For bad arguments in that class, the feeling I get is the same sense of emptiness that I get when I think about a closed, opaque box that I know is empty. There's just nothing useful there, the sentence is a shell with no logic inside.

That's a very lucky response. I visualise something like a broken, mashed-up machine made of human belief and longing, flailing and bleeding as it tries to keep running. It's really very horrible. That's what determined stupidity looks like.

(wow, that's icky. It's also true. I slightly wish I hadn't realised that's what I've been picturing. Mostly in a dim sodium-yellow light rather than full colour, thankfully.)