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arXiv · 1311.2010

Natural Factors of the Medvedev Lattice Capturing IPC

Rutger Kuyper
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Abstract

Skvortsova showed that there is a factor of the Medvedev lattice which captures intuitionistic propositional logic (IPC). However, her factor is unnatural in the sense that it is constructed in an ad hoc manner. We present a more natural example of such a factor. We also show that for every non-trivial factor of the Medvedev lattice its theory is contained in Jankov's logic, the deductive closure of IPC plus the weak law of the excluded middle. This answers a question by Sorbi and Terwijn.

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Rutger Kuyper. 2013-11-08. Natural Factors of the Medvedev Lattice Capturing IPC. https://doi.org/10.1007/s00153-014-0393-8

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