On 3/21/13 12:26 PM, Michel Dumontier wrote:
my problem largely lies in the "identifies" relation between a URI and a document

Yes, but in the context of RDF based Linked Data, a single HTTP URI can in fact denote one thing in a manner to uses indirection (implicit or explicit) to identify a description document for its referent, leaving the "describes" (which is owl:inverseOf wdrs:describedby) relation as the final part of the semiotic triad.

Anyway, my illustration isn't cast in stone, I am happy to tweak the diagram. For instance, what about replacing "identifies" with "locates" which them meshes nicely with the "L" in URL (a Locator/Address) ?

Kingsley
. and generally, that it wouldn't represent as a triad, but a bilateral relation between an entity (identified by uri) and a document (which refers or describes it).

m.

On Thu, Mar 21, 2013 at 11:05 AM, Kingsley Idehen <kide...@openlinksw.com <mailto:kide...@openlinksw.com>> wrote:

    On 3/21/13 10:57 AM, Michel Dumontier wrote:
    Kingsley,
     I think you raise good points. I also nominally speak of
    entities, their attributes and the relations that hold between
    them. But I think your diagram is somewhat misleading. URIs do
    denote (can stand in the place of) entities of interest in order
    to refer to and/or describe them. If you separate the identifier
    from what it intends to identify, then you'll need another
    identifier for the object of interest (and recurse). Hence, a
    information containing object (document, graph, file, etc) may
    refer to our entity of interest by some label. the document could
    refer to it in some statement, or may contain elaborate
    descriptions about it.  But in no way does a document directly
    refer to a real world object (in does so indirectly through some
    token - an english name, identifier or uri, etc).

    m.

    I don't see how my illustration conveys anything contrary to what
    you've just outlined. The parts:

    1. An entity (in this case a Person) -- a real-world or non Web
    realm entity
    2. An identifier that denotes the Person -- e.g., a URI
    3. A document that describes the person -- e.g. a Document
    comprised of RDF model based content in the form of an description
    graph (you can have many of these, each denoted with its own
    URI-URL based identifier).

    Note: URI-URL is how I convey the fact that you can denote a Web
    Document using its URL. Thus, Turtle, RDF/XML, RDFa+(X)HTML etc..
    documents (each with their own URI-URLs) can each be comprised of
    graphs describing the same entity.

    Kingsley




    On Thu, Mar 21, 2013 at 10:27 AM, Kingsley Idehen
    <kide...@openlinksw.com <mailto:kide...@openlinksw.com>> wrote:

        On 3/20/13 10:58 PM, David Booth wrote:

        Thus, to be very clear, under the existing RDF Semantics
        specification, a given URI does **not** necessarily map to
only one resource.

        True, but I don't think the statement above always provides
        the clarity intended.

        "Resource" is a synonym of "Entity" as *now* clearly stated
        in the latest RDF concepts guide [1]. Once we get over the
        conflation inherent in "Resource" and look towards "Entity"
        the issue starts to get much clearer, as exemplified by RDF
        based Linked Data [2] and its specific use of URIs to denote
        "Entities" while also identifying their "Descriptor Documents".

        All "Resources" aren't of the same medium. The Web, Internet
        are mediums distinct from the medium we *refer to* as the
        real-world. Thus, the claim that everything is a "Resource"
        without medium specificity is one of the ultimate recipes for
        unproductive debate and confusion, as a zillion mail threads
        over the years have demonstrated.

        In the context of RDF, a URI denotes an Entity.
        In the context of RDF based Linked Data, a URI denotes an
        Entity in a manner that enables it resolve to a Web Document
        (denoted by its own URI which is usually a URL) that
        describes the denoted entity (aka. URI referent) .


        Links:
        1.
        http://www.w3.org/TR/rdf11-concepts/#resources-and-statements
        -- showcasing the critical "Resource" fix
        2. http://twitpic.com/cbk8ul -- illustrating HTTP URI duality
        and the Semiotic triangle .


--
        Regards,

        Kingsley Idehen 
        Founder & CEO
        OpenLink Software
        Company Web:http://www.openlinksw.com
        Personal Weblog:http://www.openlinksw.com/blog/~kidehen  
<http://www.openlinksw.com/blog/%7Ekidehen>
        Twitter/Identi.ca handle: @kidehen
        Google+ Profile:https://plus.google.com/112399767740508618350/about
        LinkedIn Profile:http://www.linkedin.com/in/kidehen







-- Michel Dumontier
    Associate Professor of Bioinformatics, Carleton University
    Chair, W3C Semantic Web for Health Care and the Life Sciences
    Interest Group
    http://dumontierlab.com


--
    Regards,

    Kingsley Idehen     
    Founder & CEO
    OpenLink Software
    Company Web:http://www.openlinksw.com
    Personal Weblog:http://www.openlinksw.com/blog/~kidehen  
<http://www.openlinksw.com/blog/%7Ekidehen>
    Twitter/Identi.ca handle: @kidehen
    Google+ Profile:https://plus.google.com/112399767740508618350/about
    LinkedIn Profile:http://www.linkedin.com/in/kidehen







--
Michel Dumontier
Associate Professor of Bioinformatics, Carleton University
Chair, W3C Semantic Web for Health Care and the Life Sciences Interest Group
http://dumontierlab.com


--

Regards,

Kingsley Idehen 
Founder & CEO
OpenLink Software
Company Web: http://www.openlinksw.com
Personal Weblog: http://www.openlinksw.com/blog/~kidehen
Twitter/Identi.ca handle: @kidehen
Google+ Profile: https://plus.google.com/112399767740508618350/about
LinkedIn Profile: http://www.linkedin.com/in/kidehen




Attachment: smime.p7s
Description: S/MIME Cryptographic Signature

Reply via email to