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Re: RDF -- venn diagram for resources, literals, properties, statements?

From: Richard H. McCullough <rhm@cdepot.net>
Date: Sun, 27 Apr 2003 19:03:04 -0700
Message-ID: <002401c30d2a$6a74e8a0$bd7ba8c0@rhm8200>
To: "Waqar Hasan" <hasan@dbwizards.com>, <www-rdf-interest@w3.org>
Everything is a Resource.
Everything is either a Class or an Individual.
All classes are subclasses of Resource.

http://rhm.cdepot.net/doc/properSubClassOf.html
is available now.
============ 
Dick McCullough 
knowledge := man do identify od existent done;
knowledge haspart proposition list;

  ----- Original Message ----- 
  From: Waqar Hasan 
  To: Richard H. McCullough ; www-rdf-interest@w3.org 
  Sent: Sunday, April 27, 2003 6:47 PM
  Subject: RE: RDF -- venn diagram for resources, literals, properties, statements?


  Look forward to an explanation of why these answers follow -- presumably they are axioms or are derivable
  from axioms. Will check your URL tomorrow.

  For example for (a), the 4th axiom in the RDF model (http://www.w3.org/TR/1999/REC-rdf-syntax-19990222/ Section 5)
  states:

  There is a set called Statements, each element of which is a triple of the form {pred, sub, obj} where pred is a property (member of Properties), sub is a resource (member of Resources), and obj is either a resource or a literal (member of Literals).

  This makes it sounds like Literals are disjoint from Resources. How do you infer Literals to be a subset of Resources?

  -Waqar


    -----Original Message-----
    From: Richard H. McCullough [mailto:rhm@cdepot.net]
    Sent: Sunday, April 27, 2003 3:56 PM
    To: Waqar Hasan; www-rdf-interest@w3.org
    Subject: Re: RDF -- venn diagram for resources, literals, properties, statements?


    The answers are:
    1. false
    2. true
    3. false
    4. true

    The relevant taxonomy is
    Resource
        Literal
        Property
        Statement
    In this taxonomy, the species are mutually exclusive, 
    but not exhaustive.

    For further explanation, I'm writing up some notes on
    subClassOf inferences, which will be available 
    tomorrow at
    http://rhm.cdepot.net/doc/properSubClassOf.html
    ============ 
    Dick McCullough 
    knowledge := man do identify od existent done;
    knowledge haspart proposition list;

      ----- Original Message ----- 
      From: Waqar Hasan 
      To: www-rdf-interest@w3.org 
      Sent: Sunday, April 27, 2003 2:33 PM
      Subject: RDF -- venn diagram for resources, literals, properties, statements?


      I am trying to understand the Venn diagram for the following sets
      used in the RDF data model (http://www.w3.org/TR/1999/REC-rdf-syntax-19990222/ Section 5)

      1. Resources
      2. Literals  
      3. Properties (proper subset of resources)
      4. Statements 

      I suspect the following are true and would appreciate either pointers to what in the spec makes them true or counter-examples:

      (a) No literal is a resource 

      (b) No property is a statement 

      (c) Some statements are resources others are not.

      (d) No literal is a statement 

      Thanks,

      - Waqar Hasan
Received on Sunday, 27 April 2003 22:03:49 GMT

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