Many thanks, Chris. See below ... (01)
Christopher Menzel wrote:
> On Sep 12, 2008, at 8:44 PM, Rick Murphy wrote:
>> Chris & All:
>>
>> Glad to see model theory come up again. I have a keen interest in
>> better
>> understanding how model theory differentiates meaning from truth.
>
> This is of course a very controverial issue, one whose relevance to KR
> is not at all clear, as the whole notion of a theory of meaning
> typically has to do with natural language, not the sorts of formal
> languages we find in KR. (02)
Understood. My intent in writing the semantic web post was to heighten
awareness in W3C about its relevance. There's much work to be done
there, but I suspect you, Pat and others here recognize its relevance. (03)
> That said, one can certainly say that a
> theory of meaning for a formal language just *is* a formal semantics. (04)
Sure, but here the copula implies a paradigm shift in formal semantics
beyond Tarski's material adequacy and formal correctness. (05)
> But whether we do or we don't, it's just a quibble about how to use
> the expression "theory of meaning". (06)
Maybe I have too much time on my hands, but I think there's much more
than a quibble here. I understand the expression "theory of meaning" has
come to be used as a colloquialism and I believe that should change. (07)
> The point is, the issue of
> meaning for natural languages seems to me to have little bearing on
> the claim that a usable KR language must have a formal semantics. (08)
Agreed. (09)
>> My current understanding is that Tarski claims to provide a semantic
>> conception of truth in his paper of the same name where truth is
>> defined
>> in terms of material adequacy and formal correctness. He does not
>> claim
>> to provide a theory of meaning ...
>
> Yes, that is well known. Indeed, Tarski didn't really seem to be
> interested in the theory of meaning for natural languages at all.
> Indeed, one of his motivations for developing his theory of truth for
> formal languages is that he found natural languages fraught with
> ambiguity and inconsistency. (010)
Understood. So, when Tim BL says web of meaning, he means web of truth. (011)
>> I also understand that when Pat Hayes wrote the RDF semantics
>> document for W3C, he chose to exclude a theory of meaning from the
>> scope of the document.
>
> This is either obviously true or obviously false. (012)
It's true. The scope and limitations section reads in part as follows: (013)
"Exactly what is considered to be the 'meaning' of an assertion in RDF
or RDFS in some broad sense may depend on many factors, including social
conventions, comments in natural language or links to other
content-bearing documents. Much of this meaning will be inaccessible to
machine processing and is mentioned here only to emphasize that the
formal semantics described in this document is not intended to provide a
full analysis of 'meaning' in this broad sense; that would be a large
research topic. The semantics given here restricts itself to a formal
notion of meaning which could be characterized as the part that is
common to all other accounts of meaning, and can be captured in
mechanical inference rules." (014)
> RDF is a formal
> language. So if we include such languages in the scope of "theory of
> meaning", he provided a theory of meaning for RDF via his semantics.
> If we don't, then the notion simply has no relevance to what Pat was
> doing. (015)
Fair statement if we use "theory of meaning" as a colloquialism
referencing Tarski model theory. (016)
>> I am also especially interested in some decisions made by Tim BL &
>> Co in the linked data activity that relate to material adequacy. My
>> current understanding is that non-information resources gets a 303,
>> then a redirect to another uri which is a representation of the non-
>> information resource that can be later rendered by a browser.
>>
>> These decisions seem to imply the need to revise the existing RDF
>> model
>> theory with regards to material adequacy in that information and
>> non-information resources are now specified. My intuition is that the
>> issue here is more with material adequacy as interpretation than
>> possible worlds.
>
> Sorry, I'm not really following you here. (017)
W3C has a new design initiative called linked data. (018)
http://www.w3.org/DesignIssues/LinkedData.html (019)
Differentiating non-information resources from information resources
affects material adequacy in RDF model theory in this way:
non-information resources are supposito materialis and information
resources are supposito formalis. Interpreting an RDF vocabulary needs
to acknowledge this change. (020)
>> I need to get back to Soames's refutation of the Davidsonian program
>> which attempted to derive a theory of meaning from Tarski's semantic
>> conception of truth. I had previously referenced this paper ...
>>
>> http://www-rcf.usc.edu/~soames/forthcoming_papers/
>> Truth_and_Meaning.pdf
>>
>> and wondered whether anyone was interested in sharing their thoughts ?
>
> This is a very interesting philosophical issue which, in my view, is
> pretty much irrelevant to the thesis that any KR language worth its
> salt needs a formal semantics. (021)
True. We just need a new formal semantics. Otherwise we'll have a whole
lot of folks calling the web of truth, the web of meaning. And naieve
folks like me are naturally lead to believe that when folks use the word
semantics, they're talking about meaning, not truth. (022)
> -chris
>
>
>
>
> _________________________________________________________________
> Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
> Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
> Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
> Shared Files: http://ontolog.cim3.net/file/
> Community Wiki: http://ontolog.cim3.net/wiki/
> To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx
>
>
> (023)
_________________________________________________________________
Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/
Subscribe/Config: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx (024)
|