Comments: I did not know how to enter the keywords,  
so I separated them with commas, even the phrases. 
If they should be in quotes, please fix (I didn't 
think that each word should stand alone.   
There may also seem to be duplicates, since I don't 
know how well the search system works (e.g. if searcher 
enters "beliefs", will "belief" get a hit?)
ContactPerson: flj@cse.buffalo.edu
Remote host: mira.cse.buffalo.edu
Remote ident: flj
### Begin Citation ### Do not delete this line ###
%R 2000-02
%U /projects/flj/tech-reports/CSE-tech-reports/DOBS.ps
%A Johnson, Frances L.
%A Shapiro, Stuart C.
%T Formalizing a Deductively Open Belief Space
%D January 24, 2000
%I Department of Computer Science and Engineering, SUNY Buffalo
%K knowledge; belief; belief space; knowledge representation; belief revision; belief change; beliefs
%Y Knowledge Representation Formalisms and Methods
%X A knowledge representation and reasoning system must be able to  
deal with contradictions and revise beliefs.  There has been much  
research in belief revision in the last decade, but this research  
tends to be either in the Coherence camp (AGM) or the Foundations  
(TMS) camp with little crossover.  Most theoretical postulates on  
belief revision and belief contraction assume a deductively closed  
belief space - something that is computationally hard (or  
impossible) to produce in an implementation.  This makes it  
difficult to analyze implemented belief revision systems using the  
theoretical postulates.  This paper offers a formalism that  
describes a deductively open belief space (DOBS).  It then uses  
this formalism to alter the AGM integrity constraints for a DOBS.   
 A DOBS uses a base set of hypotheses, but only deduces beliefs  
from that base as the result of specific queries. Thus, it can  
grow over time even if the base remains static, and can never be  
referred to as consistent - only either inconsistent or "not known  
to be inconsistent." This work and future alterations to the  
traditional postulate formalisms will better enable  
system/postulate comparisons.