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Klyne Contexts: 5.2 Contexts as statements

From: Jonas Liljegren <jonas@rit.se>
Date: 23 Nov 2000 11:38:36 +0100
To: Graham Klyne <GK@Dial.pipex.com>
Cc: RDF interest group <www-rdf-interest@w3.org>, rdf@uxn.nu
Message-ID: <871yw3m0r7.fsf@astral.paranormal.se>
Hi!  I'm finaly started reading your page [1].

There seems to be an error in section 5.2.1.1:

I believe C36 and C37 should point at S9 and S10 respectively.


Further.  If I understand correctly:  The context can be used for
inferencing statements.  If all the rdfc:assumes statements are
asserted, all the rdfc:asserted statements will also be asserted.  But
that means that you can't mix two inference rules as done in the
example:

      C31:  [LAO] --rdf:type------> [rdfc:Context]
      C32:  [LAO] --rdfc:assumes--> [S5]
      C33:  [LAO] --rdfc:assumes--> [S6]
      C34:  [LAO] --rdfc:asserts--> [S7]
      C35:  [LAO] --rdfc:assumes--> [S8]
      C36:  [LAO] --rdfc:assumes--> [S9]
      C37:  [LAO] --rdfc:asserts--> [S10]


It should rather be two separate contexts:

      C31:  [LAO1] --rdf:type------> [rdfc:Context]
      C32:  [LAO1] --rdfc:assumes--> [S5]
      C33:  [LAO1] --rdfc:assumes--> [S6]
      C34:  [LAO1] --rdfc:asserts--> [S7]

      C35:  [LAO2] --rdf:type------> [rdfc:Context]
      C36:  [LAO2] --rdfc:assumes--> [S8]
      C37:  [LAO2] --rdfc:assumes--> [S9]
      C38:  [LAO2] --rdfc:asserts--> [S10]


But that usage doesn't seem to be consistent with the use of
rdfc:assuems for inclusion of subcontexts:

      C21:  [USL] --rdf:type------> [rdfc:Context]
      C22:  [USL] --rdfc:asserts--> [S1]
      C23:  [USL] --rdfc:asserts--> [S2]
      C24:  [USL] --rdfc:asserts--> [S4]
      C25:  [USL] --rdfc:assumes--> [LAO]

I think that it should use asserts also for subcontext inclusion:

      C21:  [USL] --rdf:type------> [rdfc:Context]
      C22:  [USL] --rdfc:asserts--> [S1]
      C23:  [USL] --rdfc:asserts--> [S2]
      C24:  [USL] --rdfc:asserts--> [S4]
      C25:  [USL] --rdfc:asserts--> [LAO]

And to make it complete:

      C39:  [LAO] --rdf:type------> [rdfc:Context]
      C40:  [LAO] --rdfc:asserts--> [LAO1]
      C41:  [LAO] --rdfc:asserts--> [LAO2]


And it's importent to note that an inference can't be done in a
context unless you have explicitly stated that you believe that the
inference rules are true.  That's what's done in C25.


If you say [Context1] --rdfc:assuems--> [Context2], that should be
interpreted as that we test the truth of Context2 to determine if the
assertions of Context1 is to be taken as true.



 [1] http://public.research.mimesweeper.com/RDF/RDFContexts.html

-- 
/ Jonas Liljegren

The Wraf project http://www.uxn.nu/wraf/
Sponsored by http://www.rit.se/
Received on Thursday, 23 November 2000 05:37:25 GMT

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