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Re: rdf as a base for other languages

From: Sandro Hawke <sandro@w3.org>
Date: Fri, 01 Jun 2001 14:07:50 -0500
Message-Id: <200106011808.OAA24374@tux.w3.org>
To: "Jonathan Borden" <jborden@mediaone.net>, www-rdf-logic@w3.org
In message <06c801c0eab9$dcada230$0a2e249b@nemc.org> you wrote:
>Sandro Hawke wrote:
>> The only potential for confusion I see is that some people might want
>> to jump from having a triple described (with ground facts) to assuming
>> the described triple is true, but that seems clearly wrong.
>
>Calling something a "fact" implies that it is "true". You might try to
>assert a falsehood but that would be false or inconsistent. To be consistent
>you must assert a fact, i.e. the fact _must be_ true. What am I clearly
>missing?

I don't understand where we're not understanding each other.

For example, here are 7 facts:
  1.  I can imagine a condition, X.
  2.  X can be expressed accurately as English sentence Y.
  3.  Y has four words.
  4.  The first word of Y is "the".
  5.  The second word of Y is "sun".
  6.  The third word of Y is "is".
  7.  The fourth word of Y is "shining".

Now I'm not exactly sure which of X and Y might be best called a
"condition", "state", "statement", "declartion", "sentence",
"situation", etc, etc. but using only true ground facts I have
essentially communicated X and Y to you without asserting them.

If you take everything I say as true and I add an 8th fact: "X is
true" or "X is a fact" then you are licensed to infer that the sun is
shining.

If instead I add an 8th fact: "X is not true" then I have made no
contradiction; I have actually made a reasonable and useful statement,
licensing you to infer that the sun is, in fact, not shining.

Do you have any problem with this approach, beyond style?   

I'm sorry I haven't looked at your strawman yet, but I think it has
a somewhat different syntax for facts like:

   1.  Statement 1 is an asserted statement that I can imagine a
       condition, X. 
   2.  Statement 2 is an asserted statement that X can be expressed
       accurately as English sentence fact 3.
   3.  Statement 3 is an UNASSERTED statement that the sun is shining.

The differences between these approaches seem trivial.  Any formal
language using the first approach can be machine translated to & from
any formal language using the second approach, given a vocabulary for
(1) describing the parts of a sentence and (2) asserting sentences.

   -- sandro
Received on Friday, 1 June 2001 14:08:01 GMT

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