Deception in Epistemic Causal Logic

Chiaki Sakama

DeceptiveAI, Communications in Computer and Information Science, volume 1296, pages 105-123, Springer, 2021.


Deception is an act whereby one person causes another person to have a false belief. This paper formulates deception using causal relations between a speaker's utterance and a hearer's belief states in epistemic causal logic. Four different types of deception are considered: deception by lying, deception by bluffing, deception by truthful telling, and deception by omission, depending on whether a speaker believes what he/she says or not, and whether a speaker makes an utterance or not. Next several situations are considered where an act of deceiving happens. Intentional deception is accompanied by a speaker's intent to deceive. Indirect deception happens when false information is carried over from person to person. Self-deception is an act of deceiving the self. The current study formally characterizes various aspects of deception that have been informally argued in philosophical literature.

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