Well, that's what the story is supposed to be about, right?

So, um, dimension, huh? A fascinating subject. I'm sure I could write a whole novel about it, if only I could come up with an idea. Let's see... Oh, I've got it! There's this square, right, and he lives on a plane, and then he's visited by a sphere... No, wait, that's been done. Damn! Well, I guess I'll just have to think of something else.