منابع مشابه
Defining Double Negation Elimination
In his paper “Generalised Ortho Negation” [2] J. Michael Dunn mentions a claim of mine to the effect that there is no condition on ‘perp frames’ equivalent to the holding of double negation elimination ∼∼A ` A. That claim is wrong. In this paper I correct my error and analyse the behaviour of conditions on frames for negations which verify a number of different theses.1 1 Compatibility Frames D...
متن کاملDouble-Negation Elimination in Some Propositional Logics
This article answers two questions (posed in the literature), each concerning the guaranteed existence of proofs free of double negation. A proof is free of double negation if none of its deduced steps contains a term of the form n(n(t)) for some term t, where n denotes negation. The first question asks for conditions on the hypotheses that, if satisfied, guarantee the existence of a double-neg...
متن کاملA Type-Directed Negation Elimination
In the modal μ-calculus, a formula is well-formed if each recursive variable occurs underneath an even number of negations. By means of De Morgan’s laws, it is easy to transform any well-formed formula φ into an equivalent formula without negations – the negation normal form of φ . Moreover, if φ is of size n, the negation normal form of φ is of the same size O(n). The full modal μ-calculus and...
متن کاملNegation and Double-Negation of Chinese Oppositeness
Oppositeness refers to the paradigmatic relationship of two words holding the contrast meanings. The fact that linguistic opposite differs from logical contrast has been discussed in theories, but has not been tested in practice. In this paper, we investigate three main subtypes of Chinese oppositeness, via using logical tests of negation and double-negation. Result shows that purely logical te...
متن کاملUltrasheaves and Double Negation
Moerdijk has introduced a topos of sheaves on a category of lters. Following his suggestion, we prove that its double negation subtopos is the topos of sheaves on the subcategory of ultra lters the ultrasheaves. We then use this result to establish a double negation translation of results between the topos of ultrasheaves and the topos on lters. 2000 Mathematics Subject Classi cation. Primary 0...
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ژورنال
عنوان ژورنال: Logic Journal of IGPL
سال: 2000
ISSN: 1367-0751,1368-9894
DOI: 10.1093/jigpal/8.6.853