The fact you thought the Earth even might POSSIBLY be flat, is PROOF POSITIVE: can ONLY MEAN no one has EVER explained how longitude and latitude

As i explained in the last comment - the coordinate system we ascribe/use is entirely arbitrary. It has nothing to do with the shape of the world. People are also encouraged to make this erroneous conflation with timezones. I find it patently absurd and plainly nonsensical - just look at the statements :

The world has to be spherical because "timezones".

or in your case

The world has to be spherical because "geometry"/"longitude and latitude".

It's doesn't make a lick of sense.

and learn to sail and fly.

Yes, sailing and flying exist. No, this doesn't prove the world is spherical... Why on earth would it?!

The world was decided to be spherical (also arbitrarily) long before longitude and latitude. They played absolutely no part in determining the shape of the world - then and now. "Your" entire argument (your is in quotes because it was given to you, and is not your own!) is retroactively backfilled/contrived.

We both agree that latitude and longitude work. We can also agree that if the world is flat that, most likely, the known sizes for the latitude lines in the "southern hemisphere" are wrong - as well as the known distances between longitude lines.

Many people think similar things about maps. Maps prove this and that about the shape of the world.

But maps and the coordinate systems on them are merely tools for travel. They don't contain (or depend on) the shape of the world, nor do they need to! When they work, we use them - when they don't we change them. The world, and its shape, remains the same.

The real question is, if the world really were flat (or at least not spherical the way we are taught), would you want to know it? Even if knowing the truth brought you ridicule, and even exile?

The fact you thought the Earth even might POSSIBLY be flat, is PROOF POSITIVE: can ONLY MEAN no one has EVER explained how longitude and latitude

As i explained in the last comment - the coordinate system we ascribe/use is entirely arbitrary. It has nothing to do with the shape of the world. People are also encouraged to make this erroneous conflation with timezones. I find it patently absurd and plainly nonsensical - just look at the statements :

The world has to be spherical because "timezones".

or in your case

The world has to be spherical because "geometry"/"longitude and latitude".

It's doesn't make a lick of sense.

and learn to sail and fly.

Yes, sailing and flying exist. No, this doesn't prove the world is spherical... Why on earth would it?!

The world was decided to be spherical (also arbitrarily) long before longitude and latitude. They played absolutely no part in determining the shape of the world - then and now. "Your" entire argument (your is in quotes because it was given to you, and is not your own!) is retroactively backfilled/contrived.

We both agree that latitude and longitude work. We can also agree that if the world is flat that, most likely, the known sizes for the latitude lines in the "southern hemisphere" are wrong - as well as the known distances between latitude lines.

Many people think similar things about maps. Maps prove this and that about the shape of the world.

But maps and the coordinate systems on them are merely tools for travel. They don't contain (or depend on) the shape of the world, nor do they need to! When they work, we use them - when they don't we change them. The world, and its shape, remains the same.

The real question is, if the world really were flat (or at least not spherical the way we are taught), would you want to know it? Even if knowing the truth brought you ridicule, and even exile?