i've been mulling this one over for a while.
I thought that as, from our perspective, the horizon is a circle, with our viewpoint being the radius, wouldn't the edge of the circle, from our point of view, be flat.
The horizon would only be curved if there was a difference in altitude of the points on the horizon. (As, for the frame of reference that we have on the ground, the earth is essentially flat)
A way to see this is when looking at a theoretical ocean. Theoretical as there is no tides, and no obstruction on the horizon.
If one were to look directly north, and swivel clockwise, the horizon should remain an unbroken line.
This is demonstrable. So, if we see that, in our frame of reference, the horizon is flat, then flat-earthers can no longer use this as proof of the earths flatness.
Thoughts?
Question: If I am wrong (not unlikely

), then what form would the horizon take on a theoretical perfect sphere?
And I am not assuming that the earth is a sphere, I have proof. Sunsets. I have not seen any reason or explanation of how this would occur on a flat earth.