The Psychology of Deception

Why humans lie about everything

If you’re a human, then I don’t need to tell you that people lie all the time. It’s built into the framework of our social lives. Just try to get through a day without telling a single lie. Go ahead. It’s damn near impossible. And if you tell me you did—well I know you’re lying.

The question is, why do humans lie about everything? First, let’s define what we mean by lying.

What is deception?

• Deception is an active misrepresentation of reality to another conscious mind (Trivers, 2013).
• Deception involves deliberately misleading a person to believe something that is untrue or by concealing true information (Whiten & Byrne, 2002).
• Deception is largely accepted as a widespread feature of communication, although the extent to which it is intentional is debated (Vrij & Granhag, 2012).

Lying is a cognitive ability that evolved primarily for social reasons. As humans, our primary vehicle for social interaction is language. The more complex a communication system is, the more likely it is that the system will be used to misrepresent the truth, both intentionally and unintentionally.

Language is like a bag of tricks for our species, and lying is one of our most useful tricks. So, what do we get out of it?

Why do people lie?

• To obtain more resources from others
• To maintain alliances and manage social relationships
• To secure mating partners (see Johnson et al., 2004)
• To appear better, smarter, more attractive (see Feldman et al., 2002)
• To facilitate conversations and make others feel better

When you break down the reasons, it almost makes more sense to ask why anyone wouldn’t lie. But if we really think about it, there can be pretty serious costs to deception as well.

The price of deception

• Social consequences: you could lose your friends
• Legal consequences: lying under oath, slander, fraud, etc.
• Moral consequences: in many belief structures, lying is considered a moral transgression
• Practical consequences: lying is cognitively difficult, stressful, annoying, and generally takes skill and a good memory
• Psychological consequences: distorting reality can lead to self-deception and denial

When you put it all in context, this whole endeavor of lying is not as easy as it seems. In fact, lying requires a big brain. Many scientists have argued that deception ability is positively correllated with neocortical volume (Ganis, 2003).

It runs deep in our ancestry and many biologists believe it has its roots the near-universal predator-prey dynamic that exists throughout the animal kingdom (Stevens, 2016). Some basic forms of deception seen in other species include disguise, mimicry, camouflage, distraction, and diversion.

Speaking of development and brains—you might be wondering when exactly do humans start lying?

Development of deception in children

• Humans are able to deceive as early as 3 years of age (Chandler et al., 1989).
• Sophisticated deception ability increases as children get older and they become exposed to more complex social relationships.
• Deception hinges on other aspects of social cognition, such as self-awareness and theory of mind, both of which are required for a child to understand other minds. These abilities emerge in children around 2 years of age.

If you have a child, you know they sometimes lie to avoid getting in trouble. Early on, it’s natural for humans to tell lies that are self-serving. But not all lies are created equal.

Types of lies

• Self-centered lies are lies told to protect or enhance the liar’s interest.
• Other-oriented lies (or pro-social lies) are told to protect or enhance the interest of others.
• Outright lies are considered to be blatant or total falsehoods.
• Exaggerations are considered to be overstated facts or “stretching the truth”, so to speak.
• Subtle lies (or lies of omission) involve leaving out the truth or omitting critical details (i.e., understating the facts).

This is not an exhaustive list. Lies tend to be varied, and people seem to be constantly coming up with new ways to deceive one another. Other colloquial phrases that capture different shades of lying include: fibs (or white lies), double-bluffs (a truthful statement told with deceptive intent), noble lie (a conspiracy that, if unraveled, could cause societal discord or disrupt civilized harmony).

So there are many kinds of lies. The next question is, what to people lie about most?

The most common contents of lies

• Feelings
• Achievements and knowledge
• Actions, plans, and whereabouts
• Explanations and motivations
• Facts and possessions

In addition to the major examples listed above, we all know from personal experience that people will also lie about relatively mundane things. For instance, low-stakes conversation topics like television shows, books, and hobbies are rife subject matter for lying because no one wants to seem like they’re out of the loop.

Next, the big question: How often do people lie?

Rates of deception

• DePaulo and colleagues (1998) reported that undergrads in their diary experiments admitted to telling 2 lies per day, while non-undergraduates admitted to telling 1 lie per day.
• Estimates range from 1 lie in every 3 social interactions for younger people, and 1 lie in every 5 for older people.
• These are estimates based on what people will admit to in an experimental setting. True numbers remain elusive because they depend on self-report. People also tend to vary on what they personally consider to be a lie.

These landmark social psychology studies uncovered a great deal about everyday human lying habits. In the two diary studies, undergraduates were instructed to record their lies during social interactions for a week. The second of the two studies also uncovered some interesting results about the nature of deception in different kinds of relationships.

Deception in relationships

• People tell fewer lies per social interaction to those they are close with (and felt more uncomfortable when they did so).
• More of the lies told to best friends and loved ones are prosocial in nature (Kashy & DePaulo, 1998).
• Lies told to close partners are more often discovered.

An underappreciated and somewhat controversial topic regarding deception relates to the circumstances under which lying occurs. You may be sitting there thinking, I’m an honest person—I only tell the good kinds of lies. But the truth is, given the right set of events, anyone can find themselves in a situation where lying might be automatic.

