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O IS NOT ENOUGH

Published online by Cambridge University Press:  09 July 2009

J. B. PARIS*
Affiliation:
School of Mathematics, University of Manchester
R. SIMMONDS*
Affiliation:
School of Mathematics, University of Manchester
*
*SCHOOL OF MATHEMATICS, UNIVERSITY OF MANCHESTER, MANCHESTER M13 9PL, UK. E-mail:jeff.paris@manchester.ac.uk
SCHOOL OF MATHEMATICS, UNIVERSITY OF MANCHESTER, MANCHESTER M13 9PL, UK. E-mail:richard.simmonds@gmail.com

Abstract

We examine the closure conditions of the probabilistic consequence relation of Hawthorne and Makinson, specifically the outstanding question of completeness in terms of Horn rules, of their proposed (finite) set of rules O. We show that on the contrary no such finite set of Horn rules exists, though we are able to specify an infinite set which is complete.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2009

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References

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