Kripke Bundle Semantics and C-set Semantics

Kripke bundle 3] and C-set semantics 1] 2] are known as semantics which generalize standard Kripke semantics. In 3] and in 1], 2] it is shown that Kripke bundle and C-set semantics are stronger than standard Kripke semantics. Also it is true that C-set semantics for superintuitionistic logics is stronger than Kripke bundle semantics 5].In this paper, we show that Q-S4.1 is not Kripke bundle complete via C-set models. As a corollary we can give a simple proof showing that C-set semantics for modal logics are stronger than Kripke bundle semantics.