W3C home > Mailing lists > Public > semantic-web@w3.org > October 2010

Re: Are literals owl:Things?

From: Jesse Weaver <weavej3@rpi.edu>
Date: Thu, 14 Oct 2010 12:02:08 -0400
Cc: Toby Inkster <tai@g5n.co.uk>, Antoine Zimmermann <antoine.zimmermann@deri.org>, semantic-web@w3.org
Message-Id: <6B4C8909-D9E3-4961-BA0A-2E064BDFBB72@rpi.edu>
To: Jeremy Carroll <jeremy@topquadrant.com>
That may be according to most (or all known) implementations, but I  
don't think that's true for the DL-based semantics of OWL 2.  From [1]:

* \Delta_I is a nonempty set called the object domain.
* \Delta_D is a nonempty set disjoint with \Delta_I called the data  
domain ....
* \cdot^C is the class interpretation function ....
      * (owl:Thing)^C = \Delta_I
* \cdot^{DT} is the datatype interpretation function ....
      * (rdfs:Literal)^{DT} = \Delta_D

Since \Delta_I and \Delta_D are disjoint, then (owl:Thing)^C and  
(rdfs:Literal)^{DT} are disjoint.

[1] http://www.w3.org/TR/2009/REC-owl2-direct-semantics-20091027/#Interpretations

Jesse Weaver
Ph.D. Student, Patroon Fellow
Tetherless World Constellation
Rensselaer Polytechnic Institute
http://www.cs.rpi.edu/~weavej3/index.xhtml

On Oct 14, 2010, at 11:41 AM, Jeremy Carroll wrote:

> Yes
>
>
> The way to answer this is to assess the truth of
>
> rdfs:Literal rdfs:subClassOf owl:Thing .
>
> In some systems this is a syntax error.
> In some systems this is necessarily true.
> In no systems is this false.
>
> Jeremy
>
>
>
>
>
Received on Thursday, 14 October 2010 16:02:20 UTC

This archive was generated by hypermail 2.4.0 : Tuesday, 5 July 2022 08:45:20 UTC