Context matters: deception on the internet

• People are far more likely to lie when they are no longer face-to-face.
• Deception rates increase when people interact over the internet, through email, or on social media (Hancock & Gonzales, 2013).
• Computer-mediated communication leads to increased deception rates (ibid).
• On the internet there is a diminished chance of giving away non-verbal cues to the other person as well as fewer opportunities for future interactions (i.e., there is less risk of the truth being revealed).

So now that we know all the basics about how and why people lie, let’s take a moment to examine what makes a good liar. Because if you’re going to lie, you might as well do it right. To be adept at lying, a person must have a certain set of cognitive skills in their arsenal.

The required cognitive skills

• Good attention span and executive control skills
• Good memory
• Good communication skills
• Lower capacity for guilt or empathy

You might have guessed based on these points that the kind of person who would be the best at lying is someone who is highly intelligent, doesn’t feel guilty about lying, or doesn’t even have insight into the fact that they’re lying. Unsurprisingly, the best liars tend to have the least compassion and empathy for others.

But not everyone who lies does so with ill-intent. Sometimes it’s pathological and a person simply can’t control it. In this vein, there are a variety of psychological conditions that either cause people to lie more frequently than normal or where the disorder itself involves an inability to detect reality from illusion.

Deception-related psychological conditions

• Confabulation: pathological lying without the knowledge or intent of doing so
• Asomatognosia: claiming that an arm or leg doesn’t belong to oneself
• Munchausen Syndrome and Munchausen by proxy: family of disorders that involves feighning disease, illness, or trauma in order to get attention or sympathy for oneself or a child
• Delusional Misidentification Syndromes: the belief that the physical or psychological identity of others or oneself has changed to something else. One notable example is Capgras Syndrome where a person claims another person or oneself has been replaced by an imposter.
• False Memories: a reality-monitoring error that involves a person having incorrect memories that tend to be self-serving in nature
• Sociopathy, psychopathy and anti-social personality: these are clinical disorders in which a component feature involves blatant deceit of others, often with little remorse

Conclusion

Deception can be a pretty ugly thing. As useful as it is, it can often cause more harm than it’s worth. With that said, we should end on a note of positivity and truth.

The only good liar is one that is aware of their own lies and makes continual efforts to confront this fact. Good liars come clean to others, especially when a lie could cause pain or suffering. Good liars notice when they’re ignoring the truth, and they strive to overcome the tendency to mislead. It would be naive to simply advise people to always tell the truth. Such advice is short-sighted and ignores a great deal of nuance about how humans prefer to interact with one another.

Just because it’s in our DNA to lie, doesn’t mean we can’t try to be better. Just think—if we communicate with compassion and take time to understand one another, then maybe honesty and sincerity will become the thing that future human societies become known for. Maybe that will become our most useful trick of all.

References

Chandler, M., Fritz, A., & Hala, S. (1989). Small-Scale Deceit: Deception as a Marker of Two-, Three-, and Four-Year-Olds’ Early Theories of Mind. Child Development, 60(6), 1263.

DePaulo, B. M., & Kashy, D. A. (1998). Everyday lies in close and casual relationships. Journal of Personality and Social Psychology, 74(1), 63.

Feldman, R. S., Forrest, J. A., & Happ, B. R. (2002). Self-presentation and verbal deception: Do self-presenters lie more?. Basic and Applied Social Psychology, 24(2), 163–170.

Ganis, G. (2003). Neural Correlates of Different Types of Deception: An fMRI Investigation. Cerebral Cortex, 13(8), 830–836.

Hancock, Jeff, and Amy Gonzales (2013). “Deception in Computer Mediated Communication.” In Pragmatics of Computer-Mediated Communication, edited by Susan C. Herring, Dieter Stein, and Tuija Virtanen, 363–83. Handbooks of pragmatics / eds. Wolfram Bublitz; Andreas H. Jucker; Klaus P. Schneider ; Volume 9. Berlin: de Gruyter Mouton. Accessed May 29, 2019.

Johnson, A. K., Barnacz, A., Constantino, P., Triano, J., Shackelford, T. K., & Keenan, J. P. (2004). Female deception detection as a function of commitment and self-awareness. Personality and Individual Differences, 37 (7), 1417–1424.

Kashy, D. A., & DePaulo, B. M. (1996). Who lies? Journal of Personality and Social Psychology, 70(5), 1037.

Stevens, M. (2016). Cheats and deceits. Oxford University Press.

Trivers, R. (2013). Deceit and self-deception. Penguin.

Vrij, A., & Granhag, P. A. (2012). Eliciting cues to deception and truth: What matters are the questions asked. Journal of Applied Research in Memory and Cognition,1(2), 110–117.

Whiten, A., & Byrne, R. (2002). Machiavellian intelligence II. Cambridge University Press.

Some of the content in this piece was previously presented in lecture format in a course developed by the author. Special Topics in Cognitive Science: The Science of Mind Reading was offered for two semesters at Stony Brook University.