An interesting question/debate...

[Oblio]

I will say it to you one more time. If you hadn't been taught that the earth is round. What would make you think it is on a day-to-day basis? Most civilizations thought the world was flat at some time, Our perspective of the earth is that it would be flat.

Eratosthenes, b 276 BC calculated the circumference of the Earth to within 2.5%. Granted, there were likely many who thought the world was flat before this. But we (sans Flat Earthers) have known, through experiment, for millennia, that it is not.

Earth's circumference - Wikipedia

en.wikipedia.org