Why Do We Lie? The Two Types of Dishonesty

This article is an excerpt from the Shortform book guide to "Predictably Irrational" by Dan Ariely. Shortform has the world's best summaries and analyses of books you should be reading.

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Why do honest people lie? What are the two types of dishonesty?

There are two types of dishonesty. The first type is the worst, it is the premeditated and sometimes criminal kind of lying. The second type is innocuous, the type that you’ve most likely done in everyday life like taking a pen from work. Find out why our brains are okay with little lies and where it sets the line.

Continue on for more about why we lie.

Why Honest People Act Dishonestly

Why do we lie? Well, there are two types of dishonesty. The first type is starkly criminal, premeditated, and at times violent—such as a bank robbery. The second type of dishonesty is non-violent and encompasses transgressions both criminal—such as embezzlement or insurance fraud—and relatively innocuous—such as swiping your coworker’s yogurt from the communal fridge.

Everyone is guilty of this second type of dishonesty—who hasn’t refilled their soda at a fast-food restaurant, or taken pens from work? What’s irrational is that though we recognize we’re guilty of dishonest actions, we irrefutably think of ourselves as good and honest people.

First, we’ll look at an experiment from MIT that aims to demonstrate how anyone—even those normally considered honest, upstanding people—can be easily tempted into dishonesty. Furthermore, this experiment explores how far people will go into their dishonesty when given the chance.

Experiment: How Much Do Honest People Cheat?

Participants were asked to take a test consisting of 50 multiple-choice questions, writing their responses directly on the test paper. After 15 minutes, they were to transfer their responses to an answer sheet. They would receive a reward of 10 cents for each correct answer. Each group tested under slightly different conditions.

Group A was the control group. They were told to give both their answer sheet and their test sheet to the exam supervisor, who would count their correct answers and give them the appropriate reward. On average, members of this group answered 32.6 questions correctly.
Group B received answer sheets that were lightly pre-marked with the correct answers—giving them the opportunity to change responses when transferring their answers from the test sheet. They were told to tally their correct answers on the answer sheet and write the number at the top. They would give both sheets to the supervisor, but he would only look at the number at the top of the answer sheet. On average, members of this group answered 36.2 questions correctly.
Group C also received pre-marked answer sheets. Students were instructed to destroy their test sheets and only give their answer sheets to the supervisor. On average, members of this group answered 35.9 questions correctly.
Group D also received pre-marked answer sheets. They were instructed to destroy both the test sheet and the answer sheet. Instead of letting the supervisor tally their answers and give them their reward, they were asked to simply take the correct amount of money from a jar at the front of the room. On average, members of this group took an amount of money equivalent to 36.1 correct answers.

The results suggest that when honest people have the opportunity to cheat, they will—but only a little. Each cheating group cheated about the same amount, regardless of risk. It seems that people have an inherent limit to acting with dishonesty.

Your Conscience (Usually) Sets the Limits

Usually, your decisions about whether or not to lie depend on your conscience, which is essentially the internalization of social values. When you act in line with society’s values, the reward center of your brain lights up and you don’t have the nagging voice in the back of your mind. But, when the way you act is not aligned with socially acceptable behavior, the conscience starts calling for you to change your behavior.

However, it seems that the conscience doesn’t have much influence when it comes to matters of dishonesty that are so small, you barely think about them. These moments may look like borrowing your sister’s shirt without asking or grabbing someone’s soda from the communal fridge. You don’t stop to consider if these actions have any bearing on your honesty, so your conscience isn’t triggered. The conscience kicks in when you consider transgressions that are large enough to make you wonder whether the action is wrong—such as selling a bag of your sister’s shirts at a thrift shop or taking an entire case of soda from the fridge.

Unfortunately, the influence of your conscience is only so strong—at times, the financial benefit of acting dishonestly can overpower your moral compass. This is frequently seen in fields like politics and medicine. A politician might call in some favors for a certain lobbyist, provided he’ll see a generous donation come campaign season. A doctor might prescribe medicine you don’t really need because he gets a kickback from the pharmaceutical company.

Of course, we try to put external controls in place to prevent this type of dishonesty from happening. But the promise of financial benefit is strong—and people easily find loopholes that allow them to continue their dishonest dealings. For example, lobbyists are banned from treating members of Congress to sit-down dinners—so they invite them to cocktail parties with passed hors d’oeuvres instead.

Why Do We Lie? The Two Types of Dishonesty