At the end of the day, I'm saying that this Earth is as you perceive it-- flat! If you, and others, would like to challenge that and present a theory proposing that the Earth is, in fact, a spinning globe flying through the endless vortex of space around a giant nuclear fusion sphere, then go for it. Try and make it convincing this time.
Exactly, at the end of the day,
you're saying that the Earth is flat - Together with a fairly narrow collection of so-called free thinkers who did their utmost to molest the concept of free thinking, turning it into a BS carte blanche. In essence, I understand why and I actually endorse the thought experiment as long as you as intellectual adults nurse and acknowledge the fact that it's exactly that - An entertaining thought experiment.
As to whether or not I'm supposed to prove to you that Earth is round - That notion itself is quite a few steps ahead of what used to be an intellectual debate attributing core principals and concepts to rational thinking. First of those being supplying one single piece of evidence that comes just remotely close to nurishing any sort of sensible, rational doubt about "what we know" - Then, you carry on to build the foundation of what is to become a fully-fledged theory, ready to be backed up by evidence. Then you present all of the above as a whole, connecting the dots between observation (facts) and theory (explanation) and
THEN, but only then, are you eligible to draw the "burden of proof card".
Since none of that is remotely close to resembling reality just yet, the "burden of proof" card is a card that doesn't belong in the deck at all. Even if the burden of proof were on FET. There's nothing to suggest that FET has come close to discovering anything that could rise the slightest bit of doubt about the shape of the Earth. That's your task for now. Personal belief has no place in this realm, and you know that as well.