The first time I stumbled on the flat earth societys website I really, really could not tell. They even had complicated looking physical models of how gravity etc. works on a flat earth etc. My conclusion was, that most did just trolling. But now after I met some real flat earthers .. I am not so sure anymore. They were also not plain stupid. Just far out and very ignorant. So they build a lot of complex logic on a false axiom.

They reminded me a lot of the classical "science" of bible theology. Where you take something ridiculus word for word - and then build a a complex stringent and logical philosophy above it. (with marxism I had similar experiences)