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    ELECTRONIC NEWSLETTER ON  REASONING ABOUT ACTIONS AND CHANGE        
Issue 97027             Editor: Erik Sandewall            25.11.1997
Back issues available at http://www.ida.liu.se/ext/etai/actions/njl/
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                    *********  TODAY  *********

IMPORTANT MESSAGE if you are submitting an article to KR-98
or to ECAI-98: the program chairs of these two conferences
confirm that it is perfectly compatible with their paper
submission procedures to have articles under review 
(= discussion) in the ETAI while they are being considered for
the conference. In other words, as soon as you send the paper
to the conference, feel free to enter it for discussion in our
Newsletter.

Formally, the rules work as follows. In the ETAI, you first have 
the article discussed for three months, then you have a chance to
revise it based on the feedback, and *then you decide whether
to submit it for refereeing in the ETAI* or in some other journal.
Therefore, as long as you don't proceed into the refereeing step
before you get the decision from the KR or ECAI, they do not 
mind. It's considered analogous to participation in a workshop.

Doing this gives you the advantage of maximum visibility for the
paper at the earliest possible stage. Admittedly, there is a
risk that if you get heavily criticized in the Newsletter, it 
might damage your chances in the conference refereeing. But on
the other hand, in the Newsletter you have a chance to respond
immediately to the critique if it is not well founded; if you
only rely on the conference reviewing then you do not have any
chance of dialogue. Therefore, if you feel your paper is a quite
good one, you can only gain by sending it to the ETAI. Email me
if you want to find out how to go about this.


                   *********  DEBATES  *********

---  NRAC PANEL DISCUSSION ON ONTOLOGIES FOR ACTIONS AND CHANGE  ---

--------------------------------------------------------
|  FROM: Pat Hayes
--------------------------------------------------------

Vladimir Lifschitz writes:
>
> It seems to me that the semantics of an action language cannot be
> described by specifying truth conditions for its propositions.  The
> problem is the same as with nonmonotonic languages in general.  Take,
> for instance, the closed-world database {P(1),P(2)}.  The negation of
> P(3) is a consequence of this database, but this fact cannot be
> justified on the basis of truth conditions for P(1) and P(2).
>

But it can be justified on the basis of the truth conditions for P(3),
which is just as much a proposition of the language as the first two.
Nonmonotonic logics are not classically truthfunctional,  but they do have
truth conditions. The simple language sketched here has the truth
condition: P(n) is true iff P(n) occurs in the database.

Pat Hayes


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