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arXiv · 2210.13953

First-order friendliness

Guillermo Badia·David Clement Makinson
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Abstract

In this note we study a counterpart in predicate logic of the notion of 'logical friendliness', introduced into propositional logic in Makinson (2007). The result is a new consequence relation for predicate languages using first-order models. Although compactness and interpolation fail dramatically, other properties are preserved from the propositional case.

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Guillermo Badia, David Clement Makinson. 2023-02-03. First-order friendliness. https://doi.org/10.1017/s175502032300014x

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