In many cases, inconsistent fuzzy control rules can be obtained when t
he information about the controlled plant is uncertain and/or the syst
em is very complex. In most cases, inconsistent rules have been consid
ered as ill-defined rules and, thus, not allowed to be in the same rul
e base. One way to handle the situation is to try to extract core info
rmation from the whole set containing the inconsistent rules. This app
roach can be useful especially when it is difficult to separate consis
tent rules from the set of inconsistent rules. In the paper, an infere
nce scheme is presented to extract core information from such a rule b
ase with inconsistent rules. The proposed inference scheme with the ai
d of a statistical concept justifies application of all the rules with
inconsistent rules in the same rule base for effective control of a c
omplicated plant. A simulation study is performed for a truck-and-trai
ler backer-upper control. The result shows that inconsistent rules can
be effectively utilized if a proper inference method is adopted for t
he extracted rules.