Perhaps the easiest lie to detect is when someone says they have never lied. From social fibs, in which a person lies in order to protect someone else’s feelings or to benefit others, to self-enhancement fibs, in which a person lies to save face or avoid consequences. In a nutshell, lying plays a major role in our interactions in society.

So how did this innate ability to lie develop? Did it evolve from a survival instinct thousands of years ago, or is being dishonest more of a present-day manifestation to ensure personal gain?

While we may never discover the primal origins of the need to fabricate, we can understand how and why children develop the ability to lie. This knowledge can help us understand, to some extent, why we lie as adults.

Canada Research Chair in Developmental Psychology and Law Victoria Talwar examines children’s social-cognitive behaviour at McGill’s Talwar Research Team. According to Talwar, “the occurrence of lying in children is considered a normal cognitive development.”

Talwar explains that while lying is a positive sign of burgeoning intelligence and imagination in children, in adults, this childhood; discovery of fibbing can manifest itself in a manipulative manner because we are much more aware of either the personal gain or the avoidance of negative consequences that lying provides. Since lies themselves depend on context, place, and person, children do not really start to lie until pre-school age. Before reaching this stage, the reasons for lying are more to do with wish fulfilment then actual deception.

However, the motivations behind adult lies are less rooted on cognitive development. Based on a study conducted by Dan Ariely, professor of psychology and behavioural economicas at Duke University and described in his book The (Honest) Truth about Dishonesty, the science behind an adult’s decision to lie is far more profound and complicated then was thought.

Ariely conducted a series of experiments to examine the motives behind the desire to lie. He provided participants with math questions and directed them to solve as many as they could within a five-minute time frame. At the end of the five minutes, the group members received a monetary reward for each correct answer. The average number of questions answered was four in this particular group of people.

The experiment was altered with a different group of participants. Members were permitted to destroy their answers after they had completed the math problems, and were instead asked to simply state how many questions they had solved. As a result, members had the opportunity to lie, as there was no evidence to verify the truth in their responses. Within these altered conditions, the average number of questions correctly answered increased to seven.

Then, Ariely added a twist to the experiment. He increased the monetary value of each math problem solved correctly for this second group of participants. The findings were surprising. Participants in the second group did not adjust their fictitious results to show a larger number of correctly solved problems from their original lie. In other words, the participants in the second group were not inclined to be more deceitful when the opportunity to make more money per question was introduced to them.

Concordia graduate Nada Hafez, who completed her undergraduate studies with a bachelor of science in psychology, shed light on the interpretation of this experiment,

“These experiments demonstrate that [people are] constrained by a sense of their individual ethical guide [when lying],” Hafez said. “Why was the average number of questions solved within the group that lied not nine or even 10, but seven?”

She explained that this phenomenon is known as cognitive dissonance in psychology, where the participants experience discomfort as they struggle between two conflicting cognitions, the appeal of dishonesty and belief in telling the truth when reporting the number of math questions actually solved correctly.

“And in the process of this internal conflict what ends up happening is that, as in the case of the second group, they want to distort the truth enough to gain advantage from the situation but not so much that they feel they deviate from their moral schema,” Hafez concluded.

Evidently, our motivations for lying are a lot more complicated than we might think. It’s up to future studies in psychology to continue to shed light on why we engage in this behaviour.