The Many Faces of Deception

Chiaki Sakama and Martin Caminada

Proceedings of the Thirty Years of Nonmonotonic Reasoning (NonMon@30), Lexington, KY, USA, October 2010.


This paper formalises various forms of deception, that were originally described in an informal way by Chisholm and Feehan (1977). To this end, we use a modal logic of action and belief developed by Porn et al. We provide logical definitions of deception by commission and deception by omission, and investigate their formal properties. We also study intended deception and discuss its relationship with lying. According to our formulation, deception is captured as a form of reasoning about causation that is inherently nonmonotonic in its nature.

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