FE that reason doesn't exist.

[Pete Svarrior]

I think you've muddled up which conversation was which.

Well, that's not quite right either. You asked multiple questions, and then expressed that you were unhappy with my reply to "your question" - seemingly leaving me to just guess which one you might mean. I responded to two of your posts: one, in which you asked a singular question, and which I criticised; and one, in which you asked multiple questions that indicated you hadn't done your reading - for which I provided you with a quick reminder of the rules and ignored the matter further.

I hope you can see why when you complained about "the question", the more recent post with a singular question seemed more intuitive than an older one with multiple questions, and one which you know better than to waste our time with.

Now, I admit I didn't pay much attention to your follow-ups, in which you repeatedly re-asked the questions after I told you not to even do it once. So, a more forceful reminder: read up on the basics before posting here again; do not spam the debate forums with complains that you failed to read the Wiki. This is a prerequisite to you using this forum.

My argument is that there is a difference between the observation of a horizon when visibility is less than the distance to said horizon and when visibility is greater than that distance.

Quite. The difference is that one of these occurs in reality.

When visibility is greater than the distance to the horizon you see a distinct horizon line. And yes, yes, it's not a perfect straight line.

No, sorry, that's not it at all. Again, this is you just arguing with RET. Under RE assumptions you will never, in your lived experience, end up in a scenario where the true horizon is clearly visible as a distinct line. The only question is whether the gradient is steep and pronounced, or not-so-steep.

And it's not perfectly clear as it would be if we didn't have an atmosphere, there's a bit of atmospheric haze. Refraction is also a thing and that can make the apparent horizon different from the geometric one. So yes, all those things exist. But none of that changes the basic argument or observation.

Indeed - your argument fails much sooner than that. All these factors just make it more obvious and readily experienced.

Even in that zoomed in view above, you can see the waves but it's very clear where the horizon is, there's no gradual fade between sea and sky.

This incorrect. The limits of your perception are none of my concern - you can assist yourself with tooling if you need to. You have yet to post a single photo in which there is no gradual fade between the sea and the sky, except for ones in which the visual obstruction occurs much closer than the location of the true horizon.

And the reason for all this, according to RET, is that the horizon is a physical thing. The earth is a globe, so the sea curves away from the observer. The horizon line is the furthest you can see over that curve as per my diagram.

You're still wrong about this, no matter how many times you repeat this fallacy. You're mistaking the true horizon for something that you can actually see on Earth. You are right that in theory, on a perfect sphere with no atmospheric conditions, you would be able to perceive the true horizon, and it would be pretty close to a sharp line. However, you also concede that we do not live on a perfect sphere with no atmospheric conditions. What you see is not the true horizon - it's much closer to you than this hypothetical limit.

With FE why would there even be a horizon line?

For the same reason as RE; as long as we're not talking about the hypothetical true horizon, but rather the real intersection of the sea and sky that you can see, and which you provided a photograph of.

My argument is that on a FE the observation would surely always be more like the foggy day image.

This is misguided. You seem to think that these are two different scenarios. They aren't - they're two manifestations of the same phenomenon, to two different extents.

The visibility would always be lower than the amount of sea which should be visible, so the sea would fade out gradually.

It does - as you helpfully supported with photographs.

The whole reason for the clear distinction between sea and sky on a RE is that the sea curves away from you, preventing you from seeing more sea.

You keep trying to provide reasons for a distinction which doesn't exist. I can't force you to learn about how RET works, but you're really not gonna do a good job of either defending or disputing it when you're so misguided about its basic properties.

[SimonC]

Right. Yeah, that's roughly the level of hand-waving I was expecting here. "Well, y'know, it isn't sharp, but it's sharp."

As secretagent says, when someone says a knife is sharp no-one is going to get an electron microscope out, note the bumps at that level and say "well akchooalley...".
Put any of the pictures I've posted through an edge detection algorithm and it's going to show you a clear horizon line unless you make it so sensitive then it literally only detects a line if the two adjacent pixels are completely different. Compare and contrast with the foggy day image where you're not going to get an edge. You've already conceded there's a difference and that's the point I have been making.

AATW claims, in no uncertain terms (despite your attempt at muddying the subject) that the absence of one would disprove FET. He backs this up with diagrams, which clearly show that, in his view, the horizon in RET would be a mathematically perfect divide. His side-view illustrates a point intersection.

This is all accurate. But I do also recognise that we live in reality, not a mathematically perfect world. My diagram shows the situation, but of course in reality the sea isn't perfectly flat, there are some atmospheric effects. I'm using the word sharp to contrast the horizon on a clear day with a foggy day where the sea just fades out.

He is correct - this would disprove FET. What he misses is that the absence of one would also disprove RET, and reality itself. This is not the time to say "Well, okay, but what if we make the word mean something else? Something less restrictive, maybe?".

What you're doing is like responding to FE people who say "the horizon is flat, checkmate globetards!" with this image


And saying "Aha! Look! That's not perfectly flat, there are bumps". That doesn't "help facilitate meaningful conversation". We all know what they mean by flat. Come on dude, this is just pointless pedantry. The contrast I am making is the horizon one sees on a clear day with the lack of one on a misty day. The issue with the latter is visibility. And on a FE where you've got thousands of miles of flat sea stretching in front of you visibility would always be an issue. You wouldn't have a horizon a few miles away beyond which you only see the sky. I think we agree it isn't visibility, you claimed it was "waves, usually" and ignored the part of my previous post where I explained why that can't be true if you're at any altitude more than a few meters.

Am guessing you didnt take that pic but you are accepting it as face value. Its one of the most faked images I have seen - cant you see that? Or does your indoctrinated mind not allow you to? In fact the more I look at it the more my sides split.
Its too close up to be real. If the photographer was that close there wouldnt be a curve. Its a joke. Theres plenty others like this but ask anyone who has tried to film 'over the horizon' how difficult it is.