Why We Can't Ignore Lies, Even When We Know They're Lies

Research explains how we use irrelevant information in making decisions.

Posted Sep 27, 2020

Imagine this scenario: You are a loan officer at a bank reviewing a mortgage application of a recent college graduate with a stable, well-paying job and solid credit history. The applicant seems qualified, but during the routine credit check, you discover that the applicant has not paid a $5,000 debt on their credit card account. Do you reject or approve the application?

Now imagine this scenario: You are a loan officer at a bank reviewing a mortgage application of a recent college graduate with a stable, well-paying job and solid credit history. The applicant seems qualified, but during the routine credit check, you discover that the applicant has an unpaid debt on their credit card account. One report says that the debt is $5,000 and the other says $25,000. Do you reject or approve the application? Or, do you wait until you can resolve the discrepancy and get more information?

These are two scenarios used with business students to illustrate how irrelevant information influences decision-making.

Logically, people should respond to these same scenarios in the same way. In both situations, the applicant definitely has at least $5,000 in unpaid debt. However, in the first scenario, 60 percent of students reject the applicant and 40 percent approve. In the second scenario, only 4 percent reject, 8 percent approve, and 90 percent wait. Of those who wait, when they learn that the debt is $5,000, 80 percent approve the loan.

Think about this. In both scenarios, the applicant has at least $5,000 in unpaid debt, but when the possibility of a $25,000 debt is suggested—and found to be untrue—people are more lenient. Their evaluation of the $5,000 debt is altered by the completely false suggestion that there is a $25,000 debt.

This is just one example of how information that we know to be untrue can influence our decision-making. Why is that? Why do we let untrue, completely false information influence our judgments, opinions, and decisions?

The answer lies in our minds—our minds simply aren't able to ignore information once we have seen it. We can't unlearn things and we aren't able to label information, mentally, as irrelevant. As the saying goes, "You can't unring a bell." And, like a ripple on a pond, untrue information can create waves of disturbance that we may not be able to fix or forget. This is related to one of the most demonstrated effects in psychology: the anchoring effect. A great deal has been written about how the effect works—especially in terms of estimating numbers—and how to overcome it.

What is important to consider is that in a world where misleading and false information is constantly being presented in social media, we need to be aware of our vulnerability to that information—even when we know it is false, inflammatory, or intended to sway us. We like to think that we are not vulnerable—that Facebook posts, Twitter threads, and funny memes aren't affecting us—because of course, we know that they aren't 100 percent true or possibly even "just a joke."  

But science shows that we are vulnerable. When we see outlandish information, even when we know it is untrue, it sways our judgment. This is especially true if the information appeals to us on an emotional level. Our emotions do affect our decision-making and we are more likely to accept information that matches our desired emotional state. Fear makes us more attuned to risk information and anger makes us less aware of risk. 

So, is the answer to just turn off social media? Maybe. More information is not necessarily better. Research shows that Facebook algorithms are designed to present you with information that causes strong emotions, regardless of whether that information is true. And those strong emotions hijack your ability to think clearly and logically—especially if you are tired or not that motivated to think deeply about a topic.

To go back to the scenarios at the beginning of this post, people made better decisions when they didn't hear about the false $25,000 potential debt—so shielding yourself from emotional, false, and persuasive information can help you regain control of your decision-making and logic. If you find your social media full of emotionally-charged messages, don't "like" them, don't give it a heart or anger face—that just signals to Facebook that it needs to send you more emotionally-charged messages. Don't click on those posts and do unfollow pages that provide daily (and hourly) doses of anger and fear.

And, remember that we are all purveyors of information. So, when you see a post that makes you feel outraged, stop before reposting. Wait 24 hours (or two hours) and then decide if this is information that needs to be shared and why. Think about your goal in sharing the information. Once you put information out into the world—even if you and everyone you know realizes that it isn't entirely true or isn't the complete story—realize that these nuances can be lost. Information is not a salad buffet where people can pick out the good stuff and leave out the bad—information is a big stew of ideas and the influence of bad information on good cannot be separated.