Go to the seaside. Look at the horizon. ?. Proved that earth is not flat! This is one of the dumbest conversations to have in 21st century lmao.
Look out over the ocean and the horizon is perfectly flat, what are you smoking dude?
Go out into the water, to a depth where your eye is centered at the level of the water, and look at the horizon. Where is the horizon located then? Right at eye level, right?
If you concentrate on straight ahead, you can't see the boat at the horizon no matter how close it is to you. Sure, part of your eye might see the nearby boat because you have peripheral vision. But the part of your eye that looks straight out at the horizon will never see the boat, because the horizon is exactly at the center of your eye.
The point is that when you look straight out at 90 degrees to the direction of gravity (density for FE people) you will see less and less of the earth and things on the earth, depending on the distance. But if you lessen the angle, gradually, to less than 90 degrees, you will see everything between yourself and the horizon.
So, it is not the horizon rising to meet your eyes. Rather it is your eyes lowering to meet the horizon... or not lowering to not meet the horizon.
