Protesting too much: Self-deception and self-signaling

von Hippel and Trivers propose that self-deception has evolved to facilitate the deception of others. However, they ignore the subjective moral costs of deception and the crucial issue of credibility in self-deceptive speech. A self-signaling interpretation can account for the ritualistic quality of some self-deceptive affirmations, and for the often-noted gap between what self-deceivers say and what they truly believe.