Deception gains a slight edge over deception detection when the interactions are few in number and among strangers. But if you spend enough time with your interlocutors, they may leak their true intent through behavioral tells. As Trivers notes, “When interactions are anonymous or infrequent, behavioral cues cannot be read against a background of known behavior, so more general attributes of lying must be used.” He identifies three: Nervousness. “Because of the negative consequences of being detected, including being aggressed against … people are expected to be more nervous when lying.” Control. “In response to concern over appearing nervous … people may exert control, trying to suppress behavior, with possible detectable side effects such as … a planned and rehearsed impression.” Cognitive load. “Lying can be cognitively demanding. You must suppress the truth and construct a falsehood that is plausible on its face and … you must tell it in a convincing way and you must remember the story.”
Cognitive load appears to play the biggest role. “Absent well-rehearsed lies, people who are lying have to think too hard, and this causes several effects,” including overcontrol that leads to blinking and fidgeting less and using fewer hand gestures, longer pauses and higher-pitched voices. As Abraham Lincoln well advised, “You can fool some of the people all of the time and all of the people some of the time, but you cannot fool all of the people all of the time.” Unless self-deception is involved. If you believe the lie, you are less likely to give off the normal cues of lying that others might perceive: deception and deception detection create self-deception.
By employing the logic of deception and self-deception, we can build a bottom-up theory for the evolution of emotions that control behavior judged good or evil by our fellow primates. In this understanding lies the foundation of a secular civil society.
