Abstract: | In the present article, we prove the theorem which states that every table modal logic λ of depth 2 over S4 has a finite basis
of admissible inference rules. In addition, it is established that a finite algebra ℒ belongs to Fω(λ)Q iff there exist numbers n1…, nk such that
(Lemma 5). Let F be a λ-frame of depth 2 and b a cluster of the second layer in F. We show that for any n1,…,nk, there exist no p-morphisms from (Fn1⊔…⊔Fnk)+ a local component K (b) such that, for any n, there is no p-morphism from any local component of Fn onto K (b) (Lemma 6).
Translated fromAlgebra i Logika, Vol. 35, pp. 612–622, September–October, 1996. |