1,064 research outputs found
Multiple Conclusion Rules in Logics with the Disjunction Property
We prove that for the intermediate logics with the disjunction property any
basis of admissible rules can be reduced to a basis of admissible m-rules
(multiple-conclusion rules), and every basis of admissible m-rules can be
reduced to a basis of admissible rules. These results can be generalized to a
broad class of logics including positive logic and its extensions, Johansson
logic, normal extensions of S4, n-transitive logics and intuitionistic modal
logics
Dualized Simple Type Theory
We propose a new bi-intuitionistic type theory called Dualized Type Theory
(DTT). It is a simple type theory with perfect intuitionistic duality, and
corresponds to a single-sided polarized sequent calculus. We prove DTT strongly
normalizing, and prove type preservation. DTT is based on a new propositional
bi-intuitionistic logic called Dualized Intuitionistic Logic (DIL) that builds
on Pinto and Uustalu's logic L. DIL is a simplification of L by removing
several admissible inference rules while maintaining consistency and
completeness. Furthermore, DIL is defined using a dualized syntax by labeling
formulas and logical connectives with polarities thus reducing the number of
inference rules needed to define the logic. We give a direct proof of
consistency, but prove completeness by reduction to L.Comment: 47 pages, 10 figure
The Varieties of Ought-implies-Can and Deontic STIT Logic
STIT logic is a prominent framework for the analysis of multi-agent choice-making. In the available deontic extensions of STIT, the principle of Ought-implies-Can (OiC) fulfills a central role. However, in the philosophical literature a variety of alternative
OiC interpretations have been proposed and discussed. This paper provides a modular framework for deontic STIT that accounts for a multitude of OiC readings. In particular, we discuss, compare, and formalize ten such readings. We provide sound and complete sequent-style calculi for all of the various STIT logics accommodating these OiC principles. We formally analyze the resulting logics and discuss how the different OiC principles are logically related. In particular, we propose an endorsement principle describing which OiC readings logically commit one to other OiC readings
Structural completeness in propositional logics of dependence
In this paper we prove that three of the main propositional logics of
dependence (including propositional dependence logic and inquisitive logic),
none of which is structural, are structurally complete with respect to a class
of substitutions under which the logics are closed. We obtain an analogues
result with respect to stable substitutions, for the negative variants of some
well-known intermediate logics, which are intermediate theories that are
closely related to inquisitive logic
Multirole Logic (Extended Abstract)
We identify multirole logic as a new form of logic in which
conjunction/disjunction is interpreted as an ultrafilter on the power set of
some underlying set (of roles) and the notion of negation is generalized to
endomorphisms on this underlying set. We formalize both multirole logic (MRL)
and linear multirole logic (LMRL) as natural generalizations of classical logic
(CL) and classical linear logic (CLL), respectively, and also present a
filter-based interpretation for intuitionism in multirole logic. Among various
meta-properties established for MRL and LMRL, we obtain one named multiparty
cut-elimination stating that every cut involving one or more sequents (as a
generalization of a (binary) cut involving exactly two sequents) can be
eliminated, thus extending the celebrated result of cut-elimination by Gentzen
On Deriving Nested Calculi for Intuitionistic Logics from Semantic Systems
This paper shows how to derive nested calculi from labelled calculi for propositional intuitionistic logic and first-order intuitionistic logic with constant domains, thus connecting the general results for labelled calculi with the more refined formalism of nested sequents. The extraction of nested calculi from labelled calculi obtains via considerations pertaining to the elimination of structural rules in labelled derivations. Each aspect of the extraction process is motivated and detailed, showing that each nested calculus inherits favorable proof-theoretic properties from its associated labelled calculus
A simple sequent calculus for nominal logic
Nominal logic is a variant of first-order logic that provides support for
reasoning about bound names in abstract syntax. A key feature of nominal logic
is the new-quantifier, which quantifies over fresh names (names not appearing
in any values considered so far). Previous attempts have been made to develop
convenient rules for reasoning with the new-quantifier, but we argue that none
of these attempts is completely satisfactory.
In this article we develop a new sequent calculus for nominal logic in which
the rules for the new- quantifier are much simpler than in previous attempts.
We also prove several structural and metatheoretic properties, including
cut-elimination, consistency, and equivalence to Pitts' axiomatization of
nominal logic
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