Stick with RDFS or switch to OWL

[escowles]

There is a proposal to switch from encoding the core ontology in RDFS and to use OWL instead because it is more expressive and can encode things like pcdm:hasMember and pcdm:memberOf being reciprocal properties.

Should we switch to encoding the core ontology in OWL?

See #53 for preliminary discussion.

[no-reply]

but I get your initial point about RDFS being sort of a superset. It is because everything is more... not sure the word... descriptive/well defined/granular. Yes?

It's sort of counter-intuitive. Because RDFS is less descriptive, its universe includes more things---specifically, all the things which OWL's universe excludes because they won't support the kind of reasoning desired (those things which are both instances and classes, etc...).

But I also think this is not an emacs vs vim argument. There are things that you can do in OWL you can't do in RDFS.

Agreed.

On the other hand, this is cutting a little close to the kind of holy war Rob refers to. Apologies for my part in that.

@DiegoPino:

reads on this side also condescending.

Sorry. My intention was to assume good faith. Instead I got snippy. Thanks for your continued efforts, here.

[cmharlow]

Glad to see we are breaking this out into new tickets with specific restrictions / what we are not doing in rdfs now that we'll want to add (and using that to guide, or not, to OWL or other). Thanks all.

I'll keep my above doc up to date for those who care/want a cheat sheet of restrictions mentioned so far, but this is what I have somewhere brought up in discussions, notes or other:

• Property Inverses in PCDM - now a ticket
• Disjointness of Core Classes in PCDM
• Property Domain/Ranges in PCDM (specifically, using Unions of Classes to explicitly say PCDM:Collection u PCDM:Object instead of just ore:Aggregation)
• Allow users to define their own valid constructs - gets into if one should use OWL anyway to validate or external logic languages, technologies, other
• Capture Model Restrictions/Behaviors in the PCDM Ontology instead of the Applications, which I think is a higher level use case requiring further analysis of the PCDM docs, the Hydra docs, and applications to break out what is captured there that should be in the model
• Improved inferencing generally (pulled from comments like 'To be able to make inferences, inverse properties, graph traversal with precomputed paths' which also covers a bit of the above)

Happy to collect/discuss others proposed restrictions, action items, etc.

[ruebot]

@cmh2166 thanks for all this Christina!

[cmharlow]

@ruebot it beats dealing with bibframe. ;-)

[azaroth42]

Propose closing the issue.

[ruebot]

@azaroth42 do you have a proposed conclusion to close it with? Or just close it for now, and re-open it later if need be?

[azaroth42]

I propose closing because it's not an issue that we can resolve without use cases and more explicit requirements, hence the holy war nature of the discussion. We've agreed above to file new issues with actual requirements and proposed modifications, and hence this issue is unnecessary.

[cmharlow]

I think we've gathered the cases we can from this and can proceed based off those (and other, more specific cases as they surface in other discussions). So I'm good with closing this issue.

[DiegoPino]

@cmh2166 thank you very much for your work on this. I took some distance of this thread, mainly because i was told i was bringing too much more passion into the discussion and that was not helping too much. I highly appreciate your documentation and also the way you acted as "sanitising middleware" human-being here. 👍 thanks again