A sequence of decidable finitely axiomatizable intermediate logics with the disjunction property
A sequence of decidable finitely axiomatizable intermediate logics with the disjunction property
复制标题
具有析取性质的可判定有限公理化中间逻辑序列
DOI:
10.2307/2272344
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发表时间:
1974
影响因子:
0.6
通讯作者:
D. D. Jongh
中科院分区:
文献类型:
--
作者:
D. Gabbay;D. D. Jongh
The intuitionistic propositional logic I has the following (disjunction) property . We are interested in extensions of the intuitionistic logic which are both decidable and have the disjunction property. Systems with the disjunction property are known, for example the Kreisel-Putnam system [1] which is I + (∼ϕ → (ψ ∨ α))→ ((∼ϕ→ψ) ∨ (∼ϕ→α)) and Scott's system I + ((∼ ∼ϕ→ϕ)→(ϕ ∨ ∼ϕ))→ (∼∼ϕ ∨ ∼ϕ). It was shown in [3c] that the first system has the finite-model property. In this note we shall construct a sequence of intermediate logics Dn with the following properties: These systems are presented both semantically and syntactically, using the remarkable correspondence between properties of partially ordered sets and axiom schemata of intuitionistic logic. This correspondence, apart from being interesting in itself (for giving geometric meaning to intuitionistic axioms), is also useful in giving independence proofs and obtaining proof theoretic results for intuitionistic systems (see for example, C. Smorynski, Thesis, University of Illinois, 1972, for independence and proof theoretic results in Heyting arithmetic).