Hey guys! So, kinda hard to phrase but essentially what I’m wondering is this: Let’s say I’m living in a town somewhere some thousands of years ago. I would know that there’s the “land” and that there’s the “sky,” and that would be about the height of my knowledge and understanding of how the realm that I exist in works. I wouldn’t even be able to understand or wrap my head around the concept of “planets,” or “solar systems” or anything like that - I certainly wouldn’t think the earth is round, or that the concept of a “planet” was even a thing. But then thousands of years later apparently people noticed that boats disappeared from the bottom up when they got far enough out into the ocean, so that (if I remember correctly) was how some ancient people knew the earth was round. But like, how in the world did they come to that conclusion? The idea that the “land” that I exist on - and for all I know is just an unending flat plane - is a round object would make absolutely no sense to me, and would certainly not be the first explanation I come up with for phenomena like boats disappearing over the horizon, or the difference between shadows cast by poles in Syene and Alexandria (which I believe was also another way people found out the Earth was round?). And then, how did we discover that the earth was a “planet” and that it wasn’t the only solid object of land that existed? Because in a world where nobody ever talks or learns anything about “space” or “planets,” I’d think that concept would just be absolutely bizarre and make no sense. I know I probably phrased that badly, but man I’m so curious about that because it seems like it would have been such a weird concept to even come up with back then.