Results 11 to 20 of about 86 (68)

Minimal models of Heyting arithmetic [PDF]

open access: yesJournal of Symbolic Logic, 1997
In this paper, we give a constructive nonstandard model of intuitionistic arithmetic (Heyting arithmetic). We present two axiomatisations of the model: one finitary and one infinitary variant. Using the model these axiomatisations are proven to be conservative over ordinary intuitionistic arithmetic. The definition of the model along with the proofs of
Moerdijk, I., Palmgren, E.
openaire   +2 more sources

Propositional Logics of Closed and Open Substitutions over Heyting's Arithmetic [PDF]

open access: yesNotre Dame Journal of Formal Logic, 2006
In this note we compare propositional logics for closed substitutions and propositional logics for open substitutions in constructive arithmetical theories. We provide a strong example where these logics diverge in an essential way. We prove that for Markov's Arithmetic, that is, Heyting's Arithmetic plus Markov's principle plus Extended Church's ...
openaire   +5 more sources

Interactive Realizability for second-order Heyting arithmetic with EM1 and SK1 [PDF]

open access: yesMathematical Structures in Computer Science, 2013
We introduce a realizability semantics based on interactive learning for full second-order Heyting arithmetic with excluded middle and Skolem axioms over Σ10-formulas. Realizers are written in a classical version of Girard's System$\mathsf{F}$and can be viewed as programs that learn by interacting with the environment. We show that the realizers of any
openaire   +3 more sources

Mathematical pluralism

open access: yesNoûs, Volume 58, Issue 2, Page 306-332, June 2024.
Abstract Mathematical pluralism can take one of three forms: (1) every consistent mathematical theory consists of truths about its own domain of individuals and relations; (2) every mathematical theory, consistent or inconsistent, consists of truths about its own (possibly uninteresting) domain of individuals and relations; and (3) the principal ...
Edward N. Zalta
wiley   +1 more source

Weyl and two kinds of potential domains

open access: yesNoûs, Volume 58, Issue 2, Page 409-430, June 2024.
Abstract According to Weyl, “‘inexhaustibility’ is essential to the infinite”. However, he distinguishes two kinds of inexhaustible, or merely potential, domains: those that are “extensionally determinate” and those that are not. This article clarifies Weyl's distinction and explains its enduring logical and philosophical significance.
Laura Crosilla, Øystein Linnebo
wiley   +1 more source

On the completenes principle: A study of provability in heyting's arithmetic and extensions

open access: yesAnnals of Mathematical Logic, 1982
AbstractIn this paper extensions of HA are studied that prove their own completeness, i.e. they prove A → □ A, where □ is interpreted as provability in the theory itself. Motivation is three-fold: (1) these theories are thought to have some intrinsic interest, (2) they are a tool for producing and studying provability principles, (3) they can be used ...
openaire   +3 more sources

Modern perspectives in Proof Theory. [PDF]

open access: yesPhilos Trans A Math Phys Eng Sci, 2023
Aguilera JP, Pakhomov F, Weiermann A.
europepmc   +1 more source

Intuitionistic fixed point theories over Heyting arithmetic

open access: yes, 2010
In this paper we show that an intuitionistic theory for fixed points is conservative over the Heyting arithmetic with respect to a certain class of formulas. This extends partly the result of mine. The proof is inspired by the quick cut-elimination due to G. Mints.
openaire   +2 more sources

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