Notre Dame Journal of Formal Logic

Generalizations of the Weak Law of the Excluded Middle

Andrea Sorbi and Sebastiaan A. Terwijn

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We study a class of formulas generalizing the weak law of the excluded middle and provide a characterization of these formulas in terms of Kripke frames and Brouwer algebras. We use these formulas to separate logics corresponding to factors of the Medvedev lattice.

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Notre Dame J. Formal Logic, Volume 56, Number 2 (2015), 321-331.

First available in Project Euclid: 17 April 2015

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 03B55: Intermediate logics 03G10: Lattices and related structures [See also 06Bxx]
Secondary: 03D30: Other degrees and reducibilities

weak law of the excluded middle Brouwer algebras Medvedev degrees


Sorbi, Andrea; Terwijn, Sebastiaan A. Generalizations of the Weak Law of the Excluded Middle. Notre Dame J. Formal Logic 56 (2015), no. 2, 321--331. doi:10.1215/00294527-2864325.

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