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Re: Issue #danc-04 add a triviallyTrue predicate

From: Dan Brickley <danbri@w3.org>
Date: Fri, 25 Apr 2003 12:23:27 -0400
To: connolly@w3.org
Cc: www-rdf-comments@w3.org
Message-ID: <20030425162327.GK12807@tux.w3.org>


Dan,

Could you explain in a bit more detail what you're asking for?
I'm having trouble understanding how an 'rdfs:triviallyTrue'
predicate might work.

http://lists.w3.org/Archives/Public/www-rdf-comments/2003AprJun/0085.html

>Consider adding to RDFS a triviallyTrue predicate;
>specification:
>
>   ?S rdfs:triviallyTrue ?O.
>
>is true for all ?S and ?O.
>
>Rationale:
>
>(1) jeremy's digital signature application needs
>to number bnodes
>
>(2) folks are asking for all uses of rdfs:comment
>to be vacuously true. This would provide that
>functionality.

In particular, I don't yet understand how this would relate to 
the rdfs:comment concern. Is the idea that it should be 
impossible to assert something false with an rdfs:comment 
in the predicate role of a statement?

(in which case, trivially true seems to be a class of 
properties...?)


On the rdfs:comment as 'trivially true' angle,
are you happy with folk saying:

<rdf:Description rdf:about="mailto:connolly@w3.org">
  <rdfs:comment>Unspeakably offensive comments here</rdfs:comment>
</rdf:Description>

or

<rdf:Description rdf:about="http://purl.org/dc/elements/1.1/title">
  <rdfs:comment>Father Christmas</rdfs:comment>
</rdf:Description>

...and these being held as truths by all RDF systems?

Can you make a case for including triviallyTrue in the RDF Core specs,
rather than (for eg) in a utility vocabulary of some kind published (eg)
as a Note? There are lots of neat things we _could_ add if we had the time,
eg. conventions for XHTML markup in comments, modelling of versioning etc.
Is there something about triviallyTrue that jumps it to the top of the 
wishlist?

Dan
Received on Friday, 25 April 2003 12:23:30 GMT

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