Products of ‘transitive’ modal logics without the (abstract) finite model property
نویسنده
چکیده
It is well known that many two-dimensional products of modal logics with at least one ‘transitive’ (but not ‘symmetric’) component lack the product finite model property. Here we show that products of two ‘transitive’ logics (such as, e.g., K4 ×K4, S4 × S4, Grz×Grz and GL×GL) do not have the (abstract) finite model property either. These are the first known examples of 2D modal product logics without the finite model property where both components are natural unimodal logics having the finite model property.
منابع مشابه
Products of ‘ transitive ’ modal logics . Part I : ‘ negative ’ results Draft
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