Because I Believe It, I Ain't Lying
It's not a life if you believe it
People sometimes self-deceive. They convince themselves that they are in better physical shape than they are, tell themselves they are more successful and popular than they actually are, and so on. People lie to themselves. We know that. The real puzzle, then, is why people would engage in self-deception. The obvious first answer is that people engage in self-deception to feel better about themselves—if people can convinced themselves they are funnier, smart, better looking, and more popular than they actually are, they will likely feel better about themselves.
The puzzle with such a practice, though, is that self-deception, like any variety of deception, has costs. To the extent that the truth allows us to navigate the world, form relationships with others, and etc., it is puzzling that people would engage in self-deception except, perhaps, as a product of irrationality. And from an evolutionary perspective, self-deception makes even less rational sense: to engage in self-deception is to risk depriving oneself of information that may be needed to avoid death, or needed to find a mate, food, and shelter. If I attempt to take on a hungry tiger, and I am self-deceived—thinking I am better with a spear than I actually am—I could be seriously injured or killed. By contrast, if I recognize I am terrible with a spear, I may choose to retreat instead of engaging with a large carnivorous cat.
As the philosopher, Patricia Churchland, explains about evolution,
Looked at from an evolutionary point of view, the principal function of nervous systems is to enable the organism to move appropriately. Boiled down to the essentials, a nervous system enables the organism to succeed in the four F’s: feeding, fleeing, fighting, and reproducing. The principal chore of nervous systems is to get the body parts where they should be in order that the organism may survive […] Getting things right in space and time, therefore, is a crucially important factor for nervous systems […]1
So, it would appear, at first glance, that evolution wouldn’t favor self-deception. And yet, it appears from the ubiquity of self-deception across the human species that there are, perhaps, benefits to self-deception that aren’t immediately obvious. To start making this case, we should first consider that humans are equipped with excellent social cognition and a theory of mind that consists ‘in the ability to use concepts of intentional mental states, such as beliefs, emotions, intentions, goals, and perceptual states, in order to predict and interpret behavior2.’ Here’s an example: I can say with certainty that former President Barack Obama doesn’t believe that the moon is made of green cheese.
As it happens, though, self-deception has an indirect benefit: it makes us better liars. How? Consider that from a psychological point of view, the act of cheating triggers stress and anxiety in all of us. No one likes to cheat and lie. And it’s also cognitively difficult maintaining two contradictory beliefs at once—the truth and the lie. As a result of the stress deception causes, we often give off involuntary clues to others that we are being deceptive3. However, self-deception helps us reduce the internal anxiety and cognitive burden felt when we lie, self-deception can trigger the misremembering or even forgetting of certain events. If we are convinced we’re telling the truth—even though we are unconsciously engaged in self-deception—then we won’t have external cues that can reveal our deception. As the evolutionary biologist, Robert Trivers, explains:
If […] deceit is fundamental in animal communication, then there must be strong selection to spot deception and this ought, in turn, select for a degree of self-deception, rendering some facts and motives unconscious so as to not betray—by the subtle signs of self-knowledge—the deception being practiced … [The] conventional view that natural selection favors nervous systems which produce ever more accurate images of the world must be a very naïve view of mental evolution4.
And elsewhere,
The central proposal of our evolutionary approach to self-deception is that by deceiving themselves, people can better deceive others, because they no longer emit the cues of consciously mediated deception that could reveal their deceptive intent5.
We self-deceive to better deceive others, or to better deceive polygraph devices. This is illustrated nicely in a scene from Seinfeld,
Jerry: So, George, how do I beat this lie detector?
George: I'm sorry, Jerry, I can't help you.
Jerry: Come on, you've got the gift. You're the only one that can help me.
George: Jerry, I can't. It's like saying to Pavarotti, "Teach me to sing like you."
Jerry: All right, well I've got to go take this test. I can't believe I'm doing this.
George: Jerry, just remember. It's not a lie if you believe it.
(From Season 6, Episode 16, ‘The Beard’).
Perhaps George Costanza and Robert Trivers have a point.
Patricia Churchland (1987). Epistemology in the Age of Neuroscience. The Journal of Philosophy 84 (10): 544-553, p. 548-49.
Westra, Evan and Peter Carruthers (2017). Theory of Mind. In: Shackelford T., Weekes-Shackelford V. (eds.) Encyclopedia of Evolutionary Psychological Science. Springer.
DePaulo, B. M., Lindsay, J. J., Malone, B. E., Muhlenbruck, L., Charlton, K. & Cooper, H. (2003). Cues to Deception. Psychological Bulletin, 129 (1): 74-118.
Robert Trivers (2006). Forward. Richard Dawkins, The Selfish Gene (3rd Edition). Oxford University Press, pp. 19-20 (emphasis mine).
William von Hippel and Robert Trivers (2011). The Evolution and Psychology of Self-Deception. Behavioral and Brian Science 34 (1): 1-16 (emphasis mine).