So if we are basing our beliefs on what we see, how do we choose between ice wall or no ice wall, south ice wall or north ice wall? Why pick which thing we believe in if we cannot see any of these things?
That depends on your beliefs. You are free to believe anything.
- If you want to believe there is a north ice wall, so be it.
- If you want to believe there is a south ice wall, so be it.
- If you want to believe there is no ice wall, so be it.
For me for example, I believe that there is no ice wall anywhere because the earth is round => I believe the earth is round because everything I've learned and observed so far confirm the round earth theory in every way => The round earth theory does not include an ice wall anywhere => So I don't believe there is an ice wall.
You can believe that the earth is flat, it's your right. But you can not argue that using scientific facts, and that's the problem I have with most of flat-earthers today. They try to prove the earth is flat using false or vague scientific and physic facts. Most of the proofs are also explained using such argument as "well we don't know how it works today". But for the round earth, we know how it works. We know it works because everything is tested, and put into action. Satellites, rockets, airplanes, navigation works because we know the earth is round, spinning, orbiting the sun, etc...
Today, there are no proof of the ice wall (south or north). But there are proof of the non-existent ice wall (photographs and videos of the earth). You can believe those photographs and videos to be true, or fake, I don't care. The only "proof" we have for the ice wall is : "well of course we can't proof there is an ice wall, because it is guarded by thousands of ships". That argument does not work for me. It's exactly like saying : "right now, next to you, there is a huge invisible and immaterial dragon with an invisible immaterial unicorn on top. But I can not prove it to you, because it's invisible and immaterial."
You can think differently, that's your right. But if you want to debate with someone with your beliefs, either you say nothing (because there is not debate to have, you believe in it you believe in it, period - like religion), or you use actual facts to prove what you say.
I hope all of that is understandable. English is not my mother tongue, but I try to do my best
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