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skolems: visible differences?

From: Jeremy Carroll <jjc@hpl.hp.com>
Date: Mon, 10 Dec 2007 12:22:10 +0000
Message-ID: <475D2F72.5090208@hpl.hp.com>
To: "Web Ontology Language ((OWL)) Working Group WG" <public-owl-wg@w3.org>



Boris and Bijan, amongst others, seem to support the use of skolems for 
bnodes.

===

I think that this is an implementation detail, and hence not appropriate 
for a specification. Since Boris and Bijan *are* suggesting that it 
should be specified, I suspect I have misunderstood.

===
So I have some questions:
If we agree to specify the use of Skolems, what visible difference does 
it make (e.g. in terms of tests)

a) are Skolem constants permitted in a serialization of a ontology read 
in with bnodes?

b) would any document become consistent (or inconsistent) with bnodes as 
skolems, whereas it is inconsistent (or consistent) with bnodes as 
existentials

c) would any entailment (or non-entailment) with out bnodes in the 
conclusion, become a non-entailment (or entailment) with bnodes as 
skolems, as opposed to bnodes as existentials.

d)
Does the following entailment hold with bnodes as skolems:

_:a rdf:type owl:Thing

entails

_:a rdf:type owl:Thing

?

If yes, why?

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Any further hints as to why I may be misunderstanding would be helpful

Jeremy
Received on Monday, 10 December 2007 12:22:44 GMT

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