Results 231 to 240 of about 39,738 (264)

Omitting Types in an Intermediate Logic

Studia Logica, 2011
The authors prove an omitting-types theorem and one direction of the Ryll-Nardzewski theorem, from classical model theory, for a special intermediate logic, called semi-classical logic (SLC). The semi-classical logic is the logic of the class of linear constant-domain Kripke models with an extra constraint, i.e., every node of the model is identified ...
Bagheri, Seyed-Mohammad, Pourmahdian, Massoud   +1 more
openaire   +1 more source

On intermediate propositional logics

Journal of Symbolic Logic, 1959
By intermediate prepositional logics we mean prepositional logics between the intuitionistic and classical logics.K. Gödel [1] proved that there is a set of intermediate prepositional logics which possesses the order type ω. The method enables us to define intermediate logics in terms of axioms and rules of inference.
openaire   +1 more source

Three Intermediate Logics

1981
We saw in previous chapters the following properties of h: (1) h is complete for the class of all finite trees (2) h + is complete for the class of all finite n-ary trees, for any n≥2. (3) h is complete for the infinite full binary tree.
openaire   +1 more source

Proof analysis in intermediate logics

Archive for Mathematical Logic, 2011
The authors continue the investigation of cut-free systems for superintuitionistic logics inspired by translating a formula \(F\) into a formula saying ``\(F\) is true in all Kripke models'' (of a given logic). The approach works smoothly when the condition on the accessibility relation in Kripke models is expressed by a geometric formula \(\forall\bar{
Dyckhoff R., Negri S.
openaire   +1 more source

Frame Based Formulas for Intermediate Logics

Studia Logica, 2008
In the study of propositional logics, particularly of intermediate logics and normal modal logics, the so-called Jankov-de Jongh formulas defined by finite frames have been applied as a powerful tool to many important results in several topics such as axiomatizability, finite model property, splitting, construction of continuum many logics, and so on ...
openaire   +2 more sources

On finite approximability of ?-intermediate logics

Studia Logica, 1982
The aim of this note is to show (Theorem 1.6) that in each of the cases: ψ= {→, ∨ }, or {→, ∨, ∧ }, or {→, ∨, ℸ } there are uncountably many ψ-intermediate logics which are not finitely approximable. This result together with the results known in literature allow us to conclude (Theorem 2.2) that for each ψ: either all ψ-intermediate logics are ...
openaire   +2 more sources

Hypersequents, logical consequence and intermediate logics for concurrency

Annals of Mathematics and Artificial Intelligence, 1991
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire   +2 more sources

Intermediate predicate logic without the beth property

Algebra and Logic, 1998
Previously, the author has proven [Algebra Logika 35, No. 1, 105-117 (1996; Zbl 0897.03022)] that the interpolation property is missing in all predicate superintuitionistic logics which contain the logic \(J^*_{fd}\) (characterized by all Kripke frames whose domains of all nonmaximal worlds are finite) and are contained in a logic specified by all two ...
openaire   +2 more sources

Intermediate Logics

2000
Dov M. Gabbay, Nicola Olivetti
openaire   +1 more source

On Normalizing Disjunctive Intermediate Logics

2016
In this paper it is shown that every intermediate logic obtained from intuitionistic logic by adding a disjunction can be normalized. However, the normalization procedure is not as complete as that for intuitionistic and minimal logic because some results which usually follow from normalization fail, including the separation property and the subformula
openaire   +1 more source