Whether it takes place around the water cooler or on Slack, gossiping about your co-workers seems like a bad idea. After all, it doesn’t do anyone any good to talk about them in secret, right? Science says we should think again: A new study on workplace psychology suggests that most of us are so oblivious to workplace competition that we won’t know when a rival is coming after us — which is why we need workplace gossip to give us the scoop.

The study, published the journal Psychological Science, suggests that we’re more trusting than we think we are. Titled “We Know Who Likes Us, but Not Who Competes Against Us,” the study outlines an experiment in which the researchers assessed how much employees in real-life offices actually understood how their co-workers felt about them. The result? As Hillary Anger Elfenbein, study co-author and professor of organizational behavior at Washington University in St. Louis., said in a statement, “You tend to know who likes you. But, for negative feelings, including competitiveness, people had no clue.” That’s why we have to rely on other people’s gossip for help.

She and her co-authors came to this conclusion by surveying a group of competitive employees at a Midwestern car dealership and, separately, 200 undergraduates who worked together in individual project groups, asking them what they thought of their colleagues — and what they thought their colleagues thought of them. Turns out that most people had a good sense of who liked them, but they had no clue who harbored negative, competitive feelings toward them.

What everyone in your office is thinking.

Why are we so clueless? Part of the reason is because we find it hard to see through workplace etiquette, which all individuals employ for their own benefit. As lead author and University of North Carolina professor of organizational behavior Noah Eisenkraft, Ph.D. explained to Inverse in an e-mail, “There are costs to signaling competitiveness, so people tend to keep these feelings under wraps.” We can’t count on these feelings to surface in public, so finding out what’s really going on depends largely on people disclosing these thoughts in private conversations — and their subsequent spread.

Another factor that makes it hard to detect feelings of competition, Eisenkraft explains, is the fact that underperformers want to compete with people they think are better than them — but the opposite doesn’t hold true. Competition, he says, often originates in social comparison: “Given the chance, anybody on earth would be motivated to run the 100-yard dash against Usain Bolt,” he says. “But Usain Bolt probably isn’t interested in competing against anybody except the best runners in the world.” The people who want to compete with you aren’t likely to be the people you want to compete with, making it easier to remain oblivious.

“When people are too polite to say something to your face, you need a good, strong network that will let you know what other people really think,” Elfenbein said in a statement. Gossip, it seems, does have a very important purpose: In fact, many evolutionary biologists have argued that private chit-chat between early humans is what strengthened social bonds and thereby kept society together. Then, as now, knowing how your peers really feel about you was useful for self-defense and survival — but thankfully, the consequences of workplace drama are usually not as grave as those of early human villages.