@TECHREPORT{Schmidt97c,
AUTHOR = {Schmidt, R. A.},
MONTH = {January},
YEAR = {1997},
TITLE = {Resolution is a Decision Procedure for Many Propositional Modal Logics},
TYPE = {Technical Report},
NUMBER = {MPI-I-97-2-002},
INSTITUTION = {Max-Planck-Institut f{\"u}r Informatik},
ADDRESS = {Saarbr{\"u}cken, Germany},
NOTE = {Submitted for publication in \emph{J.\ Automat.\ Reasoning}.
The extended abstract version is to appear in Kracht, M., de Rijke, M.,
Wansing, H.  and Zakharyaschev, M. (eds) (1997), \emph{Advances in Modal Logic
`96}, CSLI Publications.},
ABSTRACT = {%
The paper shows satisfiability in many propositional modal systems can
be decided by ordinary resolution procedures.
This follows from a general result that resolution and condensing is a
decision procedure for the satisfiability problem of formulae in
so-called \emph{path logics}.
Path logics arise from propositional and normal uni- and multi-modal
logics by the \emph{optimised functional translation} method.
The decision result provides an alternative decision proof for the
relevant modal logics (including \textit{K}, \textit{KD}, \textit{KT}
and \textit{KB}, their combinations as well as their multi-modal
versions), and related systems in artificial intelligence.
This alone is not interesting.
A more far-reaching consequence of the result has practical value,
namely, any standard first-order theorem prover that is based on
resolution can serve as a reasonable and efficient inference tool for
modal reasoning.
}}

