HaloO, Jonathan Lang wrote:
If we make a point of highlighting the "set operations" perspective
You know that there are two sets involved. So which one do you mean?
and avoiding traditional type theory terminology (which, as Larry pointed out and TSa demonstrated, is very much inside out from how most people think), we can avoid most of the confusion you're concerned about.
Well, the type theory terminology has it all. You just have to be careful what you pick and how you combine the terms. "Sub" and "super" be it in class, role or type connotate an order that in fact is there as a partial order or preferably as a lattice. The rest is about choosing a syntax. I for my part can live happily with whatever flipping of (&) and (|) we settle on as long as I know to which set they apply. That being said I would think that prior art dictates (&) as meaning subtype creation. Which puts it in line with & for the all junction and && as logical connective. Note that the counterintuitive notation for pre-composed roles using | is gone. It still exists in the signatures, though. Regards, TSa. --
