Animal deception and the content of signals

In cases of animal mimicry, the receiver of the signal learns the truth that he is either dealing with the real thing or with a mimic. Thus, despite being a prototypical example of animal deception, mimicry does not seem to qualify as deception on the traditional definition, since the receiver is not actually misled. We offer a new account of propositional content in sender-receiver games that explains how the receiver is misled (and deceived) by mimicry. We show that previous accounts of deception, and of propositional content, give incorrect results about whether certain signals are deceptive. •Surprisingly, signals sent by animal mimics are not actually misleading.•Animal mimicry is not deceptive on the traditional definition of deception.•Many existing definitions of deception misclassify withholding info as deception.•Existing accounts of propositional content misclassify withholding info as deception.•Propositional content is determined by which signalers are okay with honesty.