Per Se Modality and Natural Implication – an Account of Connexive Logic in Robert Kilwardby

Spencer Johnston



We present a formal reconstruction of the theories of the medieval logician Robert Kilwardby, focusing on his account of accidental and natural inferences and the underlying modal logic that gives rise to it. We show how Kilwardby’s use of an essentialist modality underpins his connexive account of implication.


Robert Kilwardby; connexive logic; modal logic; medieval logic

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ISSN: 1425-3305 (print version)

ISSN: 2300-9802 (electronic version)

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