6 Facts on the Thin Line Between Trust and Gullibility

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It’s April Fools’ Day, which means that an even smaller percentage than usual of the things you read on the internet today will turn out to be actually true. Skepticism wins the day. But most days, it’s often a smarter strategy to trust your fellow humans than not. In fact, highly trusting people are no more likely to be duped than skeptics, argued the late Julian B. Rotter, a University of Connecticut psychologist considered one of the foremost experts on interpersonal trust.

Here’s a brief wander through some of the most interesting findings Science of Us could dig up on trust, skepticism, and gullibility, specifically as they apply to our relationships with each other. You’ll want to read this, trust me.  

There’s a key difference between being trusting and being gullible. To trust and to be gullible both mean that you’ve decided you’re willing to make yourself a little vulnerable to another person. But to trust, as D. Harrison McKnight of Michigan State University defines it, according to his research, “typically means you have sought some basis for that willingness to depend,” he told Science of Us in an email. There’s a reason you’ve chosen to trust this person, in other words.

In contrast, gullible people “buy into a relationship swiftly with less evidence than most trusters,” McKnight continued. Depending on an untrustworthy person happens when you trust too quickly, without sufficient evidence, and without thinking things through. So the real distinction between being a trusting person and being a gullible person is that only one of those tendencies relies on evidence.

There are two factors we consider when deciding whether to trust. When you decide whether or not to place your trust in someone or something, you think about two things: integrity and competence, said David DeSteno, a psychologist at Northeastern University and the author of the 2014 book The Truth About Trust: How It Determines Success in Life, Love, Learning and More. “First, you have to ask yourself, Are they going to hold up their end of the bargain?” DeSteno said. That’s the integrity piece of the puzzle.

Once that has been verified, the second thing you need to know is whether this person is actually capable of performing this action he or she has promised. The way DeSteno usually describes it is that it’s the difference between a friend asking, Would you trust me to stick up for you if you were mugged? and Would you trust me to remove a cancerous tumor from your brain? You’d only trust a friend to do the latter if he’d previously proven himself to be (very!) competent.

There’s some evidence that trusting people are less likely to be gullible. That’s according to a 1980 paper authored by Rotter. In it, he reviewed the then-existing research, including a 1966 study that involved an ostensibly faulty electrical device that, at the start of the experiment, delivered a shock to the experimenter. The experimenter appeared to take a few moments to fix the device (when in fact he did no such thing and the subjects would soon be shocked themselves), and then assured the study participants that it was safe to proceed.

One group of study volunteers was given no reason not to trust the experimenter, but another group was told by one of the researchers, posing as a study subject, that he’d been tricked by the experimenter. Before beginning the experiment, the participants had taken tests meant to judge how trusting they tended to be, and in the first condition, the high-trusters were more likely to take the experimenter at his word than the low-trusters. No surprise so far.

But in the other condition, the high-trusters were no more likely to believe the experimenter than the low-trusters. “When gullibility is defined as naïveté or foolishness and trust is defined as believing in others in the absence of clear-cut reasons to disbelieve,” Rotter writes in that 1980 paper, “then it can be shown over a series of studies that high trusters are not more gullible than low trusters.”

Kids as young as 4 and 5 learn to avoid being duped. Research from Harvard’s Paul Harris has shown that from a very early age, we make strides in our ability to avoid being duped. Harris has run experiments in which 4- and 5-year-old kids are told they’re going to be taught some new material by two instructors: their usual teacher and a new person. It’s up to them which instructor they choose to go to. “You’d think the kids would go to the person they know and like,” said DeSteno, who wrote about Harris’s work in his book on trust. “But [Harris will] instruct the person they like to start making mistakes, and the kids are tracking that this person is making mistakes. So eventually, they’ll start seeking out the person who’s an expert, even if that person is a stranger.”

We judge a stranger as untrustworthy largely through nonverbal cues. DeSteno describes a study he led in which he asked the participants to play a game in which they’d have to decide to either act selfishly and cheat their competitor out of a cash reward, or play fair and risk the other player cheating them out of money. If both players acted fairly, both would walk away with an equal amount of money. DeSteno found that the more a player exhibited a series of certain nervous behaviors — crossing their arms, fidgeting, leaning away — the less likely the other player was to trust them.

But in interviews after the experiment, the players couldn’t exactly articulate why they’d decided not to trust their opponent. “Our minds are very good at using this information and forming a hunch,” DeSteno said. “So listen to your gut, because it’s telling you something very useful that you can’t extract on your own.”

When meeting someone new, people are more trusting toward each other than you might think. Back in 1993, when McKnight started studying trust in personal relationships, he expected to find that trust starts low between strangers and grows slowly over a long period of time. “I have found over and over that this is not at all true,” he said. “Average initial trust tends to start at somewhere around 5 on a 1-to-7 scale and then either grows or decreases, depending on experience with the other person.” With most people, trust isn’t something to be earned so much as it is something to have and then lose. 

6 Facts on Trust and Gullibility