Re: Contexts and quantifiers in KIF

Jim Fulton <>
Date: Fri, 9 Apr 93 09:08:59 -0700
From: Jim Fulton <>
Message-id: <>
To:, interlingua@ISI.EDU,,
Subject: Re:  Contexts and quantifiers in KIF

I just received your reply to Pat Hayes and myself.  A lot of it needs digestion
but I do want to respond to one point, namely your treatment of modal logic:

The SITUATION construct you discussed adding to your TARGET language, not your 
METALANGUAGE, is a MODAL construct.  It is formally intensional in that it (or 
constructs like it) resist quantification across the construct and they resist 
replacement of identicals or equivalences.  Moreover, if the word 'situation' 
is taken literally, it appears so similar in meaning to Kripkean "possible 
worlds" that the differences appear to be quibbles.  

Secondly, the fact that Tarski restricted the scope of his original paper to 
formalized languages is not particularly telling in this context.  The purpose 
of his paper was to demonstrate an approach to semantics, and he succeeded 
for a broad class of formal languages.  What he did not do in that paper was 
demonstrate that the same approach could be applied to natural languages.  
But he also did not say that the approach could not be applied to natural 
languages.  Indeed applied logicians and philosophers have applied the 
approach successfully to significant subsets of natural language.  The work 
we have done on the SUMM shows that the approach works for that subset of 
natural language that is captured in information systems of the kind that 
can be captured by EXPRESS, NIAM, ER, etc.  So the issue is not whether the 
information is initially expressed in a formalized language, but the 
communicants can agree that a formalization captures the essence of what 
they are communicating with sufficient accuracy.