I'd like to look at deception, and especially self-deception, from a Darwinian perspective. When considering this domain through the lens of evolution, we will see that rather than fostering the most accurate perception of things, we are adapted to see things in a way that lends us some advantage. In fact, our evolutionary history has hardwired false belief systems that turn out to be an essential part of our makeup.
Nature has no love of truth. It's about winning, which is to say living to reproduce. Some orchids resemble female wasps and thereby attract males that pollinate the plant. Harmless snakes take on the coloring of poisonous ones gaining greater safety. There are literally millions of examples of species taking on superficial characteristics that allow them to be perceived as something they are not when it confers a survival advantage.
We are no different. The world is our stage, and yet there is a difference. While the innocuous snake who takes on the coloring of a poisonous one is under no illusions about its identity, we humans believe our P.R.
Social scientists have provided us with an abundance of data that beautifully illustrate this point. One experiment made use of the fact that when we hear our own voice, our galvanic skin response (GSR, a measure of changes in the conductivity of our skin) is greater than when we hear someone else's voice.
An unanticipated finding was that people, when asked if they hear their own voice, are right less often than their GSR. But the erroneous observations are not random. When subjects have been put through some exercise that lowers their self-esteem, they identify their voice as their own less frequently despite persistently accurate responses by GSR. And correspondingly when they are made to feel greater self-esteem, they claim ownership of not only their productions, but also the voices of others, despite an accurate GSR.
In other words, we may be capable of discerning external reality, but what gains consciousness is edited by some automatic function of which we have no awareness, that distorts our perceptions in predictable ways.
It's not exactly breaking news, but we consistently overrate things like our skill, generosity, and accomplishment. We perceive our victories as examples of our superiority and our defeats as demonstrations of bad luck. This has been documented with lie detectors, i.e. we believe these distortions and are lying to ourselves.,,
They call it the "better than average effect."
Most people judge themselves to be more intelligent, honest, original, friendly, and reliable than the average person. Drivers who have been hospitalized as a consequence of their poor driving, rate themselves as having better than average driving skills. My favorite example is that most people perceive themselves as less prone to such self-serving distortions than others.
So we fool ourselves. But to what end?
The brain's assignment is not to depict our environment in accurate detail. The brain's task, that brain that has been selected by a million years of evolution, is to create the greatest chances of reproducing. This often means increasing social status, or appearing more appealing to a potential mate, or more dangerous to an enemy. If this can be accomplished more readily with self-deception, so be it.
For example, it has been repeatedly proven that men over-perceive the sexual interest and intent of women. The Darwinian rational for such a distortion is that the cost of this misbelief is much less detrimental to reproductive success than it's opposite, that is the man's sense that the woman is uninterested. For women, not surprisingly, the cost asymmetry is reversed. For a woman to falsely believe in a man's interest in familial investment is more detrimental because it will result in abandonment and therefore a lower chance of the offspring's survival. If she were wrong in this biased perception of a man's familial investment, it would merely delay reproduction, a much less costly error. Let the mating dance begin.
Traditional psychological theories have considered a close relationship with truth as an essential ingredient of mental health. We're no longer so sure. In an amusing study, investigators assessed reality testing (how accurate one's observations are about oneself and the environment) in people on a spectrum of moods. The scale ran from clinically depressed, moderately depressed, normal mood, elevated mood, to manic. Surprisingly, the moderately depressed won the contest, providing the most "accurate" responses. The normal mood group consistently demonstrated unrealistically positive evaluations of themselves and their loved ones, exaggerated perceptions of personal control or mastery, and unrealistic optimism about the future.
These positive illusions are more accurately understood as design features of a normal mind rather than a brain function failure. In fact such positive misbeliefs are key to physical health as well. Unrealistically positive views about one's medical condition have been repeatedly linked to better outcomes than more accurate beliefs.
One might wonder how we are so good at fooling ourselves.
Because deceit is so fundamental in animal communication, there must be a strong selection to spot deception. This in turn led to a selection for self-deception, burying certain facts and motivations in the unconscious, so as to be the least obvious when our deception is being enacted. This protective failsafe-like system filters what we will allow ourselves to see.
We know our neighbor better than ourself.
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