RE: "Semantics" vs. "No Semantics"

There are three ways to define the semantics, two formal, one informal:
1) proof theory: axioms; this is typically harder than (2)
2) model theory
3) a natural language description describing the operational semantics.

Of course a 4th way is some combination of these.

What else is there?

Thanks,
Leo
  

-----Original Message-----
From: public-rif-wg-request@w3.org
[mailto:public-rif-wg-request@w3.org] On Behalf Of Peter F.
Patel-Schneider
Sent: Monday, May 08, 2006 6:12 PM
To: jos.deroo@agfa.com
Cc: public-rif-wg@w3.org
Subject: Re: "Semantics" vs. "No Semantics"


From: jos.deroo@agfa.com
Subject: Re: "Semantics" vs. "No Semantics"
Date: Mon, 8 May 2006 23:51:49 +0200

> 
> >I agree that there are many ways to approach semantics.  While I'm
not 
> >sure I would characterize model-theoretic semantics as more or less 
> >abstract than other approaches, I do fear that a model-theoretic 
> >semantics will be of little help
> >to the implementors of RIF translators and associated rule engines. 
> >Looking at other W3C formal semantic specifications for guidance, I
find 
> >http://www.w3.org/TR/xquery-semantics/ to be a good approach.
Formal 
> >XQuery semantics are specified using RULES.  Why can't we specify
RIF 
> >semantics using rules?  

How would that be different from a proof theory?

> We could even write those rules using RIF.

> I like that idea very much!

You mean using rules that we haven't given meaning to to give meaning
to
the rules?  I suspect that there are some potential pitfalls there.

> Looking for instance at pieces of
> http://www.w3.org/TR/rdf-mt/
> one sees a recurring pattern of
> Rule name  | If E contains | then add
> (and that is also how we implemented it).

Well this is in the entailment rules sections, which are (only)
informative. 

peter