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

From: Waqar Hasan <hasan@dbwizards.com>
Date: Sun, 27 Apr 2003 18:47:37 -0700
To: "Richard H. McCullough" <rhm@cdepot.net>, <www-rdf-interest@w3.org>
Message-ID: <BIEJIHBDAGGDGJEKMJLLGEBMCBAA.hasan@dbwizards.com>
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 21:47:46 GMT

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