Pratchett's L-space library metaphor is extremely apt for describing the mind when added to Wittgenstein's.
I scan across the bookshelf, I notice that the dimensionality changes depending on how I look at it. The ways things can connect is different depending on which idea, and often also in what perspective I look at that idea.
There are rules, of course, and these rules are the same everywhere. The number of dimensions simply isn't one of them.