So the thread is badly named. Sue me.
I just had a thought; post-modern relativism.
Alrighty flat-earthers, listen up, because this might just be the bullshit theory that you can use as a lifeboat in these horribly unfriendly, and all-too-well charted seas of Logic, Reason, and Scientific Fact.
Essentially, post modern relativism states that (roughly paraphrased):
1) The unisvers does not physically exist
2) We only percieve things in our own "reality construct", and have no way of experiencing them from another's point of view
3) As things don't truly exist, our only understanding of them is through our experiences of them, which cannot, necessarily, be stated to relate to another's experiences.
Ergo, all views of the world are equally valid. The earth is flat, if you believe it's flat.
Here's the catch though; it's also round if you think it's round.
Granted it's not the round-earth smashing theory you're looking for, but it's probably the closest you're gonna get.
So, opinions?